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Up to date, about 600 species of freshwater (Decapods) crayfish from Astacida suborders was described in the world. Today, five species of freshwater crayfish from the family Astacidae (Astacus astacus, Astacus leptidactilus, Astacus pachypus, Austropotamobius pallipes and Austropotamobius torrentium) lives in Europe. Besides to autochthonous, now there are allochthonous species living there. They are mainly American species Pacifastacus leniusculus (Dana, 1852) also from the family Astacidae. All three species (A. astacus, A. pallipes and A. torrentium) are protected at European level: listed on IUCN Red List of threatened species (IUCN - International Union for Conservation of Nature) and they are also having been included in Appendix no. III of the Bern Convention by which their exploitation is under strict control and supervision of each state (Taylor, 2002), and type A. torrentium, and A. pallipes are in the Habitats Directive of the European Union. The goal of this dissertation was to analyze the populations of different species of freshwater (Decapods) crayfish from Montenegro in order to obtain information on their distribution, ecology, and to determine the phylogenetic and evolutionary relationships between individuals of species A. torrentium, A. pallipes and A. astacus sampled from Croatia, Serbia and Montenegro as well as their assessment of extinction risk and conservation priorities for biodiversity in aquatic ecosystems. The analysis included physically-chemical parameters of waters where was registered the presence of freshwater (Decapods) crayfish. For each caught crayfish 23 morphometric feature were measured and described by standard descriptive statistics (medium value, min-max value, standard deviation, and coefficient of variation). Same morphometric characteristics have been measured for the species A.astacus from the lake Buser-Serbia and they have also been described by the standard descriptive statistics. The data were then normalized on the way that their value was divided by the corresponding postorbital length (POL = HEL + ARL) and the results related to the morphometric characteristics were taken into account only the normalized input values. For normally distributed data we used the parametric T-test to compare differences of morphometric characters for males and females, and for a small number of samples we have been used Mann-Whitney U test. Variance analysis (ANOVA) was used to establish whether there are statistically important differences between populations of the same species or different species. Considering that there were differences, we worked discriminate analysis (DA). Phylogenetic analysis: Analysis by method of maximum parsimony (MP method) - was conducted by using program PAUP * 4.0b10 (Swoford, 2001). In order to obtain phylogenetic trees, files of gene sequences of 16S rRNA and COI in nexus format were analyzed. Each file was consisted of razing of multiple sequences of individual genes. Statistical analysis of probability of the proposed phylogenetic tree was…

Provedeno je kariološko-citogenetičko istraživanje na europskim autohtonim vrstama rakova Austropotamobius pallipes i A. torrentium iz porodice Astacidae. Vrsta A. pallipes ima diploidan broj kromosoma 2n=168, a vrsta A. torrentium ima 2n=164. Formula kariotipa za vrstu A. pallipes je 148m+18sm+2a, a za vrstu A. torrentium je 148m+16sm. Pomoću metode pruganja flurorescencijskom bojom 4,6-diamidino-2-fenilindol (DAPI) zabilježeno je da većina kromosoma vrste A. pallipes i A. torrentium sadrži heterokromatinske blokove smještene centromerno i pericentromerno. Na nekim kromosomima vrste A. torrentium nisu primijećene centromerne pruge, a na nekim kromosomima obje vrste su primijećene interkalarne heterokromatinske pruge. The aim of this study was karyological investigation of the European native crayfish species Austropotamobius pallipes and A. torrentium. The karyotype of A. pallipes consists of 2n=168 chromosomes, while the karyotipe of A. torrentium consists of 2n=164. The karyotype formulas are 148m+18sm+2a and 148m+16sm for A. pallipes and A. torrentium, respectively. Fluorochrome staining with 4,6-diamino-2-phenylindole (DAPI) has revealed that the majority of chromosomes of both A. pallipes and A. torrentium are characterised by large heterochromatic blocks located in the centromeric and pericentromeric positions. Some of A. torrentium chromosomes didn’t show centromeric bands, while some of the chromosomes of both species revealed presence of intercalary positioned heterochromatc bands.

Narrow-clawed crayfish (Astacus leptodactylus Eschscholtz, 1823 species-complex) is one of five European freshwater crayfish species. Even though widely distributed, it hasn’t been frequently studied and its taxonomy and systematics are unresolved. The results of a recent comparative morphometric character study revealed that morphometry of Asian and European populations differ significantly. In this research, for the first time, mitochondrial molecular markers (16S rRNA and COI) were used with the aim of elucidating the phylogenetic relationship between European and Asian populations of the narrow-clawed crayfish. Analyses included crayfish from Croatia, Bulgaria, Armenia, Russia, Poland and Turkey, and three different optimality criteria were applied. Phylogenetic relationships were reconstructed using the COI dataset, as well as the concatenated one (COI + 16S rRNA). For both datasets, congruent topologies were obtained and trees were characterised by the existence of two well supported phylogroups, one that included European populations, and the other Asian. Results indicate the presence of distinct evolutionary lineages within the A. leptodactylus species-complex, and corroborate previous results obtained using morphometric analyses.

Psorospermium spp. are unicellular organisms of uncertain taxonomic status found in the tissues of crayfish from three crayfish families. We describe the various life forms that we have identified in astacid, cambarid, and parastacid crayfish. A small amoeboid form, 10 μm, is described from juvenile North American Procambarus clarkii . A similar form had been described only once before in European Astacus astacus in the 1930s. Psorospermium spp. described to date are apparently otherwise immobile and often surrounded by a thick wall. Infection becomes apparent in 5th or 6th stage crayfish.

La proportion d'espèces allochtones dans les peuplements français de crustacés décapodes d'eau douce est importante. Pour deux espèces de crevettes (famille des Atyidae) et trois espèces d'écrevisses (famille des Astacidae) autochtones, on compte quatre espèces d'écrevisses (famille des Astacidae et Cambaridae) et deux espèces de crabes importées (famille des Grapsidae et Potamonidae). S'appuyant sur des données d'inventaires nationaux, cette présentation dresse un rapide bilan du contexte écologique, réglementaire et humain.

Cambarus robustus (Astacidae, Crustacea) females from acidic, metal-contaminated Wavy Lake and circumneutral, uncontaminated, fast-flowing Pike Creek showed significant allometric differences (relationships between total body length and wet mass, total body length and chela length, and carapace length and carapace width), as well as differences in their fecundity (relationships between total body length and numbers of eggs per ovary and numbers of eggs per ovary and diameter of eggs). Whereas crayfish from Pike Creek showed linear relationships between total body length, wet mass, and chela length (= isometry), decapods from Wavy Lake showed isometry only between total body length and chela length. Females from Pike Creek produced significantly more but smaller ovarian eggs than did those from Wavy Lake. Oxygen consumption was significantly lower and ammonia excretion significantly higher in crayfish from Wavy Lake than in those from Pike Creek.

The American Fisheries Society (AFS) Endangered Species Committee herein provides a list of all crayfishes (families Astacidae and Cambaridae) in the United States and Canada that includes state and provincial distributions; a comprehensive review of the conservation status of all taxa; and references on biology, conservation, and distribution of crayfishes. The list contains 338 native crayfishes, of which 2 (< 1%) taxa are listed as endangered, possibly extinct; 65 (19.2%) as endangered; 45 (13.3%) as threatened; 50 (14.8%) as special concern; and 176 (52.0%) as currently stable. Limited natural range is implicated as the primary factor responsible for the noted imperilment of crayfishes; other threats include habitat alteration and the introduction of nonindigenous crayfishes. Using the best available information, we estimate that almost 50% of crayfishes in United States and Canada are in need of conservation recognition. We hope that this report spurs increased research efforts from aquatic ...

Täplärapu (Pacifastacus leniusculus) on Suomen vesistöissä verrattain uusi vieraslaji, joka leviää sekä suunnitelluin istutuksin että suunnittelematta uusille alueille. Täplärapu on alun perin tuotu Suomeen korvaamaan rapuruton turmelemia jokirapukantoja, mutta sitä on istutettu myös alueille, joissa ei alkuperäistä rapukantaa ole aiemmin ollut. Kotoperäiseen jokirapuun verrattuna täplärapu on paitsi vastustuskykyisempi rapurutolle, myös nopeampi kasvamaan ja lisääntymään. Täplärapu kasvaa jokirapua suuremmaksi ja on luonteeltaan aggressiivisempi. Vieraslajina täplärapu voi muuttaa uuden elinympäristön rakennetta ja toimintaa. Täplärapu käyttää ravintonaan muun muassa selkärangattomia pohjaeläimiä, jotka toimivat myös kalojen loisten väli-isäntinä. Vaikuttaessaan pohjaeläinyhteisöihin täpläravut voivat siten vaikuttaa myös loisten runsauteen ja yleisyyteen alueella. Tässä tutkimuksessa pyrittiin selvittämään, miten täpläravun läsnäolo alueella voi vaikuttaa saman alueen särkien (Rutilus rutilus) loisyhteisöihin. Tutkimuksessa määritettiin Päijänteellä olevilta havaintoalueilta (n = 10) verkoin pyydystetyistä särjistä (n = 188) niiden loiset ja verrattiin loisyhteisöjä ravuttomien (n = 5) ja ravullisten alueiden (n = 5) välillä, perustuen havaintoalueiden keskiarvoihin. Vertailut tehtiin sekä loislajeittain että väli-isäntäkohtaisesti. Tutkimuksessa havaittiin vesisiiraa (Asellus aquaticus) väli-isäntänään käyttävän Acanthocephalus lucii –väkäkärsämatoja merkitsevästi vähemmän ravullisten alueiden särjillä. Toinen tilastollisesti merkitsevä ero havaittiin simpukkavälitteisten Rhipidocotyle fennica –imumatojen esiintyvyydessä. R. fennica oli yleisempi ravullisilla alueilla. Kun loiset jaettiin ryhmiin väli-isäntiensä perusteella, ei simpukkavälitteisillä, kotilovälitteisillä tai hankajalkaisten loisilla havaittu eroja ravullisten ja ravuttomien alueiden välillä. Tämä tutkimuksen tulokset vahvistavat osittain aiempia tutkimustuloksia täpläravun mahdollisista seurannaisvaikutuksista kalojen loisyhteisöihin, mutta toisaalta osoittavat, että vaikutusten esiintyminen ja voimakkuus riippuvat myös kalaisäntien ekologiasta ja habitaatin käytöstä. Signal crayfish (Pacifastacus leniusculus) is an alien species spreading planned and unplanned in Finnish freshwaters. Signal crayfish has been introduced to compensate for the reduction of endemic noble crayfish stocks (Astacus astacus) due to crayfish plague. Signal crayfish has been introduced also into areas with no previous crayfish population. Compared to the endemic species, signal crayfish is more resistant to the plague and has faster growth and reproduction rate. Adult signal crayfish is larger in size than the endemic species and more aggressive in its behavior. As an alien species, it can change the structure and function of the ecosystem. Crayfish feeds partly on freshwater invertebrates. These same invertebrates can act as hosts for fish parasites. By eating invertebrates, signal crayfish might affect the abundance and prevalence of fish parasites. In this study, the aim was to investigate if the signal crayfish can affect the parasites of roach (Rutilus rutilus) in a large lake ecosystem, previously naive to crayfish. The study was conducted at lake Päijänne, the parasites were determined from roaches (n = 188) caught in the study sites (n = 10) by gillnets. The average abundances and prevalences of parasite species found from roach in each study area were compared between areas with (n = 5) and without (n = 5) signal crayfish. Comparisons were made also by grouping the species according to their invertebrate hosts. The study revealed less Acanthocephalus lucii –infections on roaches caught from study sites with signal crayfish. The intermediate host of A. lucii is waterlouse (Asellus aquaticus). Rhipidocotyle fennica, a trematode parasitizing bivalves, was more prevalent on roaches caught in areas with crayfish. There were no significant differences when comparing parasites as groups infecting bivalves, gastropods or copepods. This study brings out new information about the effects of signal crayfish, an introduced alien species, on fish parasite communities. On the other hand, it has been demonstrated that the occurrence and strength of effects depend also on the ecology and habitat of fish hosts.

Research of the population of crayfish of the family Astacidae on the territory of Montenegro and Serbia by using COI gene mDNA as a genetic marker, have shown that all populations of the species Austropotamobius torrentium are homogenous and belonging to the haplogroup “Southern Balkan”. Population of Austropotamobius italicus, recorded only in Montenegro in river Zeta’s upper flow, belongs to the (haplogroup), subspecies meridionalis. The findings of Austropotamobius italicus meridionalis are new and an expansion of the southern range border of this subspecies in the Balkan peninsula. For the populations of Astacus astacus, two haplogroups have been detected ; the one from Serbia belongs to a new haplotype and is considered to be evolutionally older than the ones from Montenegro and Croatia. Using COI gene analysis, the highest value of nucleotide diversity (π) was noted for the species Austropotamobius torrentium, π = 4.6% (0.046±0.006) ; the lowest one was for the species Astacus astacus, π = 3.2% (0.032±0.006). The achieved results implicate urgent measures for conservation of populations Astacus astacus on the territory of Serbia and Austropotamobius italicus meridionalis on the territory of Montenegro, accompanied by the use of stricter measures in the management of populations of Astacus astacus in Montenegro.

Ovaj rad donosi nove informacije o kariološkim značajkama autohtonih europskih vrsta slatkovodnih rakova iz rodova Astacus i Austropotamobius (Decapoda, Astacidae). Vrsta Astacus astacus ima diploidan broj kromosoma 2n=176, vrsta A. leptodactylus ima 2n=180, a vrsta Austropotamobius torrentium ima 2n=164. Formula kariotipa za vrstu A. astacus je n=88, 52m+35sm+1a, a za vrstu A. torrentium formula kariotipa je n=87, 78m+8sm+1t. Fluorescencijsko pruganje bojom 4,6-diamidino-2-fenilindol (DAPI) pokazalo je da vrste roda Astacus posjeduju velike heterokromatinske blokove smještene centromerno na svim kromosomima, dok vrsta A. torrentium samo na nekim kromosomima. Interkalarni heterokromatinski blokovi nađeni su na nekim kromosomima u sve tri vrste. U vrstama A. astacus i A. leptodactylus sparivanje kromosoma u mejozi je pravilno, a većina bivalenata su kružnog i zvonolikog oblika. Fluorescencijska hibridizacija in situ (FISH) otkrila je da vrste A. astacus i A. leptodactylus imaju po dva lokusa za 45S rRNA. U vrsti A. leptodactylus uočen je dodatni 45S rDNA signal. This study gives karyological information on native European species Astacus astacus, A. leptodactylus and Austropotamobius torrentium (Decapoda, Astacidae). Astacus astacus has a diploid chromosome number 2n=176, species A. leptodactylus has 2n=180 and species Austropotamobius torrentium has 2n=174 chromosomes. Karyotype formula of A. astacus is n=88, 52m+35sm+1a, while for A. torrentium the formula is n=87, 78m+8sm+1t. Fluorescence banding with 4,6-diamidino-2-phenylindol (DAPI) has shown long heterochromatic blocks in centromeric regions of all chromosomes in Astacus species, and on some chromosomes in species A. torrentium. Interstitial blocks are found in some chromosomes of all three species. Meiotic pairing of chromosomes is regular in A. astacus i A. leptodactylus, and most of bivalents are in ring and dumbbell form. Furthermore, fluorescence in situ hybridization (FISH) reveals two 45S rDNA loci in both A. astacus and A. leptodactylus. An additional 45S rDNA signal was found in A. leptodactylus.

Native freshwater faunas in North America are declining, principally due to the combined effects of habitat degradation and introduced species. Relatively little attention has been directed to the decline of freshwater invertebrates, which may be even more threatened than fishes. This paper chronicles recent changes in the distribution and abundance of the Shasta crayfish (Pacifastacus fortis Faxon), a state and federally endangered species endemic to the midreaches of the Pit River system in northeastern California. We made snorkeling and SCUBA surveys for crayfish in 1990 and 1991 and examined various records for historic distributions. Shasta crayfish have been extirpated from much of their historic range by water impoundment and diversion, and they are further threatened by two introduced crayfish species (Pacifastacus leniusculus Dana and Orconectes virilis Hagen). By 1990 Shasta crayfish were restricted to seven isolated populations, mostly in the headwaters of spring-fed tributaries to the Pit river. P. leniusculus had become established throughout much of the study area in about 12 years. In one site P. leniusculus probably contributed to the precipitous decline of Shasta crayfish, from 2000–3000 in 1980 to about 370 (± 135) in 1991. O. virilis, which occurred in only the most disturbed parts of the system, showed little range expansion in 30 years and had been replaced in a large stretch of the Pit River by P. leniusculus. P. leniusculus occupied sites with a broad range of habitat variables (temperature, pH, turbidity, substrate size) partly or wholly overlapping measures of sites with the other two species. The decline of the Shasta crayfish, like the extinction of its closest relative P. nigrescens in the San Francisco Bay area earlier this century, reflects the decline of its habitat and probably pressure from the aggressive exotic P. leniusculus.

In this short note we report the sudden and numerically significant expansion of signal crayfish (P. leniusculus) from Piedmont towards Liguria. P. leniusculus (Decapode Astacidae) is native to northwestern America, introduced in Italy in 1981 in the province of Bolzano, a few years later it was reported in Brugneto Lake (Genova district) and during the 2009 in the Valla stream (Alessandria district). The peculiarities of this species, originally from “cold water”, making it potentially invasive in the Apennine watercourses and also the presence of this allochthonous decapod in the Savona district, would like to suggest the implementation of containment plans, acts at least to limit its spread.

This study reports about the spermatozoal ultrastructure of three species of astacid crayfish, i.e., the stone crayfish Austropotamobius torrentium, signal crayfish Pacifastacus leniusculus, and noble crayfish Astacus astacus. The acrosome is a cup shaped and electron-dense structure at the anterior of the spermatozoon and comprises three layers of differing electron densities filled with parallel filaments that extend from the base to the apical zone. The acrosome was significantly longer in A. astacus than in P. leniusculus and the shortest acrosome belongs to A. torrentium. The width of the acrosome was significantly narrower in A. torrentium than in P. leniusculus and the widest acrosome belongs to A. astacus. The L:W ratio was significantly greater in A. torrentium than in P. leniusculus and the lowest ratio belongs to A. astacus. Radial arms are visible on each side of the acrosome or nucleus in sagittal view and wrap around the spermatozoon. Each radial arm comprises a parallel bundle of microtubules arranged along the long axis within a sheath. The nucleus, with decondensed material, is located in the posterior of the cell. All parts of the spermatozoon are tightly enclosed within an extracellular capsule. Despite a well-conserved general structure and similarity of pattern among these spermatozoa, differences in the dimensions of the acrosome within the studied species may be useful to help distinguish the different crayfish species. J. Morphol., 2013. © 2013 Wiley Periodicals, Inc.

Pacifastacus nigrescens (Stimpson, 1857) (Fig. 30B, K) Astacus nigrescens Stimpson, 1857a: 87; 1857b: 492. — Hagen 1870: 92, pl. III, fig. 168. — Holmes 1900: 166. — Bonnot 1930: 212. Pacifastacus nigrescens. — Riegel 1959: 44 (part, figures probably are of P. fortis). — Hobbs 1976: 23, fig. 13b, 14d. — Kuris et al. 2007: 636.— Larson & Olden 2011: 62. Diagnosis. Similar to P. leniusculus except rostrum concave, with prominent, acute apex; 5 or 6 lateral teeth, small spinules on postorbital ridges. Major chelae without clusters of setae, chela narrow, palm barely wider than closed fingers, fingers may be gaping. Abdominal pleura sharply triangular. Total length 78 mm. Color in life. Blackish. Habitat and depth. Streams near the coast. Depth not reported. Range. Unalaska, Alaska; Fort Steilacoom, Washington, Alameda Creek, Alameda County and Coyote Creek, Santa Clara County, California (Holmes 1900). Type locality given as San Francisco, California, but Stimpson said that he purchased his specimens in a market. Remarks. There have been no reliable records of live P. nigrescens since those of Holmes (1900). Subsequent reports by Bonnot (1930) quoted Holmes or considered P. fortis to be a subspecies of P. nigrescens (Riegel 1959). Holmes' specimens probably were burned in the fire following the San Francisco earthquake in 1906, so it is impossible to double-check the identification of his material from Washington and Alaska., Published as part of Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, pp. 1-307 in Zootaxa 3371 on page 127, {"references":["Stimpson, W. (1857 a) Notices of new species of Crustacea in western North America being an abstract from a paper to be published in the Journal of the Society. Proceedings of the Boston Society of Natural History, 6, 84 - 89.","Stimpson, W. (1857 b) On the Crustacea and Echinodermata of the Pacific shores of North America. Journal of the Boston Society of Natural History, 6, 444 - 532.","Hagen, H. A. (1870) Monograph of the North American Astacidae. Illustrated Catalogue of the Museum of Comparative Zoology at Harvard College, 3, 1 - 109.","Holmes, S. J. (1900) Synopsis of California stalk-eyed Crustacea. Occasional Papers of the California Academy of Sciences, 7, 12 - 62.","Bonnot, P. (1930) Crayfish. California Fish and Game, 16, 212 - 216.","Riegel, J. (1959) The systematics and distribution of crayfishes in California. California Fish and Game, 45, 29 - 50.","Hobbs, H. H. Jr. (1976) Crayfishes (Astacidae) of North and Middle America. United States Environmental Protection Agency, Water Pollution Control Research Series 18050 ELDO / 72, Cincinnati, Ohio, 173 pp.","Kuris, A. M., Sadeghian, P. & Carlton, J. T. (2007) Keys to Decapod Crustacea. In: Carlton, J. T. (Ed.) The Light and Smith Manual: Intertidal Invertebrates Central California to Oregon. University of California Press, Berkeley, 4 th ed., pp. 636 - 656.","Larson, E. R. & Olden, J. D. (2011) The state of crayfish in the Pacific Northwest. Fisheries, 36, 60 - 73."]}

Pacifastacus fortis (Faxon, 1914) (Fig. 30C, J) Astacus nigrescens fortis Faxon, 1914: 360, pl. 7, fig. 5; pl. 9, fig. 2. Pacifastacus nigrescens. — Riegel 1959: 44, fig. 3D, 9 (in part). Pacifastacus fortis. — Hobbs 1976: 23, fig. 13c, 14c. — Eng & Daniels 1982: 197, fig. 1a. — Larson & Olsen 2011: 62. Diagnosis. Similar to P. leniusculus except rostrum with numerous sharp teeth. Postorbital ridges with sharp teeth. Major chela with out patches of setae, width of chela equal to or greater than length of mesial margin. Male abdomen narrower, major chelae heavier than those of female. Carapace length to 50 mm. Color in life. Dark brownish green to dark brown dorsally, bright orange ventrally, occasionally blue-green to bright blue with light salmon color below (Eng & Daniels 1982). Habitat and depth. Cool, clear, spring-fed lakes, streams; under rocks on clean firm sand or gravel, shallow. Range. Streams in Fall River, Hat Creek sub-drainages, area of Pit River connecting them, in Shasta County, California. Type localities Fall River Mills and Hat Creek near Cassel, California. Remarks. Riegel (1959) considered P. fortis to be a subspecies of P. nigrescens, and included records of P. fortis in his account of the range of P. nigrescens. His records from Fall River, Fall "City" [sic] Mills, (the correct name is Fall River Mills), and Hat Creek at Cassel surely belong to P. fortis. Eng & Daniels (1982) prepared an extensive report on the threatened Shasta crayfish., Published as part of Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, pp. 1-307 in Zootaxa 3371 on page 124, {"references":["Faxon, W. (1914) Notes on the crayfishes in the United States National Museum and the Museum of Comparative Zoology, with descriptions of new species and subspecies to which is appended a catalogue of the known species and subspecies. Memoirs of the Museum of Comparative Zoology at Harvard College, 40, 351 - 427.","Riegel, J. (1959) The systematics and distribution of crayfishes in California. California Fish and Game, 45, 29 - 50.","Hobbs, H. H. Jr. (1976) Crayfishes (Astacidae) of North and Middle America. United States Environmental Protection Agency, Water Pollution Control Research Series 18050 ELDO / 72, Cincinnati, Ohio, 173 pp.","Eng, L & Daniels, R. (1982) Life history, distribution, and status of Pacifastacus fortis (Decapoda: Astacidae). California Fish and Game, 68, 197 - 212."]}

Pacifastacus connectens (Faxon, 1914) (Fig. 30G, H) Astacus connectens Faxon, 1914: 360, pl. 7, figs 6, 10; pl. 10, fig. 1. Pacifastacus connectens. — Hobbs 1976: 22, figs. 12d, 14a. — Larson & Olden 2011: 62, p. 61 fig. A. Diagnosis. Similar to P. leniusculus except rostrum with numerous lateral teeth, tubercles. Postorbital ridges with 1–2 pairs posterior teeth or tubercles, rostrum lacking median carina. Dorsal surface of major chela with two conspicuous patches of setae, as well as prominent tubercles in patches. Palm of chela not much wider than fingers, edges more or less straight. Male total length 65 mm, carapace length 34 mm. Color in life. Brown. Habitat and depth. Rivers, streams; shallow. Range. Idaho and Oregon, see map by Larson & Olden (2011: Fig. 1). Type locality Snake River, Idaho., Published as part of Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, pp. 1-307 in Zootaxa 3371 on page 124, {"references":["Faxon, W. (1914) Notes on the crayfishes in the United States National Museum and the Museum of Comparative Zoology, with descriptions of new species and subspecies to which is appended a catalogue of the known species and subspecies. Memoirs of the Museum of Comparative Zoology at Harvard College, 40, 351 - 427.","Hobbs, H. H. Jr. (1976) Crayfishes (Astacidae) of North and Middle America. United States Environmental Protection Agency, Water Pollution Control Research Series 18050 ELDO / 72, Cincinnati, Ohio, 173 pp.","Larson, E. R. & Olden, J. D. (2011) The state of crayfish in the Pacific Northwest. Fisheries, 36, 60 - 73."]}

Pacifastacus leniusculus (Dana, 1852) (Fig. 30D–F, L) Astacus leniusculus Dana, 1852: 524. — Stimpson 1857b: 493. — Hagen 1870: 94. — Holmes 1900: 166. — Bonnot 1930: 212, figs. 65–67. Pacifastacus leniusculus. — Riegel 1959: 39, fig. 1F–H, fig. 3A, 6. — Miller & Van Hyning 1970:77, figs. 1, 2. — Abrahamsson & Goldman 1970: 83. — Hobbs 1976: 21, figs. 5a,12 a–c, 14e. — Eng & Daniels 1982: 200, fig. 1a. — McGriff 1983: 227. — Kuris et al. 2007: 636. — Larson & Olden 2011: 64, p. 61 figs. C, D. Diagnosis. Rostrum acute, with single pair marginal teeth or tubercles, with or without median carina, with dorsal surface depressed. Postorbital ridges rounded or with pair of teeth or tubercles. Carapace with prominent cardiac grooves, paired branchiocardiac grooves, branchial regions slightly to greatly inflated. First antennae small, peduncle about same length as rostrum. Basicerite of second antenna with sharp lateral tooth. Scaphocerite with acute lateral tooth, as long as or slightly longer than rostrum. Third maxilliped setose, ischium armed with sharp spines on mesial, lateral margins of distal margin (forming "crista dentata"), next segment armed with spinules. Major chelae with smooth to tuberculate surface. Length of fingers about 3 times as long as length of palm, fixed finger with low tooth on cutting edge near proximal end. Outer margin of palm convex, inner convex, flared proximal to dactyl. Inner margin of palm with crest, slight depression parallel to crest on inner, upper, lower surface of palm. Carpus with blunt tooth at distal margin, sharp notch along articulation with chela, 2 teeth on lower margin along distal edge. Merus with large tooth at distal inner end, large tooth, row of teeth along lower edge, 2 teeth parallel, inner to this row. Ischium with tubercles in line with those of merus. Pereopods 2, 3 chelate, sparsely setose. Pereopods 4, 5 with dactyls forming claws. Ischia of all pereopods lacking hooks. Male pleopod 1 simple in structure, slender setose ridge along distal mesial surface. Male pleopod 2 with strong endopod, slender exopod. Female pleopod 1biramous. Abdomen heavy. Abdominal somites decreasing in size from 1–5, with pleura ending in points curving posteriorly. Pleura of abdominal somite 6 prolonged into hook around base of uropods. Telson with horizontal fissure along dorsal surface near posterior end, 2 lateral teeth in line with this fissure. Outer uropod with fissure across dorsal surface, 2 lateral teeth along fissure, median ridge. Inner uropod with median ridge. Total length to 117 mm. Color in life. Dark brown to dark greenish. The color notes are from specimesn from Lake Tahoe, Nevada. Habitat and depth. Rivers, streams, lakes, sloughs; less than 1 m to as much as 40 m (Lake Tahoe, Abrahamsson & Goldman 1970). Range. British Columbia, Washington, Idaho, Oregon, Nevada (Lake Tahoe area) and California, south at least as far as Little Sur River, Monterey County. Introduced into Sweden. Type locality Columbia River, Oregon. Miller & Van Hyning (1970: fig. 3) provided a map of the range of the species in Oregon. Larson & Olden (2011: fig. 1) gave a map of the distribution of the subspecies in Oregon, Washington, southern British Columbia and extreme northwestern California. Remarks. Three subspecies of P. leniusculus have been described: P. leniusculus leniusculus (Dana, 1852); P. leniusculus klamathensis (Stimpson, 1857) and P. leniusculus trowbridgii (Stimpson, 1857). Hobbs (1976) noted that the descriptions do not clearly define these subspecies, and their ranges overlap. Due to human activity, the subspecies have been introduced into new areas and have intermingled., Published as part of Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, pp. 1-307 in Zootaxa 3371 on page 126, {"references":["Stimpson, W. (1857 b) On the Crustacea and Echinodermata of the Pacific shores of North America. Journal of the Boston Society of Natural History, 6, 444 - 532.","Hagen, H. A. (1870) Monograph of the North American Astacidae. Illustrated Catalogue of the Museum of Comparative Zoology at Harvard College, 3, 1 - 109.","Holmes, S. J. (1900) Synopsis of California stalk-eyed Crustacea. Occasional Papers of the California Academy of Sciences, 7, 12 - 62.","Bonnot, P. (1930) Crayfish. California Fish and Game, 16, 212 - 216.","Riegel, J. (1959) The systematics and distribution of crayfishes in California. California Fish and Game, 45, 29 - 50.","Miller, G. & Van Hyning, J. (1970) The commercial fishery for fresh-water crawfish, Pacifastacus leniusculus (Astacidae) in Oregon, 1893 - 1956. Research Reports of the Fish Commission of Oregon, 2, 1 - 13.","Abrahamsson, S. & Goldman, C. 1970. Distribution, density and production of the crayfish Pacifastacus leniusculus Dana in Lake Tahoe, California-Nevada. Oikos - 31, 1 - 91.","Hobbs, H. H. Jr. (1976) Crayfishes (Astacidae) of North and Middle America. United States Environmental Protection Agency, Water Pollution Control Research Series 18050 ELDO / 72, Cincinnati, Ohio, 173 pp.","Eng, L & Daniels, R. (1982) Life history, distribution, and status of Pacifastacus fortis (Decapoda: Astacidae). California Fish and Game, 68, 197 - 212.","McGriff, D. (1983) Growth, maturity, and fecundity of the crayfish, Pacifastacus leniusculus, from the Sacramento-San Joaquin Delta. California Fish and Game, 69, 227 - 242.","Kuris, A. M., Sadeghian, P. & Carlton, J. T. (2007) Keys to Decapod Crustacea. In: Carlton, J. T. (Ed.) The Light and Smith Manual: Intertidal Invertebrates Central California to Oregon. University of California Press, Berkeley, 4 th ed., pp. 636 - 656.","Larson, E. R. & Olden, J. D. (2011) The state of crayfish in the Pacific Northwest. Fisheries, 36, 60 - 73."]}

Within the scope of a research project on decapod crustaceans in Montenegrin aquatic ecosystems, a population of white-clawed crayfish of the Austropotamobius pallipes/italicus species complex has been recorded for the first time. Based on an analysis of morphometric and genetic parameters, it has been established that Austropotamobius italicus (Faxon, 1914) and its subspecies meridionalis are distributed in Dalmatia and in the central and southern parts of the Apennine Peninsula. The new finding represents: (1) extension of the known range of the species complex A. pallipes/italicus on the Balkan Peninsula, and (2) determining the limits of the distribution and of this isolated population of that complex. The ascertained characteristics of the white-clawed crayfish's newly discovered population in Montenegro are significant from the viewpoint of global conservation of the species in question. Ministry of Education and Science of the Republic of Serbia [43002, 173025]

This paper presents data on geographical distribution and ecological preferences of Austropotamobius torrentium species following investigations of 104 sampling sites in the west and north-western Romania. Specimens were caught by actively searching the river bed, after which they were released. A detailed map of the distribution was prepared: the species was found to be living in 23 sampling sites from three basins: Crisul Alb, Crisul Negru and Crisul Repede. The current distribution of the species extends to the central and eastern part of the Codru Moma Mountains, western Bihor Mountains, eastern Padurea Craiului Mountains, central and northern areas of the Vladeasa Mountains and southern and central areas of the Plopis Mountains. The northernmost population of Romania is found in the Valea Mare River, on the Plopis Mountains. Generally, the species occurs on a substrate consisting primarily of stone and gravel. The species’ preferred combination of riparian vegetation is Alnus sp. and Salix sp. in deciduous forests. An important number of investigated rivers, totalling 37, are occupied by the Astacus astacus species, data proving that there are no mixed populations. No other non-indigenous crayfish species were found during this study.

Summary The comparative morphology of the foregut during development from embryonic larva to adult in Cherux quadricarinatus was examined by light and scanning electron microscopy. Major ontogenetic changes occurred in the gastric mill dentition in terms of denticle shape, appearance of vertical ridges in the lateral teeth, roughness of masticating surfaces, degree of sclerotization and proportional sizes of the median tooth components. Natural food types appropriate for the various life history stages during artificial rearing of C. quadricarinatus may be inferred from the morphology of the gastric mill dentition of those stages. Cardiopyloric valves and the gland filter appeared prior to development of functional gastric mill teeth. Compared with the foregut of adult astacid crayfish, that of adult C. quadricarinatus shows differences in the ventral cardiopyloric valve, pyloric funnel and lateral valves.

Austropotamobius torrentium (Schrank, 1803), the smallest species of freshwater crayfish from the family Astacidae, is considered a vulnerable species, protected by international laws. Since it has never been economically important, it has not been frequently studied. Therefore, the results presented in this paper are a contribution to the knowledge on stone crayfish’s population size structure, size at maturity, growth, and condition index throughout the year, as a possible tool for evaluating protection and restocking measures of this threatened species. The research included three stone crayfish populations with 1492 specimens in the “Medvednica” Nature Park, north-west Croatia, during a period of 18 months. In all the populations studied, crayfish of a total length between 5 and 8 cm prevailed. Activity of different size classes had a seasonal pattern that could be connected to different crayfish activities throughout the year. Appearance of sexual maturity within the populations coincides with the crayfish total length between 5 and 6 cm, after which allometric growth of males’ claws was recorded. On average males gain 0.42−0.72 cm and 2.65−4.30 g per moult, while females gain 0.44−0.70 cm and 2.04−3.83 g. Crayfish condition varied throughout the year with, in general, both juvenile and adult males having higher condition indices than juvenile and adult females in all three populations. In addition, adult crayfish were in significantly better condition in the autumn, whereas juveniles had higher condition indices in the summer.

The additional supply of live feeds such as Artemia remains indispensable in juvenile astacid rearing from the start of independent life. Considering that cost and work could be reduced by restricting this supply, a 100-day experiment was carried out with stage 2 Pacifastacus leniusculus to evaluate the effects of different administration periods of decapsulted Artemia cysts as supplement to a dry diet at two stocking densities. Using a bifactorial design, six treatments differing in the time at which the cysts were withdrawn (after 20, 30 or 50 days of experiment) and the stocking density (100 or 200 crayfish·m-2 ) were conducted. Survival rates did not show significant differences among groups, with final figures averaging 81%. Crayfish receiving cysts up to day 50 showed faster growth (around 13.8 mm carapace length and 610 mg weight at the end of the experiment) than the rest, significant differences being recorded from day 60 of experiment onwards. The 20-day and 30-day supplies resulted in similar growth values. There were no significant differences in survival or growth between 100 and 200 crayfish·m-2 . This study shows that decapsulated Artemia cysts can be withdrawn at day 20 (allowing to feed a dry diet as the sole food thereafter) and that faster growth can be obtained if cysts are supplied up to day 50. Furthermore, a stocking density of 200 crayfish·m-2 can be advised under the mentioned feeding conditions.

We report two rare examples of preservation by calcareous incrustation of two specimens of decapod crustaceans, discovered in continental carbonate deposits from the Pleistocene (Late Cenozoic) of SW Turkey (W Anatolia) and S Kazakistan (“Caucasian Area”) respectively. The specimen from Turkey is assigned to Potamon Savigny, 1816 (Potamidae) while the specimen from Kazakistan is assigned to Austropotamobius Skorikov, 1907 (Astacidae).

Cadmium and copper contents of the hepatopancreas in adult intermoult Cambarus bartoni , exposed for 72 h to 12.5, 62.5 and 125 μg Cd 1 −1 , were significantly higher than those of the control. Whereas Cd contents were significantly higher in crayfish exposed to 125 μ g Cd 1 −1 , Cu contents were significantly lower in those receiving 62.5 μ g Cd 1 −1 . Antennal glands in Cd-exposed isopods contained approx. 5–8 times higher Cd, and 2–4 times lower Cu than those in the control. Differences in Zn contents of abdominal muscles and gills, Cd contents of abdominal muscles and exoskeleton and Cu contents of abdominal muscles, gonads and exoskeleton of the Cd-exposed crayfish were not significant at the 5% level. Similarly, Ni contents of antennal glands, gonads and hepatopancreas of the crayfish receiving 10–5000 μ g Ni 1 −1 ranged between 18.8 and 25.0, 3.2 and 16.3, and 4.0 and 6.7 μ g g −1 wet wt, respectively. Differences in Ni contents of abdominal muscles and alimentary canal, as well as Cu and Zn contents of the antennal glands, exoskeleton, gills and haemolymph between Ni-exposed and control crayfish were not significant at the 5% level. The study provides evidence of competition between Cd and Cu, and Ni and Cu. However, Zn stores of various tissues remained unaffected by the presence of either Cd or Ni.

Over the last decades, the populations of Austropotamobius pallipes have decreased markedly all over Europe. If we evaluate the ecological factors that determine its presence, we will have information that could guide conservation decisions. This study aims to investigate the chemical-physical demands of A. pallipes in NW Italy. To this end, we investigated 98 sites. We performed Principal Component Analysis using chemical-physical parameters, collected in both presence and absence sites. We then used principal components with eigenvalue > 1 to run Discriminant Function Analysis and Logistic Regression. The statistics on the concentration of Ca 2+ , water hardness, pH and BOD 5 were significantly different in the presence and in the absence sites. pH and BOD 5 played the most important role in separating the presence from the absence locations. These findings are further evidence that we should reduce dissolved organic matter and fine particles in order to contribute to species management and conservation.

The Freshwater Invertebrate Invasiveness Scoring Kit (FI-ISK) is proposed as a screening tool for identifying potentially invasive freshwater invertebrates. FI-ISK was adapted from the Fish Invasiveness Scoring Kit (FISK) of Copp, Garthwaite, and Gozlan, which is an adapted form of the Weed Risk Assessment (WRA) of Pheloung, Williams, and Halloy. Initial assessments using FI-ISK, which include confidence (certainty/uncertainty) rankings by the assessor to each response, were calibrated to determine the most appropriate score thresholds for classifying nonnative species into low-, medium-, and high-risk categories, using both the original medium-to-high risk threshold scores for the WRA (i.e., > or = 6) and for FISK (i.e., > or = 19). Patterns of the assessor's confidence, when making the responses during the FI-ISK assessments, were also examined. Using receiver operating characteristic (ROC) curves, FI-ISK was shown to distinguish accurately (and with statistical confidence) between potentially invasive and noninvasive species of nonnative crayfish (Decapoda: Astacidae, Cambaridae, Parastacidae), with the statistically appropriate threshold score for high-risk species scores being > or = 16. FI-ISK represents a useful and viable tool to aid decision- and policymakers in assessing and classifying freshwater invertebrates according to their potential invasiveness.

Many crayfish species have been introduced to novel habitats worldwide, often threatening extinction of native species. Here we investigate competitive interactions and parasite infections in the native Austropotamobius pallipes and the invasive Pacifastacus leniusculus from single and mixed species populations in the UK. We found A. pallipes individuals to be significantly smaller in mixed compared to single species populations; conversely P. leniusculus individuals were larger in mixed than in single species populations. Our data provide no support for reproductive interference as a mechanism of competitive displacement and instead suggest competitive exclusion of A. pallipes from refuges by P. leniusculus leading to differential predation. We screened 52 P. leniusculus and 12 A. pallipes for microsporidian infection using PCR. We present the first molecular confirmation of Thelohania contejeani in the native A. pallipes; in addition, we provide the first evidence for T. contejeani in the invasive P. leniusculus. Three novel parasite sequences were also isolated from P. leniusculus with an overall prevalence of microsporidian infection of 38% within this species; we discuss the identity of and the similarity between these three novel sequences. We also screened a subset of fifteen P. leniusculus and three A. pallipes for Aphanomyces astaci, the causative agent of crayfish plague and for the protistan crayfish parasite Psorospermium haeckeli. We found no evidence for infection by either agent in any of the crayfish screened. The high prevalence of microsporidian parasites and occurrence of shared T. contejeani infection lead us to propose that future studies should consider the impact of these parasites on native and invasive host fitness and their potential effects upon the dynamics of native-invader systems.

A collection of Cretaceous and Eocene specimens of decapod crustaceans from southern Vancouver Island, British Columbia, Canada, has yielded three new genera, Cowichianassa, Comoxianassa, and Preclarocarcinus, and four new species, Cowichianassa meckerti, Comoxianassa haggarti, Preclarocarcinus parvus, and Nitotacarcinus canadensis. The former two new species, each of which are callianassid ghost shrimp, display sexual dimorphism and are well-documented from major and minor claws as well as abdomina, unusual in the fossil record and especially unusual for Cretaceous forms. Nitotacarcinus was previously only known from the Eocene of Denmark ; thus, the new species extends its paleobiogeographic range dramatically. The beds in which the decapods were collected from the Paleogene Via Appia Beds were deposited in generally high-energy conditions favoring the formation of glauconite.

[Die Eier von A. pallipes sind am Weibchen durch einen spiraligen Funikulus befestigt, der bei der Eiablage gebildet wird. Bei seiner Enstchung kommt es zu einer Fusion der weichen Ausenschicht eines frish abgelegten Eies mit einer Gruppe von Borsten (Ooseten), die sich auf den Pleopoden und Sterna des Hinterleibs befinden. Seine endgultige Form erhalt der Funikulus in einer spaten Phase des Eiablagegeschehens., Die Eier von A. pallipes sind am Weibchen durch einen spiraligen Funikulus befestigt, der bei der Eiablage gebildet wird. Bei seiner Enstchung kommt es zu einer Fusion der weichen Ausenschicht eines frish abgelegten Eies mit einer Gruppe von Borsten (Ooseten), die sich auf den Pleopoden und Sterna des Hinterleibs befinden. Seine endgultige Form erhalt der Funikulus in einer spaten Phase des Eiablagegeschehens.]

1. 1. A lysozyme activity was found in four Astacidae and two Cambaridae species. 2. 2. Tested on Micrococcus luteus cell wall, the reaction was stable when heated in acidic buffer but heat labile in an alkaline one. 3. 3. The activity is present in serum, hemocyte lysate and plasma. 4. 4. In serum, the lysis occurred within the first 15 min; the less active was the plasma. 5. 5. In the six species, the kinetics followed the same pattern. 6. 6. Different animals of the same species exhibited a great variability in lysozyme activity: 32–53.8% of lysis after 1 hr in serum, 7–31.7% in plasma, and 20–50.3% in hemocyte lysate. 7. 7. Different stresses weakening the animals lowered the response to less than 25% of lysis after 1 hr instead of 60–86% in serum or 38–72% in hemocyte lysate. 8. 8. The lysozyme molecules seemed to be located in hemocytes and released during experimental cell lysate or in vitro coagulation. 9. 9. Plasma reaction could represent the background of the hemolymph activity occurring in natural conditions.

An introduction to the Freshwater Animal Diversity Assessment (FADA) project.- Global diversity of aquatic macrophytes in freshwater.- Global diversity of sponges (Porifera: Spongillina) in freshwater.- Global diversity of inland water cnidarians.- Global diversity of free living flatworms (Platyhelminthes, "Turbellaria") in freshwater.- Global diversity of rotifers (Rotifera) in freshwater.- Global diversity of nemerteans (Nemertea) in freshwater.- Global diversity of nematodes (Nematoda) in freshwater.- Global diversity of hairworms (Nematomorpha: Gordiaceae) in freshwater.- Global diversity of gastrotrichs (Gastrotricha) in fresh waters.- Global diversity of bryozoans (Bryozoa or Ectoprocta) in freshwater.- Global diversity of tardigrades (Tardigrada) in freshwater.- Global diversity of polychaetes (Polychaeta Annelida) in freshwater.- Global diversity of oligochaetous clitellates ("Oligochaeta" Clitellata) in freshwater.- Global diversity of leeches (Hirudinea) in freshwater.- Global diversity of freshwater mussels (Mollusca, Bivalvia) in freshwater.- Global diversity of gastropods (Gastropoda Mollusca) in freshwater.- Global diversity of large branchiopods (Crustacea: Branchiopoda) in freshwater.- Global diversity of cladocerans (Cladocera Crustacea) in freshwater.- Global diversity of ostracods (Ostracoda, Crustacea) in freshwater.- Global diversity of copepods (Crustacea: Copepoda) in freshwater.- Global diversity of fishlice (Crustacea: Branchiura: Argulidae) in freshwater.- Global diversity of mysids (Crustacea-Mysida) in freshwater.- Global diversity of spelaeogriphaceans & thermosbaenaceans (Crustacea Spelaeogriphacea & Thermosbaenacea) in freshwater.- Global diversity of cumaceans & tanaidaceans (Crustacea: Cumacea & Tanaidacea) in freshwater.- Global diversity of Isopod crustaceans (Crustacea Isopoda) in freshwater.- Global diversity of amphipods (Amphipoda Crustacea) in freshwater.- Global diversity of syncarids (Syncarida Crustacea) in freshwater.- Global diversity of crabs (Aeglidae: Anomura: Decapoda) in freshwater.- Global diversity of crabs (Crustacea: Decapoda: Brachyura) in freshwater.- Global diversity of shrimps (Crustacea: Decapoda: Caridea) in freshwater.- Global diversity of crayfish (Astacidae, Cambaridae, and Parastacidae-Decapoda) in freshwater.- Global diversity of water mites (Acari, Hydrachnidia Arachnida) in freshwater.- Global diversity of halacarid mites (Halacaridae: Acari: Arachnida) in freshwater.- Global diversity of oribatids (Oribatida: Acari: Arachnida).- Global diversity of springtails (Collembola Hexapoda) in freshwater.- Global diversity of mayflies (Ephemeroptera, Insecta) in freshwater.- Global diversity of dragonflies (Odonata) in freshwater.- Global diversity of stoneflies (Plecoptera Insecta) in freshwater.- Global diversity of true bugs (Heteroptera Insecta) in freshwater.- Global diversity of caddisflies (Trichoptera: Insecta) in freshwater.- Global diversity of dobsonflies, fishflies, and alderflies (Megaloptera Insecta) and spongillaflies, nevrorthids, and osmylids (Neuroptera Insecta) in freshwater.- Global diversity of water beetles (Coleoptera) in freshwater.- Global biodiversity of Scorpionflies and Hangingflies (Mecoptera) in freshwater.- Global diversity of non-biting midges (Chironomidae Insecta-Diptera) in freshwater.- Global diversity of craneflies (Insecta, Diptera: Tipulidea or Tipulidae sensu lato) in freshwater.- Global diversity of black flies (Diptera: Simuliidae) in freshwater.- Global diversity of mosquitoes (Insecta: Diptera: Culicidae) in freshwater.- Global diversity of dipteran families (Insecta Diptera) in freshwater (excluding Simulidae, Culicidae, Chironomidae, Tipulidae and Tabanidae).- Global diversity of butterflies (Lepidotera) in freshwater.- Global diversity of hymenopterans (Hymenoptera Insecta) in freshwater.- Global diversity of true and pygmy grasshoppers (Acridomorpha, Orthoptera) in freshwater.- Global diversity of fish (Pisces) in freshwater.- Global diversity of amphibians (Amphibia) in freshwater.- Global diversity of lizards in freshwater (Reptilia: Lacertilia).- Global diversity of crocodiles (Crocodilia, Reptilia) in freshwater.- Global diversity of turtles (Chelonii Reptilia) in freshwater.- Global diversity of snakes (Serpentes Reptilia) in freshwater.- Global diversity of mammals (Mammalia) in freshwater.- Global diversity of freshwater birds (Aves).- The Freshwater Animal Diversity Assessment: an overview of the results.

1. 1. Male and those female crayfish (Astacus astacus) not reproductively active during the previous autumn molt in early summer while egg bearing females do not molt until mid-summer after the young are released, in central Finland. 2. 2. Organic reserves in hepatopanceas (digestive gland) are much higher in premolt and intermolt males and previously non-reproductive females preparing to produce ova than premolt and intermolt females that were reproductively active during the preceding year. The percentages of moisture in the hepatopancreas and abdominal muscle range from 53–83% and 75–84%, respectively, in males and females depending on molt stage and reproductive status. 3. 3. Lipid, ash, crude protein, crude fat, crude carbohydrate, and total energy of hepatopancreas samples were approximately 15–20, 0.5, 0.5, 4–5, 1.0, and 1.0–1.5 times, respectively, the levels recorded in abdominal muscle samples. Ranges for hepatopancreas values were: 289–457 mg/g dry weight; 4. 3.7–4.8 g/100g; 24–36 g/100g; 44–63 g/100g; 6–19g/100g; and 2670–3150 kJ/100 g, respectively. 5. 4. The amount of mineral matter is similar in the intermolt (stage C) carapaces, dorsal abdominal terga, and chelae of males and females (73–79%) although chelae have 1–3% more mineral matter. Carapace mineral matter declines 5–10% during early phases of the premolt period (stage D).

The latest findings on the distribution of freshwater crayfish of the family Astacidae in Croatia were described.

The freshwater crayfish Austropotamobius torrentium collected in the Netherlands in 1956 (Crustacea: Decapoda: Astacidae) On 10 November 1956 a freshwater crayfish was collected in a fish trap in the canal that surrounds the polder Haarlemmermeer between Haarlem and Amsterdam about 2 to 3 km from the village Halfweg. The specimen is a fully grown male of 106 mm in total length; the left first cheliped is missing and the right first cheliped evidently has been lost previously, as a small regenerated cheliped (total length of cheliped 40 mm, length of chela 16 mm) is present. At that time Astacus astacus was the only freshwater crayfish in the Netherlands and the specimen was (incorrectly) identified as that species. As such it was also reported in Geelen’s (1978) discussion of the then known occurrence of freshwater crayfish in the Netherlands. The locality of the specimen was far outside the known Dutch region of occurrence of A. astacus. A recent re-examination of the specimen showed it not to be Astacus astacus, but Austropotamobius torrentium, which made the mystery of its locality only greater. Austropotamobius species have never been found in or near the Netherlands. Moreover, the habitat in which our specimen was found is so completely different from that in which that species usually lives, that its occurrence near Halfweg can only be artificial. How the specimen arrived there will always remain a puzzle. As the species is not a common aquarium animal, the aquarium trade is not likely to be the culprit.

Austropotamobius pallipes is a threatened species and a management plan must be put into action in order to avoid its extinction. As part of the recent conservation effort in Northern Italy, a phylogeographic and taxonomic study was deemed necessary. The sequencing of a 464 bp length of 16SmtDNA gene was used. The evolutionary topology and the parsimony network represented a well-structured separation into two clades. The genetic distance between clades was 4.78% (±0.71% SD) over the threshold for species distinction for the 16S mtDNA phylogenetic marker. A. pallipes and A. italicus were syntopic in the Po hydrographic basin while A. pallipes was only found in the Northwestern region (Piedmont) and a suture-zone was detected in the Apennine (Scrivia River) and Alpine (Sesia River) affluents. The haplotype and nucleotide diversity showed a similar composition of genetic variability. The phylogeographic findings distinguish two wild population stocks that have to be protected during in situ management decisions. © 2004 Published by Elsevier Ltd.

Branchiobdellidans of genus Branchiobdella Odier, 1823 have been scarcely studied in Croatia and there is almost no data on them recorded in literature. In order to improve the general knowledge on the occurrence of the various species of branchiobdellidans on freshwater crayfish in Croatia, we collected branchiobdellidan specimens from our crayfish collection. This study includes native and alien crayfish species distributed within Croatia: Astacus astacus, Astacus leptodactylus, Austropotamobius pallipes, Austropotamobius torrentium, and Orconectes limosus. Branchiobdellidans were determined from 41 different crayfish populations. In this research the following branchiobdellidan species were identified: Branchiobdella parasita, B. pentodonta, B. balcanica, B. hexodonta and B. italica.

Rak kamenjar (Austropotamobius torrentium) je najmanja vrsta porodice Astacidae o čijoj se ekologiji, biologiji i životnom ciklusu ne zna dovoljno. Stoga je svrha istraživanja bilo sakupljanje podataka o reprodukcijskom ciklusu ove vrste. Važan čimbenik koji utječe na fekunditet ženki je veličina jaja. Zna se da se s povećanjem veličine jaja smanjuje fekunditet, no nije poznato kakav je odnos između veličine jaja i veličine ženki pa smo u ovom radu istražili taj odnos. Istraživanje je provedeno od listopada 1998. do travnja 2000. godine u potocima Medvednice. Ukupno je ulovljeno 767 ženki, od čega su 92 (11, 99 %) imale jaja pričvršćena za pleopodalne noge. Vanjska jaja su na ženkama pronalažena od početka studenog do sredine lipnja slijedeće godine. Najmanja ulovljena ženka s pleopodalnim jajima je bila ukupno duga (od vrha rostruma do kraja telzona) 5.4 cm, a najveća 9, 29 cm. Promjer pleopodalnih jaja kretao se od 0, 24 do 0, 36 cm (srednja vrijednost = 0.28 +- 0, 02), a njihov broj po ženki od 1 do 104. Zabilježena je pozitivna korelacija između veličine ženki i broja jaja (r = 0, 39) veličine ženki i promjera jaja (r = 0, 30) te negativna između broja jaja i njihovog promjera (r = -0, 04). Do sada su u procjeni fekunditeta, odnosno prirasta u populaciji, korišteni odnosi veličine ženki i broja jaja, a dobivene spoznaje o pozitivnoj korelaciji između veličine ženki i veličine, tj. promjera jaja, ukazuju da se i ovaj odnos može koristiti za preciznije procjenjivanje fekunditeta i prirasta.

Psorospermium haeckeli is a thick-walled unicelular organism widely reported in European astacid crayfish. Its taxonomic status has recently being elucidated, it is closely related to the similar organisms of aquatic pathobiology and they all consist DRIP clade which is near the animal-fungal divergence. Psorospermium haeckeli is considered as a &laquo ; ; ; parasite&raquo ; ; ; although its pathogenic impact still remaines unclear. Untill now there were no data about its presence in Croatian astacid crayfish. We examined 119 specimens of the three astacid species from 10 different locations and found sporocysts of the Psorospermium haeckeli in 7 preparations of epidermal-connective tissue of Astacus astacus and A. leptodactylus. Preparations were made by scraping the epidermal-connective tissue from under the carapace, treating it with 10% KOH and viewing it under the microscope at 120 x magnification. Relative scale was used to describe the degree of infection of the crayfish by P. haeckeli. We found only the mature form of Psorospermium haeckeli. The sporocyst was quite long and narrow and was sourounded by three layers: innermost membranous layer ; the cell wall which is well formed, thick and consists of numerous plates and, barely visible, but fully developed outermost gelatinous layer. Psorospermium sporocyst contained a few large globules and many small ones or sometimes was filled with only small uniform globules. In the A. leptodactylus we found many sporocysts which were fully melanised. Further investigations are needed to understand distribution of infected crayfish in Croatia and patterns of their infection with Psorospermium.

Worldwide, about 500 species of freshwater crayfish are known. Europe has only five, all of which belong to a single family, Astacidae, with two genera: Astacus astacus, A. leptodactylus and A. pachypus, and Austropotamobius pallipes and A. torrentium. The widespread elimination of native populations by crayfish plague, Aphanomyces astaci, and human intervention has led to the introduction of plague-resistant North American crayfish in an effort to restore Europe’s once highly profitable crayfish industry. Crayfish have also been imported to occupy a vacant niche, for aquaculture purposes, and for home aquariums and ornamental pools. The main alien species established in Europe are two cambarids, Orconectes limosus (introduced in the 1890s, currently in 15 countries) and Procambarus clarkii (1970s, 11 countries), and one astacid, Pacifastacus leniusculus (1960s, 25 countries). Recently, Orconectes immunis and Procambarus zonangulus have been released into natural waters in Germany. The main benefits of introductions have been new productive fishery in plague-stricken waters, new opportunities for crayfish culture and an additional source of food. The socio-economic aspects and recreational values are also important. The most disastrous impact has been on native crayfish populations. Alien species can be vectors of the plague fungus and thus present a persistent risk to native species. The fact that these species are highly competitive alien species — even without the plague — gives rise to detrimental competition and eventually replace native species when sympatric. Despite the increasing interest in conserving Europe’s unique native crayfish fauna and its biodiversity, the threat of crayfish plague, habitat changes, continuous expansion of the ranges of alien species by human activity and the removal of trade barriers hamper efforts to ensure the future of indigenous species.

International audience

Knowledge of the molting cycle in crayfish may contribute (1) to improving a population analysis for monitoring and conservation purposes and (2) to imposing significant constraints on practices involved in culture. Two populations of Austropotamobius pallipes in central Italy were monitored from April to November for five years (2002–2006). Crayfish were collected, sexed, and the carapace length (CL) was measured. Molt cycle stages (premolt, molt, postmolt and intermolt) were identified depending on the exoskeleton hardness and color, and the abdomino-thorax splitting. The molt lasted for 6 minutes in juveniles, and maximally 16 minutes in adults in captivity. Males and females were treated separately, and divided into five age classes (0+; 1+; 2+; 3+; >4+). No significant differences were observed between females and males of the same age class. The molting event mainly occurred in April and May ongoing to November. The molting cycle occurred less frequently between July and August, and during the study period it was rarely observed between the last five days of July and the first week of August. Moreover, we measured and counted the gastrolith layers from a total of 124 crayfish (73 females + 51 males) collected twelve years ago, in order to discuss possible correlations between CL and gastrolith size.

Considering the concerns about the safety of the use of formaldehyde as antifungal agent, the effects of three alternative chemicals (potassium sorbate, copper hydroxide and magnesium chloride) were tested in the artificial incubation of signal crayfish (Pacifastacus leniusculus ) eggs. Eight treatments were performed during 15 min every other day: formaldehyde at 3000 ppm (control), potassium sorbate at 5000 and 10000 ppm, copper hydroxide at 40, 60, 80 and 200 ppm, and magnesium chloride at 10000 ppm. Eggs were incubated in a flow through system at a density of 20 eggs·cm−2 . After 61 days of incubation, the highest efficiencies were obtained with 200 ppm of copper hydroxide (77.6% of survivors to stage 2) with no significant differences from the control (74.3%). Lower concentrations of copper hydroxide resulted in high egg mortality whereas potassium sorbate and magnesium chloride were ineffective to avoid fungal growth and total egg mortality took place. From the obtained results, copper hydroxide baths at 200 ppm could be considered as a good alternative to formaldehyde.