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Los leptostráceos de las costas occidentales de la península Ibérica han sido comparativamente mejor estudiados que los de las mediterráneas en los últimos años. En este trabajo se reporta por primera vez la presencia de Nebalia troncosoi Moreira, Cacabelos & Domínguez, 2003 en las costas del Mediterráneo ibérico a partir de ejemplares recogidos en 2014 frente al Delta del Ebro. El material examinado coincide con la descripción original de la especie, que está caracterizada por presentar un rostro largo (cuatro veces más largo que ancho), un caparazón corto en relación a su altura, el cuarto artejo del pedúnculo de la anténula con una única espina distal, el flagelo antenular más corto que el pedúnculo y compuesto por 6–7 artejos, el exopodio de la maxilla II más largo que el primer artejo del endopodio, el borde dorsal y posterodorsal de los pleonitos VI–VII con dentículos agudos y las escamas anales sin una meseta definida en el borde medial.

Three leptostracan species (Crustacea: Phyllocarida) are reported from mud volcanoes at the Moroccan margin of the Gulf of Cadiz (NE Atlantic). Nebalia strausi Risso, 1826 and N. abyssicola Fage, 1929 were found in experimentally deployed organic substrates in Mercator, Meknès and Darwin mud volcanoes; N. abyssicola was also found among bathymodiolin bivalves and is recorded for the first time in the Atlantic Ocean. The third species was collected from the Gemini mud volcanoes and is described herein as Sarsinebalia ledoyeri sp. nov. The new species is characterised by having the eyes provided with ommatidia and lacking pigment, the ventral margin of the eye is concave along distal half, the antennular scale is more than twice as long as wide, the second article of the mandibular palp bears one seta on lateral surface about 0.5 times as long as the article and one subterminal seta longer than the third article, the distal article of the maxilla II endopod is about 1.8 times as long as the proximal article, the maxilla II exopod is clearly longer than the endopod proximal article, the lateral margin of the pleopod I exopod lacks setae and the posterodorsal border of pleonites VI–VII is provided with rounded to pointed denticles.

The marine ecosystem of the Chilean Patagonia is considered structurally and functionally unique, because it is the transition area between the Antarctic climate and the more temperate Pacific region. However, due to its remoteness, there is little information about Patagonian marine biodiversity, which is a problem in the face of the increasing anthropogenic activity in the area. The aim of this study was to analyze community patterns and environmental characteristics of scavenging crustaceans in the Chilean Patagonian Sea, as a basis for comparison with future situations where these organisms may be affected by anthropogenic activities. These organisms play a key ecological role in marine ecosystems and constitute a main food for fish and dolphins, which are recognized as one of the main tourist attractions in the study area. We sampled two sites (Puerto Cisnes bay and Magdalena sound) at four different bathymetric strata, recording a total of 14 taxa that included 7 Decapoda, 5 Amphipoda, 1 Isopoda and 1 Leptostraca. Taxon richness was low, compared to other areas, but similar to other records in the Patagonian region. The crustacean community presented an evident differentiation between the first stratum (0–50 m) and the deepest area in Magdalena sound, mostly influenced by Pseudorchomene sp. and a marked environmental stratification. This species and Isaeopsis sp. are two new records for science. The discovery of undescribed species evidences that this region needs further studies exploring its biodiversity, which is most likely being already impacted by anthropogenic pressure. [ABSTRACT FROM AUTHOR]

A new species of Leptostraca, Nebalia tagiri sp. nov. is described and illustrated. This species was sampled from 200 m depth at a hydrothermal field in Wakamiko Caldera of Kagoshima Bay, Japan. Nebalia tagiri sp. nov. is different from known Nebalia species as follows: rostral length 2.4 times as long as width; article 4 of antennule with 3-5 robust distal spines; antennular scale approximately twice as long as wide; article 3 of antenna with eight spines and nine spine-like setae along proximal half, two thin setae and six spine-like setae on external lateral face, six spines and four simple setae on distal margin; article 1 of second maxilla longer than article 2; article 2 of mandibular palp with two thin setae; exopod of pleopod 1 with 21 spines along lateral margin; furcal rami longer than combined length of pleonite 7 and telson; rounded denticles of pleonite 6 and 7; anal-plates 'shoulder' not distinct. Furthermore, this specimen is the first genus Nebalia found in the hydrothermal vent. The distribution and ecology of this new species is also discussed and a key to all species of Nebalia is provided. [ABSTRACT FROM AUTHOR]

An exceptionally preserved biota is described from the middle Telychian (Llandovery, Silurian) Fentou Formation of Wuhan, Central China, which preserves nontrilobite arthropods, cnidarians, echinoderms, sponges, fish, and algae as well as abundant shelly fossils and trace fossils in the Skolithos-Cruziana ichnofacies. This biota can be divided into two assemblages on the basis of the biological characteristics, fossil-bearing strata, and their sedimentary environments. Assemblage 1 comprises nonbiomineralized phyllocarids, Sphenothallus, conulariids, complete crinoids and stelleroids, and Burgess Shale-type sponges as well as some uncertain fossils in taxonomy and abundant marine shelly fossils. Assemblage 2 consists of numerous eurypterids, agnathans, chondrichthyes, and a few conulariids, algae, as well as shelly euryhaline fossils. Discoveries of the Fentou biota expand the temporospatial distribution and sedimentary environment of the exceptionally preserved Silurian biota and advances a deeper understanding of the biological assemblage and ecological system in the Llandovery. It also provides new data for studying the biological recovery and radiation under the background of the littoral sea (assemblage 1) and estuary-delta (assemblage 2) environments after the latest Ordovician mass extinction. [ABSTRACT FROM AUTHOR]

Cascolus ravitis gen. et sp. nov. is a three-dimensionally preserved fossil crustacean with soft parts from the Herefordshire (Silurian) Lagerstätte, UK. It is characterized by a head with a head shield and five limb pairs, and a thorax (pereon) with nine appendage-bearing segments followed byan apodous abdomen (pleon). All the appendages except the first are biramous and have a gnathobase. The post-mandibular appendages are similar one to another, and bear petal-shaped epipods that probably functioned as a part of the respiratory-circulatory system. Cladistic analysis resolves the new taxon as a stem-group leptostracan (Malacostraca). This well-preserved arthropod provides novel insights into the evolution of appendage morphology, tagmosis and the possible respiratory-circulatory physiology of a basal malacostracan. [ABSTRACT FROM AUTHOR]

Nebalia dolsandoensis sp. nov. (Malacostraca: Phyllocarida: Leptostraca), is described from specimens taken from light traps in harbours with organic-rich muddy sand and seaweeds along the south coast of Korea. The new species is characterized based on the following unique combination of characteristics: an antennular flagellum with up to only nine articles in the mature female; the fourth article of the antennule has up to four distal spine-like setae; pleonites 3–7 have rounded denticles along the posterior dorsal margins; the protopod of pleopod 4 has an even posterior margin; the uropods are distinctly short, about 0.6 times as long as pleonite 7 and the anal somite combined; the anal plates have a noticeably broad lateral ‘shoulder’. In addition, a key to the species of the genus Nebalia Leach, 1814 and partial sequences of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene from the new species are provided. [ABSTRACT FROM PUBLISHER]

Paranebalia longipes (Willemoes-Suhm, 1875) is cosmopolitan and has been usually found in the algal and sponge debris on the sandy mud substrates. This species can be clearly distinguished from other species of Paranebalia by the presence of serration on posterior margin of pleopods, the number of articles on antennule and antenna, and number of teeth on flange of antennule fourth article. The genus Paranebalia is new to Korea. In this paper, we provide detail descriptions of the diagnostic characteristics and illustrations of the P. longipes. Additionally, type locality and world distribution of the genus Paranebalia are provided.

Knowledge on taxonomy and ecology of leptostracan crustaceans is still scarce in many parts of the world. Sampling in subtidal sediments in the Ria of Ferrol (NW Spain) between 2006 and 2007 yielded several leptostracan specimens belonging to six species. This is, so far, the largest number of leptostracan species reported from a single area. Some specimens belong to an undescribed species of Nebalia Leach, 1814, which is described herein as N. reboredae n. sp. The new species has a rostrum about 2.2 times as long as wide, the antennular scale is slightly more than twice as long as wide, the fourth article of the antennule has one short thick distal spine, the first article of the endopod of the second maxilla is 1.3 times as long as the second one, the exopod of the second maxilla is longer than the first article of the endopod, the posterior dorsal borders of pleonites 5-7 are provided with distally rounded to truncated denticles, and the uropods are as long as pleonite 7 and the anal somite combined. All the species collected are reported, including the number of specimens, sexual condition and substrate type. A key to all known neritic species of the Iberian Peninsula is provided.

The article discusses collecting and processing leptostracans. It mentions that leptostracans are distinguished from other crustaceans by the presence of several key anatomical features. It mentions leptostracans are represented by 10 genera and 43 nominal species. It mentions that Leptostracans can be distinguished from similar-sized crustaceans such as gammaridean amphipods.

A new species of Leptostraca, Nebalia terazakii sp. n. is described and figured. The species was sampled from the coral reefs of Pulau Payar Marine Park, Langkawi, Malaysia. There are 32 existing species of Nebalia but Nebalia terazakii sp. n. can be distinguished from the other known species of Nebalia by the following combination of characters: the rostrum is 1.89 times as long as wide and the eyes have no dorsal papilla or lobes. Article 4 of the antennular peduncle has one short thick distal spine. The proximal article of the endopod of maxilla 2 is shorter than the distal, a feature peculiar to Nebalia terazakii sp. n., the exopod of maxilla 2 is longer than article 1 of the endopod, the posterior dorsal borders of the pleonites 6 to 7 are provided with distally sharp denticles, anal plate with prominent lateral shoulder and finally, the terminal seta of the caudal rami is 1.17 times the length of the entire rami. [ABSTRACT FROM AUTHOR]

Phyllocarids of the Waukesha Biota were systematically and taphonomically evaluated. Three Ceratiocaris species are present in the biota: C. macroura Collette and Rudkin, 2010; C. papilio Salter in Murchison, 1859; and C. pusilla Matthew, 1889. Specimens range in completeness from nearly complete, including the cephalic to caudal regions, to isolated telsons and furcae. Evidence of Salter’s position is present in only three specimens. Relatively complete specimens are interpreted to represent corpses, rather than molts; whereas specimens including only the pleon and caudal region, or caudal region, and specimens with evidence of Salter’s position likely represent exuviae. Specimens are preserved essentially as compression fossils exhibiting two types of preserved cuticle: brown inner cuticle, which tends to be impressed over the topography of bedding planes on which specimens are preserved, and blue-gray phosphatized cuticle exhibiting sub-millimeter scale relief. Cuticle phosphatization likely occurred during early diagenesis. The presence of characteristic near-shore species and C. pusilla, only known from turbidite facies, interpreted to possibly represent a marine trough, suggests that the Waukesha phyllocarid assemblage might represent a transported assemblage, rather than a biota, or that C. pusilla from the Jones Creek Formation was transported basinward in sediment gravity flows. [ABSTRACT FROM AUTHOR]

A new specimen of a basal echinocaridid phyllocaridan is noted from the Lower Devonian sediments of the Izdebno IG-1 borehole of central-eastern Poland. The description and reconstruction are based on a three-dimensionally preserved incomplete left carapace valve. The unique characters of the valve surface, mainly in the form of the number and location of nodes, places this specimen within Ptychocaris. However, the unique arrangement of nodes on its carapace allows us to erect a new species, Ptychocaris sheldoni n. sp. The parallel and longitudinal ridges ('striae') preserved on the carapace suggest the ability of a fast burial into the muddy seafloor. [ABSTRACT FROM AUTHOR]

Thylacocephalans are an extinct group of arthropods of an uncertain systematic position. Originally considered phyllocarid crustaceans, they have since been classified within their own class, the Thylacocephala Pinna, Arduini, Pesarini and Teruzzi, 1982 on the basis of the exceptionally preserved Lower Jurassic (Sinemurian) species Ostenocaris cypriformis from Osteno, Italy. Since that time, the membership of the Thylacocephala has grown as a number of new species have been discovered, as well as previously known species moved into the group. [ABSTRACT FROM AUTHOR]

Although there is a relatively robust fossil record of archaeostracan phyllocarids, preserved antennulae and antennae are rare. Few examples have been described. A review of archaeostracans with preserved antennulae and antennae is provided, as well as a description of a specimen of Ceratiocaris cf. macroura Collette and Rudkin, 2010, with preserved antennae, and a detailed description of a specimen of Ceratiocaris papilio Salter inMurchison, 1859, from the Silurian of Scotland. The presence of antennulae with two subequal length rami in Rhinocaridina and Echinocaridina supports previous assertions that possessing biramous antennulae is a malacostracan synapomorphy. An antennal scale in Ceratiocaris, in contrast to those of Rhinocaridina and Echinocaridina, but consistent with eumalacostracans, suggests that ceratiocarids could represent stem eumalacostracans. Hooked antennae in C. papilio, similar to copulatory clasping antennae of Nebaliopsis typica G. O. Sars, 1887, are interpreted to represent the earliest evidence of sexual dimorphism in malacostracans. [ABSTRACT FROM AUTHOR]

Nahecaris balssiBroili, 1930 is a phyllocarid crustacean known only from the Lower Devonian Hunsrück Slate in Germany. This study redescribes the species on the basis of 22 new specimens and the holotype. Phylogenetic analysis of several Palaeozoic phyllocarids reveals thatN. balssiandN. stuertziJaeckel, 1921 are not congeneric, as was previously assumed, and that there are significant morphological differences between these taxa. Thus, the new genusOryctocarisis erected forN. balssi, characterized mainly by the absence of a rostrum and a median dorsal plate. It is suggested thatO. balssiwas a fairly active swimmer, which was not limited to the benthic zone. Furthermore, the species presumably swam by means of powerful pleopod strokes coupled with downward movements of the abdomen. It is likely the telson spine with its furcal rami acted as a paddle, enhancing propulsion. We suggest thatO. balssiwas a deposit feeder, foraging by digging in the mud and picking up food particles or small hard-shelled organisms such as molluscs, which were then crushed by the large and robust mandibles. http://zoobank.org/urn:lsid:zoobank.org:pub:7A84A8A9-F9F3-464E-A3B2-24B9056EE0B6 [ABSTRACT FROM AUTHOR]

Abstract: In recent years, there has been a growing interest in synthesizing studies on the structure of the nervous systems with phylogenetic questions (“neurophylogeny”). However, in the discussion on the phylogeny of Malacostraca, and the question of their closest relatives, little attention has been paid to brain morphology in the basal representatives of this taxon. To close this gap in our knowledge, this study sets out to analyze the architecture of the brain of Nebalia herbstii (Leptostraca, Phyllocarida, Malacostraca) in a neurophylogenetic context. Most phylogenetic studies consider the Phyllocarida to be the sister group to the Eumalacostraca, together forming the taxon Malacostraca, so that the brain organization of N. herbstii may possess many ancestral features. Classical histological techniques and 3D reconstruction as well as immunostaining and confocal laser-scan imaging revealed that besides taxon specific characteristics, the brain organization of N. herbstii exhibits a strong eumalacostracan affinity. The four nested optic neuropils are connected by two successive chiasms. The olfactory globular tract, connecting the olfactory lobes with second order integration centers in the lateral protocerebrum, features a contralateral connection. The olfactory lobes are composed of a radial array of spherical/spheroid glomeruli but serotonergic innervations of the olfactory glomeruli are absent. These and other architectural features are discussed in comparison to the central nervous system of Eumalacostraca, Remipedia, non-malacostracan Crustacea and Hexapoda, and are synthesized into a ground pattern of the malacostracan brain that might serve as a basis for neurophylogenetic discussion of the evolutionary relationship of these taxa. [Copyright &y& Elsevier]

Herein, we report a new species of leptostracan, Nebalia koreana (Malacostraca) collected from the southern and eastem coasts of the Korean peninsula. All the specimens of this species were collected by means of light traps from harbors where the bottoms are sandy and with algal mats. The new species differs from all other known Nebalia in the following characters: the carapace is relatively small, and covers the lateral sides of pleonite 2 and partially the lateral sides of pleonite 3; the fourth article of the antennule has up to five short distal spines; pleonites 3 to 7 have rounded denticles along the posterior dorsal borders; the epipod of thoracopod 7 bears 5 to 6 plumose setae along the posterior margin, which are lacking on the remaining thoracopods; and the protopod of pleopod 4 lacks serration along the posterior border. Only two species of Nebalia have been reported from the tropical or subtropical seas of Asia. Therefore, the new species is the first species of Nebalia found in the temperate zone of Asia. Additionally, type localities and world distribution of the genus Nebalia are provided in this paper. [ABSTRACT FROM AUTHOR]

Data on deep sea leptostracans (Crustacea: Phyllocarida: Leptostraca) are still scarce in many parts of the world. In the last few years, several species of Nebalia Leach, 1814, have been reported from the eastern Mediterranean; however, there have been no reports from waters deeper than 100 m. Samples collected recently from Gökçeada, Turkey--at depths of 680-820 m in the Aegean Sea, eastern Mediterranean--included Nebalia abyssicola Fage, 1929. This is the first record for the study area and one of the few known records of this species. Specimens are described and figured to complement previous descriptions. A key for all known leptostracans from the eastern Mediterranean is also provided. [ABSTRACT FROM AUTHOR]

Nebalia deborahae new species is described from samples collected in coastal shelf zones off Namibia and Angola, in 2004 and 2008. The genus Nebalia is now represented in West and South Africa by three species. The new species differs from other African species in the length/width ratio of the rostrum, in the armature of the fourth segment of the antennule, in the dentation on the dorsal side of pleonites 6 and 7, and in the shape of the posterolateral corner of the epimeron of the fourth pleonite. [ABSTRACT FROM AUTHOR]

Phyllocarids (Crustacea: Malacostraca) from the Upper Devonian (Givetian-Frasnian) Gogo Formation of Western Australia are described and two new species are reconstructed. The mineralized exoskeleton is well preserved in concretions, but the appendages, apart from the mandible, are unknown. Montecaris gogoensis sp. nov. (Echinocarididae) is represented by >600 specimens; a possible second species of Montecaris is represented only by ∼14 specimens of antero-dorsal fragments of the valves, which are highly tuberculate. Schugurocaris wami sp. nov. (Ceratiocarididae) is represented by >300 specimens; a possible second species with a very elongate telson is represented by four specimens. An undetermined species of Dithyrocaris (Dithyrocarididae) is represented by >80 specimens. [ABSTRACT FROM AUTHOR]

Sampling studies on the Turkish Mediterranean coast revealed the presence of two species of Leptostraca belonging to the genus Nebalia. These species were identified as N. strausi Risso, 1826 and N. kocatasi Moreira, Kocak & Katagan, 2007. The presence of the two species is reported for the first time from the region; these records therefore further extend the known distribution of these species from the Aegean Sea to the Turkish waters of the Mediterranean Sea. A checklist of all known leptostracans from the Mediterranean Sea is provided. [ABSTRACT FROM AUTHOR]

A phylogenetic analysis and review of Paleozoic phyllocarid systematics is presented using morphology-based characters from Cambrian to modern taxa. The resulting cladograms of the Phyllocarida suggest that the suborder Ceratiocaridina as traditionally defined (families Ceratiocarididae and Caryocarididae) is paraphyletic. Caryocarididae is subsequently elevated to subordinal rank with the erection of Caryocaridina n. suborder, resulting in two monophyletic suborders. Haplocaris n. gen. is erected to contain Caryocarididae taxa without triangular spine-like projections of the anterior telson margin. Emended diagnoses, quantified with morphometrics where appropriate, are integrated into this analysis, and result in synonymy of many Cambrian-Silurian caryocaridids and ceratiocaridids with pre-existing taxa. Two representatives of the Leptostraca are included in this analysis. A visual key of well-established representatives of the Ceratiocaridina is presented and suggestions are offered that will help to improve the long-term stability of the Archaeostraca. [ABSTRACT FROM AUTHOR]

Three new types of arthropod are described from Cambrian intertidal lithofacies of the Elk Mound Group and St. Lawrence Formation of Wisconsin and the Potsdam Group of Quebec. These arthropods are preserved ventrally in sandstone in life position and in three dimensions, allowing detailed characterization of limb morphologies, labrums, and other organs such as eyes. A taphonomic model is presented, illustrating this unusual, uncompressed, three-dimensional style of preservation. Arenosicaris inflata n. sp., from the Terreneuvian-Furongian Elk Mound Group and the Furongian St. Lawrence Formation, is the earliest unambiguous occurrence of a malacostracan phyllocarid. This 3 cm long arthropod had ovate valves, five pairs of biramous pleopods, and at least 3 pairs of thoracopods. Mosinieia macnaughtoni n. sp., a large (>10 cm long) euthycarcinoid of uncertain affinity with flattened or paddle-like appendages also occurs in Elk Mound strata. Mictomerus melochevillensis n. sp. represents a new euthycarcinoid family and is the first known non-trilobite arthropod from the middle Cambrian-Furongian Potsdam Group of Quebec. M. melochevillensis n. sp. is large (8-10+ cm long), with as many as eleven pairs of well-preserved homopodous, uniramous, non-paddle-like limbs. Both M. macnaughtoni and M. melochevillensis differ substantially from previously known euthycarcinoids in limb morphology and represent the oldest known representatives of the group. Additionally, both M. melochevillensis n. sp. and M. macnaughtoni n. sp. possess morphologies that are consistent with abundant subaerial and subaqueous Diplichnites and Protichnites trackways known from these units, suggesting that these may be the earliest land-going animals. [ABSTRACT FROM AUTHOR]

Knowledge about leptostracans from the Mediterranean Sea is still scarce. Examination of samples collected from the Aegean Sea off Turkey and from Cyprus in the eastern Mediterranean Sea revealed new localities and range extensions for 2 species of leptostracans: Nebalia strausi Risso, 1826, and N. kocatasiMoreira, Koçak, and Katagan, 2007. The record of N. kocatasi is the first for Cyprus and for the Levantine Basin. Additional specimens (Nebalia sp. 1 and Nebalia sp. 2) might prove to belong to 2 new species but the lack of material prevents their formal description. [ABSTRACT FROM AUTHOR]

Two species of well-preserved phyllocarid crustaceans, Ceratiocaris macroura n. sp. and Ceratiocaris papilio Salter, occur in the Eramosa Formation Lagerstãtte of Ontario, Canada, represented by several dozen articulated fossils preserving limbs and thoracic segmentation. Ceratiocaris macroura n. sp. is distinguished by possession of an exceptionally elongate telson in relation to its body length. Ceratiocaris papilio preserves fine detail of the abdominal scale-like ornamentation, allowing reinterpretation and enhanced characterization of this key feature. Ceratiocaris papilio has a wide paleogeographic distribution across Laurentia but is restricted to shallow marine depositional settings within the middle Silurian. [ABSTRACT FROM AUTHOR]

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Nebalia straus Risso, 1827 (Phyllocarida, Leptostraca) is reported for the first time from the Cypriot coast and Levantine Sea. Specimens were collected at two sampling stations at depths between 0 and 5 m on northern Cyprus in July 1998. Morphological features of these specimens and information about the distribution of N. straus are provided. [ABSTRACT FROM AUTHOR]

A new record of the leptostracan, Nebalia straus Risso, 1827 (Phyllocarida, Leptostraca) is reported from specimens collected at two sampling stations in Izmir Bay, Aegean Sea coast of Turkey between 2001 and 2002. The species is characterized by having a long antennular flagellum that bears up to 11-12 articles (in mature females), a long antennular scale 2.5 times as long as wide, a second maxilla with an exopod slightly longer than the first article of the endopod, and a stout distal spine on the fourth article of the antennule (two in ovigerous females). N. straus is recorded here for the first time from the eastern Mediterranean. [ABSTRACT FROM AUTHOR]

The feeding ecology of leptostracans is not well-known. In the present study, species of Nebalia (Crustacea: Leptostraca) were captured every month for 1 year from Lobster Bay, Hong Kong, using baited traps. Captured individuals fell into a size range of 0.36–3.64 mm and 0.95–5.52 mm in carapace and total lengths, respectively. They were divided into different reproductive stages based on the morphology of the second pair of antennae and thoracopods. Sexual dimorphism becomes apparent between 0.7–1.5 mm (CL) and 1.4–3.2 mm (TL). Most individuals collected were sexually differentiated, but immature (79.7% of the captured individuals), followed by post-ovigerous (11.4%) and ovigerous (8.9%) females. Sexually undifferentiated juveniles were rare (3.9%). The sex ratio of the immature individuals approached 1:1 with a propensity towards male dominance. Not one mature male was captured. Although females with setose thoracopod endopods, indicating that they were ovigerous, were captured frequently, only two were carrying eggs. The two brooding females had clutch sizes of 11 and 17 eggs. Alternate peaks in relative abundance of ovigerous and post-ovigerous females were identified, the latter following the former. Reproductive activities occurred mainly in April–May and October–December, indicating that two cohorts are recruited. Catches using baited traps could be explained by the reproductive season of Nebalia sp. High catches were usually associated with the months of highest reproductive activity, low catches with peaks in post-ovigerous females. It is therefore concluded that not all individuals at various reproductive stages are attracted to carrion and hence adopt a scavenging feeding mode. Catches of Nebalia sp. in Hong Kong possibly reflect their annual cycle of reproductive activity [ABSTRACT FROM AUTHOR]

A mass occurrence of schooling, weakly sclerotized eocaridid shrimps in the Early Devonian pelagic environment of northern Russia suggests that the body-plan of the Eumalacostraca originated as an adaptation to swimming in the open sea. They probably replaced their ecological analogues, the archaeostracan phyllocarids Caryocaris, as a consequence of the rebuilding of the global marine environment during the later Ordovician. This may explain the rarity of the eumalacostracans in the Devonian and the difficulty with documenting their links with the archaeostracans. The new eocaridid shows similarities to the Carboniferous Anthracophausia in the general appearance and weak sclerotization of the carapace and appendages, but lacks its derived characters. The morphology of the pleural lobes, which have minute spines, is the only identified distinguishing character of the proposed new genus and species Archangeliphausia spinosa gen. et sp. nov. Its carapace was probably firmly connected dorsally with the thoracic segments. The only associated fossils of the assemblage represent a bizarre archaeostracan Pechoracaris aculicauda gen. et sp. nov., with a weakly sclerotized carapace lacking any hinge or rostral plates but with reduced furca, an extremely long caudal spine and pleopods transformed into spines. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 142, 83–90. [ABSTRACT FROM AUTHOR]

From the fluvial Old Red Sandstone (ORS) of the Lower to Middle Devonian Wood Bay Formation (NW-Spitsbergen), a diverse trace fossil assemblage, including two new ichnotaxa, is described: Svalbardichnus trilobus igen. n., isp. n. is interpreted as the three-lobed resting trace of an early phyllocarid crustacean (Rhinocarididae). Cruziana polaris isp. n. yields morphological details that point towards a trilobite origin. This occurrence of presumably marine trace makers in a fluvial red bed sequence raises the question of whether we are dealing with marine ingressions that are not sedimentologically expressed, with homeomorphy, or with an adaptation of marine groups to non-marine environments. [ABSTRACT FROM AUTHOR]

Reevaluation of 21 specimens of Permian crustaceans from near Palermo, Italy, referred to Palaeopemphix Gemmellaro, 1890, has resulted in transfer of the genus from the decapod Crustacea to a new suborder, the Palaeopemphida, and a new superfamily, Palaeopemphidae, of the archaeostracan Phyllocarida. [ABSTRACT FROM AUTHOR]

Saronebalia guanensis, a new genus and species of leptostracan, is described from material discovered in shallow subtidal waters of Guana Island, British Virgin Islands. The specimens were collected from light traps placed on sediment and by hand from the green alga Halimeda. Saronebalia differs from other leptostracans most notably in the morphology of the antennule and the eighth thoracic limb; the articles of the antennular flagellum are fused and bear dense clusters of setae, and the eighth thoracic limb is elongate. While its eyes, like those of Nebalia, are nontuberculate, it shares the rostral spine, dentate process of antennular article 4, and serrate pleopodal protopods of Levinebaila and Paranebalia. Specimens of the new genus lack the setal row of the exopod of pleopod I, a complex feature characteristic of Dahlella, Levinebaila, Nebalia and Paranebaila. A cladistic analysis of the 10 leptostracan genera, using 30 morphological characters from these features and others, also supports the status of Saronebalia as a new genus. Saronebalia represents the third leptostracan genus to be recorded from the Caribbean Sea. [ABSTRACT FROM AUTHOR]

Two new species of Leptostraca (Crustacea, Malacostraca) belonging to the genus Sarsinebalia are described from shallow waters off Galicia (northwest Spain). The new species differ from S. typhlops , the only known member of the genus, mainly in having ommatidia externally visible and pigmented eyes, as well as a second maxilla bearing an exopod that is longer than the first article of the endopod. The validity of Sarsinebalia is discussed in the light of the new species described. [ABSTRACT FROM AUTHOR]

Examines the phylogeny and biogeographic patterns of devonian phyllocarid crustaceans. Indicator of invasive species; Association of the phyllopodous nature of phyllocarid thoracic appendages with branchiopods and cephalocarids; Classification of archaeostraca.

Studies the life-history patterns of two Californian Nebalia species, namely the Crustacea and Leptostraca. Propensity of either species to move into and potentially exploit the habitat of the other; Relationship between female size and fecundity of the two species; Examination of behavioral differences.