21 results on '"*ECHINODERMATA classification"'
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2. Catalogue of living crinoids (Echinodermata: Crinoidea) from Brazil.
- Author
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Gondim AI, DE Moura RB, and Christoffersen ML
- Subjects
- Animals, Atlantic Ocean, Brazil, Echinodermata classification
- Abstract
Knowledge of living crinoids from Brazil is chiefly restricted to the contributions of Dr Luis Roberto Tommasi between the decades of 1950 and 1970. Herein we present an updated catalogue of the crinoids occurring along the Brazilian coast, including data on synonyms, type localities, type material, geographical distribution, bathymetric ranges, and occurrences of species along the coast. The data is based on an extensive revision of the literature and on a survey of several databases. A total of 20 species were catalogued, of which two are endemic (Phrixometra longipinna var. brasiliensis and Thaumatometra minutissima). According to information from the literature, P. longipinna var. brasiliensis represents an undescribed taxon. Although Brazil supports the greatest number of crinoid species in the Southwestern Atlantic, its crinoid fauna remains understudied and likely underestimated. Research on crinoids remains a subject of great potential, not only for taxonomy but also for other areas of knowledge.
- Published
- 2021
- Full Text
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3. Deep-sea Ophiuroidea (Echinodermata) from the Danish Galathea II Expedition, 1950-52, with taxonomic revisions.
- Author
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Stöhr S and O'Hara TD
- Subjects
- Animal Distribution, Animals, Classification, Denmark, Expeditions, Oceans and Seas, Species Specificity, Echinodermata anatomy & histology, Echinodermata classification, Echinodermata genetics, Phylogeny
- Abstract
The brittle star samples collected by the Danish cruise 'Galathea II' (1950-52) had not been studied completely. We examined the remaining deep-sea samples (400 m) and present the species inventory, discussing taxonomic issues in relation to recent phylogenetic data. About 235 samples were examined, over 9,300 individuals, from 67 species and 74 sampling localities, at depths of 425-5340 m. The species complex Amphiophiura bullata (Thomson, 1877) is morphologically not well separated, but molecular data suggest at least two clades. We propose to apply A. bullata for Atlantic and Australian populations and A. convexa (Lyman, 1878) for the North Pacific clade. We consider A. bullata pacifica Litvinova, 1971 conspecific with A. convexa. Ophiuroglypha irrorata (Lyman, 1878) and its subspecies are a polyphyletic group with unclear morphological boundaries. We propose to transfer Ophiura ossiculata (Koehler, 1908), Ophiura plana (Lütken Mortensen, 1899) and Ophiura scomba Paterson, 1985 to Ophiuroglypha. Silax Fell, 1962, until now synonymised with Amphioplus Verrill, 1899, is proposed as a valid genus with the species S. verrilli (Lyman, 1879), S. consors (Koehler, 1908), S. daleus (Lyman, 1879), S. patulus (Lyman, 1879) and S. magnificus (Koehler, 1907). Triplodia Turner Hallen, 2011 (a replacement name for Triodia A. M. Clark, 1970, due to homonymy) is synonymised with Silax, and possible specimens of its type species Triodia abdita A. M. Clark, 1970 are analysed. The species limits of Ophiacantha cosmica Lyman, 1879 and Ophiacantha pacifica Lütken Mortensen, 1899 could not be confirmed morphologically, but published molecular data suggest two clades. We propose to apply O. pacifica to the Northern/Central Pacific population and O. cosmica to the Southern Pacific/Antarctic population.
- Published
- 2021
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4. A diverse crinoid fauna (Echinodermata, Crinoidea) from the Lower Eocene of the Gulf of Languedoc (Corbières, Aude, southern France).
- Author
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Roux M, Martinez A, and Vizcaïno D
- Subjects
- Animals, France, Oceans and Seas, Species Specificity, Echinodermata anatomy & histology, Echinodermata classification, Fossils
- Abstract
Detailed studies of the middle Ilerdian (lower Ypresian) blue marls of the Gulf of Languedoc (Corbières, Aude, France), belonging to the north Pyrenean foreland basin, have revealed a more abundant and diverse crinoid fauna than previously documented from the Lower Eocene. Here we describe five species of stalked crinoids in the family Rhizocrinidae (Cherbonniericrinus requiensis n. sp., ?Democrinus elongatus, Globulocrinus amphoraformis n. gen., n. sp., Pseudoconocrinus doncieuxi and P. lavadensis n. sp.), one barnacle-like species in the stalkless family Holopodidae (Holopus plaziati n. sp.) and a single feather star in the family Conometridae (Amphorometra atacica). Several sites have yielded brachials and rhizoids in addition to abundant aboral cups and columnals indicating in situ fossilisation of the dissociated skeletal elements. P. lavadensis n. sp. and ?D. elongatus have been collected only from outcrops located in the upper part of the middle blue marls, while P. doncieuxi predominates, with a wide range of morphological variation, in the lower blue marls. The fossil assemblage at the locality of Réqui near Montlaur differs from the others in the smaller size of most individuals and the presence of H. plaziati n. sp., C. requiensis n. sp., G. amphoraformis n. gen., n. sp., and P. doncieuxi suboblongus n. subsp. This particular association with high juvenile mortality corresponds to an unstable environment with mixed substrates (muddy and rocky). The crinoid fauna of the Corbières appears to be the most diverse of Early Eocene age known to date. With the fauna of the London Clay, a boreal formation of the same age, it shares the presence of the genera Democrinus and Amphorometra in an open-sea environment. A comparison with extant faunas allows the depth of deposition at the Ypresian sites in the Gulf of Languedoc to be estimated between from 100 and 140 meters.
- Published
- 2021
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5. Taxonomy of the sea stars (Echinodermata: Asteroidea) from Bahia State, including ontogenetic variation and an illustrated key to the Brazilian species.
- Author
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Cunha R, Martins L, Menegola C, and Souto C
- Subjects
- Animals, Biology, Brazil, Ecosystem, Starfish, Echinodermata classification
- Abstract
Describing ontogenetic morphological change is an important part of integrative taxonomy; still, most taxonomic studies are based only on adult characters. Here, we provide illustrations and a morphological description of the sea stars from Bahia, including ontogenetic and intraspecific variation, and identify taxonomic issues. A total of 293 specimens from different localities along the Bahia State coastline and comparative material from other localities were examined. Eighteen species (11 genera, eight families) of Asteroidea were identified; Astropectinidae was the most representative family. All species identified also occur in subtropical Brazilian waters and most species are from shallow water habitats with soft bottoms. Most observed ontogenetic variation was quantitative in nature, such as the increase in the number of spines in the furrow and of spinelets in the paxillae with specimen growth. Genera that require further taxonomic studies are Astropecten and Othilia, whose specimens are commonly misidentified in local studies. One third of the species from Bahia are currently classified as "Vulnerable" in the Brazilian Red List, but baseline data on the population biology of these species are scarce. An illustrated identification key to the 65 Brazilian sea star species is also provided. This taxonomic study will facilitate the identification of specimens occurring along the Brazilian coast and help scientists and policy makers to establish the conservation status of the Brazilian species.
- Published
- 2021
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6. Porphyrocrinus daniellalevyae n. sp. (Echinodermata: Crinoidea), a sea lily from the tropical western Atlantic with a unique crown pattern.
- Author
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Messing CG
- Subjects
- Animals, Atlantic Ocean, Microscopy, Electron, Scanning, Species Specificity, Echinodermata anatomy & histology, Echinodermata classification
- Abstract
Porphyrocrinus daniellalevyae, new species, is described from irregular, hard-substrate, deep island slope habitats in the tropical western Atlantic Ocean (northwestern Bahamas and, probably, Honduras). It represents the first record of the genus from the western Atlantic, and is the first crinoid, living or fossil, known to gradually increase its number of rays with increasing size and, ostensibly, growth. The four known specimens have 8, 12, 14 and 15 radial ossicles, which give rise to undivided arms. The method of augmentation is unknown, although the possibility of autotomy of one and regrowth of two in its place is discussed. Augmentation of radial number may also account for the absence of an aboral nerve ring associated with the radial ring, unlike the arrangement in almost all living crinoids in which the nervous system has been examined. Ligamentary articulations (trifascial synarthries) exhibit fulcral ridge-and groove architecture between arm ossicle pairs that remains to be described for other members of the genus. The species also exhibits a filamentous arm tip lacking pinnules that has only been described for one other species of Porphyrocrinus.
- Published
- 2016
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7. Shallow-water reef ophiuroids (Echinodermata: Ophiuroidea) of Réunion (Mascarene Islands), with biogeographic considerations.
- Author
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Boissin E, Hoareau TB, Paulay G, and Bruggemann JH
- Subjects
- Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Biodiversity, Body Size, Echinodermata anatomy & histology, Echinodermata growth & development, Ecosystem, Geography, Islands, Organ Size, Echinodermata classification
- Abstract
Despite their importance in marine biodiversity, invertebrates are far less studied than vertebrates. Given the current global biodiversity crisis and insufficient taxonomic resources, sustained efforts need to be undertaken to assess species diversity, especially in the highly threatened 'biodiversity hotspots'. Réunion is a young volcanic island lying in the Mascarene Islands (south-western Indian Ocean, SWIO), a marine biodiversity hotspot. A substantial sampling effort was conducted around Réunion Island to document shallow water reef-associated ophiuroid (brittle-stars) diversity, a class recognised as the most diverse among echinoderms. A total of 33 species were documented, increasing the known species richness of the island by 56%. Findings include 15 new records for Réunion, 11 for the Mascarene Islands and 8 for the Indian Ocean. The most diverse family was Ophiocomidae, a family of large, abundant and conspicuous tropical species. Even in this well studied family, a new species was revealed by this survey. Morphological variants together with DNA sequence variations within several species revealed cryptic species. We compared our results with the known fauna of other Mascarene Islands and discuss biogeographic implications for the region.
- Published
- 2016
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8. Taxonomic status of the genera Amphipholizona H.L. Clark, 1915 <br />(Ophiuroidea, Ophiolepididae) and Amphigyptis Nielsen, 1932 (Hemieuryalidae): systematic placement and synonymy.
- Author
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Gondim AI, Christoffersen ML, Dias TL, and Solís FA
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Body Size, Echinodermata anatomy & histology, Echinodermata genetics, Echinodermata growth & development, Female, Male, Organ Size, Phylogeny, Echinodermata classification
- Abstract
We synonymize Amphipholizona (Ophiolepididae) and Amphigyptis (Hemieuryalidae), suggest their transfer to family Amphiuridae, and propose a new species combination (Amphipholizona perplexa new comb.). We further provide a new diagnosis for the genus Amphipholizona, a dichotomic identification key for the two species now belonging to this genus and re-describe and illustrate for the first time some of the internal characters, such as the genital plates, vertebrae, and inner side of the lateral arm plate.
- Published
- 2016
- Full Text
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9. An illustrated catalogue of type specimens of the bathyal brittlestar genera Ophiomusium Lyman and Ophiosphalma H. L. Clark (Echinodermata: Ophiuroidea).
- Author
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Baker AN
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Body Size, Echinodermata growth & development, Ecosystem, Organ Size, Echinodermata anatomy & histology, Echinodermata classification
- Abstract
Type specimens of 61 species of the bathyal ophiuriod genera Ophiomusium Lyman and Ophiosphalma H.L. Clark are illustrated and their main features outlined, to form a partial catalogue for current and future workers. Thirty-nine species of Ophiomusium and 22 of Ophiosphalma are recognised, based largely on the number of exposed tentacle pores on the basal ventral arm plates. Most of the Ophiosphalma listed here are new combinations from their original genus, Ophiomusium. Ophiomusium sculptum Verrill is a junior subjective synonym of O. acuferum Lyman, and Ophiosphalma fimbriatum (Koehler) is a junior subjective synonym of O. glabrum (Lütken & Mortensen). The subspecies Ophiomusium fimbriatum atlanticum Hertz and Ophiomusium facunda muta Hertz are elevated to full species. Because of their bathyal habitat (<4000 m), representatives of these genera are relatively rare in collections, and it will require fresh material of a range of sizes, for morphological comparison and for DNA analysis, to reliably confirm their taxonomic validity and clarify their relationships.
- Published
- 2016
- Full Text
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10. Sometimes two arms are enough--an unusual life-stage in brittle stars (Echinodermata: Ophiuroidea).
- Author
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Stöhr S and Alme Ø
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Body Size, Echinodermata anatomy & histology, Ecosystem, Organ Size, Echinodermata classification, Echinodermata growth & development
- Abstract
Off West Africa (Angola-Morocco), benthos samples were collected in the years 2005-2012. These contained 124 specimens of brittle stars with two long arms and three extremely short or absent arms and an elongated, narrow disc. These unusual brittle stars, as well as 33 specimens with five fully developed arms, were identified as Amphiura ungulata. The specimens with unequal arms were juvenile stages, whereas adults had five equal arms. The large number of specimens with unequal arms suggests that this condition is not the result of damage and regeneration, but a normal growth pattern in this species. This study documents the morphology by SEM, amends the species description, and discusses possible explanations for the evolution of this condition. Although brittle star species with unequal arm growth have been reported, this is an extreme case that was unknown before this study.
- Published
- 2015
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11. Crinoids of the stalked family Hyocrinidae (Echinodermata) collected by the USNS Eltanin in the Southern Ocean.
- Author
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Roux M
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Body Size, Echinodermata anatomy & histology, Echinodermata growth & development, Female, Male, Museums, Oceans and Seas, Organ Size, Echinodermata classification
- Abstract
Rare species only known from one or a few specimens, mainly collected from abyssal and hadal zones in the Southern Ocean are represented in a collection of stalked crinoids attributed to the family Hyocrinidae (Crinoidea, Echinodermata). The species studied here include Belyaevicrinus latipinnulus Mironov & Sorokina, 1998, Feracrinus heinzelleri Bohn, 2012, Ptilocrinus brucei Vaney, 1908 and Thalassocrinus clausus Mironov & Sorokina, 1998. This collection, mainly collected during the 1960s USNS Eltanin cruises, is housed at the Smithsonian Institution National Museum of Natural History in Washington DC. A detailed study of this material using SEM observations of ossicle articular facets and pinnule architecture allows the emendation of species diagnoses, and a better description of intraspecific variation and of changes in characters through ontogeny. Geographical and depth range extension of species are reported. A gonad with submature ovocytes of 100-150 µm was exceptionally preserved at the base of a genital pinnule of P. brucei. This species likely has a lecithotrophic larval development.
- Published
- 2015
- Full Text
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12. A new genus and new species of family Antedonidae (Echinodermata: Crinoidea) from southern Japan.
- Author
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Obuchi M and Omori A
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Body Size, Echinodermata anatomy & histology, Echinodermata growth & development, Ecosystem, Japan, Organ Size, Echinodermata classification
- Abstract
A new genus and new species of antedonid comatulid is described from southern Japan. Belonometra n. gen. has a unique appearance with ten long arms, numerous cirri, and remarkably long and crowded pinnules. The new genus shares some characters with subfamily Heliometrinae. However, the comparative length of pinnules, which is a diagnostic character to determine subfamily Antedonidae, is different. The subfamily into which the new genus should be placed is unclear.
- Published
- 2015
- Full Text
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13. Revision of some ophiuroid records (Echinodermata: Ophiuroidea) from Argentina.
- Author
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Brogger MI and O'Hara TD
- Subjects
- Animal Distribution, Animals, Argentina, Echinodermata classification
- Abstract
The taxonomy of some ophiuroids reported from off Argentina, western Antarctica and the SW Atlantic Ocean is reviewed. The species Amphilepis sanmatiensis, known only from the small holotype, is a synonym of Amphioplus lucyae. This synonymy removes the only reported endemic ophiuroid from Argentina. The species name "Ophiacantha ingrata Koehler, 1923" used for specimens from South Georgia is invalid; the specimens are likely to belong to one of two cryptic species within the O. vivipara complex. Specimens of Amphiura joubini reported from Argentina are re-identified as Amphiura princeps, and specimens of Ophiactis amator from the Antarctic Peninsula are re-identified as Ophiactis asperula.
- Published
- 2015
- Full Text
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14. Redescription of Hemieuryale pustulata von Martens, 1867 (Echinodermata, Ophiuroidea) based on Brazilian specimens, with notes on systematics and habitat association.
- Author
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Gondim AI, Dias TL, Christoffersen ML, and Stöhr S
- Subjects
- Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Body Size, Brazil, Echinodermata anatomy & histology, Echinodermata growth & development, Ecosystem, Organ Size, Echinodermata classification
- Abstract
We redescribe Hemieuryale pustulata on the basis of 325 specimens obtained from the continental shelf off northeastern and southeastern Brazil. This is the first record of the species for Brazil. We illustrate for the first time details of the dental plate, oral plate, and vertebrae. Few morphological variations were observed in our extensive material. All specimens were associated with the gorgonian Nicella guadalupensis, suggesting an obligatory association in the Brazilian littoral. H. pustulata did not reveal a particular pattern of distribution on its host gorgonian, but larger gorgonians tend to support a larger number of ophiuroids. In addition to expanding the knowledge on morphology and ecology, we extend the known bathymetric distribution of the species, which is now known from 18 to 330 m.
- Published
- 2015
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15. A new species of Western Atlantic sea lily in the family Bathycrinidae (Echinodermata: Crinoidea), with a discussion of relationships between crinoids with xenomorphic stalks.
- Author
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Mironov AN and Pawson DL
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Body Size, Echinodermata anatomy & histology, Echinodermata growth & development, Oceans and Seas, Organ Size, Echinodermata classification
- Abstract
A new species in the family Bathycrinidae is described from abyssal depths from the Bahamas. It is referred to the recently established genus Discolocrinus, which formerly comprised a single species D. thieli Mironov, 2008 from the Eastern Pacific. Discolocrinus iselini n. sp. is characterized by large body size, high tegmen with tube-like upper region, extremely elongated IBr1 and IBr2, large knobby processes on primibrachials, and overgrowth of soft tissue on the pinnules, the tissue containing numerous perforated or imperforate ossicles of varying size and form. Differences between Discolocrinus and other bathycrinids may seem to be of taxonomic importance at the family level, but knowledge of the morphology and variability of both species of Discolocrinus is incomplete and, until a richer material becomes available, the genus should remain in family Bathycrinidae. Representatives of five families with xenomorphic stalks were examined to characterize the genera on the basis of number or form of knobby processes. These processes occur in two families with differing external morphology: ten-armed Bathycrinidae and five-armed Bourgueticrinidae. They also occur in the comatulid family Atelecrinidae. This similarity might seem to indicate a close relationship between the three families. However, morphological analysis supports the separation of the families Caledonicrinidae and Septocrinidae from Bathycrinidae despite the fact that they share a xenomorphic stalk and IBr2ax. These conclusions are in agreement with results of recent molecular studies.
- Published
- 2014
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16. Revision of the genus Ophioteichus H.L. Clark, 1938 (Ophiuroidea: Ophiolepididae).
- Author
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Pineda-Enriquez T, Solis-Marin FA, and Laguarda-Figueras A
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animals, Echinodermata anatomy & histology, Ecosystem, Oceans and Seas, Echinodermata classification
- Abstract
In this study we re-describe the ophiuroid genus Ophioteichus H.L. Clark, 1938 and diagnose the species using existing and new characters found by examining the type material. The species Ophiolepis utinomii Irimura, 1967, is very similar to the holotype of Ophioteichus multispinum, and is herein transferred to the genus Ophioteichus; this transfer expands the geographic range of the genus. Ophioteichus is currently composed of three species: Ophioteichus parvispinum, Ophioteichus multispinum and Ophioteichus utinomii comb. nov. The genus is now known from the eastern part of Australia, Philippines and the coast of Japan, with a bathymetric range from littoral down to 45.3 m.
- Published
- 2014
- Full Text
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17. Comments on "the phylogeny of post-Palaeozoic Asteroidea (Neoasteroidea, Echinodermata)" by A.S. Gale and perspectives on the systematics of the Asteroidea.
- Author
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Blake DB and Mah CL
- Subjects
- Animals, Echinodermata genetics, Fossils, Publications, Echinodermata classification, Phylogeny
- Abstract
A new, morphologically based classification of extant asteroids with comments on select fossils was published by A.S. Gale. Research approaches used limited sampling, and much literature treatment is not accurate and therefore misleading. We review these concerns, seeking to clarify argumentation on differing interpretations.
- Published
- 2014
- Full Text
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18. Ophiuroids (Echinodermata; Ophiuroidea) of biogenic habitats on the continental shelf of New Zealand.
- Author
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Mills VS and O'Hara TD
- Subjects
- Animal Distribution, Animals, Biodiversity, Echinodermata physiology, Ecosystem, New Zealand, Echinodermata anatomy & histology, Echinodermata classification
- Abstract
The taxonomy of ophiuroids collected in 2009 and 2011, from biogenic habitats across the New Zealand continental shelf, is reviewed. Ophionereis novaezelandiae Mortensen, 1936, and its junior synonym Ophionereis terba Baker & Devaney, 1981 from South-Eastern Australia, is now recognised as a distinct species, and has been removed from synonymy with Ophionereis fasciata Hutton, 1872. Ophiacantha abyssicola var. otagoensis Fell, 1958 is also recognised as a distinct species and has been removed from synonymy with Ophiacantha brachygnatha Clark H L, 1928. Amphiura eugeniae var. latisquama Mortensen, 1924 is raised to species rank and Amphioplus longirima Fell, 1952 treated as a synonym of A. latisquama. Ophiolycus farquhari McKnight, 2003 is transferred to the genus Ophiologimus. The diagnostic characters of several other species are reviewed and colour descriptions and images are included where available. The tropical species Ophiacantha longidens Lyman, 1878, Ophiotreta valenciennesi (Lyman, 1879) and Ophiobyrsa intorta (Koehler, 1922) are reported from New Zealand waters for the first time.
- Published
- 2013
- Full Text
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19. A review of New Zealand and southeast Australian echinothuriinids (Echinodermata: Echinothuriidae) with descriptions of seven new species.
- Author
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Anderson OF
- Subjects
- Animals, Australia, New Zealand, Echinodermata anatomy & histology, Echinodermata classification
- Abstract
Examination of a large collection of echinothurioid echinoids from museum collections in New Zealand and Australia revealed six new species in the genus Araeosoma (A. bidentatum sp. nov., A. migratum sp. nov., A. anatirostrum sp. nov., A. tertii sp. nov., A. leppienae sp. nov., and A. bakeri sp. nov.) and one in the genus Hapalosoma (H. amynina sp. nov.), while the recorded presence of A. coriaceum in northwest New Zealand was found to be incorrect. Several of the species described are rarely collected, their distribution being strongly associated with seamount type habitat in a relatively narrow depth range. The majority of the records of these new species are from the New Zealand region, with a strong centre of diversity revealed among the seamounts of the Bay of Plenty. The new species are clearly distinguished from known forms by characters of their pedicellariae, spines, coronal plate structure, colouring, and tuberculation. A key to the Echinothuriinae of the region is included.
- Published
- 2013
- Full Text
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20. Trachythyoneflaccida, a new sea cucumber species from southern Angola (Echinodermata:Holothuroidea:Dendrochirotida:Cucumariidae) with key to the genus.
- Author
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Thandar AS
- Subjects
- Angola, Animal Distribution, Animals, Atlantic Ocean, Species Specificity, Echinodermata anatomy & histology, Echinodermata classification
- Abstract
A new species of a cucumariid holothuroid, Trachythyone flaccida, is described from shallow water off the southern coast of Angola. This increases to 20 the number of species in the genus Trachythyone. The new species is characterized by a soft, barrel-shaped body, scattered non-retractile tube feet, and body wall ossicles comprising a superficial layer of cup-like baskets and a deeper layer of simple, smooth, multilocular plates; cross-shaped deposits may also occur. The new species appears most closely related to the subantarctic T. bouvatensis (Ludwig & Heding, 1935) and to the Brazilian T. crassipeda Cherbonnier, 1965. A key is provided to all species currently classified in this genus.
- Published
- 2013
- Full Text
- View/download PDF
21. A revision of the genus Atelecrinus PH Carpenter (Echinodermata: Crinoidea).
- Author
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Messing CG
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animals, Echinodermata anatomy & histology, Pacific Ocean, Echinodermata classification
- Abstract
The unusual bathyal comatulid crinoid genus Atelecrinus is widespread in the Atlantic and tropical Pacific Oceans and currently includes three recognized species. A re-assessment based on examination of new and existing specimens requires establishment of two new genera and five new species, and returns three junior synonyms to species-level status. Paratelecrinus is erected to accommodate Atelecrinus wyvilli PH Carpenter, A. conifer AH Clark, A. cubensis PH Carpenter, P. orthotriremis, new species, P. amenouzume new species, P. laticonulus new species and P. telo new species. Adelatelecrinus is erected to accommodate Atelecrinus sulcatus AH Clark and Adelatelecrinus vallatus new species. Atelecrinus retains A. balanoides PH Carpenter and A. helgae AH Clark, which restricts the genus to the Atlantic. In both Paratelecrinus and Adelatelecrinus, the basals articulate with the centrodorsal via ligament bundles anchored in deep ringlike interradial pits that project into the centrodorsal cavity, whereas in Atelecrinus the centrodorsal rim has shallow interradial concavities and attaches to the basals via a tight junction with no obvious ligament bundles. The spoon-shaped aboral fossa in the basals of Paratelecrinus appears to be unique among articulate crinoids and differs from the smooth fossa found in both Atelecrinus and Adelatelecrinus. New material extends the range of the family to the Indian Ocean. A few species are now known from enough specimens to identify some ontogenetic and distributional variations. Proximal ray morphology varies substantially with size in P. cubensis and P. orthotriremis. A. balanoides generally occurs in deeper water in the Lesser Antilles than in the Bahamas and Strait of Florida, while P. orthotriremis occurs in shallower water in the Lesser Antilles and deeper in the Bahamas.
- Published
- 2013
- Full Text
- View/download PDF
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