Description of a new species of deep-water crab of the genus Homolodromia A. Milne-Edwards, 1880 from the northern Indian Ocean (Crustacea: Decapoda: Brachyura: Homolodromiidae)

ABSTRACT

Homolodromia rajeevani, a new species of deep-water homolodromiid sponge crab, is described from the northern Indian Ocean (Arabian Sea, depth 957 m, and Bay of Bengal, 645 m), and is the first record of the genus from the area. This species resembles the western Indian Ocean species, namely, Homolodromia bouvieri Doflein, 1904, in having 2 terminal spines on the propodi of the last two pereopods, but can be easily distinguished from the latter species by the inflated carapace, simple long setae on carapace and appendages, slender pseudo-rostral spines separated by a U-shaped base, and a slender arched dactylus of cheliped with maximum elevation at proximal part which bears broadly circular depressions with sparse setae. The most diagnostic character is the higher number of spines on the occlusal surfaces of propodal thumbs and dactyli of the pseudochela of the last two pereopods as compared to H. bouvieri. A key for the identification of the species under the genus Homolodromia is also provided.

http://zoobank.org/urn:lsid:zoobank.org:pub:48894F49-5124-4723-9FF2-3D30FB536DA5     

Dolichopteryx rostrata, a new species of spookfish (Argentinoidea: Opisthoproctidae) from the eastern North Atlantic Ocean

A new species, Dolichopteryx rostrata, is described on the basis of a single specimen (66.2 mm in standard length) collected west of the Hebrides Islands, eastern North Atlantic Ocean. The new species is characterized by an elongate snout and head, small pouchlike eyes, an adipose fin, short dorsal fin base, anal fin base originating under dorsal fin base, a clear longitudinal suborbital brownish band extending forward from behind posterior margin of orbit to snout tip, and 41 (=26 + 15) vertebrae. Total fecundity is low; the ovarian eggs number only 473, despite the ovary having developed ova. Ovarian eggs could be clearly subdivided into an “undeveloped group” (0.1–0.7 mm diameter classes, n = 405) and a “developed group” (0.9–1.3 mm classes, n = 68), based on their frequency distribution. Supplementary material to this paper is available in electronic format at http://dx.doi.org/10.1007/s10228-005-0306-2     

A new species of Stenochironomus Kieffer, 1919 from the Atlantic Rainforest in southern Brazil (Diptera: Chironomidae)

Stenochironomus falcifer sp. n. is described and figured based on the characters of a male adult. The species was collected in Malaise traps in the Serra Furada State Park (PAESF), in Santa Catarina State, southern Brazil. It can be separated from all other species of Stenochironomus Kieffer, 1919 Kieffer, J.J. (1919), ‘Chironomiden der Nördlichen Polarregion’, Entomologische Mitteilungen, 8, 40–48. [Google Scholar] by its unique thorax pigmentation, with two dark patches on the lateral vittae, brownish postnotum and dark stripes on the scutum, and also by the combination of a narrow, parallel-sided anal point, inferior volsella with a stout apical seta, rounded posterior margin of the tergite IX and green metallic eyes.

http://zoobank.org/urn:lsid:zoobank.org:act:3646E02D-7E3F-487A-BED1-A7937AFF8040     

Four new species of Desmosomatidae Sars, 1897 (Crustacea: Isopoda) from the deep sea of the Angola Basin

From a total of 104 species and 1741 individuals of Isopoda, the material from DIVA-1 (DIVersity of the Atlantic benthos) contained 364 specimens belonging to Desmosomatidae Sars, 1897. They are represented by 10 genera and 27 species. Most species (93%) are new to science. Four species are described in this study (Eugerdella theodori sp. nov., Desmosoma renatae sp. nov., Torwolia tinbiene sp. nov. and Momedossa longipedis sp. nov.). A discussion of the genera Desmosoma Sars, 1864, Momedossa Hessler, 1970 and Torwolia Hessler, 1970 is presented.     

An Oplegnathid beak (Osteichthyes: Perciformes) from the Early Miocene of Patagonia. Extirpation of several vertebrates from the southern Atlantic Ocean

The first record of the knifejaw family Oplegnathidae in the Atlantic Ocean and in South America is reported. It comes from the lowermost beds of the Early Miocene Gaiman Formation at the lower Río Chubut valley, central-eastern Patagonia. The family Oplegnathidae does not occur in the Atlantic today, but it was widespread in comparison to other knifejaw fishes, such as scarids and odacids. Several aquatic vertebrates were extirpated from the southern Atlantic Ocean in the Late Neogene. This record establishes a minimal age (Early Miocene) for the extirpation of the family Oplegnathidae in the Atlantic Ocean.     

Dubinectes infirmus, a new species of deep-water Munnopsidae (Crustacea, Isopoda, Asellota) from the Argentine Basin, South Atlantic Ocean

Dubinectes infirmussp. n., Munnopsidae, is described from the Argentine Basin, southwest Atlantic, at depths between 4586-4607 m. The new species is distinguished by a narrow rim of the pleotelson posterior margin which is not raising over its dorsal surface; article 3 of the antennula is subequal in length to article 2; distomedial lobes of male pleopod 1 are of same size as distolateral lobes; stylet of male pleopod 2 is subequal in length to protopod; uropod exopod is more than a half of endopod length. Some generic characters which are weakly pronounced in the new species or have different state are defined more precisely in the revised diagnosis of Dubinectes. The modified diagnosis of the genus, a key to the species of Dubinectes as well as the distribution of the genus are presented.     

A new genus and species of deep-sea glass sponge (Porifera, Hexactinellida, Aulocalycidae) from the Indian Ocean

New hexactinellid sponges were collected from 2589 m depth on the Carlsberg Ridge in the Indian Ocean during deep-sea dredging. All fragments belong to a new genus and species, Indiellagen. n.ridgenensissp. n., a representative of the family Aulocalycidae described here. The peculiar features of this sponge, not described earlier for other Aulocalycidae, are: longitudinal strands present in several layers and epirhyses channelization.     

Squalus bassi sp. nov., a new long‐snouted spurdog (Chondrichthyes: Squaliformes: Squalidae) from the Agulhas Bank

The long‐snouted African spurdog Squalus bassi sp. nov. is described based on material collected from the outer shelf and upper continental slope off South Africa and Mozambique. Squalus bassi shares with S. mitsukurii, S. montalbani, S. chloroculus, S. grahami, S. griffini, S. edmundsi, S. quasimodo and S. lobularis a large snout with prenarial length greater than distance between nostrils and upper labial furrows, dermal denticles tricuspidate and rhomboid and elevated number of vertebrae. Squalus bassi can be distinguished from all its congeners by a combination of body and fin colouration, external morphometrics, vertebral counts and shape of dermal denticles. Similar long‐snouted congeners from the Indo‐Pacific region, including S. montalbani, S. edmundsi and S. lalannei are compared in detail with the new species. This new species has been misidentified as the Japanese S. mitsukurii and the Mediterranean S. blainvillei due to the lack of comparative morphological analyses. The validity of the nominal species S. mitsukurii in the south‐eastern Atlantic Ocean and western Indian Ocean is also clarified herein, indicating it has a more restricted geographical distribution in the North Pacific Ocean.     

Diversity of isopods (Crustacea): new data from the Arctic and Atlantic Oceans

New data on the diversity pattern of isopods (Crustacea) from the northern most part of the North Atlantic and the Arctic Oceans is presented. The pattern of diversity with depth is similar at depths <1000m, but differs considerably below about 1000m. In the Arctic the diversity of isopods (expressed both as numbers of species per sled and expected number of species) increased with increased depth to a maximum at depths of about 320 to 1100m, but then declined towards deeper waters. There was a significant increase in numbers per sled and in the expected number of species with increased depth in the northernmost part of the North Atlantic Ocean. Additionally, changes occurred in the relative composition of the shallow and deep water fauna, with asellote isopods being relatively larger part of the isopod fauna in the Arctic than in the northern most part of the North Atlantic. This indicates major faunistic changes occurring at the Greenland-Iceland-Faeroe Ridge, possibly caused by rapid changes in the temperature. Furthermore, that the low diversity of the Arctic deep-sea is a regional phenomenon, and not a part of a large scale latitudinal pattern in the North Atlantic.     

Prionospio atrovitta (Annelida: Spionidae), a new species from Andaman and Nicobar archipelago,northern Indian Ocean

ABSTRACT

A new species of polychaete, Prionospio atrovitta, is described from the sandy sediments of the Andaman and Nicobar insular margin. The major feature distinguishing P. atrovitta from other species of the genus Prionospio is the presence of well-marked black pigmented band near the anterior dorsal margin of the prostomium and pigmentation on the caruncle in the adults.     

New species and new records of Callionymus from the Pacific Ocean (Teleostei: Callionymidae)

Recently obtained material of Callionymus from the Pacific Ocean includes: Callionymus marquesensis sp. n. (Marquesas Islands), characterized within the C. variegatus-group of the subgenus Calliurichthys by its preopercular spine formula of with an upcurved main tip and a bony keel between the points on the dorsal margin, and a spotted dorsal fin without filaments which is higher than the 1st D₂ ray in both sexes; C. pleurostictus Fricke, 1982, record from New Britain and Solomon Islands, with a discussion of competition with C. delicatulus; C.simplicicornis Valenciennes, 1837, record from Society Islands and Marquesas Islands, with a discussion of competition with C. marquesensis; C. obscurus sp. n. (Ambon, Indonesia) which is characterized within the subgenus Spini-capitichthys by its preopercular spine formula with an upcurved main tip and very small ventral serrae, its weakly armed head, and its 7 anal fin rays.     

Revision of the bathyal cusk-eels of the genus Bassogigas (Ophidiidae) with description of a new species from off Guam, west Pacific Ocean

The bathyal genus Bassogigas (Teleostei: Ophidiidae) is revised based on 25 specimens, 18 from the west Atlantic Ocean and seven from the Indo-west Pacific Ocean. One specimen, from off Guam, west Pacific Ocean, represents a new species, Walker's cusk eel Bassogigas walkeri. The other 24 specimens all belong to the type species, Gills cusk eel Bassogigas gillii. A comparison between the Atlantic and the Indo-west Pacific Ocean specimens of B. gillii showed no differences in meristic and morphometric characters, but in two of the Indo-west Pacific Ocean specimens the sagittal otolith varied somewhat from the remaining specimens. The two Bassogigas species differ in the length of the lateral line, the number of scales in the midline of the body, the form of the median basibranchial tooth patches and in the thickness of the otolith.     

A tropical Atlantic species of Melibe Rang, 1829 (Mollusca,Nudibranchia, Tethyiidae)

A new species of Melibe is described based on two specimens collected in Florida. This new species is well differentiated morphologically and genetically from other species of Melibe studied to date. The four residue deletions in the cytochrome c oxidase subunit 1 protein found in all previously sequenced tropical species of Melibe sequenced (and Melibe rosea) are also present in this new species. These deletions do not appear to affect important structural components of this protein but might have fitness implications. This paper provides the first confirmed record of Melibe in the tropical western Atlantic Ocean.     

Chimaera opalescens n. sp., a new chimaeroid (Chondrichthyes: Holocephali) from the north-eastern Atlantic Ocean

A new species of chimaeroid, Chimaera opalescens n. sp., was described from 31 type specimens caught in the north-eastern Atlantic Ocean at 950-1400 m depth. This species differed from all its congeners by the combination of the following characters: body uniformly pale brown to bronze, iridescent on fresh specimens; unpaired fins brown to purple, uniformly coloured or with pale or whitish edges; iris black; claspers tripartite and divided for a third of their length, not extending beyond the pelvic fins in adults; dorsal spine equal to or shorter than first dorsal fin; ventral caudal lobe equal to or deeper than dorsal caudal lobe. Comparison of DNA sequences of the CO1 gene with those of related species supported C. opalescens n. sp. as a distinct species. Specimens of C. opalescens n. sp. were previously misidentified as Chimaera monstrosa, a species sharing a similar geographical distribution. Chimaera opalescens n. sp. lives in deeper water and is a larger-bodied species than C. monstrosa. The two species were newly exploited by deep-sea fisheries and confused under a single landing name.     

A new lacazelline species (Brachiopoda,Recent) from the Maldive Islands,Indian Ocean

A new lacazelline brachiopod species is described from reef caves in the outer reef slope zone off Addu and South Male atolls in the Maldive Islands, Indian Ocean. Based on anatomical features of the soft parts, shell morphology and shell microstructure the new taxon is assigned to the genus Ospreyella Lüter and Wörheide 2003 in the subfamily Lacazellinae of the family Thecideidae. This new species, here named O. maldiviana and representing the first occurrence of the genus in the Indian Ocean, is compared with the type species O. depressa Luter from Osprey Reef, Coral Sea, Australia. Comparisons are made between Ospreyella (now two species) and the other extant lacazelline genera Lacazella Munier‐Chalmas (three species) and Pajaudina Logan (one species).     

A preliminary study of two species of flatfish (family: Bothidae) from the south-west Atlantic

Two species of the family Bothidae (lefteye flounders), Mancopsetta maculata metadata and M. milfordi occur in the south-west Atlantic but are caught rarely by commercial bottom trawlers. Little is therefore known about their general biology from this area. A total of 251 M. maculata and 276 M. milfordi were sampled during deep-water exploratory fishing conducted in November 1994 within the Falkland Islands Interim and Outer Conservation Zones, at depths of 400-1000 m, using standard commercial bottom trawling gear. The two species were found to have similar geographical distributions between 48.30'-53.30'S and 55°-62° W and were often obtained at the same stations in depths of 400-900 m on the continental slope. Mancopsetta maculata maculata showed a uni-modal cohort structure with a modal length at the 29-cm total length size-class. Males of M. m. maculata outnumbered females in a ratio of 3.5 : 1. Mancopsetta milfordi showed a tri-modal length distribution, the main mode at the 37-cm total length size-class, with females outnumbering males in a ratio of 1.1 : 1. Length-weight relationships and length-at-age information are presented for the two species. Diet was determined from the analysis of stomach contents and, although the major prey type for both species consisted of crustaceans, the morid fish Austrophycis marginata also formed an important part of the diet of M. milfordi. Key words: Mancopsetta maculata maculata; Mancopsetta milfordi; distribution; south-west Atlantic; size; diet.     

A new species, Parupeneus procerigena, from the Saya de Malha Bank in the western Indian Ocean (Perciformes: Mullidae)

A new mullid fish, Parupeneus procerigena, is described on the basis of 13 specimens (118.9–198.4 mm SL) from depths of 92–148 m off the Saya de Malha Bank in the western Indian Ocean. This species resembles P. chrysopleuron and P. heptacanthus in color pattern without black stripes or spots, but it differs from them in having more gill rakers, two scales in lachrymal region, deeper body, deeper cheek, and longer distance between nostrils. Received: April 4, 2000 / Revised: July 27, 2000 / Accepted: August 27, 2000     

Biogeographical distribution of Hartaetosiga strains (Choanoflagellatea,Craspedida, Salpingoecidae) including morphological and transcriptomic data from a transect across the Atlantic Ocean

The genus Hartaetosiga Carr, Richter and Nitsche, 2017 comprised up to now only three species, H. gracilis (Kent) Carr, Richter, Nitsche, 2017, H. balthica (Wylezich and Karpov) Carr, Richter and Nitsche, 2017 and H. minima (Wylezich and Karpov) Carr, Richter and Nitsche, 2017. Based on distinct molecular data these species were relocated from the strictly freshwater genus Codosiga (Ehrenberg) Bütschli, 1878 to a new genus comprising brackish and marine species. During the cruise MSM82/2 across the Atlantic Ocean in 2019, surface water samples were taken from 15 stations along a transect ranging from 35°S to 23°N. We were able to isolate and cultivate 14 strains of the genus Hartaetosiga. Morphometric data showed no distinct morphological traits allowing for a species delineation, indicating a cryptic species complex within the genus. Based on cultivation, morphological data, and molecular analyses, we recorded H. gracilis for the first time from off-shelf waters of the Atlantic Ocean and could describe a new species, H. australis n. sp. This new species was recorded from sampling stations in the Southern Hemisphere only, which may indicate a potential biogeographic restriction likely caused by the Equatorial Counter Current (ECC), dividing the northern and southern surface waters.     

A taxonomic study of Whitehead's torrent frog,Meristogenys whiteheadi,with descriptions of two new species (Amphibia: Ranidae)

The genus Meristogenys (Anura: Ranidae), endemic to Borneo, presents serious taxonomic problems despite being one of the commonest frogs in the mountainous regions of this island. We investigated molecular and morphological variations in Meristogenys whiteheadi (Boulenger, 1887) using larval and adult specimens from Sabah and Sarawak (Malaysia). We found three allopatric lineages in this species. We regard each of these as a distinct species because they are separated by a large genetic distance, and do not form any monophyletic group. Their morphological characters indicate that the distributional range of M. whiteheadi s.s. is divided into two disjunct areas: Mt Kinabalu (northern Sabah) and northern Sarawak. The two other lineages occupy ranges between those of M. whiteheadi, and represent undescribed cryptic species. One of these, Meristogenys stigmachilus sp. nov. , collected from the northern part of the Crocker Range, is distinguished from M. whiteheadi by black spots on the upper lip and dark dots scattered on the back. A second undescribed species, Meristogenys stenocephalus sp. nov. , was collected mainly from the southern part of the Crocker Range, and is characterized by the large body size of males and a relatively narrow head. Meristogenys stenocephalus sp. nov. also differs from M. stigmachilus sp. nov. and M. whiteheadi in larval morphology, but larvae of the latter two cannot be differentiated morphologically. We discuss relative tibia length, a diagnostic specific characteristic in the genus Meristogenys, and the relationships between body size and sexual size dimorphism in this genus. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 157–183.