Sexual dimorphism and mental barbel structure in the South Georgia plunderfish Artedidraco mirus (Perciformes: Notothenioidei: Artedidraconidae)

A recent sample (28 specimens from South Georgia and 1 from Shag Rocks) of the plunderfish Artedidraco mirus collected in June 2004 during the ICEFISH Cruise yielded sufficient data to refute two long-held assumptions about this species: (1) it is endemic to South Georgia; (2) its mental barbel is sexually dimorphic (tapered in females and club-shaped with papillae in males). A. mirus exhibits three types of mental barbel: A: tapered without a terminal expansion; B: with a narrow terminal expansion composed of simple papillae; C: with a wide terminal expansion composed of convoluted or elaborately branched papillae. There is no correlation between barbel type and body size or sex. We also found sexual dimorphism in the relative height of the second dorsal fin (30% higher on average in males) and in the colour of the anal fin (black in males over 60 mm SL). The largest males possess a prominent ruffled urogenital papilla, also black in colour. Barbel histology resembles that of other artedidraconids (Dolloidraco longedorsalis, Pogonophryne scotti) studied in containing large nerve trunks and blood vessels lateral to a pseudocartilaginous core and dermal papillae with an extensive network of nerves and blood vessels. The high degree of intraspecific variation in artedidraconid barbel structure warrants caution in using this structure as a diagnostic taxonomic character.     

<Emphasis Type="Italic">Johnius</Emphasis> (<Emphasis Type="Italic">Johnius</Emphasis>) <Emphasis Type="Italic">majan</Emphasis> sp. nov., a sciaenid fish (Pisces: Sciaenidae) from Oman,Indian Ocean

Johnius (Johnius) majan sp. nov. is described on the basis of 8 specimens (117–158 mm in standard length) from Oman, Indian Ocean. The new species is distinguished from its congeners by the following combination of characters: black axillary spot on upper pectoral fin base; dorsal soft rays 29–32; anal soft rays 8; scales above lateral line 6, below 11; eye diameter 22.9–28.9% HL; interorbital width 32.0–38.0% HL; gill rakers 5–6 + 15–18 = 21–24; no mental barbel; last well developed pleural rib on 7th vertebra; swim bladder appendages 11; vertebrae 10 + 14 = 24.     

Taxonomic studies of the Antarctic icefish genus Cryodraco Dollo, 1900 (Notothenioidei: Channichthyidae)

Based on a meristic and morphometric study of 101 specimens, we recognise 2 valid species in the Antarctic channichthyid genus Cryodraco: Cryodraco antarcticus Dollo, 1900 and C. atkinsoni Regan, 1914. Although the species overlap in most meristic and morphometric characters, we have distinguished several reliable characters for diagnosis and identification. Multidimensional scaling, a nonparametric multivariate technique, clearly separates the two species on the basis of pelvic fin length, head length, number of second dorsal fin rays and origin of the lower lateral line relative to the anal fin rays. We provide a revised identification key to the species of Cryodraco. From a zoogeographical point of view, C. antarcticus has a circum-Antarctic distribution whereas C. atkinsoni is largely confined to the East Antarctic Zoogeographic Province.     

Revision of Iquius nipponicus Jordan 1919 (Teleostei: Cyprinidae) from the Miocene of Iki Island, Nagasaki, Japan and its phylogenetic position

Iquius nipponicus Jordan 1919 was described on the basis of a single specimen from the Miocene of Iki Island, Nagasaki, Japan, and was tentatively assigned to the family Clupeidae. The holotype consists of the anterior portion of the body (lacking the anal and caudal fins and most of the caudal vertebrae), and is re-examined. The species is re-described based on additional specimens from the type locality. This species possesses an extremely stout third dorsal spine-like fin ray with a smooth posterior edge, an expanded anterior portion of the maxilla covering approximately half of the bone, 13 branched anal fin rays, and 22 abdominal and 16 caudal vertebrae. A phylogenetic study using the character matrix from a previous study suggests that the species forms a clade with xenocyprinins, but it differs from xenocyprinins in the form of the maxilla and the dentary and the numbers of branched anal fin rays and vertebrae. The present study concludes that the genus Iquius does not belong to the family Clupeidae. Iquius is a distinct and valid genus that is closely related to cultrins and xenocyprinins of the family Cyprinidae.     

A new pearleye (Teleostei,Aulopiformes) species from the Oligocene of Romania

A new pearleye species of the alepisauroid family Scopelarchidae, Scopelarchoides neamticus sp. nov., is described herein based on two specimens from the Oligocene Lower Dysodilic Shales Formation, cropping out in the Pietricica Mountain, Romanian Eastern Carpathians. The new species described herein exhibits a unique combination of features (including head length about 25% of SL; coracoid remarkably expanded; both preorbital and postorbital lengths larger than orbit diameter; 50 or 51 vertebrae; dorsal fin with nine or ten rays; anal-fin with 28 rays; length of anal fin base about 30% of SL; preanal distance almost 60% of SL; pelvic fin insertion located just under the second dorsal fin ray; pectoral fins only slightly longer than pelvic fins; caudal fin with 19 principal rays plus 14 upper and 13 lower procurrent rays) that justifies its recognition as a new species of the genus Scopelarchoides. Both morphological and meristic features suggest a certain degree of similarity between S. neamticus sp. nov. and the extant species Scopelarchoides signifer. The fossils of the new Oligocene species described herein represent the oldest known skeletal record of Scopelarchidae.     

Channa panaw, a new channid fish from the Irrawaddy and Sittang River basins, Myanmar

Channa panaw sp. nov. (Channidae) is described from 32 specimens collected from the Irrawaddy and Sittang River basins, Myanmar. It is distinguishable from all known congeners by the combination of the following characters: 32–35 dorsal fin rays, 23–24 anal fin rays, 17–20 pectoral fin rays, 39–41 lateral line scales, 39–41 total vertebrae, one large scale on each side of the lower jaw (rarely 2 on one side), pelvic fin length always more than 50% of pectoral fin length, and 7–12 irregular black blotches on the upper half of the body.     

A new genus and species of deepwater codfish (Pisces: Moridae) from New Zealand

Abstract

Momonatira globosus, a new monotypic genus and species of Moridae, is described from five specimens taken in 1153–1184 m from South Canterbury Bight, New Zealand. Spindle shaped otoliths indicate affinities with genera within the Physiculus group. Momonatira is distinctive in having broad fleshy bases to the dorsal and anal fins; a very large globular head; no light organ or barbel; 5–6 rays in the ventral fin; the lower jaw included and in other characters.     

A larva of Coryphaenoides pectoralis (Gadiformes: Macrouridae) collected by deep-sea submersible from off Hokkaido, Japan

A late-stage larva of Coryphaenoides pectoralis was first observed in situ and subsequently collected by the deep-sea submersible “Shinkai 2000” from mesopelagic waters at a depth of 530 m off Hokkaido, Japan. The larva (14.5 mm in head length, 149+ mm in total length) has fan-like pectoral fins, elongate first dorsal fin, pelvic fin and tail, 10 first dorsal rays (including 2 pseudospines), and 7 pelvic fin rays, 6 branchiostegal rays, no light organ, anus just anterior to anal fin origin, 2 retia and gas glands, 14 abdominal vertebrae, and previously reported larval pigmentation. Counts of second dorsal and anal fin rays, and caudal vertebrae, are reported for the first time.     

长江刀鲚不同生态型间的某些形态差异

摘要：为寻找和检验长江刀鲚（Coilia nasus）不同生态型间的形态差异,分析了江苏靖江、上海九段沙、浙江太湖和江西鄱阳湖4个种群906尾样本的脊椎骨数、臀鳍条数和上颌骨长。结果表明,即使是同一种群内的脊椎骨数和臀鳍条数变幅也较大,但均以靖江和九段沙种群的较多,众数分别为81、80和108、109;太湖和鄱阳湖种群...     

Descriptive morphology of pelagic juvenile of <Emphasis Type="Italic">Lepidion inosimae</Emphasis> (Gadiformes: Moridae) collected from off northeastern Japan

A pelagic juvenile (74.0 mm in standard length) of Lepidion inosimae was collected by midwater trawl (0–20 m depth) from the transition waters between the Kuroshio and Oyashio fronts off northeastern Japan. The specimen is characterized by an elongate body, a chin barbel, a minute first ray and non-elongated second ray of first dorsal fin, combination of 55 second dorsal fin rays and 52 anal fin rays, and no ventral luminous organ. This is the first report of early life stages in the genus Lepidion.     

Redescription of Symphurus diabolicus, a poorly-known, deep-sea tonguefish (Pleuronectiformes: Cynoglossidae) from the Galápagos Archipelago

Symphurus diabolicus, previously known only from the holotype collected in 501 m west of Isla San Cristobal (Chatham Island), Galápagos Archipelago, is re-described based on the holotype (112.6 mm SL) and 19 additional specimens (61.1-123.5 mm SL) recently collected from deep waters around the Galápagos Archipelago. Symphurus diabolicus is characterized by: an elongate body; narrow head with pointed snout; 1-3-2 ID pattern; 106-110 dorsal-fin rays; 89-96 anal-fin rays; 12 caudal-fin rays; 57-59 total vertebrae; 5 hypurals; extremely small scales; no pupillary operculum; large, prominent eyes, with migrated eye near dorsal margin of head; relatively short postorbital head length; relatively long snout and predorsal lengths; black peritoneum visible through abdominal wall on both sides of body; uniform olive green to dark brown ocular-side coloration with series of prominent, darker brown, elliptical to rectangular, blotches (not usually forming crossbands) along body at bases of dorsal and anal fins; and uniformly whitish or light yellow blind side. Symphurus diabolicus appears to be endemic to the Galápagos Archipelago, and is relatively common (captured at 16 different localities) at depths of 308 to 757 m (observed as shallow as 245 m) in this region. Examination of this expanded series of specimens confirms the validity of S. diabolicus and provides characters to distinguish it from S. microlepis Garman, a similar species known only from the holotype taken at approximately 530 m off Pacific Panama.     

Reexamination of <Emphasis Type="Italic">Bregmaceros lanceolatus</Emphasis> Shen, 1960 with description of a new species <Emphasis Type="Italic">Bregmaceros pseudolanceolatus</Emphasis> (Gadiformes: Bregmacerotidae)

Based on our reexamination of the 9 specimens including the neotype, Bregmaceros lanceolatus is recharacterized and diagnosed by the following combination of features: caudal fin rounded; scales present on gill cover; dorsal surface of snout unpigmented or with a few chromatophores; isthmus pigmented with punctate chromatophores; two parapophyses on abdominal vertebrae; dorsal rays (D) 65–74; anal rays (A) 67–74; vertebrae (V) 58–61; longitudinal scales (LS) ca. 82–88; principal caudal rays (PC) 16–18; head length (HL)/standard length (SL) 14.0–15.5%; caudal peduncle depth/SL 3.2–4.2%. Based on 27 specimens, B. pseudolanceolatus sp. nov. is described. This species is closely similar to B. lanceolatus, but is diagnosed by the following combination of features: caudal fin rounded; scales present on gill cover; dense concentration of chromatophores on dorsal surface of snout; isthmus colorless; one board-like parapophysis on the last three abdominal vertebrae; D 58–64; A 58–67; V 52–55; LS ca. 68–77; PC 14–16; HL 15.5–18.4% SL; caudal peduncle depth 4.1–5.2% SL. Bregmaceros pseudolanceolatus is known from around the Taiwan Strait, southern East China Sea, South China Sea, Gulf of Thailand, Timor Sea, Arafura Sea, and eastern Bay of Bengal.     

A New Trichomycterus (Siluriformes: Trichomycteridae) from Aguarague National Park of the Bolivian Preandean Region, with Comments on Relationships within of the Genus

Synopsis The Andean and preandean regions are characterized by the presence of several endorheic drainage basins, each of which has evolved a characteristic fish fauna, some of which are poorly known or hitherto inaccessible. We describe here a new species of Trichomycterus from Aguarague National Park, Bolivia. Trichomycterus aguarague is considered to belong to a species assemblage comprised of T. alterus, T. boylei, T. ramosus, and T. belensis, a group diagnosed by three putative apomorphic conditions: (1) base of the maxillary barbel wide and engrossed like a skin flap or fold, (2) premaxillary bone smaller than maxilla, and (3) odontodes embedded in thick integument that covers interopercle. Alternatively, T. aguarague and T. alterus share an unusual number of five or fewer abdominal vertebrae, which is a synapomorphy for the group composed of Scleronema, Ituglanis, and the Stegophilinae+Tridentinae+Vandelliinae+Glanapteryginae+Sarcoglanidinae clade. The new species differs from all congeners in having the following combination of characters: caudal peduncle depth 13.5 – 16.0% SL, 15 or 16 pairs of ribs, 15 dorsal procurrent rays, 12 ventral procurrent rays, 8 pectoral fin rays; 9 anal fin rays; barbels and skin of trunk with numerous, minute thread-like papillae.     

Schindleria elongata,a new species of paedomorphic gobioid from the Red Sea (Teleostei: Schindleriidae)

A new species of paedomorphic gobioid, Schindleria elongata, from the Red Sea, is described on the basis of five specimens. The new species is characterized by its lack of body pigmentation; the body depth at pectoral‐fin origin 4–5% of standard length (L_S) and at anal‐fin origin 5–7% L_S; the predorsal length 66–70% L_S; pre‐anal length 66–71% L_S; dorsal‐fin rays 13 or 14; anal‐fin rays 10 or 11; first dorsal‐fin ray at myomere 20 or 21; first anal‐fin ray below second to fourth dorsal‐fin rays; myomeres 19 or 20 + 13 or 14 = 33 or 34 total; premaxillae and dentaries with small teeth; gas bladder located posteriorly at 56–60% L_S; males with a rod‐like, flexible urogenital papilla lacking lobes, projections or accessory papillae, with distal half tapering to a broad, angular point and usually posteriorly directed. A key to the species of Schindleriidae is presented.     

A new sand whiting, Sillago (Sillago) caudicula, from Oman, the Indian Ocean (Perciformes: Sillaginidae)

A new species of sand whiting, Sillago (Sillago) caudicula, is described based on four specimens collected from Oman, the Indian Ocean. It is easily distinguishable from its four known members of the subgenus Sillago by having a smaller head (29.0–30.1% in standard length), 23–24 soft anal fin rays, 35–36 total vertebrae, body depth at the origin of the second dorsal fin slightly deeper than that at the origin of the first dorsal fin, first and second hypurals fused (in adult) or narrowly separated (in young), third and fourth hypurals fused, and 11 dusky midlateral spots on the body.     

Revision of the genusAcanthaphritis (Percophidae) with the description of a new species

The percophid genusAcanthaphritis is reviewed.Spinapsaron andBranchiopsaron are synonymized withAcanthaphritis. The genus is characterized by a barbel on the snout tip in males, a single maxillary spine, cheek scales, ctenoid lateral line scales, prevomerine teeth present, palatine teeth absent, posterodorsal edge of opercular membrane ragged, five dorsal spines and seven branchiostegal rays. Four species (one new) are recognised in the genus:A. grandisquamis, A. barbata, A. ozawai andA. unoorum n. sp. A lectotype is designated forA. grandisquamis. The new species,A. unoorum, is characterized by having 23–25 dorsal fin rays, 28–30 anal fin rays, 37–39 lateral line scales, 37–39 vertebrae, one or two brown spots on the opercle, two longitudinal rows of yellow marks on the body when fresh, two longitudinal dark lines and a longitudinal row of dark marks on the body in males, and a single longitudinal dark line and longitudinal row of dark marks on the body in females.     

<Emphasis Type="Italic">Samariscus multiradiatus</Emphasis>, a new dextral flounder (Pleuronectiformes: Samaridae) from New Caledonia

A new dextral flounder, Samariscus multiradiatus, is described from six specimens (four males and two females) collected in deep waters (296–430 m) around New Caledonia. The species is easily distinguished from its 16 congeners in having a combination of 85–91 dorsal fin rays, 67–72 anal fin rays, 5 pectoral fin rays, and 9 abdominal and 34–35 caudal vertebrae.     

Fossil record of a silurid catfish from the Middle Miocene Sanuki Group of Ohkawa, Kagawa Prefecture, Japan

A fossil specimen identified as a silurid catfish (92.5 mm SL) was collected from the Middle Miocene Sanuki Group (15.8±0.9 Ma) of Ohkawa, Kagawa Prefecture, Japan. This is the oldest certain record of a silurid catfish. Morphological characteristics of the specimen are as follows: 52 or 53 vertebrae, 61 or 62 anal fin rays, a stout, short spine (11%SL) and 10 or more soft rays of the pectoral fin, 8 or more pelvic fin rays, 8 or more branchiostegal rays, head length of ca. 24%SL, and most probably not forked caudal fin. The fossil specimen is clearly distinct from three extant silurids in Japan, and probably belongs to an undescribed form considering its geological age.     

Variation in flexural stiffness of the lepidotrichia within and among the soft fins of yellow perch under different preservation techniques

Although the ray‐finned fishes are named for their bony, segmented lepidotrichia (fin rays), we are only beginning to understand the morphological and functional diversity of this key vertebrate structure. Fin rays support the fin web, and their material properties help define the function of the entire fin. Many earlier studies of fin ray morphology and function have focused on isolated rays, or on rays from only one or two fins. At the same time, relatively little is known about how different preservation techniques affect the material properties of many vertebrate structures, including fin rays. Here, we use three‐point bending tests to examine intra‐ and inter‐fin variation in the flexural stiffness of fin rays from yellow perch, Perca flavescens. We sampled fin rays from individuals that were assigned to one of three preservation treatments: fresh, frozen, and preserved with formalin. The flexural stiffness of the fin rays varied within and among fins. Pelvic‐fin rays were the stiffest, and pectoral fin rays the least stiff. The fin rays of the dorsal, anal, and caudal fins all had similar stiffness values, which were intermediate relative to those from the paired fins. The flexural stiffness of the fin rays was higher in rays that were at the leading edge of the fin. This variation in flexural stiffness was associated with variation in joint density and the relative length of the unsegmented proximal base of the fin rays. There was no significant difference in flexural stiffness between fresh and frozen specimens. In specimens preserved with formalin, there is a small but significant effect on stiffness in smaller fin rays.