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1.
This paper revises and updates taxonomic and distributional information about hagfishes (Myxinidae) from Australia. It covers five species of the genus Eptatretus: Eptatretus cirrhatus known from eastern Australia and also distributed around New Zealand, Eptatretus longipinnis endemic to South Australia, Eptatretus strahani originally described from the Philippines and reported here as a new record from Western Australia and two new species described herein as Eptatretus alastairi and Eptatretus gomoni, both from Western Australia. Eptatretus alastairi is distinguished from all congeners by the unique combination of the following characters: six pairs of gill pouches; three‐cusp multicusps on the anterior and posterior rows of cusps; anterior unicusps 9–12; posterior unicusps 8–11; total cusps 48–56; prebranchial pores 13–16; branchial pores 5–6; trunk pores 50–55; tail pores 11–13; total pores 83–88; two bilaterally symmetrical nasal‐sinus papillae in the dorsal surface of the nasal sinus. Eptatretus gomoni is distinguished from all congeners by the unique combination of the following characters: eight pairs of gill pouches; three‐cusp multicusps on the anterior and two‐cusp multicusps on the posterior row of cusps; anterior unicusps 10–11; posterior unicusps 9–10; total cusps 50; prebranchial pores 12–13; branchial pores 7–8; trunk pores 57–58; tail pores 14–15; total pores 91–93; no nasal‐sinus papillae. An identification key for the Australian species of Eptatretus is also provided.  相似文献   

2.
A new species of seven‐gilled hagfish Eptatretus astrolabium (Myxinidae) is described from a 400 mm total length female trapped 1 km east from Planet Rock, Astrolabe Bay, Papua New Guinea, at c. 500 m depth. This is the first hagfish species reported from the waters around New Guinea. It can be distinguished from other hagfishes by a combination of characters including seven pairs of gill apertures, three‐cusp multicusps on the anterior and posterior rows of cusps, 10 posterior unicusps, 52 total cusps, 18–19 prebranchial pores, five branchial pores, 48–49 trunk pores, 83–84 total pores and no nasal‐sinus papillae.  相似文献   

3.
A single hagfish (Myxinidae, Eptatretus) specimen was recently captured at a hydrothermal vent site on the East Pacific Rise (38 degrees S). This is the first capture of a member of the jawless fishes (agnathans) from a hydrothermal vent site. The specimen differs from all congeners by the very slender body (depth 2.9% of total length), the paired and median ventral nasal sinus papillae, and the presence of 10 afferent branchial arteries on the medial ventral aorta. It is further unique because of a combination of the following features: slime pore counts; paired dorsal nasal sinus papillae; 12 gill pouches and gill apertures; posterior left side of body widely separated from pharyngocutaneous duct; 3/2 multicusp configuration; ventral aorta bifurcated anteriorly between 2nd and 3rd gill pouches (counted from the snout toward the heart); and pink coloration. The specimen is here described as a new species named Eptatretus strickrotti. Molecular 16S rRNA data places this new species as the basal-most species of Eptatretus, providing important new insight to the evolution of hagfishes as a whole.  相似文献   

4.
A new species of Acanthochondria Oakley, 1927 (Copepoda, Poecilostomatoida, Chondracanthidae), parasitic in the pharynx of hagfishes Eptatretus burgeri (Girard), E. sheni (Kuo, Huang & Mok) and E. yangi (Teng), from off Taiwan is described and illustrated. The new species can be distinguished from its congeners by having the neck region longer than wide (about 2–3 times as long as wide), the moderately long protopod of leg 2 (Type E), the endopod of leg 2 as large as exopod, the cephalosome wider than long, the armature formula of antennule (1, 1, 2, 2, 9), the relatively long trunk (6.7 mm) and egg-sacs (14.4 mm). This is the first record of a parasitic chondracanthid from hagfishes. The findings may provide insights into the phylogenetic relationships and interactions among chondracanthids, hagfishes and demersal fishes, but call for further molecular studies.  相似文献   

5.
Two new cutthroat eel species are described from Vietnam. Dysomma intermedium sp. nov. has a relatively long trunk, being about half of head length and anal-fin origin more than twice pectoral-fin length behind the pectoral-fin tip; pectoral fin well developed; dorsal-fin origin over or slightly in front of base of pectoral fin; two intermaxillary teeth; four or five compound teeth on ethmovomer; single row of seven or eight teeth on lower jaw; total lateral-line pores 70–76; and 21 pre-anal and 118–124 total vertebrae. Dysommina brevis sp. nov. differs from congeners by having a trunk shorter than head length, its length 11.1%–11.8% TL; a short pre-anal length 24.6%–25.6% TL, eye diameter 11.8%–12.3% head length; three large and one or two small teeth on ethmovomer; and fewer teeth on the upper and lower jaws. In addition, a specimen representing the first record of Dysommina orientalis in Vietnamese water is documented.  相似文献   

6.
A new species of snake eel (family Ophichthidae, subfamily Ophichthinae), Apterichtus hatookai, is described based on the 478.5 mm holotype and three paratypes, 265.0–519.4 mm in total length (TL), collected from the Pacific Ocean, off the coasts of Shikoku Island and central Honshu Island, Japan. The new species can be distinguished from its congeners, except for Apterichtus monodi and Apterichtus orientalis, by having seven supratemporal pores. The new species is distinguishable from A. monodi by having a longer tail (60.4–62.0 % TL vs. 57.4–60.2 %), four preopercular pores (vs. three), fewer lateral-line pores before the anus (54–58 vs. 63–68), and fewer total vertebrae (137–141 vs. 142–151). Apterichtus hatookai differs from A. orientalis in having a shorter head (5.1–6.1 % TL vs. 7.1–8.1 %; 13.3–16.0 % of preanal length vs. 16.2–18.0 %), a longer tail (60.4–62.0 % TL vs. 54.8–56.0 %), lower body depth at gill opening (0.9–1.5 % TL vs. 1.8–1.9; 2.3–3.8 % of preanal length vs. 4.1–4.2 %), more numerous total vertebrae (137–141 vs. 131–133), and by the anterior tip of the lower jaw below the center of the eye (vs. anterior to a vertical through anterior margin of eye).  相似文献   

7.
A new species of Odontostilbe is described from the rio Jaciparaná, rio Madeira basin, Rondônia, Brazil. Odontostilbe pacaasnovos differs from all its congeners, except O. pequira, by the colour pattern. Additionally, it differs from its congeners by the terminal mouth, number of cusps in the teeth of the premaxilla (5–7), number of branched rays in the anal fin (19–22), by the shape of dentary teeth (5–7 cusps with central cusp larger and longer than laterals cusps) and by the number of lamellae of the olfactory rosette (17–18 in male and 14 in female). Morphological and molecular comparisons corroborate the distinctiveness between O. pacaasnovos and its congeners, justifying its recognition as a new species.  相似文献   

8.

Neoalbionella Özdikmen, 2008 comprises 10 accepted species, which all infect sharks of Squaliformes and Carcharhiniformes. Adult females belonging to species of Neoalbionella, based on the maxillule palp armed with three setae and the maxilliped subchela claw with only one secondary denticle, were collected from sharks off the coast of South Africa. Neoalbionella izawai n. sp. collected from the anterodorsal part of the spiracle opening of Centrophorus moluccensis Bleeker differs from its congeners by having maxillae that are separated except at the tapering tips where they are fused and that are longer than the trunk, uropods originating from the pointed posterior margin of the trunk and that are well developed, and maxillipeds without an additional spine at the base of the subchela barb. Neoalbionella etmopteri (Yamaguti, 1939) is herein reported from two new hosts (Etmopterus spp.) off South Africa.

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9.
Myxine formosana, a new hagfish species, is described on the basis of the specimens from the Pacific Ocean southwest of Taiwan at depths 588–1500 m. It is five-gilled and white-headed with a three-cusp multicusp on the anterior set of cusps and a two-cusp multicusp on the posterior set. Myxine formosana, M. circifrons, M. mccoskeri, and M. robinsi are superficially rather similar, but M. formosana has low to vestigal caudal finfolds. It is the first record of the genus Myxine from Taiwan. Received: October 25, 2000 / Revised: March 17, 2001 / Accepted: April 21, 2001  相似文献   

10.
Hagfishes from New Zealand are reviewed and a phylogeny proposed using morphological and genetic data (DNA sequences of cytochrome c oxidase subunit I gene, COI, and the small subunit RNA, 16S). E ptatretus cryptus sp. nov. was previously confused with Eptatretus cirrhatus (Forster in Bloch & Schneider, 1801) because of their similar morphology, and is found from the Three Kings Islands to Stewart Island and in the eastern part of the Chatham Rise (at depths of 96–922 m). E ptatretus poicilus sp. nov. is endemic to the Three Kings Islands, where it is common and associated with soft sediment and deep‐sea coral‐sponge habitats (114–842 m). N eomyxine caesiovitta sp. nov. is a slender hagfish found along the east coast of the North Island south to the Chatham Rise (430–1083 m). A neotype is erected for E. cirrhatus (type locality: Breaksea Sound, Fiordland), occurring widely in New Zealand coastal, shelf, and slope waters (1–922 m), but not at the Three Kings Islands. Eptatetrus goliath Mincarone & Stewart, 2006, Neomyxine biniplicata (Richardson & Jowett, 1951), and Nemamyxine elongata Richardson, 1958 are further described using additional material. Rubicundus eos (Fernholm, 1991) is still only known from the holotype (type locality: Challenger Plateau). Genetic results showed that the New Zealand Eptatretus species form a monophyletic group within the subfamily Eptatretinae, indicating likely speciation from a single common ancestor within the area. E ptatretus poicilus sp. nov. is the sister species of E. cirrhatus, and E . cryptus sp. nov. is closely associated with the clade formed by these two species. Eptatretus goliath is most closely associated with Eptatretus minor Fernholm & Hubbs, 1981 (Gulf of Mexico), these two species basally diverging within New Zealand hagfishes. The endemic genus Neomyxine forms a well‐supported monophyletic group of as yet uncertain position within the phylogenetic tree. A key to the New Zealand hagfishes, fresh colour photographs, distribution maps, and in situ video recordings are presented. © 2015 The Linnean Society of London  相似文献   

11.
A new species of the genus Awaous (Oxudercidae), Awaous motla sp. nov., is described based on 18 specimens collected from the Mahanadi River near Sonepur, Subarnapur District, and 3 specimens from the same river near Boudh bridge, Boudh District of Odisha, India. This species is distinct from its congeners by having a combination of characteristics: relatively small eyes, diameter of 6.6–8.4 in head length (LH); robust and long snout, 2.0–2.6 in LH; eye diameter 2.7–4.1 in snout length; cephalic sensory pore system interrupted with eight pores; predorsal scales 13–15; longitudinal scale series 55–58; gill rakers 2 + 1 + (6–7) on the first gill arch; teeth small, conical, and in a single row on the upper jaw and multiserial (2–3) on the lower jaw. This species is also differentiated from some of its congeners in the nucleotide composition of the cytochrome c oxidase I gene by 8.3%–13.8% Kimura two-parameter (K2P) distance and belongs to a separate cluster in the maximum likelihood tree analysis. This finding is also supported by the species delimitation analysis based on Assemble Species by Automatic Partitioning. The new species holds high commercial value in its locality and needs special conservation attention for sustainable utilization.  相似文献   

12.
Triplophysa ferganaensis sp. nov. is described from the Shakhimardan stream, a small tributary of the Syr Darya, which does not reach the river in Fergana Valley. It can be distinguished from other valid Triplophysa loaches based on the following combination of characters: body smooth and scaleless, lateral line complete, posterior chamber of air bladder degenerated, inner gill rakers 10–11 on the first-gill arch, outer gill rakers absent, vertebrae 4 + 35–36, 8 + 8 branched caudal-fin rays, caudal peduncle depth 2.1–2.7 times its length, two supratemporal pores, dorsal-fin origin closer to the caudal-fin base than to the snout tip, caudal fin emarginated and pelvic-fin tip reaching the anus. The new species can also be distinguished from its congeners based on the molecular analyses of mitochondrial cytochrome oxidase subunit I (coI) gene sequences. The phylogenetic position of this new species indicates that it is a sister taxon of Triplophysa tenuis.  相似文献   

13.
Argyrosomus japonicus is a member of the family Sciaenidae, which are commonly known as drums and croakers. A. japonicus occurs in estuarine and nearshore Pacific Ocean and Indian Ocean waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan. The biology of A. japonicus is relatively well studied in South Africa, and more recently studied in Australia, but no information is readily available from other areas of its distributional range. The early life history distribution of A. japonicus may differ among regions, with their distribution in estuaries linked to salinity, turbidity, freshwater flows and depth of water. Studies in South Africa and Australia found that juvenile fish grow rapidly, attaining 35 cm TL in 1 year and 87–90 cm TL in 5 years. Sexual maturity also differs among regions and is attained at 2–3 years of age and >50 cm in eastern Australia, 5–6 years of age and >80 cm TL in western Australia and southern Africa. The maximum reported length and age of A. japonicus is 175 cm and 42 years, respectively. Spawning most likely occurs in nearshore coastal waters although there is evidence to suggest that it may also occur in the lower reaches of estuaries. Time of spawning varies among geographic localities and is probably linked to water temperature and oceanography. Juvenile fish (<2 years) appear to be relatively sedentary, but sub‐adults and adults can move relatively long distances (>200 km) and such movements may be linked to pre‐spawning migrations. A. japonicus is important in many recreational and commercial fisheries, but like other sciaenids, is prone to overfishing. It is classified as recruitment overfished in South Africa and overfished in eastern Australia. Although much research has been done to minimize the capture of juveniles in Australian prawn‐trawl fisheries, greater protection of spawners and improved fishing practices to enhance survival of discarded juveniles, particularly from prawn trawling, may be required. An aquaculture industry is developing for A. japonicus in Australia and preliminary research on the impacts and success of re‐stocking wild populations has begun in an attempt to arrest the apparent decline in populations.  相似文献   

14.
Three new species of Hatschekia are described from the gill filaments of fishes taken in the Persian Gulf: H. seyi n. sp. from Heniochus acuminatus (Linnaeus), H. nodosa n. sp. from Lutjanus coccineus (Cuvier) and H. tanysoma n. sp. from L. fulviflamma (Forsskål). H. seyi differs from its congeners in having the cephalothorax longer than the trunk; H. nodosa, in having multiple nodules on the posterolateral margins of the trunk; and H. tanysoma, in having the trunk more than six times the length of cephalothorax and some pinnate setae on legs 1 and 2.  相似文献   

15.
A new species of Hemigrammus is described from the Amazon Basin near Leticia, Departamento Amazonas, Colombia. In common with some congeners and some Hyphessobrycon spp., the new species colour pattern lacks a humeral blotch but has a caudal-peduncle blotch. It can be distinguished from congeners with a similar colour pattern by having: a relatively deep body (30.2%–39.0% LS), 20–24 branched anal-fin rays, 6–8 perforated scales of the lateral line, anal-fin base without a conspicuous black stripe, 3–5 maxillary teeth, maxillary teeth with 1–3 cusps, a thin longitudinal midlateral line and a well-defined oval shaped caudal blotch, extending from caudal peduncle into the lower caudal-fin rays. Comparisons with congeners and with Hyphessobrycon species sharing the same general colour pattern are presented.  相似文献   

16.
A new species of the genus Cirrhimuraena (Anguilliformes: Ophichthidae), Cirrhimuraena indica sp. nov., is described based on eight specimens collected from the Paradip (Odisha) and Petuaghat harbours (West Bengal) along the Bay of Bengal. The species is distinct in having the upper jaw fringed with 16–17 cirri before posterior nostril and 4–5 in between the anterior and posterior nostrils on the side; dorsal fin originates above the level of gill opening, predorsal length is 9.3–10.9 in total length; the head is relatively large, the length is 9.3–9.8 in total length; no infraorbital pores are observed between the nostrils; teeth are numerous, small, conical and in bands on each jaw; pores are present before the gill opening 10–11 and before anus 47–48; pectoral-fin length is 2.4–2.8 in head length; predorsal vertebrae are 8–10, pre-anal vertebrae 43–47 and total vertebrae 164–169. In the maximum likelihood tree analysis for COI gene, the new species belongs to the same clade as the other congener of Cirrhimuraena chinensis and is separated from the species morphologically and genetically.  相似文献   

17.
Hatschekia khahajya n. sp. is described from the gill filaments of two monacanthid fishes, Cantherhines dumerilii (Hollard) and Amanses scopes (Cuvier), caught off Okinawa, Japan. The new species can be distinguished from its congeners by the possession of the following combination of characters: cephalothorax length/trunk length ratio greater than 0.40; cephalothorax with a pair of lateral bars on the chitinous ring and a posterior pair of surface ridges; trunk with a bifurcate chitinous frame extending over its anterior third and with well-developed posterior lobes that extend beyond the abdomen; and four processes plus two spinular rows on the distal margin of the intercoxal sclerite of legs 1 and 2.  相似文献   

18.
It is known that in eight hagfishes chromosome elimination occurs during early embryogenesis. The eliminated chromosomes are mostly C-band positive, so that none of the somatic cells have any C-band-positive chromatin. Recently, some highly repetitive DNA sequences have been reported as eliminated elements in these hagfishes based on molecular biological methods. However, no germline-restricted repetitive DNA have been directly isolated from the Japanese hagfish Eptatretus burgeri, from which approximately 21% of the total DNA is eliminated from presumptive somatic cells. Through electrophoretic investigation after digestion with restriction endonucleases, two DNA families that are restricted to germline DNA were isolated. Molecular cloning and sequence analysis revealed that these families are composed of closely related sequences of 64 and 57bp in length, respectively. Southern blot hybridization revealed that the two DNA families are restricted to germline DNA and were thus named EEEb1 and EEEb2, respectively. Moreover, these eliminated elements were highly and tandemly repeated, and it is predicted that they might amplify by saltatory replication and have evolved in a concerted manner. By densitometric scanning, EEEb1 and EEEb2 were found to amount to make up approximately 18.5 and 0.024% of the total germline genomic DNA, accounting for 88.6% of the total eliminated DNA. A fluorescence in situ hybridization experiment demonstrated that EEEb1 is located on all C-band-positive chromosomes that are limited to germ cells, suggesting that EEEb1 is the primary component of eliminated DNA of E. burgeri.  相似文献   

19.
《Journal of bryology》2013,35(4):304-306
Abstract

A new species of Crossidium (Pottiaceae, Bryophyta), C. karoo, is described for South Africa. It uniquely differs from congeners in tight encapsulation of the photosynthetic filaments by the clasping upper lamina.  相似文献   

20.
This study investigates length–weight and length–length relationships of four shad species (Alosa caspia caspia, Alosa immaculata, Alosa maeotica, Alosa tanaica) captured in the western Black Sea coast of Turkey. A total of 686 specimens, 355 females and 331 males, were caught by gill net, trammel net and longline from 2006 through 2007 along the western Black Sea coast of Turkey. The relationships of total length (TL), fork length (FL) and standard length (SL) are presented for inhabiting in the Black Sea four shad species and the relationships between total length (TL) and body weight (BW) from the two localities, Sile and Karasu in the western Black Sea coast of Turkey. The Length–weight relationships generally indicated positive allometric growth in Alosa species for both males and females and an isometric growth for A. immaculata females. The coefficient b ranged from a minimum 2.97 for females of A. immaculata to a maximum 3.75 for both sexes A. c. caspia. Results indicated that the length–length relationship between the three length measurements were highly correlated (r2 > 0.99, P < 0.001).  相似文献   

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