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1.
A chub of previously ambiguous identity from the Boljunscica and Pazincica rivers (south-eastern Istra Peninsula) was studied and compared with geographically close Squalius squalus, Squalius zrmanja, and Squalius janae recently described from the Dragonja River drainage in the Adriatic Sea basin in Slovenia. It was shown that the chub from the south-eastern Istra Peninsula differs from all know species of Squalius but one: Squalius janae. Three samples examined from Boljunscica and Pazincica rivers and Squalius janae from its type locality, Dragonja River, show the following characters typical for the latter species: a long head (the head length 27–32% SL); a pointed conical snout with a clearly projecting upper jaw; a long straight mouth cleft, the lower jaw length (39–45% HL) exceeding the caudal peduncle depth; a large eye; commonly 9? branched anal-fin rays; commonly 44 total vertebrae (24+20 or 25+19); bright silvery colouration, scales easily lost; iris, pectoral, pelvic and anal fin pigmentation with yellow shades. The data on the distribution of Squalius chubs in the northern Adriatic basin support the assumption that the range of Squalius janae is determined by the geology of the Trieste Flysch Basin and the Pazin Flysch Basin forming the base of the Istra Peninsula. The distribution pattern of this species does not support a simple model of fish dispersal and a complete connectivity within the whole Palaeo-Po historical drainage. Indeed, it indicates a disrupted surface palaeohydrography that was heavily fragmented by karstification in the whole Dinaric area.  相似文献   

2.
Taxonomic analysis of a group of morphologically similar ponyfishes (Perciformes: Leiognathidae) establishes a complex comprising three valid species: Leiognathus aureus Abe and Haneda, 1972, widely distributed in the western Pacific Ocean (Taiwan, Philippines, Thailand, Singapore, Indonesia, and northern Australia); L. hataii Abe and Haneda, 1972, currently known only from Ambon, Indonesia; and L. panayensis sp. nov. Kimura and Dunlap, currently known only from Panay Island, the Philippines. The L. aureus complex can be defined by the following combination of characters: mouth protruding forward, not downward; small but sharp conical teeth uniserially on jaws; a black line between lower margin of eye and lower jaw articulation; and lateral line incomplete, ending below posterior part of dorsal fin base or on anterior caudal peduncle. Leiognathus hataii differs from both L. aureus and L. panayensis in having a large dark blotch below the spinous dorsal fin base and fewer counts of scales (lateral line scales 50–58 vs. 64–85 in the latter two species; scales above lateral line 7–10 vs. 12–18; scales below lateral line 22–26 vs. 30–41). Leiognathus panayensis is distinguished from L. aureus in having a deeper body (41–51% SL vs. 35–45% SL in the latter), long posterior limb of maxilla (21–25% HL vs. 15–23% HL), wholly scaled belly (vs. naked along preanal median keel), and a dark blotch on nape (vs. absent).  相似文献   

3.
The Dalmatian cyprinid genus Phoxinellus is characterized by reductive characters most likely associated with the environmental conditions of small karstic streams, where all species of this genus occur. Based on 33 morphological traits, nuclear and mtDNA sequences Phoxinellus was found to be paraphyletic and included three not closely related monophyletic units. The scientific name Phoxinellus should therefore be restricted to species having plain coloration, small or absent postcleithrum, no genital papilla and an almost entirely naked body such as P. alepidotus, P. dalmaticus, and P. pseudalepidotus. Species that also have a small or absent postcleithrum and no genital papilla but display a dark stripe from the head to the caudal peduncle, and are entirely covered by distinct, not overlapping scales should be positioned closely to Telestes. Thus, we suggest inclusion of Phoxinellus croaticus, P. fontinalis and Paraphoxinus metohiensis in the genus Telestes. The Phoxinellus species that have a irregularly spotted color pattern, a large postcleithrum, an increased number of precaudal anal-fin pterygiophores, and a large genital papilla in females represent its own evolutionary line closely related to the Balkan species of Pseudophoxinus. For this monophyletic group, we propose to introduce a new genus: Delminichthys. This genus includes the species D. adspersus, D. ghetaldii, D. krbavensis and D. jadovensis.  相似文献   

4.
Two new species of Leporinus are described from tributaries of the Rio Amazonas in Brazil. One species is known from the Jari and Tapajós River basins, and is identified on the basis of a gas bladder reduced in size, a dark midlateral stripe on the body, dark transverse bars on the dorsum, a subinferior mouth, three teeth on the premaxilla, four teeth on the dentary and 16 scale rows around the caudal peduncle. The second new species is known from the Tocantins, Xingu and Tapajós River basins, and is identified on the basis of three dark longitudinal stripes on the body, a subinferior mouth, three teeth on the premaxilla, four teeth on the dentary and 12 scale rows around the caudal peduncle. In addition, Leporinus striatus is redescribed based on type and additional specimens from the Río de La Plata, Amazonas, Orinoco, Atrato, Magdalena and Sinu River basins. Leporinus striatus is identified on the basis of four dark longitudinal stripes on the body, a subterminal mouth, three teeth on the premaxilla, four teeth on the dentary and 16 scale rows around the caudal peduncle.  相似文献   

5.

Priolepis duostella sp. nov. (Perciformes: Gobiidae) is described based on a single specimen of 28.8 mm in standard length collected from an artificial reef released established for 2.5 years in ca. 100 m depth off Kashiwa-jima Island, Kochi, southern Japan. Within the three species grades of the genus, the new species is included in the “Priolepis profunda” grade, characterized by the presence of predorsal scales and well-developed transverse papillae rows on the cheek. The new species can be clearly distinguished from congeners by its distinctive coloration, including two black blotches, each crossed by a vertical white stripe, on the caudal fin, four white stripes on the head, and six white bars on body, the second bar curved, continuous with the anteriormost diagonal stripe on the first dorsal fin, the third bar bent at the middle, originating on the second dorsal-fin origin, and the fourth bar curved. Although most similar in coloration to Priolepis akihitoi Hoese and Larson 2010, the new species can be distinguished from the latter by the following: a large eye, its diameter 31.4% of head length (HL) (vs. 26.1–30.3), a wide interorbital space, its width 10.9% HL (vs. 5.3–7.8), six bars on the body, second to fourth curve or bent (vs. eight, all straight), black blotches on the lower caudal fin (vs. absent), and three anterior transverse interorbital papillae (ATI) (vs. one or two); and four or five posterior transverse interorbital papillae (PTI) (vs. one or two).

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6.
Two new species of Hyphessobrycon are described from the headwaters of the Tapajós and Xingu River basins, Pará, Brazil. Both new species can be distinguished from congeners by the presence of a vertically elongate humeral blotch, a conspicuous round to vertically oblong caudal‐peduncle blotch not extending onto the distal portions of the middle caudal‐fin rays, a conspicuous blotch on the central portion of the third infraorbital immediately ventral to the eye, the lack of a conspicuous longitudinal stripe and the lack of sexual dimorphism in the extension of the caudal‐peduncle blotch. Hyphessobrycon delimai n. sp. can be distinguished from Hyphessobrycon krenakore n. sp. by the extent of the caudal‐peduncle blotch which extends across most of the caudal‐peduncle depth (v. restricted to the middle portion of the caudal peduncle), the presence of dark chromatophores uniformly scattered along the length of the interradial membranes of the dorsal, anal and caudal fins (v. concentrated on the distal one‐half or one‐fourth of the interradial membranes) and the absence of small bony processes on the pelvic and anal fins of mature males (v. small bony processes present).  相似文献   

7.
A new species of the subfamily Barbinae, Tor yingjiangensis, is recognized from Yunnan province, China. It can be distinguished from other Tor species by the following combination of characters: last simple dorsal-fin ray osseous and non-serrated; no forward directed predorsal procumbent spine; head length considerably longer than body depth; no tubercles on the snout or sides of the face; 18–20 gill rakers on the outside of first gill arch; 24–26 lateral line scales; median lobe of lower lip short, its posterior margin truncate, not extending to the vertical across the inner corners of the mouth; and the condition of the lower lip consistent in individuals of different sizes. The new species has been misidentified previously as Tor putitora (Hamilton, F. 1822. An account of the fishes found in the River Ganges and its Branches. Edinburgh & London. 405 pp), which occurs in the Ganges and Indus River basins. The new species can easily be distinguished from T. putitora by having 3–3.5 (vs. 2.5) scales from lateral line to pelvic-fin origin, shorter caudal peduncle length (13.0% vs. 17.2% of standard length), lesser body depth (26.4% vs. 24.0% of standard length) and longer caudal peduncle depth (12.0% vs. 10.9% of standard length), no longitudinal stripe present along side of body, and eyes visible in ventral view of head.  相似文献   

8.
Astyanax anai, a new species of characid fish, is described from the Sixaola River basin, eastern Costa Rica–western Panama, Central America. The new species can be distinguished from all other congeners by the following combination of characters: premaxillary teeth 4–5 at the inner series and 4–6 at the outer series; maxillary teeth tricuspid, 2–4; predorsal scale series irregular and incomplete, with an unscaled space behind tip of supraoccipital process and 12–14 scales; lateral line scales 34–39; humeral region with a conspicuous black and rounded to horizontally ovate spot and two diffuse brown and vertically elongate bars (the first through the rounded to horizontally ovate spot, the second 2–4 scales behind the first); body depth 36·6–42·3% of standard length (LS); midlateral stripe formed by a series of 10–14 anteriorly‐directed dermal herringbone, or chevron‐shaped, marks, most apparent in juveniles and in preserved specimens, extending above the lateral line from the black humeral spot or just behind it (from the second vertical bar) to the caudal peduncle; scale rows from lateral line to base of first dorsal‐fin ray 8–9; scale rows from lateral line to base of pelvic fin 7–8; pre‐anal distance 53·9–61·9% of LS; total anal‐fin elements 29–33; caudal spot elongated, rhomboid or rectangular, with its anterior margin surpassing the middle of the caudal peduncle, usually reaching the anal‐fin insertion, posteriorly covering 4–7 principal caudal‐fin rays and not extending onto the ventral and dorsal margins of the caudal peduncle, covering 3–5 horizontal scale rows. In order to test the phylogenetic relationships of the new taxon in relation to the other North and Central American species of the genus, a new phylogenetic hypothesis based on a reanalysis of the morphological matrix by Schmitter‐Soto (2016) is proposed. A key to the lower Central American (southern Nicaragua to eastern Panama) species of Astyanax is also provided.  相似文献   

9.
Pempheris gasparinii sp. n. is described from five specimens, 59.1–68.0 mm in standard length. It is only known to occur in the shallow reefs of Trindade Island, 1200 km east of the Brazilian coast, in the southwestern Atlantic. Pempheris gasparinii is the third recognized species of Pempheris in the Atlantic Ocean. This new species is morphologically similar to its close relative, Pempheris poeyi, differing by the number of lateral-line scales (51–54 in Pempheris gasparinii vs. 47–49 in Pempheris poeyi), scales below lateral line (10–11 vs. 9), circumpeduncular scales (11–12 vs. 13), head and caudal peduncle lengths (2.7–3.3 vs 3.5–4.0 in head length). Moreover, Pempheris gasparinii shows a 4% genetic divergence from Pempheris poeyi at the cytochrome oxidase I locus (COI), consistent with a lineage split at the beginning of the Pleistocene. This new species represents the 12th endemic fish species from Trindade Island.  相似文献   

10.
A new species of Astyanax from the Rio Paraguaçu basin, Bahia, Brazil, is described. This new species is distinguished from its congeners known to occur in Brazilian drainages by the presence of small bony hooks on all fins of mature males. Furthermore, the new species can be diagnosed by its colour pattern, which consists of a unique vertically elongated humeral blotch, a conspicuous dark drop‐shaped horizontal blotch over the caudal peduncle, tapering anteriorly and not extending to the median caudal‐fin rays, and by the absence of a conspicuous broad dark midlateral stripe. The new species differs further by having the greatest body depth just anterior to the dorsal‐fin origin, 32–35 perforated scales in the lateral line and a reduced number of branched anal‐fin rays (16–20). Apparently, the new species does not fit into any species complex of Astyanax. The occurrence of bony hooks on all fins of Astyanax is discussed.  相似文献   

11.
Sculpins from mountain tributaries of the upper reaches of the Rhone River (Haute-Savoy district) in the collection of the National Museum of Natural History (Paris, France) are described as a new species Cottus sabaudicus. This species belongs to the species group C. gobio, but is characterized by several morphologically specific features. It differs from the typical species of the genus C. gobio in its monotonous body coloration, an increased postanal distance that equals preanal distance, an absence of dark stripes on ventral fins, the ratio of the length of caudal peduncle and depth (1.8–2.3 versus 2.3–2.8), and a greater number of pores in the trunk seismosensory canal (34–37 versus 31–33 + 1).  相似文献   

12.
Two new species of the sciaenid genusNibea are described;N. squamosa from northern Australia and Papua New Guinea andN. microgenys from northern Australia. Both species differ from all known congeners in having a small, inferior mouth, with the lower jaw teeth uniform in size.N. squamosa is distinguished fromN. microgenys by a higher number of lateral line scales (57–60 vs. 48–50), the last pleural rib on the 11th vertebra (vs. 10th), and a longer and more slender caudal peduncle (length 25.9–30.4%SL, depth 6.3–7.9% SL vs. 21.5–26.3, 8.0–10.3).N. squamosa exhibits hyperostosis in some elements, such as the frontals and dorsal and anal pterygiophores.  相似文献   

13.
A new species of hillstream loach Balitora eddsi is described from the Karnali River drainage in south‐western Nepal. The new species is distinguished from all its congeners by possessing the following combination of characters: six to seven unbranched pectoral‐fin rays, pelvic‐fin length 12–14% standard length (LS), dorsal surface without circular or irregular shaped dark blotches, snout pointed, median lobe between anterior rostral barbels pointed posteriorly, dorsal‐fin origin posterior to pelvic‐fin origin, lateral line scales 66–67, caudal peduncle length 22–23·2% LS, caudal peduncle depth 4·1–4·2 times its length.  相似文献   

14.
Molecular data inferred from three nuclear DNA regions were used to re-examine the phylogenetic position and taxonomic status of former Phoxinellus taxa. Using either distance method, maximum likelihood or MCMC, phylogenetic tree revealed statistically well supported clade of Delminichthys adspersus, Delminichthys ghetaldii, Delminichthys jadovensis, and Delminichthys krbavensis occupying a sister position to Pelasgus prespensis; furthermore, Phoxinellus pseudalepidotus emerged as a sister taxon to Delminichthys–Pelasgus group. There was a moderate support for sister relationship between Telestes croaticus and Telestes fontinalis, while the position of Telestes metohiensis varied depending on the region and method used. The topology of taxa within Delminichthys was weakly supported and remained pretty much unresolved. Our results confirm a previous notion that the former genus Phoxinellus is not a monophyletic group but rather a grouping of independent lineages.  相似文献   

15.
A new species of Megaleporinus is described from the Rio de Contas, a coastal drainage of eastern Brazil, and its phylogenetic relationships are studied using molecular data. The new species is unique among Anostomidae by possessing two exclusive features: an irregular dark longitudinal stripe from supracleithrum to second midlateral blotch and anterior cranial fontanel partially closed. In addition, the new species is diagnosed by having three premaxillary teeth, three dentary teeth, 37 or 38 scales in lateral line, 16 scale rows around caudal peduncle, three dark midlateral blotches on body, and red fins in life. The new species is closely related to M. obtusidens from the São Francisco basin, corroborating previous studies that indicated that the latter represents a species complex as currently defined. The new species exhibits the first rib enlarged in mature males, a feature described for some congeners. The new species is herein considered to be Endangered under the IUCN criteria.  相似文献   

16.
蛇鮈属一新亚种记述   总被引:1,自引:0,他引:1  
蛇(鱼句)属为一群小型鲤科鱼类.蛇(鱼句)广泛分布于东亚大陆.通过对采自云南程海和珠江、闽江、长江、辽河、松花江等水系蛇标本的形态、度量特征进行仔细分析和比较,认为蛇程海种群是蛇的1个新亚种,命名为程海蛇(Saurogobio dabryi chenghaiensis).程海蛇(鱼句)的特征为:吻皮发达,盖过上唇;上下唇布满发达的乳突;体及尾柄极细长,体高为体长的12.7%~15.0%,尾柄高为体长的5.5%~6.1%、为尾柄长的31.8%~39.1%;沿体侧中轴自鳃孔上方至尾鳍基具一浅色暗纹,其上布有6~11个大型棒状黑斑(黑斑长为宽的2~4倍);肛门位于腹鳍长度的中点之后;尾鳍最长鳍条为其最短鳍条的2倍以上;仅分布于云南程海.  相似文献   

17.
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.  相似文献   

18.
A new species of soldierfish, Ostichthys spiniger, from off northern New Ireland, Papua New Guinea, is described on the basis of a single specimen collected with a trawl at 180-181 m depth near Kavieng. The new species is characterised by the following characters: scales above lateral line to mid-base of spinous portion of dorsal fin 31/2; no half-scale present anterior to first lateral-line scale; dorsal profile of head nearly uniformly convex; anterior end of each nasal bone with a sharp, forwardly directed spine; a strong spine at the corner of preopercle, which is significantly larger than other serrations; pectoral-fin rays 17; lateral-line scales 29; gill rakers 8 + 13; last dorsal-fin spine shorter than penultimate spine; body depth 2.2 in SL; HL 2.4 in SL; snout very short, 6.6 in HL; least depth of caudal peduncle 4.9 in HL. The new species is compared with other species in the genus. A revised key to the species of Ostichthys is presented. The new species is most similar to O. acanthorhinus.  相似文献   

19.
Pseudophoxinus burduricus sp. n. is described from drainages of Salda and Burdur lakes, southwestern Turkey. It is distinguished from other Anatolian Pseudophoxinus by a combination of characters: lateral line incomplete, with 21–39 (commonly 26–37) perforated scales and 47–57+1-2 scales in lateral series; 10½–12½ scale rows between lateral line and dorsal fin origin, 3–4(5) scale rows between lateral line and the pelvic fin origin; dorsal fin commonly with 7½ branched rays; anal fin commonly with 6½ branched rays; 7–8(9) gill rakers on the first branchial arch; a faint and diffuse epidermal black stripe from eye to caudal fin base in alive and preserved individuals; mouth slightly subterminal, tip of mouth cleft on about level of lower margin of eye; snout rounded, its length greater than eye diameter. Comparison is given with all Pseudophoxinus species from western Anatolia.  相似文献   

20.
A new species of the genus Sturisoma from the Madre de Dios River, upper Madeira, Peru, is described. The new species can be differentiated from its congeners by the following characteristics: dorsolateral stripe reaching to less than half, or only half length of caudal peduncle (v. absence of dorsolateral stripe or, if present, spanning more than half caudal‐peduncle length); premaxillary teeth longer than dentary teeth (v. dentary teeth longer); sexually mature adult males having well‐developed odontodes on the sides of the head and a broader snout (v. adult males lacking well‐developed hypertrophied odontodes or, if present, rostrum is same width as females' or immature males'); by having the ventral portion of the rostrum conspicuously darker than ventral surface of the body (v. rostrum light, with same colour as ventral portion of body, except in Sturisoma barbatum); by lacking the lateral process of the sphenotic (v. lateral process of sphenotic well‐developed, except in Sturisoma tenuirostre); a dark spot on the first three branched pectoral‐fin rays (v. brown spot absent, except in S. barbatum); and the frontal bone contributing less than half of dorsal border of the orbital ridge (v. extensive participation of the frontal, except in Sturisoma guentheri). Furthermore, the new species has 18–20 plates in the median series, which differentiates it from Sturisoma rostratum (21–22), and Sturisoma monopelte (21); and 14–15 coalescent plates, which differentiates it from S. tenuirostre (16–17). It is further differentiated from Sturisoma brevirostre by presence of an enlarged rostrum (v. rostrum not enlarged). A discussion regarding status of the type series and geographic distribution of Sturisoma rostratum is offered, and an identification key for all Sturisoma species is presented.  相似文献   

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