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1.
2.
The osteological development of the vertebral column and fins in shi drum Umbrina cirrosa was studied in order to improve knowledge for its introduction in Mediterranean aquaculture. The osteological development was studied in 171 individuals, of total length (LT) from 2·7 to 30·2 mm that were reared under the mesocosm technique. Vertebral ontogeny starts at 3·4 and 4·0 mm LT, with the formation of the first cartilaginous neural and haemal arches, and spines, respectively, and is completed with the full attainment of epicentrals (12·5 mm LT). The formation of vertebral centra occurs between 4·1 and 7·4 mm LT. Pectoral supports are the first fin elements to develop (3·0 mm LT), followed by those of the caudal fin (3·8 mm LT), pelvic fin (3·9 mm LT) and finally by those of the dorsal and anal fins (4·5 mm LT). The caudal fin is the first to develop fin rays and attain the full count of principal fin rays (4·5–6·8 mm LT), but the last to be fully completed with the formation of procurrent fin rays (6·9–17·5 mm LT). The next fins starting to present rays are the dorsal (5·3 mm LT) and the pectoral fins (5·6 mm LT), while the anal and pelvic fins are the last (5·7 mm LT). Following the caudal principal fin rays (6·8 mm LT), the dorsal, anal (6·9 mm LT), pelvic (7·4 mm LT) and pectoral fins (9·8 mm LT) are the next with fully completed ray counts. Aggregation of qualitative changes, such as the appearance of cartilages, the beginning and the complement of the ossification process and the full complement of elements in U. cirrosa were measured as cumulative frequency counts. These measurements reveal three ontogenetic intervals: one very developmentally active period during early life stages (from 3 to 5·9 mm LT), a second slower developmental period (from 6·0 to 8·9 mm LT) and finally a period of ontogeny more focused on structure refinement up to metamorphosis and settlement (>9·0 mm LT).  相似文献   

3.
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   

4.
 This study redescribes Bregmaceros mcclellandi Thompson, 1840, based on one specimen (74.4 mm SL) from the Bay of Bengal and 66 specimens (30.0–84.7 mm SL) from Mumbai (Bombay), India, because the type specimens have apparently been lost. The present specimens are characterized by having black dorsal, pectoral, and caudal fins and show the following morphology: caudal fin slightly forked; body chromatophores present mainly at the dorsal part; no scales on cheek; vertebrae 52–55 (13–15 + 38–41); dorsal rays 52–59; anal rays 54–60; pectoral rays 18–20; caudal rays 27–31 (principal rays 14); transverse scales 14–15. In the 66 Mumbai specimens, it was confirmed that the distinctive black fin pigmentation developed sequentially with growth, with complete pigmentation first on the anterior lobe of the dorsal fin, then simultaneously on the posterior lobe of the dorsal fin, the caudal fin, and the pectoral fin, and last, on the anal fin. This species is known only from the Arabian Sea, Bay of Bengal, and Gulf of Thailand. A review of 16 nominal Bregmaceros species indicates that, besides B. mcclellandi, the distinctive dark fin pigmentation is found in B. atripinnis (Tickell), B. atlanticus Goode and Bean, B. japonicus Tanaka, and B. lanceolatus Shen. B. atripinnis is considered a junior synonym of B. mcclellandi, and the others are clearly distinct from B. mcclellandi. Comments are made on some of the characters to more fully characterize the species and for reference in future revisionary and phylogenetic studies. Received: June 17, 2002 / Revised: December 2, 2002 / Accepted: December 24, 2002  相似文献   

5.
The taxonomy of French ninespined sticklebacks (Pungitius spp.) has long been controversial. To clarify the taxonomy in this group, we use mitochondrial (COI) and nuclear (RNF213) sequence markers, as well as morphological data. In France, both genetic markers discriminate three evolutionary lineages. Morphological analysis on fresh and type specimens supports the different lineages and the existence of three species in France. Pungitius pungitius, occurring in the North of France and Rhone basin, is characterized by specimens longer than 35 mm SL, by a flat head with a straight or slightly concave snout, typically 9–10 dorsal spines, 10–11 dorsal soft rays, 9–10 anal soft rays, 0–12 scutes on the caudal peduncle with a keel reaching the last anal‐fin ray, longer pelvic fin, post‐dorsal and caudal peduncle lengths, and a slim caudal peduncle (caudal peduncle depth/length 11.8%–21.9%). Pungitius laevis, occurring in France, in the English Channel basins and Loire drainage, differs from the other species by a head rounded with concave snout in specimens longer than 35 mm SL, accentuating the impression of fleshy lips, 0–4 scutes on the caudal peduncle and a higher caudal peduncle depth/length ratio (15.7%–34.5%). Finally, Pungitius vulgaris, endemic to the Vienne River and rivers of south‐western France as far north as the Garonne estuary, is differentiated by a rounded head with a straight or slightly convex snout, the absence of scutes on the caudal peduncle and by having 11 pectoral‐fin rays. Our data confirm the existence of a hybridization zone in the North of France between P. pungitius and P. laevis. As a result, Pungitius lotharingus is invalid, as it was described based on hybrid specimens. A lectotype for P. laevis was designated because the syntypes included hybrids. This revision provides new perspectives for evolutionary biology studies and will have consequences for Pungitius conservation in France.  相似文献   

6.
Two new shrimp-associated gobies,Amblyeleotris yanoi sp. nov. andA. masuii sp. nov. are described on the basis of specimens from Iriomote-jima Island and Okinawa-jima Islands, Okinawa Prefecture, Japan.A. yanoi is distinguished from other members of the genus by the combination of the following characters: 14 anal fin soft rays, 19 pectoral fin rays, 97–103 longitudinal scales, a candle flame-shaped marking on the caudal fin, a very low membrane connecting the pelvic fins and absence of a ventral frenum.A. masuii differs from all other congeners by having 92–97 longitudinal scales, the length of the interpelvic connecting membrane relative to the longest pelvic fin ray (0.43–0.66), black blotches on the sides of the chin, and blue spots on the opercle and preopercle.  相似文献   

7.
Channa nox, a new channid fish lacking a pelvic fin from Guangxi, China   总被引:1,自引:1,他引:0  
 A new species of channid fish, genus Channa, is described from 7 specimens collected from the vicinity of Hepu, Guangxi Province, southern China. The new species, Channa nox, is distinguished from all other channid species by the following combination of characters: absence of pelvic fins, small rounded head (22.1%–26.8% SL), narrow interorbital width (19.6%–26.7% HL), short snout length (3.6%–5.1% SL), predorsal and prepectoral lengths (26.9%–28.4% SL and 24.8%–28.3% SL, respectively), 47–51 dorsal fin rays, 31–33 anal fin rays, 55–63 lateral line scales, 5.5–6.5 scales above lateral line, 9–13 cheek scales, 53–55 total vertebrae, 1 or 2 scale(s) on each side of lower jaw undersurface, the black upper half of body with 8–11 irregular (often anteriorly pointed V-shaped) bands or blotches, a large white-rimmed black ocellus on caudal peduncle and sparse white spots on the dark brown body and dorsal and caudal fins, as well as the shape of the hyomandibular process of the suprabranchial organs. Channa nox is sympatrically distributed with its morphologically most similar congener, C. asiatica. Received: January 18, 2001 / Revised: November 2, 2001 / Accepted: December 12, 2001  相似文献   

8.
Psilorhynchus ngathanu, a new psilorhynchid species, is described from the Dutah River, Chindwin Basin in Manipur, India. The new species is distinct from its congeners in the absence of scales from the midventral region between the pectoral fins, the presence of two rows of spots on the dorsal-fin rays and two black bars on the caudal fin, v–vi unbranched pectoral-fin rays, and 10 + 9 principal caudal-fin rays.  相似文献   

9.
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   

10.
Two new species and a new record of Sinogastromyzon are described from Lixianjiang River of Yunnan province, China. Sinogastromyzon lixianjiangensis, new species, can be distinguished from its congeners by the following characters: pectoral fin with XIII–XIV, 15–17 rays; pelvic fin with X–XI, 10–12 rays; 60–65 lateral-line scales; no scales on the dorsum of paired fins or the region between axilla of pectoral fin and pelvic-fin origin; tip of pelvic fin close to anus; tip of anal fin close to caudal-fin base; anal-fin origin nearer to the caudal-fin base than to the posterior pelvic-fin base; anus nearer to anal-fin origin than to the posterior pelvic-fin base; dorsal side of the body with 9–11 black blotches. Sinogastromyzon macrostoma, new species can be distinguished from its congeners by the following characters: pectoral fin with XII–XIV, 12–15 rays; pelvic fin with VII–IX, 11–13 rays; 48–56 lateral-line scales; mouth extremely big, slightly arched; no scales on the dorsum of paired fins or the region between axilla of pectoral fin and pelvic-fin origin; tip of pelvic fin far beyond anus; tip of anal fin far from caudal-fin base; anal-fin origin about midway between the posterior pelvic-fin base and caudal-fin base; anus nearer to posterior pelvic-fin base than to anal-fin origin; dorsal side of the body uniformly gray, without regular blotches in formalin preserved specimen. Sinogastromyzon cf. multiocellum is firstly recorded in China.  相似文献   

11.
A new genus and species of the subfamily Bythitinae (Bythitidae),Hastatobythites arafurensis, is described on the basis of two specimens from the Arafura Sea. The genus is unique in the subfamily in having two anteriorlydirected spines, one on the frontal and one on the mesethmoid. It is also distinguishable from all other genera in the subfamily by the following combination of characters: head scales absent; squamation on body incomplete; maxillary expanded posteriorly; no thin pore-bearing skin flap over opercle; opercle thin, weak, without distinct spine; jaw teeth conical; vomerine and palatine teeth present; developed gill rakers on 1 st arch 3; pelvic fins with 1 ray in each; pectoral peduncle elongated, with 16 rays; caudal fin rays 12; branchiostegal, rays 8; precaudal vertebrae 15, with tips of 6th to 12th neural spines truncated.  相似文献   

12.
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.  相似文献   

13.
The bembrid genusBembras Cuvier is reviewed. Five species,B. japonica Cuvier,B. adenensis Imamura & Knapp and three undescribed species, were assigned to the genus. Type species of the genus,Bembras japonica is redescribed on the basis of 36 specimens including the holotype, and three new species,B. macrolepis, B. longipinnis andB. megacephala, previously misidentified asB. japonicus, are also described on the basis of specimens collected from Australia and Indonesia.Bembras macrolepis differs from its congeners by having large body scales, a long pectoral fin with 17–19 rays and a dark blotch on slightly upper portion to middle of margin, 14–15 anal-fin rays, small head and orbit, and caudal fin with a broad vertical dark band near posterior margin.Bembras longipinnis is distinguished from other members of the genus by having a slightly long pectoral fin with 17–19 rays and lacking a small black blotch near tip of upper rays, caudal fin with a large dark spot most intense in lower lobe, 1–2 gill rakers on upper gill arch, 13–14 anal-fin rays, slightly elong ated head and small orbit.Bembras megacephala is characterized by the following combination of characters: caudal fin with several irregular narrow vertical dark bands, small orbit, pectoral fin with 19–20 rays and lacking a small black blotch near tip of upper rays, head elongate, 2–4 gill rakers on upper gill arch, 15 anal-fin rays and small body scales. A key separating the five species ofBembras is given.  相似文献   

14.
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.  相似文献   

15.
Previous research on the osteology of the Gobiesocidae focused mostly on the neurocranium and the thoracic sucking disc (formed by the paired‐fin girdles). Little attention has been paid to the skeleton of the median fins. The dorsal‐ and anal‐fin skeleton of Lepadogaster lepadogaster and other gobiesocids (excluding Alabes, which lacks these fins) are characterized by the absence of spines, branched fin‐rays, and middle radials. In gobiesocids, the distal radials never ossify and consist of elastic hyaline‐cell cartilage. Gouania wildenowi is unique among gobiesocids in having further reductions of the dorsal‐ and anal‐fin skeleton, including a notable decrease in the size of the proximal‐middle radials in an anterior–posterior direction. Unlike L. lepadogaster, which exhibits a one‐to‐one relationship between the dorsal‐ and anal‐fin rays and proximal‐middle radials, G. wildenowi has a higher number of proximal‐middle radials than distal radial cartilages and fin rays in the dorsal and anal fins. In G. wildenowi, the dorsal‐ and anal‐fin rays do not articulate with the distal tip of the proximal‐middle radials but are instead positioned between proximal‐middle radials, which is unusual for teleosts. Previously unrecognized dorsal and ventral pads of elastic hyaline‐cell cartilage are also present in the caudal skeleton of L. lepadogaster, G. wildenowi, and all other gobiesocids examined. J. Morphol., 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

16.
This is the report of a new species of catfish, Kryptoglanis shajii nov. gen. and nov. sp., distinguished from all other genera of siluriform fishes by the combination of the following morphological characters: viz. the absence of dorsal fin; the presence of four pairs of barbels; an upwardly directed mouth, with a distinctly projecting lower jaw; subcutaneous eyes; anal fin completely confluent with the caudal fin; anal and caudal fins together carry 70–74 fin rays; and no spines in any of the fins. Kryptoglanis, which has a maximum recorded size of 59.1 mm in standard length, was collected from a well fed by subterranean springs. The type locality is a well located at the extreme western part of Western Ghats, near Chalakudy in Thrissur district, Kerala State, India.  相似文献   

17.
In order to evaluate the effects of immersion marking with calcein (CAL) and alizarin red S (ARS) on growth and mortality of juvenile bighead carp Aristichthys nobilis, and assess mark quality in otoliths, scales, and fin rays, CAL from 50 to 200 mg L?1 and ARS from 150 to 300 mg L?1 concentrations were used. With the exception of non‐lateral line scales from 50 mg L?1 CAL treatments, immersion for 24 h produced detectable marks in sagittae, lateral line and non‐lateral line scales, and fin rays (dorsal, pectoral, ventral, anal, and caudal) at 100 days post‐marking. Detectable fluorescent marks in sagittae were readily observed at concentrations of 150–200 mg L?1 CAL or 150–300 mg L?1 ARS. Marks were poorly visible in all non‐lateral line scales from both CAL‐ and ARS‐treated groups. Fluorescent marks were readily detected in lateral line scales at 100–200 mg L?1 CAL or 150–300 mg L?1 ARS, and in fin rays at 150–200 mg L?1 CAL or 150–300 mg L?1 ARS. In particular, optimal marks were observed at the highest concentrations investigated in sagittae (300 mg L?1 ARS), lateral line scales (150–200 mg L?1 CAL or 250–300 mg L?1 ARS), and fin rays (200 mg L?1 CAL or 250–300 mg L?1 ARS). However, fluorescent marks visible to the naked eye were not produced by any of the CAL or ARS treatments in sagittae, scales, or fin rays during this experiment. In addition, there was no significant difference on survival and growth of marked fish compared to controls throughout the experiment (P > 0.05).  相似文献   

18.
Callionymus leucopoecilus, a new species of dragonet from the Yellow Sea, is described and illustrated. The new species is characterized by 4 spines in the first dorsal fin, 9 rays each in the second dorsal and anal fins, ii, 5, ii principal caudal fin rays, a preopercular spine formula of   相似文献   

19.
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.  相似文献   

20.
A new marine goby Callogobius sheni collected from coral reefs off southern Taiwan is described. The new species can be distinguished from congeneric species by the following combination of features: dorsal fin rays VI-I, 9; anal fin rays I, 7; pectoral fin rays 18; longitudinal scale rows 27–28; predorsal scale rows 9–10; no posterior oculoscapular and preopercular canals; body pale white with five blackish brown cross bands; caudal and pectoral fins each with a large blackish brown blotch.  相似文献   

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