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1.
Based on seven larvae from northern Australia, development ofCentrogenys vaigiensis—a species of uncertain phylogenetic affinities—is described for the first time. Identification was established from meristic
and osteological characters. Development is characterized by few morphological specializations and is apparently completed
at a small size (ca 5 mm standard length). Larvae are deep-bodied and compressed, with very limited head spination (small
spines on preopercle, subopercle, opercle and supracleithrum). Fin development takes place at about the time of notochord
flexion, and is complete at about 4.3 mm, with the exception of anal spine three, which does not fully transform from a soft
ray until after settlement. Fin spines are short, smooth and weak. Larvae are apparently limited to near-shore, shallow marine
waters, and based on the size of what are apparently settlement-stage larvae, the pelagic period may be short. 相似文献
2.
Larval and juvenile stages of kurosoi,Sebastes schlegeli, are described and illustrated from wild specimens. Some ecological aspects of larvae and juveniles are also described. Notochord
flexion occurred between 5.6–7.5 mm SL. Transformation occurred between 13–20 mm SL. Preflexion and flexion larvae ofS. schlegeli can be distinguished from similar larvae by the pigmentation of the dorsal and ventral midlines of the tail and absence of
pigmentation on the ventral portion of the rectum. After notochord flexion, the dorsal and lateral regions in both larvae
and pelagic juveniles were heavily pigmented, suggesting adaptation for neustonic life style. Larvae and juveniles were caught
at many coastal stations, but did not occur in cooler offshore waters. Larvae smaller than 20 mm SL inhabited surface waters.
Until ca. 40 mm SL, juveniles inhabited mainly surface waters (without drifting seaweed), but also used other habitats, such
as the drifting seaweed, and near the sea bed. Small larvae (<7 mm SL) fed mainly on copepod nauplii. Larger larvae fed on
calanoid copepodites andEvadne nordmanni. Pelagic juveniles fed mainly on fish eggs, with fish larvae also being important food items for some individuals. Most food
items taken by juveniles that were associated with drifting seaweed were eggs with attaching filaments (Cololabis saira andHyporhamphus sajori), suggesting that the high density of such food items both attracts and keeps juveniles around drifting seaweed. 相似文献
3.
Larvae of Asemichthys taylori were reared in the laboratory to identifiable juveniles. A preserved series of larvae was characterized in part by fin meristics
(X–XI, 14–15 dorsal fin rays; 15 anal fin rays), as well as a combination of the alignment of the jaw tip with the ventral
margin of the gut, heavy lateral melanistic pigment except on the caudal peduncle, and a series of postanal ventral melanophores.
An internal, horizontal band of melanin extends through the head from the snout to the gut. Hypural plates do not align vertically
even after settlement, giving the appearance that the larvae do not complete notochord flexion during their planktonic stage.
Larval A. taylori resemble known larvae of Radulinus spp., a genus under which some authors have synonymized the monotypic genus Asemichthys. 相似文献
4.
5.
Embryonic, larval and juvenile development of the roughskin sculpin,Trachidermus fasciatus (Scorpaeniformes: Cottidae) 总被引:1,自引:1,他引:0
Naohiko Takeshita Norio Onikura Seiichi Matsui Seirô Kimura 《Ichthyological Research》1997,44(2-3):257-266
Embryonic, larval and juvenile development of the catadromous roughskin sculpin,Trachidermus fasciatus, were described using eggs spawned in an aquarium. The eggs, measuring 1.98–2.21 mm in diameter, were light reddish-yellow
and had many oil globules, 0.05–0.18 mm in diameter. Hatching occurred 30 days after spawning at 2.3–11.3°C. The newly-hatched
larvae, measuring 6.9–7.3 mm BL, had a single oil globule, 9–10+25–26=34–36 myomeres and 6 or 7 large stellate melanophores
dorsally along the gut. The yolk was almost resorbed, number of pectoral-fin rays attained 16–17, and two parietal, one nuchal
and four preopercular spines were formed, 5 days after hatching, at 8.2–8.4 mm BL. The oil globule disappeared, and one supracleithral
spine was formed, 11 days after hatching, at 8.9–9.5 mm BL. Notochord flexion began 15 days after hatching, at 9.7–10.3 mm
BL. A posttemporal spine was formed 20 days after hatching, at 10.7–10.9 mm BL. The first dorsal fin spines (VII–VIII), second
dorsal fin and anal fin rays (18–19, 16–18, respectively) appeared 23 days after hatching, at 12.0–13.7 mm BL. The pelvic
fin spine and rays (I, 4) were formed and black bands on the head and sides of the body began to develop 27 days after hatching,
at 13.8–15.8 mm BL.
Newly-hatched larvae swam just below the surface in the aquaria. Preflexion larvae (8.9–9.5 mm BL), in which the oil globule
had disappeared, swam in the middle layer, while juveniles (13.8–15.8 mm BL) began swimming on the bottom of the aquaria.
Swimming behavior observed in the aquaria suggested that the fish started to change to a demersal existence at the juvenile
stage. 相似文献
6.
Larvae and juveniles of the alepocephalid fishes, Leptoderma lubricum [26.9–69.0 mm in standard length (SL)] and Leptoderma retropinnum (21.1–67.2 mm SL), collected within 1–8 m of the seafloor in Suruga Bay, southern Japan, are described. They can be easily
distinguished from each other by the following adult-like characters: membrane morphology between the vertical fin rays and
procurrent caudal-fin rays (separated in L. lubricum vs. continuous in L. retropinnum), numbers of dorsal-fin rays (34–40 vs. 45–52) and anal-fin rays (50–57 vs. 65–72), and caudal peduncle length (11.7–13.4%
SL vs. 4.5–5.9% SL), in addition to several other body proportional differences. Unique characters in the larval stages of
Leptoderma include a translucent occipital region, horizontally elongated eye, and head below the upper margin of the orbit and abdominal
cavity densely covered by melanophores, ontogeny being characterized by the acquisition of general adult characters to the
postflexion stage, indistinct transformation, and the retention of few larval characters until almost the end of the juvenile
stage, as in other known alepocephalids. In addition to the near-bottom larval and juvenile collections of both species, the
occurrences of benthic or near-bottom taxa, including Harpacticoida, in their gut contents confirmed the early life history
dependence of the former on the near-bottom. 相似文献
7.
Makoto Okamoto Yutaka Kurita Hiroya Sugisaki Takashi Asahida 《Ichthyological Research》2010,57(4):398-405
Larvae of bigmouth manefish Caristius macropus are described and illustrated on the basis of seven specimens (4.2–10.5 mm in body length) from the Kuroshio waters (0–60 m
depth) and the transition waters (surface) between the Kuroshio and Oyashio fronts of the western North Pacific. The present
larvae of C. macropus are distinguished from those of Paracaristius maderensis that inhabit the North Pacific by having 39–40 myomeres, 34 dorsal-fin rays, and 22 anal-fin rays. The present study, along
with previous studies of the early life stages of caristiids, shows that larvae of the family may be defined by the following
characters: body elongate in preflexion stage but becoming deep bodied and hatchet shaped after notochord flexion; anus located
near vertical through base of pectoral fin; head large, without spination or serration; a distinct vertical band on the posterior
tail throughout the larval stages, and two bands gradually appearing on the tail and trunk during the flexion and postflexion
stages; and melanophores present around the notochord tip by the flexion stage. Adult C. macropus are found in the subarctic and temperate waters of the North Pacific; however, the present study and other occurrences of
early life stages of the species probably indicate that C. macropus may spawn over a wide area in the North Pacific. 相似文献
8.
Larvae of two paralichthyids, Pseudorhombus oculocirris and P. arsius, are described and illustrated from specimens collected off Tosa Bay, southern Japan. Peudorhombus oculocirris larvae (5 specimens, 4.5–7.8 mm BL) are characteristic in having 6 or 7 elongated anterior dorsal fin rays and poorly developed
head spines and melanophores on the tail. Pseudorhombus arsius larvae (3 specimens, 5.3–8.4 mm BL) are distinctive in having 11 or 12 elongated anterior dorsal fin rays and well-developed
head spines, including a row of spines on the sphenotic.
Received: June 28, 2001 / Revised: November 2, 2001 / Accepted: November 22, 2001 相似文献
9.
Rainfordia opercularis was described in 1923 from a single specimen taken in Edgecumbe Bay, Queensland, Australia. The species is rare in museum
collections, and the larvae have not been described. In 1999, two settlement-stage larvae (20–21 mm in standard length) were
collected in light traps set off Lizard Island, Great Barrier Reef, Queensland. The smaller of the two has one thin, flexible,
extremely elongate dorsal-fin spine encased in a pigmented sheath. The larger specimen lacks an elongate dorsal-fin spine
and exhibits caudal-fin pigment characteristic of adults. A combination of features in one or both of the settlement-stage
larvae support the placement of Rainfordia in the epinepheline-serranid tribe Liopropomini: presence of an elongate, filamentous dorsal-fin spine serially associated
with the first dorsal-fin pterygiophore; presence of a spine on the inner preopercular ridge; presence of dense pigment on
the frontals; absence of an elongate spine at the angle of the preopercle; and absence of supraorbital spination.
Supplementary material to this paper is available in electronic format at 相似文献
10.
The early life history of Ayu (Plecoglossus altivelis) was investigated in the Kalong and Tien Yen River systems, northern Vietnam, which is probably the most southern distribution
locality for this species, during the period of November 2010 to February 2011. A total of 248 larvae were captured in the
Kalong, and none were collected in the Tien Yen. There was little difference in development between the Kalong larvae and
those of P. a. altivelis and P. a. ryukyuensis. Temperatures and salinities when the larvae were collected ranged from ca. 12 to 21°C and from ca. 3.5 to 30 psu. The preflexion
to flexion larvae (primarily preflexion with yolk, 5.2–12.9 mm BL) occurred in the central current from December to February,
with a peak abundance in early January. The flexion to postflexion (primarily postflexion, 14.1–23.8 mm BL) larvae occurred
in the bank waters from early January to late February. The larval occurrence in the Kalong was 1–2 months later than for
P. a. altivelis in Japan and P. a. ryukyuensis in the Ryukyu Islands, probably because of the delay until a reasonable photoperiod for the start of spawning in the lower
latitudinal region. The larvae were never collected from the sea, where the temperatures were lower than in the river and
estuary in January and February, unlike in Japan. 相似文献
11.
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
12.
Larval development of Leiognathus equulus is described from reared postflexion specimens (4.6–15.8 mm Standard Length, SL) from Taiwan. Larvae have strong head spination,
particularly a supraoccipital crest, strong supraocular ridge and very long, serrate preopercular spines, with the spine at
the preopercular angle initially heavily pigmented. Fin spines are robust, and the anterior spines of dorsal, anal and pelvic
fins are long and serrate. Structures characteristic of the family Leiognathidae form early in development (ca. 5 mm SL),
including the very protrusible mouth, the fin-locking mechanism and the bacterial light organ. Pigment is initially largely
confined to the ventral midline, but as development proceeds, extensive lateral and dorsal pigment patches appear. Larvae
of L. equulus have the Trnski and Leis Morph 1 morphology. 相似文献
13.
Pelagic larvae of two pleuronectiforms, Poecilopsetta plinthus (Poecilopsettidae) and Parabothus coarctatus (Bothidae), are described and illustrated based on specimens collected off Tosa Bay, southern Japan. Postflexion larvae (8.2–11.9
mm BL) of Poecilopsetta plinthus are characteristic in having a series of melanophore patches along the dorsal and anal fin bases and the inner margins of
the pterygiophore zones, and linear myoseptal pigmentation also along the inner margins of the latter. Preflexion and flexion
larvae (5.0–6.3 mm BL) of Parabothus coarctatus are distinctive in having the dorsal fin origin located level with the dorsal margin of the eye and seven elongated rays
in the anterior part of that fin.
Received: November 18, 2000 / Revised: May 1, 2001 / Accepted: June 13, 2001 相似文献
14.
The embryonic, larval and juvenile development of blue whiting,Sillago parvisquamis Gill, are described from a series of laboratory-reared specimens. Mean egg diameter and mean total length (TL) of newly-hatched
larvae were 0.71 mm and 1.58 mm, respectively. The eggs were non-adhesive, buoyant and spherical with an oil globule (mean
diameter 0.18 mm). Hatching occurred about 20 hours after fertilization at a temperature of 24.0–25.0°C, newly-hatched larvae
having 38–40 myomeres. The yolk and oil globule were completely absorbed 3 days after hatching at 2.8–3.2 (mean 3.0) mm TL.
Notochord flexion was completed by 7.2–8.2 (7.7) mm TL, and pectoral and caudal fin rays fully developed by approximately
10 mm and 8.5 mm TL, respectively. Completion of fin development occurred in the following sequence: caudal, pectoral, anal
and second dorsal, first dorsal and pelvic, the last-mentioned by approximately 11 mm TL. The larvae ofS. parvisquamis andS. japonica, which closely resemble each other in general morphology and pigmentation, could be distinguished as follows. Newly-hatchedS. parvisquamis larvae had more myomeres thanS. japonica (38–40 vs. 32–34) and more melanophores on the dorsal surface of the body (19–28 vs. about 40).Sillago japonica had a vertical band of melanophores on the caudal peduncle, which was lacking in postflexionS. parvisquamis larvae. In addition, juveniles ofS. parvisquamis (larger than 23 mm TL) had melanophores on the body extending anteriorly to below the lateral line to form a midlateral band,
whereas no obvious band occurred on similarly-sizedS. japonica juveniles. 相似文献
15.
Two larvae [17.4 mm standard length: SL (postflexion stage)] and 26.1 mm SL (transformation stage)] and a juvenile (31.7 mm
SL) of a phosichthyid, Polymetme elongata, from Suruga Bay and offshore waters, central Japan, are described. These specimens had an elongate body with relatively
short preanal length (53–63% SL), long anal fin base (2.6–3.4 times dorsal fin base length), and anal fin origin below dorsal
fin base, and were further characterized by a blackish flap on each eye and internal clusters of melanophores (e.g., along
caudal myosepta around midlateral line and on ventral margin of caudal peduncle). The short preanal length and larval melanophore
pattern were very similar to those of another phosichthyid, Yarrella blackfordi, from the Atlantic Ocean. 相似文献
16.
Larvae and juveniles of Alectis indica reared in captivity are described based on 47 specimens (3.2–32.0 mm in body length: BL). Development was typical for the tribe Carangini except for the presence of elongated fin filaments. Elongated dorsal-fin filaments were present at preflexion (3.2 mm BL). During flexion, the anal- and pelvic-fin rays elongated and the body deepened. The full complement of fin spines and rays was present by 7.1 mm BL. The larvae of A. indica could be differentiated from those of Alectis ciliaris, which also inhabits in the Indo-Pacific waters, by the presence of a ventral series of melanophores on the tail, elongated pelvic fins, and the timing of anal-fin spine migration. The rounded body and elongated fin rays of A. indica cause it to resemble venomous Cubomedusae. 相似文献
17.
A new snailfish, Careproctus notosaikaiensis, is described on the basis of 6 specimens collected from the central part of the Sea of Japan, off Saikai, western coast
of the Noto Peninsula, Ishikawa, Japan. The new species is distinguished from other congeners by the following combination
of the characters: vertebrae 57–58, 10–12 abdominal and 46–48 caudal; dorsal-fin rays 52; anal-fin rays 46–47; principal caudal-fin
rays 10; pectoral-fin rays 35–37; pectoral fin with a deep notch; proximal pectoral radials 4 (3 + 1), round; gill slit extending
to pectoral-fin ray 4–7; teeth strongly trilobed; pleural ribs 2 pairs; 2 suprabranchial pores; chin pores paired in the same
pit; pyloric caeca 20–29; dorsal and anal fins with dark margins and stomach black in preserved specimens. 相似文献
18.
Early ontogeny of the big roughy Gephyroberyx japonicus (Beryciformes: Trachichthyidae) in captivity
Development of eggs and larvae of the big roughy Gephyroberyx japonicus are described on the basis of specimens reared in captivity. Spherical eggs (diameter 1.26–1.35?mm) with a single oil globule were pelagic. Newly hatched larvae (2.8–3.1?mm in body length, BL) had strong linear pigmentation on the head and trunk. The mouth opened at ca. 3.5?mm BL; thereafter the yolk was absorbed. Notochord flexion started at ca. 4.5?mm BL when body depth increased rapidly, and melanophores spread to all of the body. Notochord flexion was completed at ca. 5.0?mm BL. Head spination and pelvic fins began to develop during the flexion stage. 相似文献
19.
The early development of the endangered freshwater goby, Rhinogobius sp. BI (ogasawara-yoshinobori in Japanese), was described in the course of a serial rearing experiment over generations as
ex situ preservation. The eggs, measuring 2.0 mm in long diameter and 0.7 mm in short diameter, were elliptical with a colorless
transparent chorion, a slightly yellowish yolk, and some oil globules. Hatching occurred naturally at 6 to 7 days after spawning
at 24.0°C. Newly hatched larvae, measuring 3.2–3.4 mm in total length (TL), had opened mouth and a globular yolk sac. The
yolk was completely absorbed at 3.5 mm TL (5 days after hatching). Notochord flexion initiated at 5.7 mm TL (18 days) and
finished at <9.1 mm TL (30 days). First dorsal fin began to form in postflexion larvae at 10.0 mm TL (40 days), and a full
complement was attained at 11.6 mm TL (45 days). Second dorsal fin emerged at 5.7 mm TL (18 days); full count was attained
and segmentation initiated at 9.1 mm TL (30 days). Anal fin anlage appeared at 5.7 mm TL (18 days); its ray count was completed
and segmentation initiated at 9.1 mm TL (30 days), and branching at 15.6 mm TL (60 days). Caudal fin support appeared at 4.5 mm TL
(15 days); segmentation initiated at 6.0 mm TL (24 days) and branching at 10.0 mm TL (40 days). Fanlike pectoral fin present
in newly hatched larvae. Pectoral fin rays appeared at 10.0 mm TL (40 days), and its ray count completed at 15.6 mm TL (60
days). Pelvic fin projected at 9.1 mm TL (30 days), and a sucking disc partially formed at 11.6 mm TL (45 days). Aggregate
numbers of all fin rays were completed at 15.6 mm TL in 60 days after hatching. Pelagic period continued for about 40 days,
and settlement was completed in postflexion larvae at 45 days. 相似文献
20.
The early life history and development of the scopelarchid Benthalbella linguidens was studied, based on 203 specimens (from 5.3 to 89.7mm in body length: BL) collected from Kuroshio, Oyashio waters and transition waters of the western North Pacific. The early life stages of B. linguidens are distinguished from those of other species of Benthalbella that inhabit the North Pacific by the characters of 62–64 myomeres in the larval stage and 26–28 anal fin rays in juvenile and transforming specimen. Larvae are elongate; notochord flexion begins at ca. 12mm BL and is completed at ca. 15mm BL. The fin ray complements are established at ca. 40mm BL. The single transforming specimen (89.7mm BL) that has peritoneal pigment was collected from transition waters. All larvae were collected from Kuroshio and transition waters from winter to early summer; however, the size of larvae in Kuroshio waters was apparently smaller than that in transition waters, with ranges of 5.3–32.4mm BL (mean 17.1) and 15.3–35.3mm BL (mean 27.5), respectively. Juveniles were distributed in transition and Oyashio waters and were absent in Kuroshio waters, where adults are commonly distributed. These occurrences of larvae and juveniles in the western North Pacific indicate that B. linguidens spawns in Kuroshio waters in winter and uses transition waters as nursery grounds. 相似文献