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1.
Two new species of bucephalid trematodes are described from the rectum and intestine of the western moray eel Gymnothorax woodwardi McCulloch (Anguilliformes: Muraenidae: Muraeninae) off Point Peron in Western Australia. Dollfustrema gibsoni n. sp. is distinguished by body size, a pharynx that is intertesticular and level (latero-dextrally) with the anterior portion of the cirrus-sac, an ovary positioned dextrally to the testes and slightly anterior to (in part) the anterior testis, a uterus that extends anteriorly to the vitelline follicles but not to the level of the rhynchus, and vitelline follicles that form a confluent arc anterior to the gonads. Muraenicola nom. nov. is proposed as a replacement generic name for the pre-occupied Folliculovarium Gu & Shen 1983 nec Singh & Sinha 1981. Muraenicola botti n. sp. is distinguished from its congeners by body size, the size of the cirrus-sac (relative to body size), and in possessing tegumental spines, testes that are oblique (rather than in tandem) and eight ovarian lobes. It differs further in having an intestinal caecum that extends anteriorly to the level of the vitelline follicles and in the position of the pharynx and cirrus-sac relative to each other (lateral in part) as well as to the gonads. M. botti n. sp. also lacks a metraterm. These are the first reports of these genera from fishes off Australia and from the southern hemisphere.  相似文献   

2.
Monostephanostomum georgianum n. sp. is described from Arripis georgianus off Kangaroo Island, South Australia. It differs from its congeners by the presence of a short second row of oral spines. M. manteri Kruse, 1979 is reported from A. georgianus off southern Western Australia and Kangaroo Island, South Australia and A. trutta off northern Tasmania. It is considered that the other two species, M. yamagutii Ramadan, 1984 and M. krusei Reimer, 1983, should probably be removed from this genus. Two new combinations are formed, M. gazzae (Shen, 1990) n. comb. (from Stephanostomum) and M. mesospinosum (Madhavi, 1976) n. comb. (from Stephanostomum). A key to the four recognised species of Monostephanostomum is given.  相似文献   

3.
Pseudodiplectanum syrticum n. sp. (Monogenea: Diplectanidae) is described from the gills of Synapturichthys kleinii (Risso) collected from the Gulf of Gabès in the Mediterranean Sea off Tunisia. The new species differs from the congeneric species by the morphology of the penis and vagina. It resembles the Mediterranean species P. kearni Vala, Lopez-Roman & Boudaoud, 1980 from Solea vulgaris Quensel and P. gibsoni Oliver, 1987 from Michrochirus variegatus (Donovan) in its tubular penis, but it differs from these two species by having a vagina with a long tube presenting two loops and a male copulatory organ ending in a curved point. It also differs in the morphology and size of the transverse bars of the haptor. In P. syrticum the ventral transverse bar and dorso-lateral bars are longer than those of P. gibsoni (114 vs 69.5-89 microm and 48 vs 33-44 microm, respectively).  相似文献   

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6.
The northern portion of the geographic range of the American eel Anguilla rostrata may contribute a great proportion of the reproductive potential to this panmictic species because of apparent increases in average female size and female percentage with latitude. The regressions of fecundity on body length and on body weight of 63 female eels captured at about 45° N latitude on their spawning migration to the sea were log F= 1·2601 + 2·9642 log L and log F= 4·1646+0·9153 log W , where F is fecundity, L is total length (cm), and W is total weight (g). Length and weight each explained about 90% of the variation in fecundity. Estimates of fecundity from counts of aliquots of eggs ranged from 1·84 million to 19·92 million eggs for eels ranging in length from 45 to 113 cm, nearly the range of sizes of migrating females reported in the literature. Fecundities of the American eel were greater than reported in one study at about 37° N and greater than reported for the European eel, A. anguilla , shortfin eel, A. australis , and longfin eel, A. dieffenbachii . If a geographic cline in fecundity does exist in American eels, it is established anew each generation because the species forms a single panmictic population.  相似文献   

7.
Adlardia novaecaledoniae n. g., n. sp. (Digenea: Cryptogonimidae) is described from the fish Nemipterus furcosus (Val.) (Perciformes: Nemipteridae) from off New Caledonia (South Pacific). Adlardia n. g. is distinguished from all other cryptogonimid genera by the combination of an elongate body, the presence of oral spines, intestinal caeca that open via ani at the posterior end of the body, a highly lobed ovary, oblique testes that are located in the mid-hindbody, vitelline follicles that extend from midway between the testes and ovary to midway between the ovary and ventral sucker, and an excretory vesicle that bifurcates dorsal to the ovary and reunites immediately anterior to the pharynx. A. novaecaledoniae n. sp. is the only cryptogonimid that has been reported with an excretory vesicle that reunites anterior to the pharynx. Siphoderina elongata (Gu &; Shen, 1979) Miller &; Cribb, 2008 is transferred to Adlardia as A. elongata (Gu &; Shen, 1979) n. comb. based on morphological and ecological (host group) agreement with A. novaecaledoniae. Bayesian inference analysis of LSU rDNA revealed that A. novaecaledoniae nested well within a clade containing cryptogonimid taxa known almost exclusively from haemulid and lutjanid fishes, suggesting that host-switching between teleosts of the Haemuloidea, Lutjanoidea and Sparoidea may have been common in the evolutionary history of this system.  相似文献   

8.
The capture of a specimen of Laemonema latifrom Holt & Byrne, 1908, off Blanes (western Mediterranean) at a depth of 550m, in December 1983, is reported for the first time in this region.  相似文献   

9.
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   

10.
Karaytug S  Sak S  Alper A 《ZooKeys》2010,(53):1-12
Male and female of Odaginiceps korykosensis sp. n. (Copepoda, Harpacticoida, Tetragonicipitidae), collected in the intertidal zone of Kızkalesi beach along the Mediterranean coast of Turkey (Mersin Province), are described. The new species is the fifth member of the genus and can easily be distinguished from the other species by the presence of four setae/spines on the second endopodal segment of P4 and by the structure of the caudal rami. Previously, representatives of the genus Odaginiceps have been reported from Gulf of Mexico, off Bermuda and Kenya. Odaginiceps korykosensis sp. n. is the first record of the genus in the Mediterranean Sea.  相似文献   

11.
Sundapolystoma chalconotae. n. g., n. sp. (Polystomatidae, Polystomatinae) is proposed for a new polystomatid from the urinary bladder of Rana chalconota (Schlegel) in Peninsular Malaysia. This is the first species of polystomatid to be described from the amphibians of Peninsular Malaysia and the second for the Southeast Asian region. This new genus, as exemplified by S. chalconotae, differs from other polystomatids, and in particular Parapolystoma Ozaki, 1935 (P. bulliense (Johnston, 1912) Ozaki, 1935 and P. johnstoni Pichelin, 1995), in having a tubular uterus and a single diffuse testis. P. crooki Vande Vusse, 1976 is similar to S. chalconotae in having a similar type of uterus and testis, and is re-assigned as Sundapolystoma crooki (Vande Vusse, 1976) n. comb. S. chalconotae differs from S. crooki in having anchors with a longer outer root rather than a longer inner root and 7-8 genital spines compared to 9-13 in S. crooki.  相似文献   

12.
记述中国奇刺(虫兆)属具有6臀刺的1新种,卜氏奇刺姚Friesea buyuni sp.nov..文中给出奇刺(虫兆)属中具有2+2小眼种类的检索表;并给出丽江奇刺(虫兆)的新发布记录.模式标本保存在上海昆虫博物馆.  相似文献   

13.
Bradya typica Boeck, 1873 is described from samples collected in the course of a colonisation experiment in Kongsfjorden, Spitsbergen (2003–2005). The male of B. typica, the type-species of the genus is described for the first time. B. typica can be distinguished from its congeners by its caudal rami (1.4 times longer than wide) and by its P5 (exopod longer than wide, inner terminal seta of exopod longest, inner seta of baseoendopod longer than outer one and surface seta rigid and curved). Variability within the species is rather small as only the length of some setae is slightly different. B. cladiofera Lang, 1965, B. congenera Sars, 1920, B. minutiseta Soyer, 1973 and B. pugiochaeta Arlt, 1983 are closely related to B. typica. Some details of the morphology, such as the body ornamentation and the longer hair-like pinnules on the spines of the swimming legs, are very difficult to observe even with maximum magnification. With certainty, B. typica is distributed near the Norwegian coast (Oslo Fjord to Trondheim Fjord), the Swedish coast (Skagerak to Öresund), around Spitsbergen and around the polar islands north of Grinnelland (Canadian Arctic Archipelago near Baffin Bay). Records of B. typica from the Kara Sea (near Novaya Zemlya), near Franz Joseph Land, Iceland, Greenland, the British Isles and from deep waters of the North Sea have to be confirmed.  相似文献   

14.
Morphological features that impair a predator's ability to consume a prey item may benefit individual prey; but what of features that prolong prey-handling but do not enhance prey survival? For example, a striped eel catfish Plotosus lineatus will be fatally envenomated if struck by its specialist predator, the greater sea snake Hydrophis major. Nonetheless, the catfish typically erects long, toxic pectoral and dorsal spines that increase prey-handling times for the snake by around eightfold. Because the catfish travel in swarms of closely-related individuals, the delay enforced by spines may enable the victim's swarm-mates to disperse before the snake is able to search for another meal. In keeping with that hypothesis, defensive spines tend to be longer in catfish from regions where the greater sea snake occurs, than from areas where the snake does not occur.  相似文献   

15.
Stephanostomum kovalevae Parukhin, 1968 from the intestine of Lophius vomerinus off Swakopmund, Namibia, is redescribed. It is characterised by its large number (c. 73-88) of circum-oral spines, its relatively very long hindbody and the vitellarium reaching close to or just overlapping the ventral sucker. S. beukelaardori n. sp., from the intestine of Zenopsis conchifera off Walvis Bay, Namibia, is described. It belongs to the group of species where the vitellarium reaches the ventral sucker, and which has c. 32-38 circum-oral spines. It is closest to S. casum (Linton, 1910), but differs in lacking the lining of prominent spines in the ejaculatory duct, probably in egg-size and in both forebody and hindbody lengths.  相似文献   

16.
A new species belonging to a new genus of Monogenoidea was found on the gills of Euleptorhamphus viridis from the Indian Ocean. The opisthohaptor of the new genus consists of two medially overlapping rows of clamps situated on a double fold along the oblique posterior margin of the body. Clamp are of Microcotyle type, their springs having accessory pieces. Three pairs of larval hooks are present. The genital atrium is armed with three groups of spines. The first group comprises spines surrounding the female aperture; the second one surrounds the cirrus in an incomplete circle; the third group consists of two lateral groups of spines arising from two muscular pad-like structures. Vagina armed with a chitionous spine opens on the right-hand side which is longer than the left-hand one. Behind the U-shaped ovarium vitellaria merge in an undifferentiated mass and completely cover the branches of the intestine and the testes. The new genus is close to the genera Chlamydaxine Unnithan, 1957 and Axine Abildgaard, 1794 differing from the former by an armed genital atrium and from the latter by two medially overlapping rows of clamps.  相似文献   

17.
 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   

18.
Plagiocirrus loboides n. sp. (Digenea: Opecoelidae) is described from Fundulus nottii, F. dispar blairae, F. chrysotus, and Notemigonus crysoleucas from the Pascagoula River in Mississippi. Plagiocirrus loboides differs from P. primus Van Cleave and Mueller, 1932, by having a longer postcecal space (14-25% of body length vs. about 7%); a more anterior vitellarium (extending at least to the middle of the ventral sucker vs. to its posterior margin); and larger eggs (51-71 microm long by 23-34 microm wide vs. 40-55 microm long by 30-35 microm wide). Plagiocirrus loboides differs from P. testeus Fritts, 1959, by having a long postcecal space (vs. < 5% of body length); irregular, oblique, contiguous testes (vs. strongly lobed, well separated, tandem testes); and a more extensive vitellarium. Plagiocirrus loboides differs from both congeners by having an ovary comprised of 3 or 4 distinct lobes rather than having an entire ovary. Plagiocirrus wuyienensis Wang, 1981, from Hemimyzon zebroidus in Fujian Province, China, is herein considered a species inquirenda because it has a Y-shaped excretory bladder. Molecular phylogenetic analysis of 28S rDNA gene fragments from P. loboides and 17 digenean species demonstrates that Plagiocirrus belongs in Opecoelidae.  相似文献   

19.
Gerres infasciatus sp. nov. is described from the holotype and two paratypes, 125–140 mm in standard length (SL), collected off Samut Prakan, northern Gulf of Thailand. The species is similar toG. filamentosus Cuvier andG. macracanthus Bleeker in general appearance, having an elongated second dorsal fin spine, but differs from them in having 39 or 40 pored lateral line scales, the first and second soft dorsal fin ray tips yellow in fresh specimens, a narrow, faint dusky-yellowish margin on the upper membrane of the spinous dorsal fin (between 4th–9th spines), the distal part of the pelvic fin (between 1st–5th soft rays) white for 1/3–1/2 of each ray length (lost after preservation), bands absent on the body in both fresh and preserved specimens, a smaller orbit diameter (11.4–12.4% of SL), a longer second dorsal fin spine (48.0–68.9% of SL), and shorter second and third anal fin spines (10.7–11.2% and 10.4–11.3% of SL), respectively.  相似文献   

20.
Synopsis The number of venomous caudal spines and their length and position relative to one another were determined in seven species of South American freshwater rays (Potamotrygonidae) and eight marine or euryhaline species of four families from the Caribbean Coast of South and Central America. Most species have two visible spines at certain stages in the shedding-replacement cycle and only one visible spine at other stages (following shedding). If we include the embryological beginnings of the spines before they erupt and become visible, the spine counts of most rays are actually 2 rather than 1 or 2. Since most species apparently follow this pattern, spine counts are of little use in distinguishing between species except in the relatively few that may have only one, or no spines. Eight captive Potamotrygon specimens maintained in simulated tropical temperature conditions over 12 months showed periodic shedding and replacement of spines. The molts were biannual for a given ray but annual for a given spine. They alternated between two spine loci and their cycles were approximately six months out of phase with each other. Recent studies on Dasyatis sabina by others report only one molt per year, with replacement spines forming always posterior to the primary spine rather than alternating between posterior and anterior. Supernumerary spines (counts of more than two, up to five) are also discussed, as are counts of one and zero.  相似文献   

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