Does the river blenny Salaria fluviatilis (Asso, 1801) (Actinopterygii: Perciformes) still survive on the Mediterranean island of Cyprus?

The river blenny (Salaria fluviatilis) is rarely mentioned in the natural history literature of Cyprus. This has led to doubts about its existence there. Mistakes with mismatched fish collections have occurred in the past, so it is worth asking whether the recorded specimens are actually from Cyprus and whether the species survives there today. Archived correspondence from the original specimen collector confirms that the record of S. fluviatilis on Cyprus is genuine, yet our extensive surveys there during the last 4 years have failed to locate the fish. A review of the species’ Mediterranean island distribution shows that it exists on 10 islands that are either close to the mainland or are relatively very large in areal extent. Although the mystery of S. fluviatilis survival on Cyprus lingers, efforts must be made to survey all potential habitats and consider planning a re-introduction project if the population is confirmed as extinct.     

Wolves in sheep’s clothing: three new cases of aggressive mimicry in Red Sea coral reef fishes

ABSTRACT

Here we document three cases of mimicry in coral reef fishes not previously reported in the literature involving two groupers (Epinephelus leucogrammicus and Plectropomus marisrubri) and a soapfish (Diploprion drachi) as mimics, and two wrasses (Larabicus quadrilineatus and Cheilinus quinquecinctus) and a blenny (Meiacanthus nigrolineatus) as models. All three cases are of aggressive mimicry, with a predatory species mimicking a harmless one, and in one of the cases, the mimicry is also Müllerian, where both the predator and harmless species are unpalatable.     

Natural diet of fish and crabs associated with the phytal community of Sargassum cymosum C. Agardh, 1820 (Phaeophyta,Fucales) at Ponta das Garoupas,Bombinhas, Santa Catarina State,Brazil

The diet of fish and crabs associated with Sargassum cymosum beds was analysed at Ponta das Garoupas, Santa Catarina State, southern Brazil. They are reported to feed on phytal organisms. The relative importance of food items was established for these consumers, and the frequency of occurrence and volumetric methods were used for quantitative analysis. The analysis of 272 guts from 11 fish and two decapod species revealed that eight fish and one crab species had phytal organisms as important items in their diet. Amphipods and molluscs were the main phytal animals in the diet of these fish and the crab; notably Caprella scaura, Hyale media, Atylus minikoi, Tricolia affinis and Bittium varium. Commercially important fish, such as the grouper Epinephelus guaza, feed on these fish and crabs, showing that Sargassum beds constitute an important link between benthic autotrophic producers and several levels of consumers on rocky shore ecosystems at Ponta das Garoupas.     

Home-range fidelity and use of historic habitat by adult Colorado pikeminnow ( Ptychocheilus lucius ) in the White River, Colorado and Utah

Twelve wild adult Colorado pikeminnow ( Ptychocheilus lucius ), captured in the tailwaters of Taylor Draw Dam on the White River, Colorado, were implanted with radio transmitters and their movement patterns monitored from 1992 to 1994. The spawning migration of these fish was extensive. In 1993, the only full year of the study, the fish migrated an average of 658 km from the White River to spawning sites in the Yampa or Green rivers and back to the White River. Eight of these fish were translocated in the river upstream of the dam in April 1993. These fish and the 4 others below the dam remained in the river until May 1993. All 12 had migrated down the White River to spawning sites in the Green and Yampa rivers by July 1993. The fish that were located above the dam successfully passed over the dam during their downstream migration. Seven fish migrated upstream toward the Yampa River Canyon spawning site and 5 migrated downstream toward the Green River Desolation/Gray Canyon spawning site. Five of 7 Yampa River fish were found at the spawning site. The other 2 were found 5-8 km downstream of the site. One of 5 Green River fish was found at the spawning site, the other 4 between 16 and 62 km upstream of the site. All fish migrated back to the White River by August 1993 and were found near the dam by October 1993. Two fish were recaptured and translocated above the dam in September 1993. Five fish were located below the dam and 2 above the dam in April 1994. By July 1994 seven of the same fish that had migrated toward the Yampa River in 1993 were found at the Yampa Canyon spawning site. At the same time, 3 of 5 fish that migrated toward the Green River in 1993 were found at the Desolation/Gray Canyon spawning site. This included 2 fish that had been found upstream of the site in 1993. The 12 fish traveled an average of 6 km d -1 (range: 4-10 km d -1 ) during the migration period from May through October 1993. Generally, fish moved faster to the spawning site than back from the site to the White River. These fish moved very little within their home ranges in the White River. Six fish tagged in 1992 moved only 0.1-2.3 km in the tailwater reach below Taylor Draw Dam from September 1992 through April 1993. All fish, after their spawning runs, had moved up to or near the dam by October 1993. These fish were not tracked again until April 1994. Their movement patterns in April 1994 were similar to those observed in April 1993. The greatest amount of fish movement in the White River was displayed by the 8 fish placed above Taylor Draw Dam in April 1993 and the 2 placed in Kenney Reservoir in September 1993. They moved 1.1-40.6 km in the river before and after their spawning migration in spring and autumn 1993. These spawning migrations suggest that adult Colorado pikeminnow in the White River were recruited from both Green and Yampa river spawning populations and were presumably imprinted to these respective spawning sites. Those fish placed above Taylor Draw Dam established home ranges in habitats previously occupied by Colorado pikeminnow before the dam was completed. They remained there until they migrated downstream during the spawning period. Although we did not study fish passage, our study demonstrates that adult Colorado pikeminnow will use habitat if access is provided. Translocation of wild adult fish into historic but unoccupied habitats may be a valuable recovery option.     

Tadpole deposition behaviour in male stream frogs Mannophryne trinitatis (Anura: Dendrobatidae)

Male Mannophryne trinitatis transport their larvae on their backs to predator‐free pools and deposit them there. The experiments reported here investigated M. trinitatis male deposition behaviour in containers placed near a heavily fish‐populated stream at Mount Saint Benedict, northern Trinidad. Choice of deposition site was not related to height above or distance from the stream. The low mean number of tadpoles deposited in each container in the field and in a laboratory experiment indicated that most males tended not to deposit complete clutches in single pools. Deposition experiments in the laboratory with a choice of different‐sized containers showed that deposition was pool size dependent, with more tadpoles deposited in larger containers. Deposition behaviour when given a choice of containers with leaf litter (a source of food and shelter) and with no leaf litter showed no significant preference. Tadpoles grown in different water volumes with different food sources revealed that tadpole growth was best in larger water volumes containing leaf litter. Regular tadpole inspections at a pool in the field established that most tadpoles present were the result of downstream movement.     

II.—Association between sessile colonial hydroids and fishes

Résumé

1. 1. There is a symbiosis between Sertularia operculata and Squalus acanthias, and between Seralia lendigera and Hippocampus ramulosus—there being but a single case reported for each pair of organisms. It is probable that these associations are entirely accidental.

2. 2. Of Stylactis minoi and Minous inermis, no fewer than twenty-nine specimens of the fish (presumably all ever taken) wherever found—and they have been taken from five widely distant stations on both coasts of India, and from Japan—were infested with the hydroid. Furthermore, so far as known, this particular hydroid has never been found save on this particular fish (inermis). These facts would seem to indicate that this is a purposive or obligate symbiosis.

3. 3. About one hundred specimens of Hypsagonus quadricornis were taken in Puget Sound. Thirty-seven of these were preserved, and ten of them were found to be sparsely covered with Perigonimus pugetensis. Other specimens of the fish taken outside Puget Sound and in Behring Sea all lacked the hydroid. Consideration of all these facts leads to the conclusion that the association is symbiotic and more or less accidental.

4. 4. One case has been presented of Hydrichthys mirus attached to Seriola zonata in Narragansett Bay. Parasitism is alleged, but the proofs offered, that there was some apparent degeneration on the part of the hydroid and some slight evidence of wasting away of the muscles of the fish at the point of attachment, are at best inconclusive, there being no evidence from sections presented to show actual anastomosis of the tissues of the two organisms. From the evidence presented one must conclude that this is only a case of symbiosis.

5. 5. One case is known of the attachment of a Nudiclava to a fish, Monacanthus, from the Andaman Sea. Parasitism is alleged in the title of the paper, but disclaimed in the text, since, in sections cut through the basal plate and the skin to which it was attached, such was not proven. Furthermore, the finding of food in the hydranths discounts the idea of parasitism. This case also must be classed as a symbiosis.

6. 6. True parasitism has been repeatedly shown to exist between an aberrant hydroid, Polypodium hydriforme, and the ovarian eggs of the Volga sterlet, Acipenser ruthenus. This has been definitely established by the work of four investigators, extending in time from 1872 to 1922—a half century. Except in its earliest stages, Polypodium has the nutritive cell-layer of its stolon, the endoderm, on the outside bathed in the egg-yolk. Later this becomes inverted and a large amount of yolk is carried into the common cavity. The egg is used up in nourishing the parasite.

7. 7. True parasitism has been shown between Hydrichthys boycei and numerous individuals of three species of fishes—Ambassis natalensis, Mugil sp., and an undetermined fish belonging to the Glyphidodontidæ—in Durban Bay, South Africa. The parasites were attached to various parts of the fishes, especially the fins. At the points of attachment, haustoria were sent down into flesh and into blood-vessels, and by means of these the parasite fed on the tissues of its host. Furthermore, on none of the hydranths were tentacles ever found, nor was any food ever found in them. Strange to say, the parasite never covers any large area of the fish, and apparently presently drops off leaving a scar behind.

     

Brevimulticaecum scleropagi sp. nov. (Ascarididae: Nematoda) from the fish Scleropages jardini in Papua New Guinea

Summary

Examination of ascaridoid nematodes from the osteoglossid fish Scleropages jardini in Papua New Guinea revealed that they belong to a new species and named Brevimulticaecum scleropagi nov. sp. Multicaecum heterotis Petter, Vassiliades and Marchand, 1979 from the African osteoglossid fish Heterotes niloticus was moved to the genus Brevimulticaecum in new combination and reported from the same host in Nigeria and Sudan for the first time. The new species is near to B. heterotis but differs from it in having lips that are not lobed, in the absence of the cervical alae, the much smaller size and measurements of the various organs.     

Geographic variability in the genetic polymorphism of the Isopod,Venezillo evergladensis

Influence of host on hook morphology, soluble protein profile and two polymorphic loci of the marine tapeworms, Hepatoxylon trichiuri and H. megacephalum were studied. It was found that hook lengths of the two parasites differed significantly and that they varied with the host species. Unweighted pair-group analysis of soluble protein similarity indices separated H. trichiuri and H. megacephalum into three groups by fish host species. Allozyme analyses revealed that a polymorphic locus, glucose-6-phosphate dehydrogenase, of H. trichiuri showed significant variations in the allelic and phenotypic frequencies between populations of parasites from different host species, but a second polymorphic locus, esterase, did not show any host-related variation. Owing to the small sample size of H. megacephalum statistical analysis was not carried out for the allozyme study. However, allelic frequencies of the Est locus differed significantly between the two parasites. The possible influence of fish hosts on parasite morphology, protein biochemistry and population genetics was discussed.     

On the new goby,Ctenogobius veliensis (Teleostei: Gobiidae) from the South-West coast of India

Summary

Ctenogobius veliensis, a new species of gobiid fish is described from the South-West coast of India. The characters of the fish conform to those of the genus Ctenogobius Gill but differ markedly from those of other recorded species of the genus. Apart from the usual, external morphological, morphometric and metistic characters, several other features such as the cephalic-lateralis system, skeletal features and morphology of the alimentary canal are also studied and have been found to be of significance for identifying the species. The fish shows distinct sexual dimorphism in many features.     

Diversity and taxonomy of intertidal Bryozoa (Cheilostomata) at Akkeshi Bay,Hokkaido, Japan

We found 39 cheilostome species among more than 7000 specimens collected at 10 intertidal sites in rocky habitats along the shore of Akkeshi Bay, eastern Hokkaido Island, Japan. These species are herein described in detail and illustrated by scanning electron microscopy. Nine species (23% of total) are described as new (Electra asiatica, Callopora sarae, Conopeum nakanosum, Cauloramphus cryptoarmatus, Cauloramphus multispinosus, Cauloramphus niger, Stomachetosella decorata, Microporella luellae, and Celleporina minima), and 21 species (54%) are reported for the first time from Japan. Species richness ranged from eight to 29 species per study site. A TWINSPAN analysis showed the species fell into nine groups defined by the local pattern of distribution. A cluster analysis of study sites based on similarity of species composition showed three faunistic groups distributed geographically: in Akkeshi Lake, along the eastern‐central shore of the bay, and at the mouth of the bay. Species richness in estuarine Akkeshi Lake was low, with a species composition very different from the outer bay. Most cheilostomes were found on rock and shell substrata, but uncommonly occurred on concrete walls, algae, hydroids, tubes of polychaetes, other bryozoans, and anthropogenic debris. Of the 39 species found, 33 (85%) contained embryos during the collecting periods, 2–7 June and 3–6 July 2004. The biogeographical composition of intertidal cheilostomes at Akkeshi Bay included species with Arctic‐Boreal (28%), Boreal (59%), and Boreal‐Subtropical (13%) distributions. The overall species richness of intertidal cheilostomes was two‐thirds that documented intertidally in a comparable study at Kodiak, Alaska, a locality 15° higher in latitude. We attribute the lower richness at Akkeshi to differences in the nearshore marine environment between the two localities.     

Hysterothylacium,Iheringascaris and Maricostula new genus,nematodes (Ascaridoidea) from Australian pelagic marine fishes

The state of knowledge of Australian fish parasitic ascardioids is briefly reviewed. The following species are described in full: Hysterothylacium cornutum, H. pelagicum, H. scomberoidei n. sp. Additional data are provided for Iheringascaris inquies. Maricostula n. gen. is established for those species that have lips with lateral flanges, deep postlabial grooves, interlabia, and elongate intestinal caecum, pyriform ventriculus, long sac-like ventricular appendix, an expanded filamentar excretory system and excretory pore near the nerve ring. The males of all the species have precloacal crests. Species included are: M. caballeroi (Deloya), M. cenatica n. sp., M. histiophori (Yamaguti), M. incurva (Rudolphi), M. makairi n. sp. and M. tetrapteri n. sp. All are recorded from billfishes, and all but M. caballeroi are recorded from Australian waters. The systematic position of the genus is discussed. New characters of taxonomic utility used in the discrimination of fish parasitic ascaridoids are discussed. These include fine details of alae, male caudal crests and papillae. We demonstrate that these characters can be used to separate species of Maricostula. Remarks are also given on nomenclatural problems within the Indo-Pacific fish parasitic Ascardioidea.     

New bariliin cyprinid fishes from West Africa,with a consideration of their biogeography

Five new species of bariliin cyprinid fishes are described from West Africa. Three belong to the genus Leptocypris and two to Raiamas. One species of each genus is from Guinea (Konkoure river) and from Sierra Leone (Taia and Little Scarcies rivers), the other, a Leptocypris, is from Cameroon (Cross River). A taxon of indeterminate generic identity from Guinea is also described. The phylogenetic relationships of the bariliins are hypothesized and in this light their geographical distribution is compared with that of other cladistically analysed African freshwater fish groups. The significance to West African fish distribution of the Togo-Benin (Dahomey) Gap is discussed.     

Deep-sea asellote isopods (Crustacea,Eumalacostraca) of the north-west Atlantic: the family Haploniscidae

The deep-sea asellote isopod species belonging to the family Haploniscidae were studied from three study sites off the North Carolina coast and one off Bermuda. The following five new species, belonging to the new genus Chandraniscus, are described: C. kussakini from Alpha-A off Bermuda (1300 m), C. eastwardae, C. costlowi and C. chardyi from the Carolina lower slope site Beta and C. negoescuae at site Sigma on the Carolina continental rise (4910 m). Three new species of Haploniscus are described: H. kensleyi from the Carolina upper continental slope at Alpha-B, H. gnanamuthi from site Alpha-A off Bermuda, H. harrietae from site Beta. A new species Chauliodoniscus wilsoni from site Sigma is also described. Three new species of the genus Hydroniscus, found in this alpha-taxonomic study, include H. buzwilsoni and H. malyutinae from site Beta and H. watlingi from both Beta and Sigma. Two new species of the genus Antennuloniscus, A. menziesi and A. lincolni, are described from site Beta over the Carolina lower continental slope.     

Ecological investigation of a suspected spawning site of Colorado squawfish on the Yampa River, Utah

On 5 July 1981, 13 adult Colorado squawfish were found in spawning condition at river mile 16.5 in the Yampa River, a major tributary to the Green River. An investigation was undertaken to quantitatively describe this section of the river to gain insights on the spawning requirements of this endangered species. The substrate at the suspected spawning site was cobble with large interstitial spaces devoid of organics, silts, or clays. It appeared that larvae of several fish species utilized these cobble areas and the associated voids. Diurnal sampling indicated that larval drift occurred between 0100 and 0125 hours. Substrate size also appeared to be a dominant factor in fish distribution. Feeding intensities of these fish corresponded to macroinvertebrate drift.         

Occurrence of anisakid larvae (Nematoda: Ascardidia) in fishes from Alaska and Idaho

All 25 sablefish ( Anoplopoma fimbria ) examined from two bays near Sitka, Alaska, were infected with anisakid larvae. There were 1 to 11 larvae per infected fish, with worms encysted in the musculature of the body wall of 5 fish and in the liver of 4 fish. For the other hosts the viscera was the site of infection. Chinook salmon ( Onchorhynchus tshawytscha ) from Barrow, Alaska, and Obsidian, Idaho, were also infected with anisakid larvae. These data extend the known northern distribution of the anisakids along the Pacific Coast for sablefish and chinook salmon. The pathogenesis of the migratory pathway of anisakid larvae is described, and comments on human health implications are presented.     

Exceptional fish yield in a mid-elevation Utah trout reservoir: effects of angling regulations

We used creel surveys to evaluate how a change from a 6-mon to a year-round fishing season affected the sport fish harvest in East Canyon Reservoir (Utah), a 277-ha mesoeutrophic system. Under the year-round season, fishing effort was 840 angler-h . ha -1. yr -1 , and 360 trout ha -1 were captured. Catch rates were proportional to estimated trout densities in the reservoir, ranging from 1.06 during the winter ice fishery, to 0.18 fish angler -1. h -1 in July. Ninety-nine percent of fish harvested were rainbow trout ( Oncorhynchus myskiss ). Thirty-two percent of the 300,000 75-mm fingerling trout stocked annually were captured by anglers within 2.5 yr, but return rates varied with the strain and/or size of trout stocked. Annual fish yield was 102 kg/ha, among the highest yet reported for a temperate zone, lacustrine system. Extending fishing from a 6-mon season to year-round increased the number of fish captured and provided almost twice as many hours of recreational fishing in the reservoir. The harvest period was changed from traditional spring-summer months to primarily a winter-spring fishery because relatively few trout survived for more than 6 mon after reaching harvestable size. Although salmonid production in East Canyon Reservoir is very high, the fishery is in a precarious state because high primary productivity driven, in part, by cultural cutrophication, makes water quality suboptimal during midsummer.     

Metazoan parasite fauna of the round goby Neogobius melanostomus Pallas, 1811 (Perciformes: Gobiidae) collected from the Black Sea coast at Sinop,Turkey

Round gobies (Neogobius melanostomus) were collected from a small stream connected to the Black Sea coast of Sinop, Turkey and examined for metazoan parasites. A total of 122 gobies was investigated throughout a 1‐year period. Long‐term investigations can be useful for finding rare parasites and for determining the diversity and seasonality of parasites. Parasite species recovered were a Digenea gen. sp., Pygidiopsis genata, Ascocotyle sp., Gyrodactylus proterorhini, Dichelyne minutus, Hysterothylacium aduncum, Spiroxys sp., Neoechinohynchus rutilii, and Ergasilus sieboldi. Overall infection prevalence (%) and mean intensity values were 97.5% and 78.2±23.1 parasites per infected fish, respectively. Infection prevalence and mean intensity values for each parasite species in relation to season, fish size, and sex were also determined and discussed.     

Lernanthropus antofagastensis sp. nov. (Copepoda: Lernanthropidae) parasitic on Anisotremus scapularis in Chilean waters,and new records of Lernanthropus trachure (Brian, 1903)

Lernanthropus antofagastensis sp. nov., parasitic on Anisotremus scapularis, and inshore fish of Antofagasta, Chile, is described and illustrated. It resembles five other species of Lernanthropus in its dorsal plate and third leg, but can be distinguished from them by a combination of characters. L. trachuri Brian, 1903, is recorded, its male described and illustrated from specimens collected from Seriolella violacea and Trachurus murphy, taken in the same locality.