THE BARRED MINNOWS (TELEOSTEI: CYPRINIDAE) OF ZIMBABWE: IS THERE CAUSE FOR CONCERN?

Summary

Two species of barred minnow, Opsaridium zambezense and O. peringueyi, occur in Zimbabwe. The former is widely distributed in the Zambezi basin and some other rivers but is now absent from Lake Kariba and possibly some of its tributaries. The latter, which was only recently recognised as a distinct species and admitted to the Zimbabwean list, is much scarcer. It occurs in the Save and Limpopo catchments and there are only four specimens in the Natural History Museum of Zimbabwe collection. These specimens are all more than 40 years old and the lack of more recent ones suggest that O. peringueyi may be extinct, or close to extinction, in Zimbabwe. This situation may have come about through habitat alteration and drought, and emphasises the need for further monitoring of the current occurrence/distribution of fish species in the country.     

Rhipidocotyle genovi n. sp. (Digenea: Bucephalidae) from the intestine ofGaidropsarus mediterraneus (L.) (Gadiformes: Gadidae) from the Black Sea

Rhipidocotyle genovi n. sp. is described from the fishGaidropsarus mediterraneus (L.) (Gadiformes: Gadidae) in the Black Sea. Morphological features characteristic of this species include: an anterior sucker with seven prominent muscular appendages; a pharynx rather posterior in position; ovary and testes relatively anterior in position, usually anterior to the pharynx; a long (in relation to body length) sucker, cirrus-sac and excretory vesicle; the presence of a pre-oral lip; and contiguous vitelline fields which form an arch. The new species is distinguished fromR. galeata, R. lamberti andBucephalus marinum. This is the first member of the genus whose adults are recovered from Black Sea marine fishes. Metacercariae, which encyst in large numbers in the musculature and fins of the blenniid fishesBlennius tentacularis, B. sanguinolentus, B pavo, B. sphinx andB. zvonimiri and exhibit a similar morphology to the adult, are described.     

Gracilaria phuquocensis sp. nov., a new flattened Gracilaria species (Gracilariales,Rhodophyta), previously recognized as G. mammillaris,from the southern coast of Vietnam

Flattened Gracilaria species are widely distributed along the coasts of the South China Sea with more than 20 species recorded. Within the South China Sea, Gracilaria mammillaris has only been reported from Vietnam, but this species is likely restricted to the western Atlantic. This study aimed to reevaluate the taxonomic status of Vietnamese specimens of ‘G. mammillaris’ using combined morphological and molecular data. Our data clearly indicated that Vietnamese specimens were morphologically and genetically distinct from authentic G. mammillaris from the western Atlantic, and also other described flat Gracilaria species. We, therefore, propose that specimens from Vietnam originally identified as G. mammillaris be designated as a new species, Gracilaria phuquocensis sp. nov. Morphologically, G. phuquocensis can be distinguished from other flat Gracilaria species by its small thallus size, narrower blades, many medullary layers, abundant basal nutritive filaments within mature cystocarps, and tetrasporangial nemathecium. Our rbcL sequence analyses showed that the new species was sister to Gracilaria rhodymenioides from Thailand, and these two species formed a clade with cylindrical Gracilaria species. Our study contributes to clarification of the taxonomic status of misidentified specimens attributed to the flattened Gracilaria species in the South China Sea.     

Boschmaella japonica,New Species,a Parasite on the Barnacles Chthamalus challengeri and Balanus amphitrite amphitrite from Japan (Crustacea: Cirripedia: Rhizocephala: Chthamalophilidae)

Abstract A new rhizocephalan parasite which infests the barnacles Chthamalus challengeri and Balanus amphitrite amphitrite is described. It is known only from the type locality, Aburatsubo, Kanagawa Prefecture, Japan. Its position in the family Chthamalophilidae is assured by the cyprids lacking a thorax, by the position of the mesenteric canal opposite to the stalk, and by its host being a balanomorph barnacle. Among the three previously described species of the Chthamalophilidae, the new species most closely resembles Boschmaella balani, but it differs in details of the internal root system and in the externa being found both on the host body and on the inner mantle. About two-thirds of the infested hosts carry more than one externa.     

Ciliary receptors associated with the mouth and pharynx of Acoela (Acoelomorpha): a comparative ultrastructural study

The ultrastructure and distribution of receptor cells near the mouth and (where present) the pharynx of Hofstenia miamia, Proporus bermudensis, Conaperta thela, and Convoluta convoluta (Acoela) were investigated by transmission electron microscopy and confocal laser scanning microscopy of specimens stained with a fluorescence marker for actin. Five types of monociliary receptors were identified: (1) non‐collared receptors with a single long and narrow ciliary rootlet; (2) non‐collared receptors with a wide main ciliary rootlet and a smaller posterior rootlet; (3) non‐collared receptors with a single wide and hollow ciliary rootlet with a granulated core; (4) Collar (?) receptors with obliquely radial filament bundles in the cell apex and with a single hollow ciliary rootlet composed of numerous strand‐like elements; and (5) Collar receptors lacking a striated rootlet but with a granular body (swallow's nest rootlet). While H. miamia bears the first two receptor types, P. bermudensis has receptors of type 1, 3 and 5, and Cona. thela and Conv. convoluta have receptors of type 3, 4 and 5. The density of receptors is generally highest at the anterior body tip, regardless of where the mouth is located. Most receptor types occur scattered over the whole body but type 2 receptors of H. miamia are restricted to the pharynx and mouth region. The lack of a common receptor type specific for the mouth and pharynx of the investigated species points to an independent origin of the pharynges in Hofsteniidae and in Proporidae and of the mouth tube in Convolutidae. Moreover, the homology of the so‐called collar receptors in Acoela with typical collar receptors in other invertebrates is questioned.     

Orthocoelium serpenticaecum (Paramphistomidae: Orthocoeliinae), a new species from the swamp buffalo (Bubalus bubalis Linnaeus) in the Philippines

Orthocoelium serpenticaecum n. sp. is described and illustrated from specimens collected from the swamp buffalo (Bubalus bubalis Linnaeus) in the Philippines. It is readily distinguished from all species of the genus by the tortuous dorso-ventral bends of the caeca and the different types of pharynx and terminal genitalium which are described as ‘serpenticaecum types’ (new types). Supported by a research grant (No. 8301 Ag) from the National Science and Technology Authority (NSTA) Assisted University of the Philippines System (UPS) Integrated Research Program.     

The fine structure of mature spermatozoids of Chara corallina,with special reference to microtubules and scales

Summary New features recorded here for the first time include demonstration of the presence of a covering of tiny diamond shaped scales all over the body of the helical cell of the mature spermatozoids of Chara corallina Klein ex Willd. as well as a covering of slightly larger diamond shaped scales over the surfaces of the two flagella which has previously been seen by other authors in spermatozoids of both Chara and Nitella.The arrangement of microtubules in the anterior end of the spermatozoid, as a layer completely surrounding the anterior row of mitochondria resembles that of Chara fibrosa described by Pickett-Heaps 1968 and differs from that described for Nitella missouriensis by Turner 1968; these details are therefore perhaps phyletically significant.Other features such as the partial degeneration of the anteriorly placed flagellar bases are similar to those previously described for these two species although the distance between the bases and the point of emergence of the flagella from the body surface seems to differ somewhat from species to species.The investigation includes observations on the dehiscence of the antheridia and on the emergence of living cells from the spermatogenous filaments.The possible phyletic significance of some of these observations is discussed in a preliminary way.     

A new moray eel (Gymnothorax: Muraenidae) from Japan and Hawaii

A new muraenid,Gymnothorax ypsilon, is described from seven specimens from Japan and four from the Hawaiian Islands. It has about 30 narrow dark bars on the body, some of which are Y-shaped on most specimens, a uniformly colored head, an anal fin with a white margin, and 141–153 vertebrae. It differs fromG. pikei, its most similar species, by a white margin of the anal fin.     

Deep-sea parasitic nematodes of the genus <Emphasis Type="Italic">Trophomera</Emphasis> Rubtsov et Platonova, 1974 (Benthimermithidae) from the Equatorial Atlantic,with the descriptions of two new species

Nematode females of the genus Trophomera (Benthimermithidae) from the collection of the Smithsonian’s National Museum of Natural History (Washington, DC, USA) were examined. Nematodes were collected in different parts of the Western Atlantic (Hatteras Abyssal Plain, Brazil Basin, and Argentina Basin) from depths of 467–5,223 m. Two new species are described. Body length of T. americana sp. n. is 3,250–4,470 μm; posterior end conical with rounded tip; cephalic setae about 3–4 μm long; trophosome consisting of several longitudinal rows of large cells; ovaries reflected; mature eggs 35 μm in diameter. Body length of T. longiovaris sp. n. is 7,870–15,400 μm; posterior end conical with rounded tip; cephalic sensilla 7 μm long; mouth opening vestigial, present as very narrow apical pore; pharynx devoid of internal lumen and muscular envelope; midgut represents a trophosome without internal lumen; trophosomal cells arranged in 3–4 longitudinal rows; rectum and anus vestigial; female reproductive system didelphic, amphidelphic, very long, occupying about 0.8 total body length; ovaries telogonic, outstretched; oviducts very long, repeatedly folded across body axis; proximal parts of oviducts being than distal ones, uterus distinctly formed. New finds of two known species, T. arnauidi and T. marionensis, are also recorded and described.     

Active generation glands present in neonates of some Cordylid Lizards: A case study of Cordylus macropholis (Sauria: Cordylidae)

Generation glands are holocrine epidermal glands occurring on the ventral aspect of the thigh of cordylid lizards. In most species these glands seemingly start to differentiate with the onset of sexual maturity, but macroscopic signs of generation gland activity were noted in neonates of the large-scaled girdled lizard, Cordylus macropholis. The glands of neonatal, subadult, and adult individuals were examined microscopically using standard histological techniques. The glands of the five neonatal specimens examined, including both males and females, all had the same basic structure and displayed two layers of mature glandular material. In subadult and adult specimens, the number of layers varied from seven to nine. The structure of the generation glands of C. macropholis is similar to that of the few other Cordylus species that have been described to date. They are of the protruding kind with multiple mature glandular generations. Juveniles of an additional 12 cordylid species have been examined for the presence of active generation glands. Active glands were found to be present in neonates of C. tasmani and C. tropidosternum, both of which are, like C. macropholis, terrestrial species. In C. cordylus and C. coeruleopunctatus, active generation glands are absent in neonates, but differentiate soon after birth. In other cordylid species, generation glands apparently differentiate only with the onset of sexual maturity. J. Morphol. 235:177–182, 1998. © 1998 Wiley-Liss, Inc.     

Histology and morphometrics of testes of the white-sided dolphin (Lagenorhynchus acutus) in bycatch samples from the northeastern Atlantic

The testes of 31 Atlantic white-sided dolphins, Lagenorhynchus acutus bycaught in the northeastern Atlantic were studied by histological and morphometric techniques. Twenty specimens were classified as mature, nine as immature and two as pubescent. Between immature and mature specimens there were overlappings in body length and body weight, but clear differences in the diameter of seminiferous tubules (<80 and >80 μm) and the proportion of seminiferous tubules to interstitial tissue (ST:INT-ratio). Also relative testes weight differed clearly. The pubescent specimens showed intermediate characteristics. Spermatogenetic activity of mature dolphins ranged from quiescent to different degrees of activity and varied even in animals from the same site and capture date. The fact that we found mature males with quiescent testes suggests a seasonal rather than a continuous spermatogenesis. We assume that sexual activity in L. acutus begins at an age of 7–8 GLGs and that the reproductive season of this species in the northeastern Atlantic starts in February. Further, the ultrastructure of the spermatozoon is similar to that of the related Lagenorhynchus obliquidens.     

A New Species of Nematodes Found in Rotting Seaweed on the Shore of the Black Sea

A new species of nematodes, Pellioditis obesasp. n., found in rotting seaweed in the supralittoral area of the Black Sea near Sevastopol (Ukraine) is described and illustrated. The new species is morphologically similar to P. ehrenbaumi(Bresslau and Sch. Stekhoven, 1935); but it differs in having a narrow protostoma cylinder, a shorter female tail, larger eggs, longer spicules and gubernaculum, and in the ratio of the anterior pharynx length to the posterior pharynx length.     

Southernmost records of bottlenose dolphins, Tursiops truncatus

Bottlenose dolphins (Tursiops spp.) are cosmopolitan animals widely distributed in waters of both hemispheres. The taxonomy of Tursiops has long been controversial, with over 20 specific names being published, and subspecies and inshore/offshore forms being proposed. In the southwestern South Atlantic, subspecies T. truncatus truncatus and T. truncatus gephyreus were proposed for specimens along the coasts of Brazil, Uruguay, and Argentina. Sightings of bottlenose dolphins are common along the coast of Argentina as far south as the Province of Chubut (ca. 46°S). Here, we summarize and discuss the southernmost records of bottlenose dolphins. We cannot make inferences about the species or subspecies to which these animals belong given the small number of specimens. Future studies of external measurements, pigmentation, DNA, and isotopes from both sides of the continent should help clarify the situation off southern South America. Furthermore, research is needed to explore a possible link between an effect of general global warming and the Tursiops specimens found this far south. The sighting and specimens described here, at 53°S–nearly 55°S, are the southernmost records for the genus and extend the range of the species in the southern South Atlantic.     

Revision of genus Melamphaes (Melamphaidae). II. Multi-Raker species: M. polylepis, M. falsidicus sp. nova, M. pachystomus sp. nova, M. macrocephalus, M. leprus

The second part of the publication is devoted to the Melamphaes species (family Melamphaidae), which are characterized by 20 and more rakers on the first gill arch, by seven soft rays in the ventral fin, by absence of a temporal spine, by 14–15 rays in the pectoral fin, and by 11 abdominal vertebrae. M. polylepis is characterized by circumtropical range (Atlantic Ocean, Indian Ocean, western and central Pacific Ocean). Newly described species M. falsidicus is described from the northern Atlantic Ocean, where it was sampled between 34°N and 58°N. Before, this species was defined as M. microps. Another newly described species, M. pachystomus, is described along the Peruvian Coast. M. macrocephalus is redescribed. This species inhabits the eastern tropical Pacific Ocean (approximately between 30°N and 23°S). One of the studied specimens of M. macrocephalus was characterized by larger body size (SL = 128 mm) than was described before for this species. M. leprus is known currently by single findings from the eastern tropical Atlantic Ocean (between 11°N and 4°S). This species was also found in the samples obtain in the Gulf of Guinea.     

Development of the reproductive apparatus of the land planarian Rhynchodemus sylvaticus (Turbellaria: Tricladida) and its significance for classification in the genus

Seven specimens of Rhynchodemus sylvaticus (Leidy) collected from a variety of localities in the US and having variously developed copulatory organs are believed to represent stages in the development of the copulatory apparatus. Four specimens were juveniles with under-developed male components, one specimen had a well-developed female atrium and small male component, and two specimens were mature with a male organ twice the size of the female part. In early stages, the male component had sperm ducts, seminal vesicle, and narrow atrium; more mature stages had a considerable elongated atrium with thick folds in its muscularized wall, a massive muscular bulbus; and a sigmoid ejaculatory duct opening into the large bulbar cavity. Morphological features of mature male copulatory organs in all species of the genus Rhynchodemus are basically similar whereas external body features (color and number of dorsal stripes) of these same species differ.     

Geographic distribution and environmental control of vertebral count in Ammodytes spp. along the northern Pacific coast of Japan

To examine species composition and population structures in sand lance (Ammodytidae) along the northern Pacific coast of Japan, genetic analysis were carried out for specimens collected in 2014 from Otsuchi Bay, Iwate, Ishinomaki Bay, Miyagi, off Soma, Fukushima and Ise–Mikawa Bays, Aichi. The samples consisted of Ammodytes japonicus and Ammodytes heian, of which the latter is a recently described species. Neither species exhibited significant genetic differences among localities. Only A. japonicus was found in the most southern locality at Aichi, but it decreased northward to <90% in Miyagi and Fukushima and the two species occurred almost evenly in Iwate suggesting a latitudinal cline in their species composition along the northern Pacific coast of Japan, off Tohoku. The vertebral counts differed between A. japonicus and A. heian with modes of 65 and 63, respectively, but this characteristic did not differ significantly within a locality (Iwate). This suggests that the vertebral counts of Ammodytes spp. in Japanese waters are probably strongly determined by the environment than by a species‐specific genetic trait.     

A redescription of the Shantar snailfish, Liparis schantarensis (Scorpaeniformes: Liparidae), with new records from the southeastern Kamchatka Peninsula

Validity of the species Liparis schantarensis (Lindberg and Dulkeit, 1929) (Scorpaeniformes: Liparidae) is confirmed and redescribed based on six new specimens collected in Avacha Bay on the southeastern Kamchatka Peninsula. These specimens are the first records of this species reported in more than 70 years and the first outside the Sea of Okhotsk. Distinguished from almost all other members of the genus Liparis by a comblike anteriormost part of the dorsal fin, both males and females have 5–7 elongated anterior dorsal fin rays, with the distal ends free of the membrane for about one-half to two-thirds the length of the ray.