Phylogenetic relationships of sculpin <Emphasis Type="Italic">Cottus volki</Emphasis> Taranetz, 1933 (Scorpaeniformes,Cottidae) according to the results of analysis of control region in mitochondrial DNA

Sequencing of the fragment of control region in mitochondrial DNA in sculpin Cottus volki and the comparison of obtained data with homologous nucleotide sequences in the other species from genus Cottus demonstrated that C. volki occupies the basal position in the “poecilopus” group, which includes also typical sculpin C. poecilopus Heckel, 1837 from water bodies of Europe, sculpin C. szanaga Dybowski, 1869 from the Amur River basin, and sculpin Cottus cf. poecilopus from the Lena River basin. Early separation of C. volki line from common trunk of “poecilopus” group explains the presence in C. volki of several primitive (plesiomorphic for this group) morphological characters: long interior ray of ventral fin, practically complete lateral body line, and well-developed dentition of palatine bones.     

Two New Species of Goby of the Genus <Emphasis Type="Italic">Astrabe</Emphasis> from Japan

Two species of goby belonging to the genus Astrabe are described from Japan as new species, A. flavimaculata and A. fasciata. A. flavimaculata is distinguishable from A. lactisella, the type species and hitherto the only known species of the genus, in that it has no protrusion on the upper posterior part of the dermal fold along the upper margin of the eye, fewer scales in a longitudinal row, predorsal scales, scales on the belly, a narrower white transverse band across the base of the pectoral fins, and in life yellow markings on a dark brown ground colour except for the white transverse band across the base of the pectoral fins. A. fasciata is distinguishable from A. lactisella in that it has fewer scales in a transverse row, a narrower scaled area on the lateral side of the body, a narrower white transverse band across the base of the pectoral fins, and a white transverse band across the anterior part of the 1st dorsal fin extending to the ventral side of the body.     

Description of the new subgenus <Emphasis Type="Italic">Metoporaphodius</Emphasis> subgen. n. of the genus <Emphasis Type="Italic">Aphodius</Emphasis> Helw. (Coleoptera,Scarabaeidae) and of the larva of its type species, <Emphasis Type="Italic">A. plustschewskii</Emphasis> D. Kosh.

The new Irano-Turanian subgenus, Metoporaphodius subgen. n., is erected in Aphodius Helw. for A. plustschewskii D. Kosh. (type species) and A. baghlanicus Frolov. The males of Metoporaphodius subgen. n. are distinguished by the presence of a comb of dense setae on hind tibia and by the parameres with spatulate projections. The 3rd instar larva of A. plustschewskii has 2 rows of large flattened spinules on anal stemite (with 10-12 spinules in a row), and 3 spinules on the lacinial apex.     

The ammonoid genus <Emphasis Type="Italic">Spiroceras</Emphasis> (Spiroceratidae,Ammonoidea) from the Upper Bajocian of the Northern Caucasus

Ammonites of the genus Spiroceras are described from the Upper Bajocian of the Kyafar River Basin (Karachay-Cherkessia), including macroconchs with preserved apertures and (for the first time in the entire history of the study of Middle Jurassic heteromorphs) microconchs with lateral lappets. The microconchs of S. bispinatum (Baugier et Sauzé), mainly represented by cyrtocones with one ventral row of nodes, correspond to microconchs with a gyroconic shell and a single row of nodes. Macroconchs and microconchs of S. annulatum (Deshayes), the ribs of which lack prominent nodes or spines, are found together. The assemblage also contains small-sized slightly uncoiled shells of Spiroceras aff. S. fourneti Roman et Pétouraud with widely spaced ribs and two prominent rows of large nodes, presumably macro- and microconchs. The ornamentation of this species resembles that of the monomorph Bajocia rarinoda Sturani from the upper part of the Lower Bajocian; perhaps the latter was ancestral to the Middle Jurassic heteromorph. The above species of Spiroceras, as well as S. obliquecostatum (Quenstedt), are figured.     

A new species of <Emphasis Type="Italic">Psidium</Emphasis> from western Ecuador

Psidium guayaquilense from western Ecuador is described and illustrated. It is most similar to P. acidum, having in common with it non-angular, rounded seeds, anthers with a few subequal glands and peduncles with wings. Psidium guayaquilense differs from P. acidum in various ways, most notably in the principal marginal veins mainly 1–3 mm from margin (versus 3–10 mm or more from margin in P. acidum); closed calyx with a prominent apiculum (versus without an apiculum or with only a weak apiculum); ovules per locule 12–40 (versus 50–70); style 8–10 mm long (versus 12–16 mm); fruit 1.5–3 cm in diameter (versus 2–5 cm); fruit wall 0.5–2.5 mm thick (versus 4–13 mm); seeds usually 4–6 (versus 20–60 or more).     

Description and ecology of larvae and juveniles of three native cypriniforms of coastal southern California

Larval series of the Santa Ana sucker, Catostomus santaanae (Federally Threatened), arroyo chub, Gila orcutti (California Species of Special Concern), and Santa Ana speckled dace, Rhinichthys osculus (California Species of Special Concern) are described from wild-caught specimens from the Los Angeles and Santa Ana river drainages. Santa Ana sucker larvae are elongate, having 41–46 myomeres and a distinctive paired-triangle patch of melanophores over the midbrain. Melanophores present on the snout, dorsal body, lateral midline, dorsal gut, postanal ventral body, and caudal fin. Preanal length 74–79% in body length (BL), typical of catostomids. Arroyo chub larvae relatively deep-bodied, 36–39 myomeres, and a heart-shaped patch of melanophores over the midbrain with a line of melanophores trailing posteriorly. Heavy pigment present on the snout, lower jaw, dorsal body, lateral midline, gill arches, dorsal gut, postanal ventral body, and caudal fin; short preanal length of 65–72% BL, typical of native North American cyprinids. Santa Ana speckled dace are similar to arroyo chub except for having less pigment on the ventral gut, large distinct melanophores on the ventrolateral caudal peduncle, a wedge-shaped patch of midbrain melanophores with no distinct line trailing posteriorly, and lateral midline melanophores that do not extend anteriorly. These three species often occur together and with nonnative cyprinids. Characters distinguishing them from other local larvae, including southern fathead minnow, Pimephales promelas confertus and red shiner, Cyprinella lutrensis, are discussed with their habitat preferences.     

<Emphasis Type="Italic">Oredezhosteus</Emphasis>, a new psammosteid genus (Heterostraci,Psammosteiformes) from the Lower Frasnian (Upper Devonian) of the Main Devonian Field

A new psammosteid, Oredezhosteus kuleshovi gen. et sp. nov., from the Amata Regional Stage (Lower Frasnian) of the Leningrad Region is described. In addition, Psammosteus livonicus Obruchev from beds of the same age from Latvia is included in the new genus. The major diagnostic characters distinguishing Oredezhosteus gen. nov. from Psammosteus Agassiz are the large rounded striated tubercles, which cover more than half width of the branchials, and the long base of the branchial plates.     

Salmonid fish: model organisms to study cardiovascular morphogenesis in conjoined twins?

Background

There is a gap in knowledge regarding the cardiovascular system in fish conjoined twins, and regarding the cardiovascular morphogenesis of conjoined twins in general. We examined the cardiovascular system in a pair of fully developed ventrally conjoined salmonid twins (45.5 g body weight), and the arrangement of the blood vessels during early development in ventrally conjoined yolk sac larvae salmonid twins (<0.5 g body weight).

Results

In the fully developed twins, one twin was normal, while the other was small and severely malformed. The mouth of the small twin was blocked, inhibiting respiration and feeding. Both twins had hearts, but these were connected through a common circulatory system. They were joined by the following blood vessels: (i) arteria iliaca running from arteria caudalis of the large twin to the kidney of the small twin; (ii) arteria subclavia running from aorta dorsalis of the large twin to aorta dorsalis of the small twin; (iii) vena hepatica running from the liver of the small twin into the sinus venosus of the large twin. Among the yolk sac larvae twins investigated, distinct vascular connections were found in some individuals through a joined v. vitellina hepatica.

Conclusions

Ventrally conjoined fish twins can develop cardiovascular connections during early development, enabling a normal superior twin to supply a malfunctioning twin with oxygen and nutrients. Since the yolk sac in salmonids is transparent, twinning in salmonids may be a useful model in which to study cardiovascular morphogenesis in conjoined twins.

     

New taxa of oribatid mites from Korup National Park,Cameroon. Genus <Emphasis Type="Italic">Galumna</Emphasis> (Acari,Oribatida, Galumnidae)

Two new species of oribatid mites of the genus Galumna (Oribatida, Galumnidae) are described from litter and soil in the Korup National Park, Cameroon. Galumna korupensis sp. n. differs from Galumna tricuspidata Engelbrecht, 1969 by the smaller body size, the presence of two oval postanal porose areas, one tooth on each lamellar lines and striate genital plates, and the absence of median pore and lateral teeth on the rostrum. Galumna cameroonica sp. n. differs from Galumna incisa Mahunka, 1982 by the presence of long cilia on bothridial heads, band-like postanal porose area, striate genital plates, three pairs of notogastral porose areas, and the position of notogastral lyrifissures im.     

Revision of <Emphasis Type="Italic">Podocotyloides</Emphasis> Yamaguti, 1934 (Digenea: Opecoelidae), resurrection of <Emphasis Type="Italic">Pedunculacetabulum</Emphasis> Yamaguti, 1934 and the naming of a cryptic opecoelid species

Despite morphological and ecological inconsistencies among species, all plagioporine opecoelids with a pedunculate ventral sucker are currently considered to belong in the genus Podocotyloides Yamaguti, 1934. We revise the genus based on combined morphological and phylogenetic analyses of novel material collected from haemulid fishes in Queensland waters that we interpret to represent species congeneric with the type-species, Pod. petalophallus Yamaguti, 1934, also known from a haemulid, off Japan. Our phylogenetic analysis demonstrates polyphyly of Podocotyloides; prompts us to resurrect Pedunculacetabulum Yamaguti, 1934; and suggests that Pod. brevis Andres & Overstreet, 2013, from a deep-sea congrid in the Caribbean, and Pod. parupenei (Manter, 1963) Pritchard, 1966 and Pod. stenometra Pritchard, 1966, from mullids and chaetodontids, respectively, on the Great Barrier Reef, may each represent a distinct genus awaiting recognition. Our revised concept of Podocotyloides requires a pedunculate ventral sucker, but also a uterine sphincter prior to the genital atrium, a petalloid cirrus appendage, restriction of the vitelline follicles to the hindbody, and for the excretory vesicle to reach to the level of the ventral sucker. Of about 20 nominal species, we recognise just three in Podocotyloides (sensu stricto): Pod. petalophallus, Pod. gracilis (Yamaguti, 1952) Pritchard, 1966 and Pod. magnatestes Aleshkina & Gaevskaya, 1985. We provide new records for Pod. gracilis, and propose two new species of Podocotyloides, Pod. australis n. sp. and Pod. brevivesiculatus n. sp., and one new Pedunculacetabulum species, Ped. inopinipugnus n. sp., all from haemulids. Podocotyloides australis is morphologically indistinguishable from Pod. gracilis, and exploits the same definitive host, but is genetically and biogeographically distinct. It is thus a cryptic species, the first such opecoelid to be formally named.     

Poorly known stonefly species, <Emphasis Type="Italic">Isoperla pseudornata</Emphasis> and <Emphasis Type="Italic">Kaszabia nigricauda</Emphasis> (Plecoptera,Perlodidae), from the Eastern Palaearctic

The previously unknown male of Isoperla pseudornata Zhiltzova and nymph of Kaszabia nigricauda (Navás) of the family Perlodidae are described. Sternite VIII of the male of I. pseudornata has no vesicle, the posterior margin is covered medially with strong short brownish setae. Sternite IX forms a subgenital plate. The everted aedeagus is upcurved, turned towards the dorsum, with two rounded lobes and one finger-shaped apical lobe terminating with a membranous funnel depressed medially. The aedeagus membrane is covered with small fine pointed sclerotized spinules; spinules absent on the tip of the funnel. The funnel basally and the finger-shaped apical lobe ventrally are covered with fine pointed sclerotized spinules and rounded sclerotized formations. I. pseudornata differs from the other Eastern Palaearctic congeners in the shape of spots on the head, pronotum, and abdominal tergites. The head of K. nigricauda nymph bears a large brown M-shaped spot forming along the anterior margin two fine stripes widened on the frontoclypeus; the interocular area bears a small pale spot merged with the large transverse W-shaped spot on the occiput. The lacinia is narrowed to the apex, bidentate; the tip of the galea reaches the base of the subapical tooth. The pronotum bears a pale cruciform medial spot, the lateral fields are dark, the lateral margins are pale. The meso-and metanotum exhibit a pale complicated pattern widened to the base of the wing pads. The legs are pale. The abdominal tergites are brown, with a pale transverse stripe widened laterally on the last tergites. Tergite X bears a large pale heart-shaped spot medially. The cerci bear a silky hair fringe dorsally; in the apical part, the apical whorl of cerci has short setae; one ventral and one dorsal seta are longer than the others; the dorsal setae are longer than ventral ones.     

<Emphasis Type="Italic">Mayarhynchus karlae</Emphasis> n. g., n. sp. (Acanthocephala: Neoechinorhynchidae), a parasite of cichlids (Perciformes: Cichlidae) in southeastern Mexico,with comments on the paraphyly of <Emphasis Type="Italic">Neoechynorhynchus</Emphasis> Stiles &amp; Hassall, 1905

Mayarhynchus n. g. (Acanthocephala: Neoechinorhynchidae) is erected for Mayarhynchus karlae n. g, n. sp. described from the intestine of four species of cichlid fishes distributed from southeastern Mexico. The new genus placed in the family Neoechinorhynchidae (Ward, 1917) Van Cleave, 1928, is readily distinguished from the other 17 genera in the family by having a small proboscis armed with 45–46 relatively weak rooted hooks arranged in nine longitudinal rows of five hooks each. In addition, Mayarhynchus n. g., n. sp. is diagnosed by the presence of a short trunk, body wall with five dorsal and one ventral giant hypodermal nuclei, proboscis receptacle nearly cylindrical with single layered wall, lemnisci broad and flat with large nuclei, testes in tandem, cement gland with eight large nuclei, and eggs elongate to oval. Partial sequences of the cytochrome c oxidase subunit 1 (cox1), internal transcribed spacers (ITS1 + 5.8S + ITS2), and the D2-D3 domains of the large subunit rRNA gene (28S) were obtained for five specimens of the new species and other species belonging to the Neoechinorhynchidae. Phylogenetic analyses confirmed that the new genus belongs to the Neoechynorhynchidae and indicated that the genus Neoechynorhynchus Stiles & Hassall, 1905 is not monophyletic. Comparison between three populations of the new species yielded nine variable sites for cox1, 11 for ITS and four for 28S.     

Does breeding ecology alter selection on developmental and life history traits? A case study in two Ambystomatid salamanders

Terrestrial breeding with extended incubation has evolved repeatedly in fishes and amphibians but raises challenges for embryos, which must conserve sufficient yolk to continue development until water is available. One means of avoiding premature yolk consumption is for embryos to slow their development such that yolk is consumed more slowly. However slower development is associated with smaller adult body sizes and lower survivorship, particularly in amphibians occupying ephemeral habitats. The variable breeding strategies of Ambystomatid salamanders provide an excellent system in which to examine whether variation in breeding ecology is associated with divergence in embryonic development. Phylogenies of Ambystoma strongly support aquatic egg-laying and winter breeding as ancestral. Early breeding has evolved in three species and terrestrial breeding in two of the three. We propose that early, terrestrial breeding has altered selection on embryonic development. In particular, we propose that the prolonged incubation typically associated with early, terrestrial breeding has selected for longer development times. We compared embryonic development of the terrestrial breeding Ambystoma opacum (Gravenhorst 1807) with the co-occuring, aquatic breeding Ambystoma maculatum (Shaw 1802) under a range of laboratory conditions over two breeding seasons. We found that A. opacum embryos took longer to develop and hatched at a later stage, consistent with the hypothesis that early, terrestrial breeding favors embryos that extend development.     

Redescription of <Emphasis Type="Italic">Cottus sibiricus</Emphasis> and an estimation of differences between this species and <Emphasis Type="Italic">Cottus dzungaricus</Emphasis> (Cottidae)

The type specimens of Cottus sibiricus and C. dzungaricus as well as individuals from the Olkha River (Yenisei River basin) are studied. The diagnostic features of C. sibiricus are established. Comparative morphological and molecular analysis of divergence between C. sibiricus and C. dzungaricus demonstrates that the differences lie within the limits of one polymorphous species. The rank of Dzungarian sculpin is lowered to the subspecies, C. sibiricus dzungaricus.     

Three new species of <Emphasis Type="Italic">Plagioporus</Emphasis> Stafford, 1904 from darters (Perciformes: Percidae), with a redescription of <Emphasis Type="Italic">Plagioporus boleosomi</Emphasis> (Pearse, 1924) Peters, 1957

A form of Plagioporus Stafford, 1904 is described from the intestine of three North American species of darters (Perciformes: Percidae) from River West Twin, Wisconsin, USA, that we consider to be conspecific with Plagioporus boleosomi (Pearse, 1924) Peters, 1957 based on similarities in the sucker ratio, extent of the forebody, shape and position of the testes, vitellarium distribution and terminal genitalia. Three new species of Plagioporus are described from the intestine of darters as follows: Plagioporus fonti n. sp. from Percina nigrofasciata Agassiz in Florida, USA, Plagioporus limus n. sp. from Etheostoma squamosum Distler in Arkansas, USA and Plagioporus aliffi n. sp. from Etheostoma blennioides newmanni Miller in Arkansas, USA. Morphologically Plagioporus fonti n. sp., Plagioporus limus n. sp. and Plagioporus aliffi n. sp. are most similar to one another and to P. boleosomi, Plagioporus lepomis Dobrovolny, 1939 and ‘P. etheostomae’, a nomen nudum for a species described from Etheostoma blennioides Rafinesque in Kentucky, USA, all of which are collectively distinguished from congeners in having a combination of confluent vitellarium in the post-testicular space and absence of vitelline follicles with their entire length distributed in the forebody. Plagioporus fonti n. sp., P. limus n. sp. and P. aliffi n. sp. are respectively distinguished from one another and their closest congeners in having the anterior extent of the vitellarium in the anterior half of forebody to slightly anterior to the ventral sucker as opposed to one approximately at the level of the posterior margin of the ventral sucker, possession of an excretory vesicle reaching the anterior testis as opposed to one only reaching the posterior testis and having a longer than wide oral sucker and a wider than long ventral sucker. A Bayesian inference (BI) analysis of partial 28S rDNA sequences was conducted using the three new species and 24 sequences of opecoelids retrieved from GenBank, including ten species of Plagioporus. Plagioporus aliffi n. sp., Plagioporus fonti n. sp. and P. boleosomi comprised a moderately supported sister group to a clade containing all species of Plagioporus except Plagioporus limus n. sp. and Plagioporus shawi (Mcintosh, 1939) Margolis, 1970. Plagioporus limus and in turn P. shawi were resolved as sister to all other congeners with high and moderate support, respectively.     

Redescription of <Emphasis Type="Italic">Lagocephalus cheesemanii</Emphasis> (Clarke 1897), a senior synonym of <Emphasis Type="Italic">Lagocephalus gloveri</Emphasis> Abe and Tabeta 1983, based on morphological and genetic comparisons (Actinopterygii: Tetraodontiformes: Tetraodontidae)

Lagocephalus gloveri Abe and Tabeta 1983 is shown to be a junior synonym of Tetrodon cheesemanii Clarke 1897 based on examination of morphological characters and DNA analysis of specimens collected from the western North Pacific, Australia and New Zealand. Lagocephalus cheesemanii is distinguished from other species of Lagocephalus by the following combination of characters: spinules on the back in a rhomboidal patch extending from the region between the nasal organ to the posterior part of the pectoral fin; caudal fin double emarginate with middle rays posteriorly produced; dorsal-fin rays 11–15; anal-fin rays 11–14; pectoral-fin rays 15–18; vertebrae 8+11=19; dorsal half of the body dark brown to brownish black; caudal fin dark brown to black with dorsal and ventral white tips. A neotype of L. cheesemanii is designated.     

Leptocephalus larvae of two moray eels (Anguilliformes; Muraenidae), Gymnothorax sagmacephalus and Gymnothorax albimarginatus,identified from morphometric and genetic evidence

Two forms of muraenid leptocephali, collected from the western Pacific Ocean, were identified as Gymnothorax sagmacephalus Böhlke 1997 and Gymnothorax albimarginatus (Temminck and Schlegel 1846) on the basis of morphometric and genetic analyses. The leptocephali of each species were characterized, respectively, by counts of 172–175 and 186–191 myomeres, 43–44 and 47 predorsal myomeres, 109–113 and 127–134 preanal myomeres, and 100–104 and 118–119 last vertical blood vessel myomeres. Gymnothorax sagmacephalus leptocephali had minute melanophores over much of the head and body, closely resembling the condition in Gymnothorax minor (Temminck and Schlegel 1846), whereas those of G. albimarginatus not only had minute melanophores over much of the head and body, but also a pair of melanophore groups on the posteroventral and posterodorsal aspects of the head. Such groups are here considered to represent highly specific characters. Although a previous opinion postulated that G. sagmacephalus is a juvenile of G. albimarginatus, and the adult morphologies of the two species have a lot in common, they clearly differ in both leptocephalus morphology and genetic sequence. Therefore, G. sagmacephalus was concluded as being a valid species.     

Description of Adult and Fourth-Stage Larva of <Emphasis Type="Italic">Litomosoides navonae</Emphasis> n. sp. (Nematoda: Onchocercidae), a Parasite of Five Species of Sigmodontine Rodents from Northeastern Argentina

This study describes a new species of Litomosoides Chandler, 1931, parasitic in five different sigmodontine rodents from Misiones, Chaco and Formosa provinces of Argentina. The fourth-stage (L4) larva (male and female) is also described. L. navonae n. sp. exhibits: a bottle-shaped buccal cavity; a buccal capsule with irregularly crenate external walls; four externo-labial papillae and one ventral cephalic papilla; a well differentiated oesophagus; and sigmodontis-type spicules. The microfilaria is fusiform, with a large sheath. The L4 has a buccal capsule which is relatively longer than that of the adults, with narrower walls and a bottle-shaped lumen. It was observed in this species that the oesophagus/body-length ratio increases from larva to adult (female ratio 26.2–28.3 in larva; 88.4 in adults), and the vulva appears to move further posterior to the oesophago-intestinal junction (200–300 μm in larvae vs a mean of 600 μm in adults). L. navonae was found parasitising: Nectomys squamipes from the Reserve UNLP Valle del Arroyo Cuñá Pirú, Misiones; Oligoryzomys chacoensis, Holochilus chacarius and Akodon azarae bibianae from the marshes of Arroyo Bellaco, El Colorado, Formosa; and O. fornesi and H. chacarius from Selvas del Río de Oro (Chaco). Both N. squamipes and H. chacarius harbour other filarioids species, i.e. L. kohnae Bain, Petit &; Diagne, 1989 and L. patersoni (Mazza, 1928), respectively, throughout their range, but these filarioids are readily differentiated from L. navonae. These well-differentiated filarial species found in Nectomys and Holochilus could indicate how isolated the populations of rodents are and could be interpreted either as: (a) an early point in the speciation processes that could be taking place in these hosts; or (b) extra support for the capture phenomenon theory of the evolution of Litomosoides. New regions, such as southern Brazil and northern Argentina, need to be studied in order to clarify these alternatives.