Typhlosyrinx -like tropical deep-water turriform gastropods (Mollusca,Gastropoda, Conoidea)

Based on radular and protoconch morphology, the genus Typhlosyrinx Thiele, 1925 has been successively classified in the subfamily Turriculinae of the family Turridae and in the subfamily Clathurellinae of the family Conidae. It is shown that the protoconch had earlier been misinterpreted, and the presence of a diagonally cancellated sculpture indicates a placement in the conid subfamily Raphitominae. Two conchologically similar genera, based on teleoconch sculpture and radular morphology are recognized: Typhlosyrinx, with axial ribbing on teleoconch spire whorls and a radula with long (250 μm) barbed teeth, and Leiosyrinx n. gen., without axial sculpture and a radula with short (<100 μm) simplified teeth. Five species (two new) of Typhlosyrinx and four species (all new) of Leiosyrinx are recognized, all at bathyal depths between 280 and 1840 m in the tropical Indo-Pacific and Panamic provinces. The two genera are not known earlier than the Pliocene, where they already occurred in deep-water assemblages.     

A new genus and species of the nudibranch family Janolidae (Mollusca; Gastropoda,Opisthobranchia) from New Zealand waters

Summary

Galeojanolus ionnae gen. et sp. nov. is described in some detail. The new genus is distinguished from the others in the family Janolidae by a peculiar helmet-like cephalic appendage, a pair of large composite oral glands, extremely inflated cerata and strongly denticulate radular teeth.     

The Hypselodoris infucata,H. obscura and H. saintvincentius species complex (Mollusca,Nudibranchia, Chromodorididae), with remarks on the genus Brachychlanis Ehrenberg, 1831

The Indo-Pacific species Hypselodoris infucata (Rüppell and Leuckart, 1830) and Hypselodoris obscura (Stimpson, 1855) have been regarded as distinct by most authors. In this paper, numerous specimens with the colour pattern described for both H. infucata and H. obscura, and collected from localities comprising the geographic range of both nominal species, have been examined and anatomically studied. All specimens from south-east Australia, the type locality of H. obscura, consistently have a very long ejaculatory portion of the vas deferens, whereas in specimens collected from other Indo-Pacific localities this portion is very short. There are no other major morphological or anatomical differences between H. infucata and H. obscura. It is not clear whether H. obscura and H. infucata are different species, but since there is at least a consistent anatomical difference between them, they are provisionally regarded as distinct. The reproductive system, radula and external morphology are extremely variable among specimens of H. infucata. Specimens from Indo-Pacific localities other than south-east Australia, even those externally similar to H. obscura, belong to H. infucata. Hypselodoris saintvincentius Burn, 1962, which has been regarded as a synonym of H. infucata, is clearly distinguishable by the external coloration, reproductive system and radular morphology. Phylogenetic evidence indicates that H. saintvincentius is the sister species of H. infucata and H. obscura. A re-examination of the holotype of the uncertain species Brachychlanis pantherina Ehrenberg, 1831 revealed that it is conspecific with Hypselodoris infucata. Therefore, the name Brachychlanis Ehrenberg, 1831, which has not been used for more than 50 years, has preference over the widely used name, Hypselodoris Stimpson, 1855. In order to preserve nomenclatural stability invalidation of the name Brachychlanis is proposed.     

A new species of Crepidula (Mollusca: Mesogastropoda: Calyptraeidae) from Chile: additional characters for the identification of eastern Pacific planar Crepidula group

A new species of Crepidula is described. It was collected together with Pagurus edwardsii Dana and Pagurus perlatus H. Milne Edwards, inhabiting the inside of empty shells of Tegula euryomphala Jones and other gastropods. The shell is low convex-oval in juveniles, low convex-oblong in males and concave-oblong elongated in females. In the adult phases the apex projects slightly at the posterior border. The sinusoidal septum is ‘V’ shaped at its centre, with a smooth sulcus in the left quarter. The osphradium has 2–13 digitiform leaflets according to phases of the life cycle. The characteristically thin, external-lateral teeth of the taenioglossate radula possess a row of denticles. In addition, evidence is given that: (1) males have a lanceolate penis with a spermatic tube; (2) the intracapsular-embryonic development starting with many embryos, occurs with a decrease at the larvae-protoconch stage, each one with an adhered-vitelline mass, and culminates with a few prehatching juveniles of 1 mm size. In the expression of the consecutive-protandric hermaphroditic sexuality, the male phase is truly separated from the female phase by a transition period at the population level. The shell and radular morphology, intracapsular development and ecological antecedents allow the proposal of Crepidula coquimbensis as a new species, and suggest a future taxonomic revision of the group based, moreover, on osphradium structure and new characters of the reproductive system, such as penis morphology.     

Bostryx tortoranus (Doering, 1879) species complex (Gastropoda: Stylommatophora: Bulimulidae), a review of taxonomy and distribution of endemic species from Argentina

Morphology of the shell, radula, jaw, anatomy and sculpture of the inner wall of the reproductive system are described and compared for three species belonging to the Bostryx tortoranus species complex. On the basis of these characters, the following changes are proposed: Bostryx martinezi (Hylton Scott, 1965) is removed from synonymy with Bostryx tortoranus (Doering, 1879) and Bulimulus (Scansicochlea) cicheroi Hylton Scott, 1967 is transferred from synonymy with B. tortoranus to synonymy with B. martinezi. As a result of these changes, the number of species of Bostryx known from Argentina has increased to 19 species. Bostryx tortoranus and B. martinezi are redescribed, also the radula and anatomy of Bostryx rudisculptus (Parodiz, 1956) are described for the first time. The main distinctive morphological characters of the three species are: the structure of the shell’s protoconch and teleoconch, radular morphology, location of the secondary ureter opening, the length of the free oviduct with respect to the vagina and the epiphallus with respect to the penis and the bursa copulatrix duct’s inner wall sculpture. Bostryx martinezi and B. rudisculptus have restricted distributions and are ecologically endemic, whereas B. tortoranus has a wide distribution and is located in different dry ecoregions.

http://zoobank.org/urn:lsid:zoobank.org:pub:A2F21A37-E0ED-454F-A63D-EEC1804D7DFA     

Redescription of Retilaskeya horrida (di Monterosato, 1874) comb. nov. and a re-evaluation of the taxonomic affinity of the genus Retilaskeya (Caenogastropoda: Triphoroidea)

The family Cerithiopsidae H. Adams and A. Adams, 1853 is distributed worldwide, and comprises around 800 extant species divided into ~40 genera. The most speciose genus within the family is Cerithiopsis Forbes and Hanley, 1850, a taxon currently used as a general receptacle rather than as a proper phylogenetic lineage. We hereby redescribe the rare species Cerithiopsis horrida di Monterosato, 1874, review its nomenclature, known material, and distribution as well as figure the entire protoconch, operculum, and radula for the first time. Our results highlight extreme differences between ‘Cerithiopsis’ horrida and the Cerithiopsis type species Cerithiopsis tubercularis (Montagu, 1803) and strong morphological and radular similarities with species belonging to the genus Retilaskeya Marshall, 1978. A wide discussion lists several taxa that might be ascribed to the same group of species, which presumably constitute a different worldwide lineage. Pending relevant molecular phylogenetic studies of the Triphoroidea Gray, 1847, for morphological conformity we suggest transferring ‘Cerithiopsis’ horrida to the genus Retilaskeya, and the same action is presumably appropriate for its possible sister species ‘Cerithiopsis’ leopardus Rolán and Gori, 2013. Finally, Retilaskeya better conforms to Newtoniellidae Korobkov, 1955 than Cerithiopsidae.     

Primno evansi sp. nov. (Amphipoda: Hyperiidea) from the eastern North Atlantic

A new species of hyperiid amphipod, Primno evansi, is described from samples collected on R.R.S. Discovery Cruise 140, August to September 1983, in the eastern North Atlantic. The genus Primno, which has a wide geographic distribution, is now represented by five species with two of these occurring in the eastern North Atlantic. Primno evansi is closest to P. brevidens.     

Ophicardelus (Mollusca,Pulmonata) in eastern Australia: how many taxa?

The common south-eastern Australian estuarine ellobiid snails belonging to Ophicardelus have been considered to be one variable taxon by some authors, and three largely sympatric species by others. This study was undertaken to determine the number of taxa present. Different types of data collected included shell shape, allozyme electrophoresis, shell and radular morphology, anatomy and geographic range. These data sets were then examined for consistent discontinuities, and the results showed that the nominal species could be distinguished by a combination of shell shape and sculpture. Individuals from each nominal species also grouped together using allozyme data, although one taxon (Ophicardelus quoyi) is sometimes paraphyletic based on these data. There are several differences in the anatomy and radular morphology that separate the three taxa. These included marked differences in the penial complex, vagina, and presence or absence of a pallial gland. The three taxa also have different geographic ranges, albeit with most of their ranges in sympatry. Based on these differences, Ophicardelus ornatus, O. quoyi and O. sulcatus should be regarded as valid species.     

Two new Pleioplana species (Platyhelminthes,Polycladida, Acotylea) from Turkey

Two new species of flatworms, Pleioplana bosphorensis sp. nov. and Pleioplana Okusi sp. nov., Acotylea, Polycladida, are described from the shallow rocky shores of the Turkish Straits System, northwestern Turkey. Both species are characterized by a prostatic vesicle of atomata-type, stylet and Lang's vesicle. Pleioplana bosphorensis possesses a body of fleshy consistency and without tentacles, with spermiducal bulbs; elongated seminal vesicle and rounded prostatic vesicle with four tubular chambers and a conical, strong, large and straight stylet. Pleioplana Okusi has a translucent body, tentacular knobs, large seminal vesicle, elongated prostatic vesicle with six tubular chambers, and a long slender slightly curved stylet.     

Revision of the genus Niwaella in China (Pisces,Cobitidae), with description of two new species

Loaches of the genus Niwaella, family Cobitidae, are distributed only in East Asia. At present only in Japan and South Korea have fishes of the genus Niwaella been found. Herein we revise the genus Niwaella in China. Son and He () transferred the species Cobitis laterimaculata to the genus Niwaella, but their specimens were not N. laterimaculata, but a new species, N. longibarba sp. n., collected from Cao'ejiang River, Huangzezhen, Chengxian County, Zhejiang Province. The new species is distinguished from N. laterimaculata by its colour pattern of a row of slightly large, and long, scattered dark brown vertical bars on the dorsolateral surface, two or three striations on the caudal fin, and long barbels and undeveloped mental lobes. In this paper we also describe another new species, N. xinjiangensis sp. n., collected from Xinjiang River, Guangfeng County, Jiangxi Province, May 1990, with diagnostic colour pattern of 17–20 large and long, dark brown vertical bars on the dorsolateral surface, a dark stripe or rounded black spots along the lateral midline and some blotches below the lateral midline; it is a large‐sized species, with shorter barbels, and longer caudal peduncle. Thus five species of the genus Niwaella are known, three are endemic to eastern China and two are endemic to either Japan or South Korea.     

Colour change in Darwin's frogs (Rhinoderma darwinii,Duméril and Bibron, 1841) (Anura: Rhinodermatidae)

In the laboratory, wild-caught male Rhinoderma darwinii frogs, but not females, changed body colour from brown to green starting with the appearance of green dorsal spots or a greenish dorsal tone on a brown body colour. After a year in captivity, most males exhibited a greenish or complete green dorsal colour, probably induced by the terrarium's swamp (green) vegetation and season.     

Morphology of thalassinidean (Crustacea: Decapoda) mouthparts and pereiopods in relation to feeding,ecology and grooming

The morphology of the mouthparts and pereiopods of three thalassinidean mudshrimps, Callianassa subterranea (Montagu), Jaxea nocturna Nardo and Upogebia stellata (Montagu) (Decapoda: Thalassinidea) are described. The distribution of setae is also described and related to function, in particular to feeding and grooming. The comparative morphology of the maxillipeds and pereiopods showed greatest differences between species and can be related to differences in feeding behaviour. Callianassa subterranea has mouthpart morphology and setation suitable for handling sediment particles and highly specialized pereiopods consistent with the digging activity of a deposit feeder. Upogebia stellata is the most densely setose of the three species and many of the appendages bear layered fringes of setae which are used to trap fine particles during suspension feeding. Jaxea nocturna appears to possess mouthpart and pereiopod setal combinations suitable for a fine sediment diet but is the least morphologically specialized species. It does not use its pereiopods in grooming behaviour. Specialized denticulate setae on the coxa of the third maxilliped may take over the gill grooming functions performed by the pereiopods of C. subterranea and U. stellata. In C. subterranea and U. stellata the feeding structures are adapted to a specific trophic mode but have features that allow other modes to be used, whilst J. nocturna is much less specialized and may represent a more primitive thalassinidean form.     

An imperfect imago? Post-mating loss of iridescent scales in Cheimas butterflies may change female from attractive to cryptic (Lepidoptera: Nymphalidae: Satyrinae)

Adults of both sexes of Cheimas opalinus (Staudinger), a Satyrinae butterfly occurring in the cloud forests of the Venezuelan Cordillera de Mérida, have simple wing colour patterns, dark brown dorsa marked by one conspicuous element, large greenish-blue patches in the discal area of the hind wing. It was observed that in young, freshly emerged females these patches are frequently absent. They fade away and eventually disappear during mating and nuptial flights when brushed out by lateral movements of the male’s hind wing put between folded female hind wings. The falling off of the scales is made easy because they do not adhere to the wing as firmly as brown background scales due to their particular folded extremities. We speculate that this process is related to the fitness of the females. Prior to mating, blue-green patches are advantageous because they attract the attention of the opposite sex and enhance the chances of successful mating. After mating they lose their sexual role. Females without the blue-green patches become cryptic. Thus, they are less apparent not only for the males, which helps them avoid sexual harassment, but also for potential bird predators. Additionally, the loss of blue reflecting scales may speed up the warming up of the abdomen and egg maturation. In the males, positive role of the patches (signalling), and negative (bird attraction), is balanced during their entire life span, and they fade gradually due to regular usage of wings scaling in flight. Our hypothesis is supported by morphological, optical, experimental and statistical analysis in which we used 509 individuals of both sexes. A similar ratio of young (with undamaged wing) females with or without blue patch was recorded, whereas in the males no individuals without any trace of blue patch were reported, and a correlation of age (wing damage) and gradual fading off of the patch was demonstrated. Such an adaptation involving an active change of the appearance of adults, i.e. colour patterns related to sexual selection, has not been reported previously in Lepidoptera.     

Structure and functioning of the gut in the Bullomorpha (Opisthobranchia)

Summary

A study of the form and functioning of Aglaja cylindrica and Aglaja aureopunctata. In this family the radula and gizzard plates are absent. In Aglaja cylindrica the buccal bulb has enlarged to form a pump used to suck in polychaete and nemertine worms. In Aglaja aureopunctata the buccal bulb can partially evert, enabling the species to ingest shelled opisthobranchs. In both species an oesophageal crop fulfils the role of the reduced stomach. A short review of the histology of the digestive gland is also included.     

A redescription of the type specimen of Crotonia (= Acronothrus) obtecta (O. Pickard-Cambridge, 1875), (Acari,Cryptostigmata) and a discussion of its taxonomic relationships

Summary

The holotype of Crotonia (= Westwoodia) obtecta (O. Pickard-Cambridge, 1875) has been cleaned and is redescribed. Study indicates that Crotonia Thorell, 1876 is a senior synonym of Acronothrus Berlese, 1916, and that the family Crotoniidae Thorell, 1876 is a senior synonym of the Holonothridae Wallwork, 1963