Australian freshwater assimineids,with a synopsis of the Recent genus-group taxa of the Assimineidae (Mollusca: Caenogastropoda: Rissooidea)

The morphology of the two species of Australian freshwater assimineids is described in detail. A new genus and species of Assimineinae, Aviassiminea palitans, is named from freshwater springs in north Western Australia and the Northern Territory. Austroassiminea letha Solem et al., 1982 from coastal springs in south Western Australia is also described and the original anatomical account is corrected in several important details. This taxon is shown to be a member of the Omphalotropidinae and is the only other non-marine assimineid known from Australia. All of the described assimineid genus-group taxa are listed in an appendix, with an assessment of their status, and their known diagnostic characters.     

An unusual,flagellum-bearing hydrobiid snail (Gastropoda: Rissooidea: Hydrobiidae) from Greece,with descriptions of a new genus and a new species

A new genus and a new species of Hydrobiidae, Agrafia wiktori sp. nov., from the Agrafa Mountains, northern Greece, are described based on the shell, protoconch, radula and male and female reproductive organs. In the protoconch sculpture and female reproductive organs A. wiktori resembles a typical member of Hydrobiidae Sadlerianinae, but the penis with tubular penial gland terminating within the flagellum and extending into the cephalic haemocoele has not been found in any other representative of Hydrobiidae. Instead, it is comparable with the penes and tubular penial glands of some non-hydrobiid Rissooidea (Bithyniidae, Bythinellidae, Amnicolidae, Emmericidae). Analysis of partial sequences of 18S ribosomal DNA and cytochrome oxidase subunit I mitochondrial DNA in A. wiktori place it in Hydrobiidae Sadlerianinae. The evolution of the bifid penis and tubular penial gland is discussed.     

On the taxonomic status of the highly endangered Ponto-Caspian gastropod genus Caspia (Gastropoda: Hydrobiidae: Caspiinae)

Caspia is an endemic Ponto-Caspian Basin genus of hydrobiid gastropods. Around a dozen nominal species of Caspia have been described to inhabit the Caspian Sea while four species occupy a restricted zone in the lower part of the rivers flowing into the Black Sea and the Sea of Azov. Scanning electron microscopic study of the protoconch and radula morphology of two Caspia species from the Azov–Black Sea Basin allows re-evaluation of the taxonomic rank and attribution of the genus. The adult shell geometry and characters of ornamentation do not enable clear demarcation of these species of Caspia but the protoconch parameters do allow their differentiation. Available morphological data on Caspia and the related genus Caspiohydrobia are interpreted here as confirmation of the subfamilial rank of Caspiinae in the family Hydrobiidae, in contrast to the previous affiliation of this group with Pyrgulidae.     

Predation on invasive land gastropods by a Neotropical land planarian

Studies on the predatory behaviour of land planarians have focused mainly on established invasive species, while the feeding habits of non-invasive planarians are poorly understood. We analyse the predatory behaviour of Obama ladislavii, a land planarian native to southern Brazil that is common in both natural and human-disturbed areas. Observations were performed in the laboratory. Several groups of invertebrates were offered as possible prey and interactions between these invertebrates and planarians were recorded. Obama ladislavii fed on the introduced land gastropods Bradybaena similaris, Helix aspersa and Deroceras laeve, ignoring other invertebrates. Once potential prey were identified, we tested the ability of O. ladislavii to recognize and follow slime trails, and demonstrated the planarian’s ability to follow chemical trails from prey in the environment. The consumption of exotic species indicates a flexible, generalist diet that is consistent with the ability of O. ladislavii to adapt to environments altered by human activities. Thus, this species may become invasive if introduced outside of its original distribution, but it also has the potential to be used in biological control programs for pest management in its native range.     

Revision of the genus Caucasocressa from the eastern Pontic Region (Gastropoda: Hygromiidae)

The genus Caucasocressa is revised. Ten Caucasocressa species are known from north-east Turkey and south-west Georgia. Five new species are described. For every taxon the shell is described and illustrated and the variability of the genitalia (as far as known) is shown. All synonyms are listed. The distribution is summarized and all locality records are listed. The distribution of the species is illustrated on a UTM grid-map.     

Revision of the American Pupisoma species (Gastropoda: Pupilloidea)

The American species of Pupisoma Stoliczka (Gastropoda: Pupilloidea) are revised. Five species are recognized. Pupisoma puella Hylton Scott has been synonymized with P. dioscoricola (C. B. Adams). This species occurs from southern USA through the Caribbean and Central America to the Galapagos Islands and to southern Brazil and northern Argentina. Pupisoma galapagorum Pilsbry, P. bailyi Pilsbry, and P. latens Hylton Scott have been synonymized with P. comicolense H. B. Baker. This species is distributed from Mexico to the Galapagos Islands, southern Brazil, and northern Argentina. Pupisoma costulata sp. n. from Andean forests in Colombia is described as new. The range of P. macneilli (Clapp) extends from southern USA through the Caribbean and Central America to southern Brazil and northern Argentina. A neotype has been designated for P. mediamericanum Pilsbry. Pupisoma michoacanense Pilsbry is a synonym of this species. This species occurs from Mexico to Colombia and on Jamaica.     

Cercaria hastata sp. nov. (Digenea: Trematoda) in Bullia digitalis,a sandy beach surfing whelk from the Western Cape coast of South Africa: epidemiology and sex linked phenomena

Morphometric and sex linked phenomena in male Bullia digitalis, from the Western Cape coast of South Africa, are related to infection with a digenean microphallid larva described here for the first time and named Cercaria hastata. Penis shedding in Bullia is not uncommon. Most of the stumps are found on infected whelks, and this is probably due to parasitic inhibition of an otherwise rapid regeneration. The infection also abolishes sperm production. Stumps were never seen on sperm producing males, all of which have large penes, and in non-infected males, shedding occurs only in non-producers. In large non-infected Bullia, those which have underdeveloped penes and are non-producers of sperm may be transient intersexes. This is supported by the exhibition of protandry indicators such as brooding, nonsize preferential mate selection and gregariousness. Infection prevalence is size dependent, large whelks being more commonly infected; but parasitic gigantism is thought unlikely as Bullia is iteroparous.     

A new species of dorid nudibranch of the genus Taringa Marcus, 1955 (Mollusca: Opisthobranchia) from the southern Iberian peninsula,with remarks on world species of the genus

A new dorid nudibranch from the southern Iberian peninsula is described. Taringa tarifaensis n. sp. is subtidal and has been found under stones. A comparison between T. tarifaensis and the other known species of the genus is presented, as well as some remarks on the taxonomic status of the genus Taringa.     

Revision of ‘Horatia’ snails (Mollusca: Gastropoda: Hydrobiidae sensu lato) from South Caucasus with description of two new genera

Four nominal species of the genus Horatia Bourguignat, 1887 were described by Russian authors from Caucasian caves (H. borutzkii Shadin, 1932, H. birsteini Starobogatov, 1962, H. ljovushkini Starobogatov, 1962 and H. sokolovi Starobogatov, 1962). Hitherto all the species were known from type series (presented by empty shells) only. Examination of newly obtained samples from the caves of South Caucasus has shown that the four species actually do not belong to the genus Horatia due to obvious differences in the morphology of the copulatory organs between H. klecakiana Bourguignat, 1887 (the type species of this genus) and the Caucasian snails. Moreover, statistical analysis of conchological variation has revealed that the species H. birsteini, H. ljovushkini, and H. sokolovi are conspecific. Two genera are described: Pontohoratia (includes P. birsteini and P. smyri sp. nov.) and Motsametia (with the single species M. borutzkii comb. nov.). The two genera can be distinguished on the basis of the structure of their copulatory organs. The distribution and ecology of the Caucasian Horatia-like mollusks are briefly outlined.

http://zoobank.org/urn:lsid:zoobank.org:pub:4EDFB2AE-CB1D-4113-8CC7-3A1BBB46D838     

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.     

A new species of Thais (Mollusca: Neogastropoda: Muricidae) with direct development from northwestern Australia

Thais wutingi, a new species of Muricidae, is described from rocky and mangrove shores in the vicinity of Darwin, northern Australia. It is relatively common where it occurs but the species may have previously been mistaken for T. gradata (Jonas) or T. javanica (Philippi). The new species differs from the latter two species in having a penis with a narrow groove along the greater curvature of the penial base. The larvae of T. wutingi undergo direct development, hatching from egg capsules as crawling juveniles, in contrast to the majority of Thais (s.l.) species found in the tropics which have planktotrophic development. Its mode of development may explain the relatively restricted geographical distribution of this species, which is confined to the north and northwestern coasts of Australia.     

The Tanaidacea (Crustacea,Peracarida) of the North-East Atlantic: the shelf and bathyal Paratyphlotanais of the ‘Atlantic Margin’

Increasing oil-exploration activity and associated ecological surveying west of the Shetlands is leading to the discovery of many poorly known or undescribed tanaidaceans. Three species of the typhlotanaid genus Paratyphlotanais Kudinova-Pasternak and Pasternak, 1978 Kudinova-Pasternak R. K Pasternak F. A 1978 Deep sea Tanaidacea collected from the Caribbean Sea and Puerto Rico trench during the 16th cruise of RV ‘Akademik Kurchatov’ and the resemblance between the fauna of deep-sea Tanaidacea of the Caribbean region and the Pacific Trudy Instituta Okeanologiii. Akademiya Nauk SSSR, 113, 115–135 (in Russian)  [Google Scholar] have been recorded from shelf and bathyal depths between Iceland, the Faroe Islands and the western margin of the British Isles. Two, P. gracilipes (Hansen) and P. microcheles (G. O. Sars), formerly belonging to the genus Typhlotanais, are redescribed and a new species is described. A key to their identification is included. Inhabiting largely discrete zoogeographic areas, these species help define regional macrofaunal associations.     

The genus Lilloiconcha in Colombia (Gastropoda: Charopidae)

The name Lilloiconcha Weyrauch, 1965 Weyrauch, W. K. 1965. Neue und verkannte Endodontiden aus Südamerika.. Archiv für Molluskenkunde, 94: 121–134.  [Google Scholar] is used tentatively for South American charopids with a reduced penis, a barely differentiated epiphallus and multicuspid marginal radular teeth. Trochogyra Weyrauch, 1965 Weyrauch, W. K. 1965. Neue und verkannte Endodontiden aus Südamerika.. Archiv für Molluskenkunde, 94: 121–134.  [Google Scholar] is considered to be a synonym of Lilloiconcha. In addition to the widespread Lilloiconcha gordurasensis (Thiele, 1927 Thiele, J. 1927. Über einige brasilianische Landschnecken.. Abhandlungen der Senckenbergischen Naturforschenden Gesellschaft, 40: 307–329. Plate 26 [Google Scholar]), Lilloiconcha costulata new species and Lilloiconcha laevigata new species are described from the Cordillera Oriental in Colombia. The distribution of Lilloiconcha gordurasensis in South America is summarized.     

Exploitation of Cornucopina tuba (Bryozoa: Cheilostomata) by Aetea curta (Bryozoa: Cheilostomata)

Distal portions of zooids of uniserial, encrusting Aetea colonies curve abruptly away from the encrusted substratum. This characteristic, plus highly directional growth capability, enabled A. curta infesting an erect Cornucopina tuba colony to position its feeding structures consistently above the host colony, perhaps as a rheophilic growth response of individual zooids to feeding currents set up by the host.     

The pars jugularis and the intrarelationships of cichlid fishes (Labroidei,Teleostei)

The anatomy and morphology of the pars jugularis skull region in cichlid fishes has been used recently, and for the first time, as a crucial character to establish intrafamilial phylogenies for these African, Malagasian and Neotropical freshwater teleosts. The new phylogeny cuts across relationships postulated in previous schemes, and suggests novel and geographically disjunct intrafamilial groups. It does not, however, seem tenable.

A detailed investigation of the cichlid pars jugularis, involving many more taxa and wider outgroup comparisons than were used to formulate the new classification, is described here. Apart from clarifying certain misconceptions about the anatomy of the pars jugularis in the Cichlidae, this study shows, at least in that family, that the character is valueless as an indicator of higher level intrafamilial relationships, and is of very limited value for establishing phyletic affinities at lower levels.

Other osteological features used in the new classification were also tested on a larger scale. None of these, either, refutes the two other and recent hypotheses-one of intrarelationships amongst Neotropical cichlids and the second for the family as a whole.