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Insemination by a kiss? Interactive 3D-microanatomy, biology and systematics of the mesopsammic cephalaspidean sea slug Pluscula cuica Marcus, 1953 from Brazil Gastropoda Euopisthobranchia Philinoglossidae


, : Insemination by a kiss? Interactive 3D-microanatomy, biology and systematics of the mesopsammic cephalaspidean sea slug Pluscula cuica Marcus, 1953 from Brazil Gastropoda Euopisthobranchia Philinoglossidae. Organisms Diversity & Evolution 13(1): 33-54

Increasing molecular evidence suggests that the phylogeny of euthyneuran gastropods differs greatly from centenary textbook concepts. The presence, homology and evolution of characters in major subgroups thus need to be reinvestigated. Traditionally basal opisthobranch Cephalaspidea ( head-shield snails and slugs ) were pruned to a new taxon concept, with benthic euopisthobranch and tentacle-bearing cephalaspidean lineages basal to burrowing, head-shield bearing philinoidean species. Among the latter, mesopsammic microslug lineages evolved at least twice. Herein we explore in 3D microanatomical detail the putatively basal philinoglossan Pluscula cuica (Marcus, Boletim da Faculdade de Filosofia, Ci ncias e Letras. Universidade de S o Paulo 164:165 23, 1953a) from its type locality in Brazil. The species possesses several accessory ganglia and a reduced posterior mantle cavity that retains some putative shell-building tissue and an osphradium. The hermaphroditic, monaulic genital system opens in a posterior position; it retains a bursa copulatrix but lacks a distinct receptaculum seminis. Autosperm is transferred to the cephalic copulatory organ via an external sperm groove, not through the hemocoel, as suggested in the original description. The penis opens through the oral tube, sperm is transferred by a kiss . A conspicuous yellow gland is discussed as a modified Blochmann s gland. Retaining several putative symplesiomorphies with philinoids, Pluscula is discussed as the most basal offshoot in meiofaunal Philinoglossidae. However, the supposed primitiveness of the fused rather than separate cerebropleural ganglia and the triganglionate rather than pentaganglionate visceral nerve cord was based on misobservations. Higher categories such as Philinoglossacea for Philinoglossidae, and a separate family Plusculidae for P. cuica are no longer warranted. Inner cephalaspidean relationships and a scenario of more or less successive philinoglossid adaptation to meiofaunal environments should be investigated by molecular studies with more comprehensive taxon sampling.

US$19.90

DOI: 10.1007/s13127-012-0093-3


Other references

Butera, E., 1993: 1993 educational resource directory. Anna Journal 20(4): 475-499

Alemi, F., 1992: Improving the accuracy of severity indexes: exceptions to the rules. This study explores the difference between additive and non-additive indexes in measuring the severity of myocardial infarction. It shows, as an example, the fallacy of adding severity scores in a straightforward manner. An additive severity index...

Anonymous, 1982: Symposium on pediatric nephrology. Pediatric Clinics of North America 29(4): 775-1054

Basu, A.; Wexner, S.D., 2002: Perianal Crohn's Disease. Perianal Crohn's disease usually is associated with involvement of another primary site of Crohn's disease. However, there is conflicting evidence on the relationship between proximal disease activity and perianal symptoms. Therefore, al...

Gill, R.S.; Sandhu, G.S.; Dhooria, M.S., 1988: Studies on the pest and predatory status of mite Parasitus consanguineus Oudemans & Voigts (Parasitidae: Mesostigmata: Acari) occurring on mushrooms in Punjab. Among 3 species of mite found on mushrooms on a farm in the Punjab, none was found to be a pest and Parasitus consanguineus was the most common. P. consanguineus was found to feed on eggs and larvae of the sciarid Bradysia tritici, larvae of the p...

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Bonomo, R.P.; Pedotti, S.; Vecchio, G.; Rizzarelli, E., 1996: Molecular Recognition of Amino Acids by Copper(II) Complexes of 6(A),6(X)-Diamino-6(A),6(X)-dideoxy-beta-cyclodextrin (X = B, C, D). The three regioisomers of beta-cyclodextrin 6-difunctionalized with NH(2) groups (6(A),6(X)-diamino-6(A),6(X)-dideoxy-beta-cyclodextrin, A,X-CDNH(2), X = B, C, or D) were synthesized. Their binary and ternary copper(II) complexes with amino acids...

Hicks, G.R.F., 1977: Species composition and zoo geography of marine phytal harpacticoid copepods from cook strait and their contribution to total phytal meio fauna. A quantitative seasonal investigation of the harpacticoid copepods present in the aufwuchs assemblages of 6 marine macrophytes [Enteromorpha intestinalis, Corallina officinalis, Zonaria turneriana, Xiphophora chondrophylla var. maxima, Pterocladia...

Ruffie, J.; Larrouy, G.; Vergnes, H., 1966: Comparative hematology of Amerindian populations in Bolivia adaptative phenomena French Society of Hematology 21 February 1966. Nouv Rev Franc Hematol 6(4): 544-552