Document of bibliographic reference 405144

BibliographicReference record

Type

Bibliographic resource

Type of document

Journal article

BibLvlCode

AS

Title

Redescription of Otostomus signatus (Spix, 1827) (Gastropoda: Bulimulidae) and systematic implications for the genus

Abstract

Otostomus is a monotypic and poorly known genus Bulimulidae genus. Only parts of the reproductive system and hard parts are known for Otostomus signatus. The present study goals are, first, to redescribe O. signatus through a detailed investigation of shell features, including microornamentation and ultrastruc-ture, radula and jaw, and detailed anatomical data of its pallial cavity and associated organs, digestive, reproductive, and nervous systems. We also compare the morphology of the species with closely related bulimulids to assess if the phylogenetic relationships recently proposed in a molecular study are supported by morphology. Otostomus signatus is characterized by a conical shell sculptured by thick growth lines, with a truncate-ovate aperture, expanded peristome with three teeth, odontophore retractor muscle ramifying two times, the first in two almost symmetrical muscles, and the second in 4-5 closely attached pack of fibers, intestinal loop absent, imbricated radula, radular formula (9-(31)-1-(31)-9), ovotestis with several thin, tightly squeezed, digitiform ramifications leading to a compact seamless irregular shape, almost symmetrical nervous ring, cerebral ganglia completely fused, without commissure, posterior gan-glia completely fused, single large statocyst inside the posterior ganglia. Otostomus signatus shares more similarities in both hard and soft parts with Cochlorina than with Bulimulus, supporting recent molecular phylogenies.

Bibliographic citation

La Pasta, A.; Klautau, M.; Dilnei de Castro Oliveira, C. (2024). Redescription of Otostomus signatus (Spix, 1827) (Gastropoda: Bulimulidae) and systematic implications for the genus. The Nautilus 138(2): 35-44

Is peer reviewed

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