Comparative anatomy of the fasciolariids <em>Pustulatirus ogum</em> and <em>Hemipolygona beckyae</em> from Brazil (Gastropoda: Buccinoidea: Peristerniinae)

Abstract

Summary:The Brazilian species Pustulatirus ogum and Hemipolygona beckyae were examined, and certain morphological characters were described. Both species were originally assigned to the genus Latirus, considered as a heterogeneous complex. The radulae of both species are like that which characterizes Latirus, in which the innermost cusp of the rachidian tooth is well developed but always smaller than the other cusps. This feature differs from Leucozonia, in which this cusp is reduced or absent. The penis tapers terminally, and the tapered part may be long (more than half the total penis length), as in H. beckyae, or very short (less than half the total penis length), as in P. ogum. The anatomical data observed in both species are discussed under the framework of fasciolariid systematics and they appear to be widespread among other fasciolariid species. For this reason, to date, the soft-part features here provided and those known from previously studied species of Latirus are not useful for delineating precise generic diagnoses.Keywords: morphology; Caenogastropoda; Fasciolariidae; Latirus; western Atlantic. Anatomía comparada de los fascioláridosPustulatirus ogum y Hemipolygona beckyae de Brasil (Gastropoda: Buccinoidea: Peristerniinae) Resumen: Se describe la morfología y anatomía de las especies brasileñas Pustulatirus ogum y Hemipolygona beckyae. Ambas especies han sido tradicionalmente asignadas al género Latirus, que en la actualidad se considera que agrupa a un conjunto heterogéneo de especies. Las rádulas de ambas especies son como la que caracteriza a Latirus, con la cúspide más interna del diente raquídeo bien desarrollada y siempre menor que las otras cúspides. Esta característica difiere de la que presentan las especies del género Leucozonia, en las que esta cúspide está reducida o ausente. El pene se estrecha en su parte terminal, y la parte cónica puede ser larga (más de la mitad de la longitud total del pene), como en H. beckyae, o muy corta (menos de la mitad de la longitud total del pene), como en P. ogum. Los caracteres morfológicos observados en ambas especies se discuten en el marco de la sistemática de los Fasciolariidae y parecen estar ampliamente distribuidos en otras especies de fascioláridos. Por ello, hasta la fecha, las características de las partes blandas del animal aquí descritas y las conocidas previamente de otras especies de Latirus no se consideran de utilidad para la diagnosis de los géneros en esta familia.

Morphological comparison between Doryteuthis pleii and D. sanpaulensis (Cephalopoda, Myopsida, Loliginidae) from Brazil

“…Nowadays, detailed studies on squid anatomy are scarce, even though morphological data have proved to be very useful in producing phylogenetic hypotheses and defining relationships within mollusk groups (e.g., Simone, 2011;Couto et al, 2015;Dornellas & Simone, 2015). There are more recent papers about molecular analyses than morphological studies.…”

A Phylogenetic Analysis of Fasciolariidae (Gastropoda: Buccinoidea)

“…Simone (2011) pointed to the loss of accessory pair of protractor muscles of odontophore (m14) in Neogastropoda; in the present analysis it was observed that the origin of the m11 muscles occur posteriorly in the odontophore cartilages, as opposed to inserted in the haemocoelic wall. This odontophore type occurs in all neogastropods present in the literature (e.g., Simone et al, 2009;Simone & Pastorino, 2014;Couto et al, 2015a;2015b).…”

“…Terminology for the anatomical study followed traditional studies (e.g., Simone, 2005Simone, , 2007, and modified by the author (e.g., Couto et al, 2015a;2015b). Imaging material was edited in Corel Photo-Paint X8 and Adobe Illustrator CC 2015.…”

“…Unlike previous opercula with a terminal nucleus, the nucleus of this type of operculum is located in lateral, hook-like extension (but see character discussion for more on this). Snyder & Callomon (2005) stated the presence of a slightly hooked terminal nucleus for three Fusolatirus species, and Couto et al (2015a;2015b) for several peristerniine and fasciolariine species from Brazil.…”

“…Turrilatirus turritus (Gmelin, 1791), Pustulatirus mediamericanus (Hertlein & Strong, 1951), Latirus polygonus (Gmelin, 1791), Peristernia nassatula (Lamarck, 1822), Peristernia ustulata (Reeve, 1847), Opeatostoma pseudodon (Burrow, 1815), Fusinus tenerifensis Hadorn &Rolán, 1999 andTarantinae lignaria (Linnaeus, 1758). Marcus & Marcus (1962) made detailed anatomical descriptions of Leucozonia nassa (Gmelin, 1791) from Brazil, while studied the Brazilian Leucozonia species: L. nassa (Gmelin, 1791), L. ocellata (Gmelin, 1791) and L. ponderosa . Couto et al (2015a…”