Larval and early post-larval shell of three deep-sea Scaphopoda (Mollusca) from the southwest Atlantic

• Published in: Molluscan research Vol. 39; no. 1; pp. 35 - 43
• Main Authors: Vilela, Priscila Magalhães Silva, de Souza, Leonardo Santos, Caetano, Carlos Henrique Soares
• Format: Journal Article
• Language: English
• Published: Sydney Taylor & Francis 02.01.2019; Taylor & Francis Ltd
• Subjects: benthos; Campos basin; Deep sea; Deep sea environments; Deep water; Dentaliida; Dentaliidae; Discriminant analysis; Entalimorpha; Entalinidae; Expeditions; Gadilida; Mollusks; Morphometry; Multiship expeditions; praetubulus; protoconch; Regions; Shells; Taxa
• ISSN: 1323-5818; 1448-6067
• DOI: 10.1080/13235818.2018.1513896

The larval shells of Antalis circumcincta (Watson, 1879) (order Dentaliida), Pertusiconcha callithrix (Dall, 1889) (order Gadilida) and of an undetermined species of uncertain systematic position are described. The material studied comprises mainly samples from deep waters, collected by expeditions along the southeast coast of Brazil. The larval shell of the three taxa matches other types previously described in the literature. Antalis circumcincta and P. callithrix have four regions (protoconch A, protoconch B, teleoconch A, teleoconch B), but differ in dimensions and sculpture from each other, while the undetermined species has three regions (protoconch A, protoconch B, teleoconch B). A morphometric approach combined with a discriminant analysis also indicates that the three taxa are significantly distinct. This study confirms patterns of larval shells at the taxonomic rank of orders but other supraspecific patterns remain uncertain.