Semicytherura Wagner: its inner lamella and its close allies

WHATLEY R. C.; CUSMINSKY, G

JOURNAL OF MICROPALEONTOLOGY

The Micropaleontological Society

Lugar: Londres; Año: 2010 vol. 29 p. 1 - 4

0262-821X

ABSTRACT – The genus SemicytheruraWagner differs from all other members of the Cytherurinae in thenature and course of its inner margin/line of concrescence. The inner lamella is very wide anteriorly, whileposteriorly the inner margin extends anteriorly almost to the position of the closing muscles. However,two species examined by the authors, Semicytherura clavata (Brady, 1880) and Semicytherura contrariaZhao & Whatley, 1989, from the SW Atlantic and SE Asia respectively are shown to exhibit thischaracteristic feature only in the male. In the female of both these species, while the anterior inner lamellais identical to that of the male, posteriorly their inner margins parallel the posterior margin. Similarsex-linkage was show in the genus Angulicytherura which is probably closer to Cytherura thanSemicytherura, with a narrow and vestibulate inner lamella. J. Micropalaeontol. 29(1): 1–5, April 2010.