Bastian Brenzinger

From EESwiki

Microanatomical 3D-modelling, comparative ultrastructure and evolution of interstitial gastropods

Gastropods are one of the most diverse animal clades and have colonized almost every conceivable ecological niche worldwide. Miniaturized members of several groups are found living between sand grains - the so-called marine 'interstitial' or mesopsammic environment. Next to their reduced body-size these animals commonly show convergent evolutionary tendencies towards elongation of the body and the loss of a shell, tentacles, body coloration and eyes. The mesopsammic species tend to group together in morphology-based phylogenies, however, most species are difficult to obtain and have hence often been examined only inadequately; many original descriptions have been shown to be highly inaccurate or lacking in data needed for modern synapomorphy-based studies.

My task is to study material of several taxa of interstitial Opisthobranchia, a rather ill-defined but historically important group of highly developed marine gastropods. I will examine the minute specimens using electron microscopy (SEM/TEM) and computer-based 3D reconstruction from series of semithin histological sections. My aim is to establish a solid framework on microanatomy - such as of the taxonomically relevant central nervous and reproductive systems - which can be used for future studies in order to properly place the so far problematic taxa in the phylogenetic system of higher Gastropoda.

Much of the material and know-how needed is already present and well-established with our group at the Zoological State Collection in Munich, where my supervisor will be PD Dr. Michael Schrödl, an international expert on the systematics and evolution of basal molluscan taxa and opisthobranchs.

Supervisor: Michael Schrödl