title: On the Evolutionary Biology ofElpidiumOstracods (Limnocytheridae, Timiriaseviinae): A Proposal for Pluridisciplinary Studies.
abstract: The present essay reviews the history of the research on Elpidium ostracods (Timiriaseviinae), a group exclusively known to live in micro-aquaria of phytotelmata from Neotropical bromeliaceans. A new species,E. martensin. sp., is described and aspects dealing with functional morphology and taxonomy of the genus are presented. Related to these topics an evolutionary hypothesis and a programme of pluridisciplinary research are proposed. This should allow further improvement of our knowledge on the origin and evolution of the subfamily Timiriaseviinae, one of the most diverse cytheroid ostracod groups in inland waters since the beginning of the Mesozoic. Specifically, the following aspects are treated in-depth in the essay: (1) morphologic traits of the valves, useful for characterisation of Timiriaseviinae taxa; (2) the reversal of the valve overlap and hinge elements; (3) the diverse development of the posterior half of the female carapace, a quasi-independent morphological trait; (4) the morphological shapes of the male copulatory process; (5) the functional significance of the antero-ventral segment of the valve selvage for the life ofElpidiumostracods in the micro-aquaria of the bromeliaceans; (6) the necessary improvement of comparative descriptions of the limbs-chaetotaxy for Timiriaseviinae.
authors.affiliation: Institute of Earth Sciences (Geology and Palaeontology) Karl-Franzens-Universität Graz, Heinrichstrasse 26, A-8010 Graz, Austria.
authors.forename: Dan L
authors.initials: DL
authors.lastname: Danielopol
authors.affiliation: Instituto de Geociências - UnB, Laboratório de Micropaleontologia, ICC - Ala Central, Subsolo ASS339/10, Campus Universitário Darcv Ribeiro, Asa Norte, Brasília - DF, CEP 70910-900, Brazil.
authors.forename: Ricardo L
authors.initials: RL
authors.lastname: Pinto
authors.affiliation: Universalmuseum Joanneum (Geology and Palaeontology) Weinzöttlstrasse 16, A-8045, Graz, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Gross
authors.affiliation: Instituto de Geociências - UnB, Laboratório de Micropaleontologia, ICC - Ala Central, Subsolo ASS339/10, Campus Universitário Darcv Ribeiro, Asa Norte, Brasília - DF, CEP 70910-900, Brazil.
authors.forename: Julia
authors.initials: J
authors.lastname: Da Silva Pereira
authors.affiliation: Institute of Zoology, University of Salzburg, Hellbrunnerstr. 34, Salzburg 5020, Austria, (address valid for 1993; present address unknown).
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Riedl
keywords: Elpidium; Non-marine Ostracoda; Timiriaseviinae; evolutionary hypothesis; functional morphology; prospects for pluridisciplinary research; taxonomy