A study of the ontogeny of the Thaumatocyprididae revealed that most species in the family have six juvenile growth stages. Each growth stage is described and illustrated. A table is presented for the identification of growth stages by using the number of claws on the caudal furca. Keys are presented for the identification of growth stages of Thaumatoconcha radiata and, also, for the identification of genera and species of the Thaumatocyprididae. A phylogeny is derived for the higher taxa of Ostracoda using the Hennigian system. In this phylogeny the suborders Cladocopina and Halocypridina are referred to a new order Halocyprida. The following new taxa are described and illustrated: Thaumatomma piscifrons, new genus, new species, from the Permian of Idhra, Greece, Danielopolina carolynae, new genus, new species, from the South Atlantic Ocean, and Thaumatoconcha radiata, new genus, new species, T. caraionae, new species, T. elongata, new species, T. hessleri, new species, T. polythrix, new species, T. punctata, new species, T. sandersi, new species, T. tuberculata, new species, and Thaumatoconcha species A, from the North Atlantic, South Atlantic, and South Pacific Oceans, and from within the Antarctic Convergence. All species are referred to the ostracode family Thaumatocyprididae (superorder Myodocopa). Supplementary descriptions and illustrations are presented of all previously described living and fossil genera and species of Thaumatocyprididae and some genera and species of the Paleozoic superfamily Entomoconchacea. It is hypothesized that during the Jurassic period, representatives of the Thaumatocyprididae lived on the continental shelves of what is now Europe; then, after the Jurassic, the group migrated down the continental slope in response to competitive pressures. Their descendants survive today in bathyal and abyssal depths of the world's oceans and, in one instance, in a marine cave in Cuba. OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded in the Institution's annual report, Smithsonian Year. SERIES COVER DESIGN: The coral Montastrea cavernosa (Linnaeus).

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Kornicker, L.S. 1998 09 15: Homology of Holocene ostracode biramous appendages with those of other crustaceans: the protopod, epipod, exopod and endopod. Lethaia, Val. 31, pp. 251-265. Oslo. ISSN 0024-1164. Unambiguously biramous appendages with a proximal precoxa, well-defined coxa and basis, setose plate-like epipod originating on the precoxa, and both an endopod and exopod attached to the terminal end of the basis are described from several living Ostracoda of the order Halocyprida (Myodocopa). These limbs are proposed as the best choice for comparison of ostracode limbs with those of other crustaceans and fossil arthropods with preserved limbs, such as the Cambrian superficially ostracode-like Kunmingella and Hesslandona. The 2nd maxilla of Metapolycope (Cladocopina) and 1st trunk limb of Spelaeoecia, Deeveya and Thaumatoconcha (all Halocypridina) are illustrated, and clear homologies are shown between the parts of these limbs and those of some general crustacean models as well as some of the remarkable crustacean S.S. Orsten fossils. No living ostracodes exhibit only primitive morphology; all have at least some (usually many) derived characters. Few have the probably primitive attribute of trunk segmentation (two genera of halocyprid Myodocopa, one order plus one genus of Podocopa, and the problematic Manawa); unambiguously biramous limbs are limited to a few halocyprids. Homologies between podocopid limbs and those of the illustrated primitive myodocopid limbs are tentatively suggested. A setose plate-like extension, often attached basally to a podocopid protopod, is probably homologous to the myodocopid epipod, which was present at least as early as the Triassic. Somewhat more distal, less setose, and plate-like extensions, present on some podocopid limbs (e.g., mandible), may be homologous instead to the exopod (clearly present on myodocopid mandibles). The coxa (or precoxa) is by definition the most basal part of the limb. A molar-like tooth is present proximally on the mandibular protopod of many ostracodes; it is the coxal endite and projects medially from the coxa (or proximal protopod). The Ostracoda is probably a monophyletic crustacean group composed of Myodocopa and Podocopa. All have a unique juvenile (not a larva) initiallywith three or more limbs. Except that juveniles lack some setae and limbs, they are morphologially similar to the adult. Thus the following suite of characters in all instars may be considered a synapomorphy uniting all Ostracoda: (1) Each pair of limbs is uniquely different from the others. (2) The whole body is completely enclosed within a bivalved carapace that lacks growth lines. (3) No more than nine pairs of limbs are present in any instar..(4) The body shows little or no segmentation, with no more than ten dorsally defined trunk segments. No other crustaceans have this suite of characters. A probable synapomorphy uniting the Podocopa is a 2nd antenna with exopod reduced relative to the endopod. OOstracoda, Myodocopa, Crustacea, Podocopa, homology, morphology. Anne ...

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