Stenocypris bolieki, A New Freshwater Ostracod from Florida and a New Record of Distribution for the Genus

Abstract

A new species of the ostracod genus Stenocypris from Leon County, Florida, is described. This apparently is the first record of the genus from the United States. A key to the known North American species of the genus is included. The generic diagnosis for Stenocypris is emended, and it is suggested that Stenocypris (Baird 1859) be designated as type species. Sars (1889) established the genus Stenocypris to accommodate certain species of the all inclusive genus Cypris. He designated Stenocypris maleolmsoni (Brady 1886) = Cypris Baird 1859 as the genotype. Baird's specific name cylindrica is older than and should take priority over the latter. The author suggests that the generotype is Stenocypris (Baird 1859) Sars 1889. Genus Stenocypris Sars 1889 Valves elongate, narrow, reniform; greatest height less than onehalf the length; ventral margin distinctly sinuated in front of the middle, dorsal margin forming a slightly flattened arch; short hairs along margin except dorsally. Natatory setae of antennae barely reaching or not quite reaching the tips of the terminal claws. Furcal rami large, lamelliform, asymmetrical; dorsal distal margin of one or both rami denticulated, dorsal seta absent, terminal and subterminal claws pectinated. KEY TO THE KNOWN SPECIES OF Stenocypris FROM NORTH AMERICA 1. Pore canals form a prominent striated band along the anterior, posterior and ventral margins 2 Pore canals either absent or not forming striated bands . -...---------------------------S. fontinalis Vavra 1892 2. Both furcal rami denticulated along distal dorsal margin .. - ----------. ..----------------------.-S. malcolmsoni (Brady 1886) Only left ramus denticulated along distal dorsal margin S. bolieki n. sp. Stenocypris bolieki n. sp. Specific Characters: Female.-Shell elongate, reniform, elliptical from above with a mottled green pattern, greatest height posterior, length approximately 2.5X the height; from above valves appear slightly inflated, both extremities rounded, the anterior more broadly rounded than the posterior; dorsal margin forms a slightly flattened arch that slopes anteriorly and posteriorly; pore canals form a prominent striated band except dorsally; surface of valves smooth with scattered puncta, hairs along margin except dorsally. Adductor muscle composed of six bundles of muscle fibers.