On the Miocene Cyprideis species flock (Ostracoda; Crustacea) of Western Amazonia (Solimões Formation): Refining taxonomy on species level Author Gross, Martin martin.gross@museum-joanneum.at Author Ramos, Maria Ines F. mramos@museu-goeldi.br Author Piller, Werner E. martin.gross@museum-joanneum.at text Zootaxa 2014 2014-12-18 3899 1 1 69 journal article http://dx.doi.org/10.11646/zootaxa.3899.1.1 1175-5326 PMC5229818 25543674 4957307 D78F2010-08E1-45C0-86FF-7F2D3601070D Cyprideis olivencai ( Purper, 1979 ) Figs. 4l–m ; Pl. 4, Figs. 1–8 , 25, 28 * 1979 Paulacoutoia olivencai Purper , gen. et sp. nov. —Purper: 235–236; Pl. 5, Figs. 10 –17. pars 1998 Cyprideis olivencai ( Purper, 1979 ) —Muñoz-Torres et al. : 100; Pl. 4, Fig. 6 . [non Pl. 4, Figs. 5 , 7 ] pars 1998 Cyprideis olivencai ( Purper, 1979 ) —Whatley et al. : 236; Pl. 2, Figs. 1–2 [sic]. [non text-Fig. 2 (next to last row, right), non Pl. 2, Figs. 3–5 [sic]] ? 2010 Cyprideis olivencai ( Purper, 1979 ) —Wesselingh & Ramos: 308; Figs. 18.5o–p. ? 2011 Cyprideis olivencai —Linhares et al. : 97; Figs. 4 /1–2. ? 2013 Cyprideis ? olivencai ( Purper, 1979 ) —Gross et al. : 229; Pl. 6, Figs. 21, 23–27. Material. 34 valves; samples AM 10/6–7. Dimensions (total range over all samples). R ♀ l = 0.75–0.80 (0.77), h = 0.38–0.41 (0.39; n = 7); L ♀ l = 0.73–0.82 (0.77), h = 0.38–0.43 (0.41; n = 3); R ♂ l = 0.76–0.79 (0.77), h = 0.35–0.36 (0.35; n = 3); L ♂ l = 0.79, h = 0.42 (n = 1). Remarks. The type material of Purper (1979) matches well with the present specimens, although a bit more elongated than the valves described here. We assume this slight difference in outline to be intraspecific variability. Muñoz-Torres et al. (1998) and Whatley et al. (1998) synonymised several species under C . olivencai ( C . multiradiata , C . paralela , C . simplex ). Due to large and consistent differences (e.g. outline, inner lamella, hinge), we consider those three species as separate and valid taxa (see chapters 4.5.4. and 4.5.5.). C . olivencai (sensu Purper (1979) and this work) is a smooth, asulcate, subovate–subtrapezoidal species with a wide anterior inner lamella, large vestibulum and narrow fused zone. Marginal pore canals are short, branched or ramified. The hinge (right valves) consists of denticulated, anterior long and posterior shorter elements. The crenulated, long median element is divided into a negative anteromedian and a positive posteromedian part. Sexual dimorphism is expressed by more elongated male valves with a more pointed posterior margin. Figures given in Wesselingh & Ramos (2010) and Linhares et al. (2011) coincide well in outline with the current material. However, details (e.g. hinge) of the inner valve characters are not visible. Likewise, the rare specimens of Gross et al. (2013) correspond in outline, but have, quite unusually, smooth hinge elements. C . olivencai is very similar to C . kroemmelbeini with which it co-occurs (see below). The most obvious divergence of C . kroemmelbeini is the inverse hinge and reverse right and left valve overlap respectively (constantly found in both sexes as well as in juveniles; Pl. 4, Figs. 9 –24). By comparing the outlines of right valves of C . olivencai with mirrored (!) left valves of C . kroemmelbeini further differences are on hand. In left valves of the latter, the outline of the anterior proportion of the ventral margin displays a straight course over a short distance due to a slight projection of the flange ( Purper 1979 ; Pl. 4, Figs. 25–28). Mirrored right valves of C . kroemmelbeini display a slightly more expressed ventral concavity in comparison to left valves of C . olivencai (compare Pl. 4, Fig. 2 ( C . olivencai ) with Pl. 4, Fig. 29 ( C . kroemmelbeini , mirrored)). If an inverse hinge and such rather subtle differences in outline are species diagnostic remains unclear ( Kollmann 1960 ; Van Morkhoven 1962 ; Purper & Pinto 1985 ). It is possible that C . kroemmelbeini is synonymous with C . olivencai (but certainly not with C . machadoi as suggested by Muñoz-Torres et al. (1998) and Whatley et al. (1998)) . Because we found two clearly differentiable morphotypes with females, males and juveniles within one sample, reproductively separated species are probable. For this reason, we decided to distinguish both forms here. Occurrence (of C . olivencai sensu Muñoz-Torres et al. 1998 ). Western Amazonia ( Brazil , Colombia , Peru ), early Middle to early Late Miocene ( C . aulakos – C . cyrtoma zone; Muñoz-Torres et al. 2006 ; chronostratigraphic correlation after Wesselingh & Ramos 2010 ).