Oxyurella ciliata Bergamin, 1939

Elías-Gutiérrez, Manuel, Kotov, Alexey A. & Garfias-Espejo, Tania, 2006, Cladocera (Crustacea: Ctenopoda, Anomopoda) from southern Mexico, Belize and northern Guatemala, with some biogeographical notes, Zootaxa 1119, pp. 1-27 : 19

Oxyurella ciliata Bergamin, 1939 ( Figs. 58–64 )

Material examined: several females from each of the following localities: Silvituc, Km 51 and Charco 3 ( Mexico).

Body 0.38–0.42 mm, oval, posterior margin convex, with postero­ventral angle curved, not armed with spines, with a row of spinules which runs from margin to inner side of valves ( Fig. 58 ). Head with a slight depression in the posterior part. Head shield with main pores not connected, two connected small pores between them ( Fig. 60 ). Rostrum projected with a round tip, covering antennules and partially aesthetascs. Labrum wide not pointed, with a noticeable row of setules along anterior margin ( Fig. 61 ). Second antenna with spine formula: 1–0–1/0–0–1 and setal formula: 0–0–3/1–1–3, in some specimens segments armed with small setules ( Fig. 62 ). Postabdomen with anal spines increasing in size distally, only the distalmost ones smaller (near base of claws). Larger anal spines each with a small bifurcation one third from tip ( Fig. 63 ). Postabdominal claws with one basal spine and a small spinule near the insertion with postabdomen. Lateral setae arranged in groups ( Fig. 64 ).

Oxyurella ciliata ( Bergamin, 1939) has been observed in Venezuela by Rey and Vázquez (1986) and Zoppi de Roa and Vasquez (1991). In Central America, a single specimen was found in Lake Peten, Guatemala (Van de Velde et al., 1978). In Mexico, Dimas­Flores (2002) also found a single specimen in the Coatzacoalcos River. All reports are based in one to three specimens so this is a rare cladoceran. Males are not known.

Figures

FIGURES 58 – 64. Oxyurella ciliata, from La Esperanza 1, Mexico. 58) Lateral view; 59) Posterior margin of valve; 60) Head pores; 61) Labrum; 62) A 2, lateral; 63) Postabdomen; 64) Distal part of postabdomen with claws. FIGURES 65 – 76. Oxyurella longicaudis from Sabancuy, Campeche State, Mexico. 65) Habitus; 66 a – b) Labrum, variation in shape; 67) Posterior margin of valves; 68) A 2, lateral; 69) Postabdomen; 70) Distal part of postabdomen with claws; 71) Closer view of ODL; 72) Limb I; 73) Limb II; 74) Limb IV; 75) Close view of inner side of endite and gnathobase of limb IV; 76) Limb V.