Helicosina Kuwahara & Marshall & Yau 2024

Key to the species of Helicosina This key is based almost entirely on male characters, as the females are almost indistinguishable morphologically. 1 Body length ≤ 1.8 mm. Male fore and hind femora slightly thickened (length 1.9–2.0 × and 4.4–5.6 × width, respectively) (Fig. 2A). Surstylus straight along anterior margin (Fig. 4C). Posterior opening of epandrium roughly triangular, widest ventrally (Fig. 4D).......................................................................... H. crena sp. nov. [CRI] - Body length ≥ 1.9 mm. Male fore and hind femora distinctly thickened (length 2.9–3.2 × and 3.1–3.7 × width, respectively) (Figs 2C, 2E). Surstylus sinuate, curved along anterior margin (Figs 5C, 6C). Posterior opening of epandrium ovoid or circular, widest around the middle (Figs 5D, 6D)................................................................... 2 2 Eye height 3.1–3.2 × genal height; face only slightly protruding. Male S5 longer, width 2.4–2.7 × length (Fig. 5A). Posterior opening of epandrium almost circular (height 0.9–1.0 × width) (Fig. 5D). Surstylus bulging basally, apical half gently sinuate (Fig. 5C). Postgonite parallel-sided basally, truncate apically (Fig. 5B). Distiphallus with a lateral row of thickened setulae (Fig. 5B)............................................................................... H. sica sp. nov. [ECU] - Eye height 3.6–3.7 × genal height; face distinctly protruding. Male S5 shorter, width 4.2–4.5 × length (Fig. 6A). Posterior opening of epandrium roughly ovoid (height 1.3–1.4 × width) (Fig. 6D). Surstylus roughly parallel-sided basally, apical half strongly bent at about a right angle (Fig. 6C). Postgonite broadened basally, triangular apically (Fig. 6B). Distiphallus densely microtomentose dorsally but without longer setulae (Fig. 6B)............................ H. valga sp. nov. [CRI, PAN]