Anacroneuria varilla Stark, 1998

Figs. 22–23

Description. Body length: 10 mm. Head (Fig. 22): brown forward of ocelli; pale m- line and pale anterior frontoclypeus. Pronotum: oval, widest anteriorly, as wide as mesonotum; brown with pale well defined rugosities forming an indistinct median stripe. Margins completely fringed with short, thick bristles, somewhat variable in length.

Meso- and Metanotum: pale midline; wing pads dark but with teardrop shaped pale areas distally. Dorsal surfaces covered with fine short setae, and scattered thick bristles; well-defined anterior and lateral lines of thick bristles. Margins completely fringed with thick bristles, somewhat variable in length. Foreleg (Fig. 23): dorsal surfaces covered with fine short setae, except for hairless median bar and basal posterior triangle-shaped area on femur. Femur dorsally with well-defined transverse row of six long, thick spines; scattered short and medium-sized spines on dorsal surface; basal posterior patch of very small spines along margin, reaching transverse row of long spines.

Distribution. Costa Rica, Panamá.

Local distribution (Fig. 24): A single specimen was collected from a river in the northern lowlands.

Reared specimens. Alajuela: Tributary Río Pizote, Upala, 250 m, 3.xii.2006, Gutiérrez, 13.

Habitat and substratum. Submerged leaf litter packs in strong current; in a medium sized river with dense forest cover.

Diagnosis. Anacroneuria varilla is very similar in color pattern on head and thorax (Fig. 22) to A. lineata, but presents fewer spines on the foreleg (Fig. 23). Unfortunately only one specimen was reared to adulthood; therefore, the diagnostic characteristic for this species requires confirmation through the association of additional specimens.