Hydraena ecuadormica, new species

Figs. 115 (habitus), 117 (aedeagus), 199 (map)

Type Material. Holotype (male): Ecuador: Los Rios, Quevedo, 1° 2' S, 79° 28' W, 11 v 1975, Spangler, et al. Deposited in the USNM. Paratype: Same data as holotype (1 USNM).

Differential Diagnosis. A broad species with very fine and sparse punctation, and subtruncate elytral apices. The holotype and female paratype are teneral; in mature specimens the pronotum probably has a piceous fascia, bordered anteriorly and posteriorly by testaceous margins. Similar in dorsal habitus and ventral characters (including very narrow P2) to H. premordica Perkins (1980) (Figs. 114–115); differentiated therefrom by the smaller size (ca. 1.50 vs. 1.76 mm) and differences in male characters. In males of H. premordica the elytral apices are much more truncate, the protibiae are weakly arcuate, and have a tooth-like expansion at the distal 1/3; legs of H. ecuadormica are simple. The aedeagi of the two species, while showing some similarities, markedly differ in other details, and should be examined for reliable determinations (Fig. 116–117).

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.50/0.66; head 0.27/0.38; pronotum 0.40/0.51, PA 0.41, PB 0.49; elytra 0.93/0.66. Color uncertain (holotype and female paratype teneral); pronotum apparently testaceous in front of and behind brown fascia or macula, ratios of color bands, as measured in midline, ca. 5/15/5. Maxillary palpi testaceous, tip not darker.

Frons punctures ca. 1xef, slightly larger and denser near eyes than medially; interstices shining, 1–2xpd laterally, 3–6xpd medially. Clypeus microreticulate laterally, very finely sparsely punctulate medially. Mentum finely, moderately densely punctulate, interstices shining; postmentum very finely densely micropunctulate in median concavity, surrounding areas smooth, shining, finely punctulate. Genae raised, shining, without posterior ridge.

Pronotum arcuate laterally; anterior margin straight behind eyes, emarginate behind frons, scintilla absent; punctures on disc very fine and sparse, slightly smaller than those of frons, interstices strongly shining, medially 4– 7xpd, punctures denser at anterior and posterior; PF1, PF2 and PF4 absent; PF3 deep.

Elytra weakly arcuate laterally; summit of posterior declivity at ca. midlength; lateral explanate margins narrow; on basal 1/3 punctures slightly larger than largest pronotal punctures, punctures not becoming appreciably finer and more widely spaced toward posterior. Intervals not raised, shining, on basal 1/3 ca. 2–4xpd, as are interstices between punctures of a row, a few punctures subserial. Apices in dorsal aspect subtruncate, in posterior aspect margins forming deep angle with one another.

Ratios of P2 width and plaque shape (P2/w/l/s) ca. 2/2/6/5. P1 laminate; median carina sinuate in profile. P2 narrow, l/w ca. 3/1, sides parallel, apex blunt, raised slightly above mesoventral intercoxal process. Plaques moderately narrow, straight, widest posteriorly, becoming obsolete anteriorly, slightly converging toward one another anteriorly, weakly raised, located at sides of median depression. Metaventrite produced in small point extended posteriorly from margin of each mesocoxal cavity. AIS width at straight posterior margin ca. 1.5x P2. Legs slender, simple. Male abdominal apex symmetrical. Female (microslide mount, n=1): last tergite sharply rounded, without apicomedian notch, ca. 24 hooked setae, no median gap; gonocoxite not midlongitudinally divided, apical margin sharply rounded, no transverse ridge evident at border of microreticulation; spermatheca type C1.

Etymology. The specific epithet is a combination of Ecuador and a partial anagram of premordica.

Distribution. Currently known only from the type locality (Fig. 199).