Lachesilla jacobyi n. sp. Male

(Figs 43–45)

Diagnosis. Related to L. horni n. sp., differing from it in having the distal halves of the posterior processes of the hypandrium much longer and decidedly curved inward, in lacking a sclerotized band along the posterior border of the hypandrium, and in having the inner and outer corners of the posterior borders of the phallosome apodemes pointed.

Description. Color (34 years in 80% ethanol). Body reddish brown. Compound eyes black, ocelli hyaline, without pigmented centripetal crescents. Legs and antennae brown. Maxillary palps dark brown. Wings hyaline, veins brown, R1 and stigmasaum ochre. Abdomen whitish, with brown subcuticular rings faded ventrally.

Morphology. As in diagnosis, plus the following: Compound eyes almost at the same level of the vertex. Forewing pterostigma long, much wider distally, Rs-M fused for a short distance, areola postica triangular, rounded apically (Fig. 43). Hypandrium wide, with a setal field on each side, posterior border straight between the posterior processes, these posterior processes proximally wide, distally long, slender, curved inward (Fig. 44). Phallosome (Fig. 44), V shaped anteriorly, apodemes slender, widening distally, with distal third dilated, and with outer and inner corners pointed. Paraprocts (Fig. 45), broad, rounded, sensory fields with 13–14 trichobothria, limited by sclerotized band on inner border; prong long, distally truncate. Epiproct (Fig. 45), wide, straight anteriorly, bilobed posteriorly, setae as illustrated.

Measurements. FW: 3088, HW: 2378, F: 604, T: 1086, t1: 364, t2: 119, ctt1: 20, Mx4: 123, f1: 337, f2: 297, f3: 248, f4: 210, f5: 122, IO: 376, D: 213, d: 144, IO/d: 2.61, PO: 0.67.

Specimen studied. Holotype male. MEXICO. Chiapas. Angel Albino Corzo. El Triunfo Biosphere Reserve. 7 km SW Finca La Prusia (Jaltenango). 1850 m. 4.iii.1983. Beating vegetation in cloud forest. R. Medellín. Etymology. This species is dedicated, in memoriam, to Martin Jacoby, author of the Insecta. Coleoptera . Phytophaga (part). Volume VI, Part 1 (1880–1892), and Insecta. Coleoptera . Phytophaga (part). Volume VI, Part 1 (Supp.) (1880–1892), of the Biologia Centrali-Americana.

Remarks. This species is close to L. horni n. sp., described above; for separation of the two species, see under Remarks on L. horni n. sp., above.