Lachesilla willistoni, García Aldrete, 2017

García Aldrete, Alfonso N., 2017, New species of Lachesilla (Psocodea: Psocomorpha: Lachesillidae), in species group corona, from southern Mexico and Central America, Zootaxa 4347 (2), pp. 201-227 : 225

Lachesilla willistoni n. sp. Female

( Figs 68–71 )

Diagnosis. Subgenital plate wide, posteriorly glabrous, concave in the middle. Flap long, almost twice as long as wide, proximally concave, with antero-lateral corners projected outward, posterior border rounded. Gonapophyses club-shaped, each with six setae as illustrated. Ninth sternum broadly triangular, posteriorly rounded; posterior third hyaline, bearing centrally the spermapore.

Description. Color (40 years in 80% ethanol). Body reddish brown. Compound eyes black, ocelli hyaline, without pigmented centripetal crescents. Maxillary palps, antennae and legs pale brown. Wings hyaline, veins pale brown, R1 and stigmasaum ochre. Abdomen pale brown, with ochre subcuticular rings, faded ventrally.

Morphology. As in diagnosis, plus the following: Forewing pterostigma long, wider distally, Rs-M meeting at a point, areola postica triangular, apically rounded, slightly slanted posteriorly ( Fig. 68 ). Subgenital plate ( Fig. 69 ), with pigmented area slightly concave anteriorly in the middle, flap ( Fig. 69 ). Gonapophyses ( Fig. 70 ), joined to clunium, slightly concave posteriorly. Ninth sternum ( Fig. 70 ), with two anterior thirds pigmented, spermapore with pigmented rim. Paraprocts broad ( Fig. 71 ), almost semicircular, setae as illustrated, sensory fields with 10 trichobothria. Epiproct ( Fig. 71 ) broadly trapeziform, with setal field on posterior third.

Measurements. FW: 1722, HW: 1327, F: 319, T: 622, t1: 190, t2: 79, ctt1: 10, Mx4: 90, f1: 178, f2: 134, f3: 111, f4: 91, f5: 66, f6: 65, f7: 57, IO: 284, D: 141, d: 99, IO/d: 2.86, PO: 0.70.

Specimen studied. Holotype female. COSTA RICA. Puntarenas Province. Finca Las Cruces, near San Vito. 11.vi.1977. Beating understory forest vegetation. E. L. Mockford ( ISU).

Etymology. This species is dedicated, in memoriam, to S. W. Williston, co-author of the Insecta. Diptera. Volume I (1886–1901), of the Biologia Centrali-Americana.

Remarks. This species is related to L. championi n. sp., described above. For differences between them see Remarks under L. championi n. sp., above.

Figures

FIGURES 68 – 71. Lachesilla willistoni n. sp. Female. 68. Fore- and hind- wings. 69. Subgenital plate. 70. Gonapophyses and ninth sternum. 71. Epiproct and right paraproct. Scales in mm. Figures 70 and 71 to common scale.