Isostenosmylus

Ardila-Camacho, Adrian & Noriega, Jorge Ari, 2014, First record of Osmylidae (Neuroptera) from Colombia and description of two new species of Isostenosmylus Krüger, 1913, Zootaxa 3826 (2), pp. 315-328 : 325-326

Isostenosmylus sp.

( Figs. 1 , 2 a, 3c, 5c–e, 6)

Description. Body length: 11 mm; antennae length: 9 mm; forewing length: 27 mm; hindwing length: 24 mm; length of forewing pterostigma: 4 mm.

Head. Clypeus and labrum pale ochre, covered with setae of the same color. Frons pale ochre with small black spots. Antennal sokets bordering with black. Vertex brown, covered with long and light brown setae arising from black bases; ocelli with black bases. Occiput brown with dark brown pigmentation bordering sutures. Antennae filiform, scape and pedicel light brown, diffusely black pigmented; 46–47 flagellomeres pale ochre, covered with black or pale ochre setae, first 20 with a diffuse black pigmentation.

Thorax. Pronotum narrow, elongated, diffuselly dark brown pigmented and densely covered with long black setae arising from protuberant bases. Mesonotum brown, with black spots on the anterior region, all sclerites covered with brown setae ( Fig. 2 c). Metanotum brown with two lateral brown spots, entire surface with few fine setae. Pteropleura predominantly brown, with abundant pale yellow setae.

Legs. Forecoxa without processes. All segments pale ochre, densely covered with long light brown setae, femora and tibiae with numerous dark brown spots.

Wings. Forewing membrane hyaline, venation alternating pale yellow and brown with abundant setae. Costal field wide, with 66 or 67 crossveins. Subcostal field with one basal crossvein. Pterostigma mottled of pale ochre and brown. Rs with 9–11 branches; three or four presectoral crossveins. CuA long, forking near to the midlength of the wing. Some crossveins in the radial field maculated. Two nygmata present, the first near to the level of separation of MA and Rs, the second between the first Rs fork and MA at level of the third Rs fork ( Fig. 1 ). CuA, MP fork, Rs and radial field with some dark amber spots. Rs with only one row of gradate crossveins composed of five veinlets. Hindwing narrow, membrane hyaline, apex acuminate; venation and pterostigma with a pigmentation pattern similar to forewing, without spots. Subcostal area with one basal crossvein. Rs with ten branches, five or six presectoral crossveins.

Abdomen. Light brown, densely covered with ochre or ligth yellow setae.

Female terminalia. Sternite VII in lateral view posteroventrally slightly produced ( Fig. 5 c); in ventral view posteromedially with subquadrate lobe, posterolaterally rounded ( Fig. 5 e). Sternite VIII slightly sclerotized, with two lateral mamiliform lobes near to the midlength of the segment ( Fig. 5 c). Gonocoxite VIII in lateral view short, ventrally with rounded lobe at base, slender in the middle, apex with two lateral lobes, laterally projected, subcylindrical, with apex rounded; in ventral view slightly widened at base, medially narrowed, distally widened, with two lateral lobes laterally projected, posteromedially with v-shaped concavity ( Fig. 5 e). Tergite IX, gradually widened laterobasally, posteroventrally with tuft of setae. Gonocoxites IX slightly acuminate, apex rounded. Ectoproct in lateral view rounded. Spermatheca subspherical ( Fig. 5 d).

Bionomic data. The specimen was collected with Malaise trap in a Sub Andean forest, in the vicinity of streams in the region of Tequendama (Cundinamarca departament).

Material examined. Cundinamarca: San Antonio del Tequendama, foundation Granja Ecológica el Porvenir, 1540 m, 7-8-II-2011, N. Martelo, Malaise trap (1♀ UNAB).

Remarks. Distinguished from other Colombian species by having forewing with radial field, Rs, MP fork and CuA with few amber spots. Female genitalia with two well developed lateral mamiliform lobes on sternite VIII; gonocoxite VIII short, basal- and apically wider than medially, apical lobes short and slender; spermatheca subspherical. Moreover, this species lacking of preapical dentiform process on the dorsal surface of forecoxa. The pattern of pterostigma and the scarce pigmentation of the wings is very similar to I. fusciceps , however, because I. fusciceps was described from a single male specimen, it is unreliable to assign this specimen to this species. Simultaneously, according to the wing illustration and description of Kimmins (1940) we can not decide if they are different species or not, due to their remarkable resemblance.

Figures

FIGURE 1. Isostenosmylus sp., wing venation; arrow indicating the basal nygma.

FIGURE 2. Isostenosmylus spp., female: a, Isostenosmylus sp.; b, I. contrerasi; c, I. septemtrionalandinus.

FIGURE 5. Isostenosmylus spp.: a, b, I. septemtrionalandinus, (a) female terminalia, lateral, (b) female terminalia, ventral; c – e, Isostenosmylus sp., (c) female terminalia, lateral, (d) spermathecae, lateral, (e) female terminalia, ventral.