Escura nigrosignata (Tillyard)

Miller, Robert B. & Stange, Lionel A., 2012, The cave mouth antlions of Australia (Neuroptera: Myrmeleontidae), Insecta Mundi 2012 (250), pp. 1-65 : 24-25

Escura nigrosignata (Tillyard)

( Figures 29, 30, 31, 79, 80)

Distoleon nigrosignatus Tillyard, 1916 . Holotype male, Cottesloe , Western Australia, Feb.-March 1913 (BMNH).

Further description: New 1985c: 20, figures 1183-1189 (wings; male, female terminalia, male genitalia).

Description. Adult: antenna about 6 to 8 mm; body about 20 to 24 mm; forewing 24 to 29 mm, hindwing 22 to 27 mm. Coloration: body dark brownish gray with grayish yellow markings; antennal base pale brown, flagellum and distal segments black with narrow pale apices; palpi pale except black apical segment of labial palpus; frons mostly dark brown to black; vertex dark brown except for central lateral transverse yellow patch; posteriorly with paired median spots and 2 lateral spots; pronotum with two broad grayish brown stripes narrowly separated by pale midline; ventral lateral margin pale brown; pterothorax dark brown, with slight traces of yellow streaks along lateral scutal lobes; abdomen dark brown, tergites beyond II with traces of anterior paired pale streaks, posterior rim usually narrowly pale; wing venation mostly pale brown except for some shaded areas; Sc dark at intersections with costal crossveins; hindwing radial sector stem dark brown; pterostigma white to cream, other markings as in Figure 30; femora mostly black, fore and midtibia with three black bands, including apex; meta tibia more extensively pale; tarsus dark brown except bases of I, V and sometimes II. Chaetotaxy: clypeus with about 19 long, pale hairs; femur with white hairs and few black setae. Structure: antenna slender, club well defined; pronotum slightly longer than broad; wings tapered, venation as in figure 30; legs short and sturdy; tibial spurs long slender, extending to beyond apex of tarsomere IV; pretarsal claws long, slender, about equal to spurs; male ectoproct large, sternite IX short; gonarcus broadly arched, mediuncus membranous; parameres simple, slender; female abdominal ectoproct not ornamented, lateral gonapophysis moderately broad; posterior gonapophysis slender; spermatheca broadened apically.

Larva: Coloration: body pale brown with extensive dark brown markings; mandibles pale brown, pretarsal claws reddish; head capsule above with lateral margin mostly dark brown, dark brown submedial stripe and V-shaped mark near anterior margin; venter of capsule mostly pale brown with small dark brown spot sublaterally near posterior margin and pale brown short stripe slightly posterior to sublateral spot. Chaetotaxy: dorsal surface with moderately long dolichasters; sternite IX with two groups of stout digging setae submedially near posterior margin, medial tooth of each group peg-like, not much longer than broad and about equal to submedial peg-like setae situated a little anterior to others. Structure: head capsule about as long as anterior width (dorsal view), somewhat shorter than length of mandibles; mandibles with 3 teeth increasing in length distally, middle tooth a little closer to distal tooth than to basal tooth; distance between teeth longer than distance from mandibular base to basal tooth; antenna about half as long as head capsule width; labial palpus slightly longer than base of mandible; mesothoracic spiracle borne on short tubercle which is shorter than greatest breadth; anterior thoracic scolus about as long as greatest diameter; abdominal spiracles raised above tegument on tubercle that is much broader than long; sternite VIII without submedian teeth near posterior margin; sternite IX about 1.5 broader at anterior margin than long.

Distribution: Queensland; South Australia; Western Australia.

New records. AUSTRALIA. Western Australia: 9 km. north Wanneroo, S 3 o, 39' 25", E 115 o, 44', 8", 9. III. 1994, R. Miller & L. Stange (reared) (5m, 4f, FSCA).

Discussion. The adult of this species can be distinguished from other species of Escura by the dark brown longitudinal streak which extends most of the length of the forewing. About fifteen larvae were found living under a large rock overhang about nine kilometers north of Wanneroo. Nine adults were reared. The time spent in the cocoon ranged from 33 to 37 days. Seven of the larvae made their cocoons near the end of August 1994. No parasites were present. The larvae live in Zone 4B and occupy the same niche as Xantholeon larvae. They live in the sand in the shade mostly near the rock wall. The third instar larva attains about 15 mm in length.