Stenorrhachus chilensis Miller and Stange, 2012

Miller, Robert B. & Stange, Lionel A., 2012, A new species of Stenorrhachus McLachlan from Chile (Neuroptera: Nemopteridae) with biological notes, Insecta Mundi 2012 (226), pp. 1-8 : 2-4

Stenorrhachus chilensis Miller and Stange , new species

( Figures 1-9)

Holotype male. 16 km. south Vallenar , Antofagasta, Chile, 1000 m., 10.II.1989, R. Miller & L. Stange ( FSCA).

Diagnosis. Labial palpus about as long as maxillary palpus, basal segment about 1.5 times longer than greatest diameter, second segment with small apical setae; postventral lobe of male ectoproct about as long as greatest diameter; male paramere about eight times longer than greatest width; mediuncus nearly straight at middle, then bent strongly backwards at lateral margin with a large latero-dorsal process near angle.

Description. Holotype male: length of body 12 mm, forewing 24 mm., greatest width 10 mm. hindwing 59 mm. Coloration: general coloration light brown to pale yellow; face ( Figure 1) mostly pale yellowish ventrally becoming darker dorsally; scape and petiole mostly pale yellow with small dark brown ring apically; antennal flagellomeres brown with very narrow pale ring apically; vertex ( Figure 2) mostly pale yellow with dark brown anterior row and posterior row connected with narrow dark brown stripe medially; large black area behind antennal sockets; pronotum ( Figure 4) without definite markings, mostly dark brown with some pale yellow and with brown spots at base of most setae; mesonotum mostly dark brown anteriorly and laterally, pale yellow in middle before scutellum which has a large brown median area and has pale yellow brown spots at base of many setae; pleura straw colored, mottled with darker brown; legs ( Figure 5) mostly pale brown with coxae mostly dark brown except apically; femur with considerable dark brown anteriorly, tibia with small subbasal and apical dark brown rings; tarsi pale brown; pretarsal claws dark brown; abdomen ( Figure 3) predominately dark brown except for terminal segments which are mostly pale brown dorsally, dark brown spots at many setal bases; wings ( Figure 6) translucent except some brownish suffusion in costal and subcostal area; wing veins and crossveins uniformly dark brown. Chaetotaxy: all setae on body and wings dark brown; leg setae short, shorter than diameter of leg; conspicuous setae present on pronotum, pteronotum, abdomen, and longest on terminalia ( Figure 8). Structure: labial palpus about as long as maxillary palpus, basal segment about 1.5 times longer than greatest diameter, second segment with small apical setae; antenna with about 45 flagellomeres which are mostly about twice as long as broad; head ( Figure 1) with interocular distance about twice as long as vertical distance from labrum to vertex; pronotum ( Figure 4) much wider posteriorly than anteriorly; abdomen short, about as long as length of head and thorax together; forewing venation ( Figure 8); hindwing elongate, ribbon-like, not expanded posteriorly; genital capsule (tergites IX to XI) enlarged, much wider than rest of abdomen; sternite IX reaching to posterior margin of postventral lobe of ectoproct which is about as long as greatest diameter; paramere about eight times longer than greatest width ( Figure 9); mediuncus nearly straight at middle, then bent strongly backwards at lateral margin with large broad latero-dorsal process near angle ( Figure 8).

Variation: length of body 7 to 12 mm., forewing 15 to 24 mm., hindwing 42 to 60 mm.

Paratypes. 25 males. February. CHILE. Antofagasta: 16 km. south Vallenar , 1000 m., 10.II.1989, R. Miller & L. Stange (at light) (20 m, 23f, CASC; FSCA; PCRM; TAMU; USMB). Coquimbo: Vicuña, 9.II.1989, R. Miller & L. Stange (2m, FSCA) .

Discussion. This species differs notably from S. walkeri in the shorter male ectoproct (postventral lobe about as long as greatest diameter) and male genitalia ( Figures 8, 9) which has the anterior fragment of the male paramere longer and more slender and the gonarcus which has a broad latero-dorsal process near the strong posterior angle. S. chilensis appears to be somewhat smaller (forewing 15 to 24 mm) than S. walkeri (forewing 23 to 27 mm) and has darker markings. Also, the labial palpus and pretarsal claws are shorter and the male abdomen of S. chilensis is slightly longer than in S. walkeri . This species occurs at high elevation (1000 meters) whereas S. walkeri appears to prefer the coastal sand dunes.