Drepanoneura loutoni sp. nov.

Figures 1 b, 2h–i, 6, 11b, 17, 27e–30e, 36f, 37

Etymology. We name this species loutoni (noun in the genitive case) in honor of our good friend and colleague Jerry A. Louton, who collected this species in Peru, in recognition of his contributions to the knowledge of New World Odonata and his friendship and continuous assistance.

Specimens examined. Total 72 ɗ, 6 Ψ.— Holotype ɗ: Peru, Madre de Dios Department, Manu, Pakitza, trail 1 (12°07'S, 70°58'W, 250 m), 12 ix 1988, leg. O.S. Flint, Jr. (USNM). Paratypes: Ecuador: Morona-Santiago Province: 1 ɗ, Mayalico, on Río Nanganita (now Río Naganitza) (03°03'33''S, 77°59'44''W, 490 m), 0 2 xii 1941, leg. D.B. Laddey (UMMZ). Peru, San Martín Department: 5 ɗ, 1 Ψ, vicinity of Rioja (Soritor), in jungle (06°02'S, 77°10'W, 900 m), 13 x 1936, leg. F. Woytkowski (UMMZ); 4 ɗ, same data (RWG); 2 ɗ, same data but 14/ 17 x 1936 (UMMZ); 1 ɗ, same data but 17 x 1936 (RWG). Huánuco Department: 1 ɗ, Tingo María, muddy stream (08°58'S, 75°50'W, 440 m), 0 4 vii 1977, leg. D. Paulson (DRP). Junín Department: 5 ɗ, Satipo (11°16'53''S, 74°41'''W, 714 m), 05/ 25 vi 1940, leg. P. Paprzycki (UMMZ); 3 ɗ, same data but 05/ 18 vi 1940 (RWG); 7 ɗ, same data but 05/ 31 vii 1940 (UMMZ); 4 ɗ, same data (RWG); 3 ɗ, same data but 09/ 10 viii 1940 (UMMZ); 1 ɗ, same data (RWG); 3 ɗ, same data but 19/ 23 x 1940 (UMMZ); 2 ɗ, same data but 23/ 25 x 1940 (RWG); 10 ɗ, same data but 10/ 31 xii 1940 (UMMZ); 4 ɗ, same data but 16/ 30 xii 1940 (RWG); 2 ɗ, same data but 0 1 i 1941 (UMMZ); 1 ɗ, same data but 0 3 i 1941 (RWG); 1 ɗ, same data but xii 1941 (UMMZ); 1 ɗ, same data (RWG). Cusco Department: 2 ɗ, Camisea R. drainage, San Martín "C", Shell Oil gas exploration site (11°46'53''S, 72°42'06''W, 431 m), 19/ 24 ii 1997, leg. J. Louton (RWG). Madre de Dios Department: 1 ɗ, Manu, Pakitza, trail 1 (12°07'S, 70°58'W, 250 m), 12 ix 1988, leg. O.S. Flint, Jr. (RWG); 2 ɗ, same data but (TWD); 1 Ψ, same data but 17 ix 1988 (TWD); 1 Ψ, same data but 23 ix 1988 (USNM); 2 ɗ, same data but marker 14, first stream, 09/ 19 ix 1989, leg. N.E. Adams (USNM); 1 ɗ, 1 Ψ, same data but Trail 2, marker 18, seeps, 12/ 17 ix 1989 (USNM); 2 ɗ, 1 Ψ, same data but marker 15, first stream, 18 ix 1989 (USNM); 1 Ψ, same data (RWG).

Male holotype. Head. Labium, labrum except medio-basal black spot, and second antennal segment pale yellow; base of mandibles, anteclypeus, genae, ventral half of antefrons, and triangular spot on anterior surface of antennifer pale blue, remainder of head black (as in Fig. 1 b).

Thorax. Prothorax, mesepisternum, mesepimeron, and stripe along dorsal margin of metapleural suture black with metallic green and copper reflections; stripe along ventral margin of humeral suture, metepisternum, metepimeron, and pterothoracic venter pale yellow (Fig. 2 h); coxae and trochanters yellow; femora yellow with black apical band; tibiae, tarsi, and pretarsi yellow with black apices; 4 spurs on metafemora, 6 on metatibiae. Hw 5.6 times as long as wide; 13 Px in right Fw, 12 in left Fw, 10 Px in Hw; MP reaching wing margin at vein descending from subnodus; IR2 arising slightly distal to vein descending from subnodus; IR2 and RP 3 separated by a short crossvein one cell posterior to their origin; RP 2 beginning closer to Px 5 in right Fw, to Px 6 in left Fw, and to Px 4 in both Hw; pt pale brown with marginal yellow hairline, shorter than underlying cell, with costal side slightly shorter than posterior side.

Abdomen. Dorso-laterally black with metallic reflections except for narrow yellow bands interrupted medio-dorsally by black on base of S3–7; latero-ventral portion of terga and sterna pale brown to yellow. Apex of genital ligula with a deep u-shaped cleft (as in Fig. 17 a) with long and broad latero-distal lobes curved medially (as in Fig. 17 c). Dorso-posterior margin of S10 not projected posteriorly (as in Figs. 27 e– 28e). Ventral branch of cercus longer than base of cercus, approximately cylindrical (as in Fig 28 e); in posterior view aligned with inner margin of cercus at base and diverging distally from ventral branch of opposite cercus (as in Fig. 30 e). Paraproct truncate (as in Fig. 28 e).

Dimensions. Total length 35.9 mm; abdomen length 30.8 mm; Hw 18.6 mm.

Paratypes. Paratypes are similar to holotype but vary as follows: femora banded to entirely dark brown; 4–6 spurs on metafemora, 5–6 on metatibiae; Hw 5.4–5.8 times as long as wide; 11–13 Px in Fw, 9–11 Px in Hw; MP reaching wing margin from vein descending from subnodus to half-length of the cell distal to it; and IR2 arising at vein descending from subnodus or slightly distal to it (Fig. 11 b). Posterior margin of female pronotum is trilobate with a medio-dorsal triangular projection, a dorso-lateral flat rounded process adjacent to medial projection and a ventro-lateral digitiform process on each side (Fig. 6); and the dorsal side of subbasal plate of ovipositor is concave and ventral side slightly convex (Fig. 36 f).

Dimensions. Males (n = 10): total length 34.2–38.6 mm [mean 36.1 mm; SD 1.2]; abdomen 29.6–33.4 mm [mean 31.1 mm; SD 1.1]; Hw 18–19.8 mm [mean 18.6; SD 0.6]. Females (n = 6): total length 32.6–37.3 mm [mean 34.6 mm; SD 1.7]; abdomen 27.5–32 mm [mean 29.6 mm; SD 1.6]; Hw 19–21.3 mm [mean 19.8 mm; SD 0.8].

Diagnosis. Male of D. loutoni shares only with D. tennesseni the medially directed long and broad lateroapical lobes of genital ligula (Fig. 17 c) and truncate paraproct (Fig. 28 e), but differs by the approximately cylindrical ventral branch of cercus (Figs. 29 e–30e), and usually by the presence of a narrow yellow stripe along most of humeral suture (Fig. 2 h; obscured in some specimens). Female shares with D. tennesseni the pronotal posterior margin with a triangular medio-dorsal projection and posteriorly directed digitiform ventrolateral processes, but it differs by the presence of a pair of dorso-lateral flat rounded processes adjacent to the medial projection (Fig. 6).

Biology. Specimens from Cusco Department were found at a large stream perched on vegetation just above water's surface and flying just above water in the sun and were hard to net (data from collection label). Felix Woytkowski included following notes with specimens he collected at Soritor: "keeps exclusively in shade beneath large trees growing along the river flowing across the jungle; lives in bushes fringing the waters, often hanging above the river and it is difficult to detect in account of the semidarkness; when disturbed rises up and lands on leaves of higher trees."

Distribution. Ecuador to Peru, from Morona-Santiago Province to Madre de Dios Department (Fig. 37).