Erythrodiplax laselva, Haber, William A., Wagner, David L. & Rosa, Carlos De La, 2015

Haber, William A., Wagner, David L. & Rosa, Carlos De La, 2015, A new species of Erythrodiplax breeding in bromeliads in Costa Rica (Odonata: Libellulidae), Zootaxa 3947 (3), pp. 386-396 : 387-393

Erythrodiplax laselva new species

Figures 1 ; 2; 3a–e, i; 4

Etymology. The species name honors the La Selva Biological Station, Organization for Tropical Studies, on its recent 50th anniversary.

Specimens examined. Total 3 males, 2 females, 1 larva, 10 larval exuviae. Holotype male: Costa Rica, Heredia Province, La Selva Biological Station (10.4312o N, 84.0062o W, 50 m), 6 June 2012, eclosed from larva on bromeliad leaf at 06:00, WAH & R. Vargas leg. (INBIO: INB0004435784). Paratypes: 1 male, same site, teneral, 22–30 April 1996, DLW leg. (UCMS); 1 male from same site, eclosed on bromeliad leaf, wings wrinkled, 10 May 2012, CDLR leg. (INBIO: INB0004319191); 1 female from same site, eclosed from bromeliad in a screened cage, 29 May 2012, CDLR & R. Vargas leg. (INBIO: INB0004435785); 1 female from same site, 26 May 2014 CDLR leg. (WAH). Larva: final instar male from same site, 21 May 2014, CDLR leg. (WAH). Exuviae: from same site, 15 April 2012, CDLR leg. (WAH), 21 May 2014, CDLR & R. Vargas leg. (WAH).

Description of male holotype. Head. Labrum, mandibles, anteclypeus, and postclypeus brown, frons brown shading to brown-black on dorsum without metallic blue; prementum cream in basal half, light brown in distal half; vertex brown-black on dorsum bordered by lighter brown on posterior side, a pair of short tubercles on anterior side; setae black. Eyes brown-black on sides, brown on dorsum; occipital triangle brown-black, posterior convex, weakly bilobed with a central groove; underside of head brown, with no pale marks bordering eyes posteriorly ( Fig. 1 a).

Thorax. Prothorax ( Figs. 1 a, 2a) brown without markings, hind lobe wider than long, narrowed at base, weakly emarginate in center, with long orange-brown setae. Pterothorax: mesepisternum ( Fig. 2 a) brown-black with a yellow stripe about 1 mm wide on carina, but not extending into inter-alar space; mesepimeron brown shading to brown-black anteriorly and along upper suture; metepisternum red-brown with a blackish stripe along upper suture; metepimeron red-brown shading to black on posterior half of metapleural suture; underside orangebrown, unmarked. Legs black, the hind femur shading to brown basally, with 9–10 spines in outer row, the distal two subequal. Wings ( Figs. 1 a, 2b) transparent with brown-black shading at base, the HW basal spot extending to the first antenodal crossvein, but not reaching the anal angle; venation black; Pt brown-black, 2.6, 2.8 long in FW, 3.0 in HW; FW Ax 12, 12; Px 9, 8; HW Ax 9, 8; Px 8, 9; FW triangle 2-celled, subtriangle 3-celled, post-triangle space with 3 rows of cells for one cell, followed by 2 rows for five cells; HW triangle 1-celled; anal loop with 16, 17 cells, with 3 cells in basal row.

Abdomen. Mostly orange-brown, S1–2 dark brown-black on dorsum; S8–9 shading to black on posterior dorsum, S10 mostly brown-black. Transverse carina of S2 with straight sides forming a rounded angle of about 100o. Cerci ( Fig. 3 a) brown-black, 1.5 long, ventral angle rounded in profile with 5–6 denticles on lower side; in dorsal view cerci converge to the point of greatest width, then diverge slightly to apex. Epiproct ( Fig. 3 b) 1.3 long, narrowing to 0.2 wide at tip with a pair of sharp dorsal denticles. S2 with vesica spermalis as in Fig. 3 c, d; distal segment 0.85 long; genital lobe ( Fig. 3 e) upright, with rounded distal margin, not overlapping S3.

Dimensions. Head maximum width 5.5; total body length 34, abdomen 22; FW 28, HW 25 long x 9.2 at widest point.

Variation in males (N = 2). The male collected in 1996 is lighter in pigmentation, particularly the Pt, HW basal spot, and pterothorax, than the holotype and the second male kept alive for several days in a flight cage.

Wings. Pt 2.9 in FW, 2.8 in HW; FW Ax 11–13; Px 8–10; HW Ax 8–10; Px 9–10; FW triangle 1-, 2-celled; post-triangle space with 3 rows of cells for two cells, followed by 2 rows for 3, 4 cells; anal loop with 19, 21 cells.

Dimensions. Head maximum width 4.9–5.3; total body length 30–33; abdomen 19–21; FW 25–27, HW 24–25 long x 7.7–8.5 at widest point.

Description of female. Head. Labrum, mandibles, anteclypeus, and postclypeus dark brown, unmarked; frons dark brown with faint blue reflectance; prementum cream in basal half, pale brown distally; vertex dark brown with short anterior tubercles separated by a highly obtuse sinus occupying the central third of vertex width; eyes dark brown; occipital triangle dark brown, posterior margin convex with narrow central groove; underside of head brown, without markings; setae black ( Fig. 1 b). Thorax. Prothorax brown, unmarked; propleuron somewhat rectangular; hind lobe wider than long, strongly narrowed at base, hind margin weakly emarginate in center. Pterothorax: mesepisternum ( Fig. 1 b) dark brown-black, with a broad cream-yellow stripe over dorsal carina, not extending onto inter-alar membrane; mesepimeron red-brown shading to black along antehumeral suture; metepisternum red-brown; metepimeron red-brown with black shading along posterior third of upper suture; underside brown with weak darker spot behind each metacoxa. Legs uniformly black, except hind femur shading to dark brown basally; outer row of spines on hind femur 8, 9, increasing in length uniformly, the last 2 subequal. Wings ( Fig. 2 c) transparent with brown-black shading at base, venation black; Pt dark brown, 2.8 long on costa in FW, 2.9 in HW; FW Ax 11, 11, Px 8, 8; HW Ax 8, 8; Px 8, 7; FW triangle 2-celled, subtriangle 3-celled, supratriangle free, post-triangular space with 3 cells for one cell row, followed by 2 cells for 3, 4 cell rows; HW triangles one-celled; anal loop with cells 18, 20, basal row with 3 cells; base of both wings with brown-black shading, in HW extending to 2nd antenodal crossvein and base of triangle, but not reaching anal angle. Abdomen. Red-brown to light orange-brown, S1–2 and S8–10 darker on dorsum; S2 with transverse carina more curved than in male; vulvar lamina in lateral view ( Fig. 3 i) rounded triangular, barely projecting ventrally; in ventral view shallowly bilobed, the lobes about 1/4 to 1/3 the length of S9; posterior margin of S9 projected ventrally, bearing about 25 stout hairs; cerci broadest in middle, narrowing to sharp points that are directed slightly upward and outward.

Dimensions. Head maximum width 5.9; total body length 35, abdomen 23, FW 27, HW 25 long x 10 wide at widest point.

Variation in female (N = 1). Legs. Outer row of spines on hind femur 7, 7. Wings. Pt 2.6 long on costa in FW, 2.8 in HW; Px 7, 8; HW Ax 9, 9; Px 8, 8; FW post-triangular space with 3 cells for 1 cell row, followed by 2 cells for 6, 6 cell rows; HW anal loop with cells 20, 21.

Dimensions. Head maximum width 5.6; total body length 33, abdomen 21, HW 25 long x 9.4 wide at widest point.

Diagnosis of adults. Both sexes: frons black above without metallic blue; pterothorax brown-black on dorsum shading to orange-brown on sides with a bold yellow to cream stripe on dorsal carina that does not extend onto the inter-alar membrane (extends across inter-alar membrane to base of abdomen in E. bromeliicola ); hind lobe of prothorax strongly narrowed at base; abdomen mainly orange-brown with S8–9 mostly black on dorsum; S2 with transverse carina nearly right-angled as in E. castanea (less pronounced in female). Male: genital lobe semi-erect with rounded distal margin; hamule as long and wide as genital lobe; cercus swollen subapically, rounded ventrally with 5–6 denticles. Female: vulvar lamina short, 1/4 to 1/3 the length of S9, 2-lobed (half the length of S 9 in E. bromeliicola ); sternum of S9 with posterior margin projected ventrally as in E. castanea .

Description of larva. Head. Brown, without markings. Discounting eyes and labial palpi, head shape oval in dorsal view; top of head behind eyes with a field of minute short setae on each side of midline and longer setae on lateral margins. Antenna 7-segmented, light brown, scape and pedicel short and broad, flagellum slender. Base of prementum ( Fig. 4 a) reaching to rear of forecoxa; dorsal side with 12 setae in a line on each side of central area (5 long, 7 short); 2–3 minute spinules at corner of prementum at attachment point of labial palp; labial palp with a row of 9 (8–9) long setae and a thicker terminal hook, a long seta attached behind the hook and out of line with the row of 9 setae; 8–10 minute setae between the first long seta and base of palp; distal margin of palp almost without crenulations; distal and ventral margins of palp and distal margin of prementum with slender erect hairs. Mandibles ( Fig. 4 c, d) with 4 distal teeth and 4 subapical teeth; mandibular formula: 1,2,3,4,y,a,b,d as in Fig. 4 b, c; dorsal side of each mandible with a curved line of minute setae, shown as an inset ( Fig. 4 c').

Thorax. Brown, dorsum of prothorax with darker patches; lateral margin of prothorax with 4–5 stout straight setae, bordered posteriorly by a clump of 4–5 long curved hairs.

Abdomen. No middorsal hooks; S5–9 without posterolateral teeth ( Fig. 4 b); abundant long pale orange hairs on S6–9, mostly in a subapical band across posterior end of tergite and on lateral margin; S5 without long hairs; sparse short setae scattered across dorsum of S1–9; S10 without prominent long hairs or setae. Epiproct bearing long and short setae with short thick setae especially dense on inner surface; cerci 0.6 length of epiproct, curved slightly outward toward tip, with only 1–2 straight setae on outer surface; paraprocts bearing many long hairs and short straight setae, especially on distal half; a longitudinal straight line of long straight setae on inner face.

Dimensions. (Last stage larva preserved in alcohol) Head: antenna 1.6 long; head capsule 2.3 long on dorsal midline x 4.5 wide across eyes; prementum 3.4 long x 3.5 wide; labial palp 2.3 long. Thorax: prothorax 2.0 long x 2.9 wide; pterothorax 2.9 long x 4.6 (behind coxa II); FW pad 5.8 long, HW pad 5.4; femur III 4.6 long, tibia III 5.0, tarsus III 2.3. Abdomen: without appendages 9.1 long x 4.8 wide at S6; epiproct 1.1 long x 1.1 wide at base; cerci 0.6 long; paraprocts 1.1 long.

Variation in exuviae. Dimensions: Exuviae collected from leaves of bromeliads (mean ± standard deviation; range for 10 larvae).

Head: antenna 1.6 ± 0.18; 1.2–1.8 long; head capsule 2.3 ± 0.12; 2.1–2.4 long on dorsal midline x 4.5 ± 0.18; 4.0–4.6 wide across eyes; prementum 3.1 ± 0.20; 2.8–3.5 long x 3.2 ± 0.16; 3–3.5 wide; labial palp 2.2 ± 0.09; 2.0– 2.4 long x 1.6 ± 0.04; 1.5–1.7 wide.

Thorax: prothorax 1.6 ± 0.11; 1.4–1.8 long x 2.8 ± 0.19; 2.5–3.1 wide; pterothorax 2.4 ± 0.18; 2.1–2.6 long x 3.9 ± 0.34; 3.0–4.3 wide (behind coxa II); FW pad 4.9 ± 0.29; 4.5–5.3 long, HW pad 4.5 ± 0.27; 4–4.9; femur III 5.2 ± 0.20; 4.8–5.5 long, tibia III 5.6 ± 0.19; 5.2–5.8, tarsus III 2.3 ± 0.10; 2.1–2.4.

Abdomen: without appendages 7.6 ± 0.25; 7.3–8.3 long x 4.5 ± 0.40; 4.0–5.2 wide at S6; epiproct 0.99 ± 0.05; 0.9–1.1 long x 0.96 ± 0.05; 0.9–1.1 wide at base; cerci 0.73 ± 0.03; 0.68–0.78 long; paraprocts 0.99 ± 0.06; 0.95– 1.1 long.

Diagnosis of larva. Differs from all known Erythrodiplax species, except for E. connata , by the absence of posterolateral spines on abdominal segments S6–9. Differs from E. connata by the labial palp having 8–9, instead of 7, long setae and lacking crenulations on distal margin.

Distribution and biology. To date, E. laselva is known only from the La Selva Biological Station in the Atlantic lowlands of Costa Rica. We have made almost no observations of adult E. laselva , but a study of larval ecology is underway. For several individuals observed, adults eclosed while clinging to the underside of a bromeliad leaf. Most larval exuviae were located on the east-facing side of host trees. The emergence of one male began about 06:00 local time and took about one hour until first flight. This individual flew away without first resting for a period of time with the wings spread in a horizontal position. It perched about 5 m away on another bromeliad on the opposite side of the host tree. A Mecistogaster sp. emerged from another bromeliad on the same tree later in the morning. Most of the exuviae had extensive mats of organic debris caking the long setae of the legs, thorax and abdomen ( Fig. 1 c).

Figures

FIGURE 1. Erythrodiplax laselva: a. male holotype, lateral scan; b. female, lateral scan; c. final instar larva, dorsal view.

FIGURE 2. Erythrodiplax laselva: a. male holotype, dorsum of pterothorax; b. male holotype, wings, left side, ventral view; c. Female paratype, wings, right side, dorsal view.

FIGURE 3. Erythrodiplax laselva, male holotype: a. abdominal appendages, lateral view; b. abdominal appendages, ventral view; c. vesica spermalis, dorsal view; d. vesica spermalis, lateral view; e. abdominal segment 2, lateral. E. bromeliicola male from Cuba: f. distal segment of vesica spermalis, lateral view; g. abdominal segment 2, lateral view. E. castanea male from Costa Rica: h. abdominal segment 2, lateral view. E. laselva female: i. vulvar lamina, ventral view. (Illustrations f. and g. by R. Garrison; the rest by WAH.)

FIGURE 4. erythrodiplax laselva larva: a – c from exuviae of final instar preserved in alcohol; a. prementum, dorsal view; b. right mandible, ventral view; c. left mandible, ventral view; c'. inset showing setae on dorsal side; d. apex of abdomen, posterodorsal view.