Hetaerina duplex Selys, 1853

Montes-Fontalvo, Jenilee & Stand-Pérez, Miguel, 2025, The larva of Hetaerina duplex Selys, 1853 (Odonata: Calopterygidae) with a key to known Colombian larvae species, International Journal of Odonatology 28, pp. 16-22 : 19-21

Hetaerina duplex Selys, 1853 ( Figure 2 )

Material examined

Colombia, 1♀, 9 x 2012, Quindío Department, Filandia Municipality, Barbas Bremen Nature Reserve , 4.69694444°N, - 75.65472222°W, 1650 m .a.s.l., Leg: J. Montes, L. Perez; 1♀, 13 v 2022, Risaralda Department, Pueblo Rico Municipality, Monte Bello Township, Tatamá National Park , 5.2357126°N, - 76.0871193°W, M. Stand leg.

Description of final instar larva

Coloration of head and thorax mainly brownish with dark brownish dots, legs yellowish with dark brown dots.

Head. Brownish with dark brown pattern ( Figure 2a ), with prominent and rounded posterolateral angles; antenna without setae. Labium: prementum-postmentum articulation reaching the anterior margin of mesocoxae; prementum with two setae on internal side of each lobe of ligula, external margins of ligular lobes serrate; labial palp ending in three well-developed and incurved hooks forming an 120° angle with it, median hook longest, inner one smallest; movable hook short- er than palp; inner margin of palp with small spines; four short apical palpal setae nearouter margin as in Figure 2b . Mandibles formula: L 12345 0 a(m 1234567)b/ R 12345 y ab ( Figure 2c–d ).

Thorax. Anterior margin of pronotum widely concave, with one prominent midlateral projection on each side pointing forward, posterior margin convex at middle; wing sheaths extending to posterior margin of S3; Legs: pale with three dark bands on femur, three protibial dark and faded bands; no setae or spines on femur and tibia. Abdomen: Lateral margins of S2–10 carinate, with well-developed posterolateral spine; posterolateral spine of S10 with five small spinules ( Figure 2a ); posterior margin of S10 with one mid-dorsal spine, and a group of four small spines each side of postero-ventral border ( Figure 2e–f ). Female ovipositor not reaching distal margin of S10 ( Figure 2g ) and, in ventral view, with three ventral rows of spines ( Figure 2f ); cercus conical and straight, 0.5 the length of S10. Caudal gills: lateral gills triquetral and lanceolate, with spines along lateral margins; central gill foliaceous, rounded at tip, with spines along dorsal and ventral margins about 0.7 the length of lateral gills.

Measurements (mm)

Total body length (without caudal gills): 23.1. Head: maximum length: 2.8, maximum width: 4; prementum maximum length: 4.2, prementum maximum width: 2.9; clef length: 1.7; movable hook: 1.3. Thorax and legs: inner wing pads length: 6, outer wing pads length: 5.9; femur I: 4.5; femur II: 5.8; femur III: 6.8; tibia I: 4; tibia II: 5.1; tibia III: 5.9. Abdomen: total length: 13.7; S1 length: 1.7; S2 length: 1.7; S3 length: 1.4; S4 length: 1.7; S5 length: 1.6; S6 length: 1.2; S7 length: 1.4; S8 length: 1.2; S9 length: 1; S10 length: 0.8; cerci length: 0.4; female ovipositor length: 1.8; lateral caudal gills length: 6.7, median caudal gill length: 4.9.

Diagnosis

Hetaerina duplex occurs in Colombia in the Quindío and Risaralda departments ( Figure 3 ) and larvae for the present description were collected in fast-flowing streams, where they were found partially submerged among grassy vegetation. In Tatamá National Park, where one specimen was collected, H. duplex is sympatric with H. capitalis and shares the following characters: lateral pronotal protuberance rounded, posterior border of S8–9 without row of spines on the dorsal surface, and two premental setae on each side of clef, but differs from H. capitalis in: lateral well-developed spine on each side of the lateral carina of S2–10 (one row of small spines in the lateral carina of S 8–9 in H. capitalis ) and S10 with one well-developed mid-dorsal spine on the posterior border (S10 with three small spines in H. capitalis ).

Remarks

Like other Hetaerina species inhabit lotic evironments, with or without abundant riparian vegetation ( Guillermo-Ferreira & Bispo, 2012), Hetaerina duplex is record- ed in streams and small rivers with abundant vegetation, it has been found in sympatry with H. capitalis and H. cruentata (Bota-Sierra et al., 2024) , interestingly, recent studies show that the surrounding vegetation determines the presence of the wing rubyspot (Stranding et al., 2022), the females have been seen ovipositing in dead wood inside river ponds ( Bota-Sierra et al., 2019). Its distribution is limited to Colombia and Ecuador, and its conservation status, according to the International Union for Conservation of Nature (IUCN), is classified as Least Concern ( Bota-Sierra & Palacino, 2016; Bota-Sierra & Rache, 2016).

Figures

Figure 2. Details of morphology of Hetaerina duplex. (a) Final instar larva in dorsal view; (b) labium; (c) lef mandible; (d) right mandible, both mesal view; (e) S8–10 and caudal gills, dorsal view; (f) S8–10 and caudal gills, ventral view; (g) S8–10 showing the ovipositor, lateral view.

Figure 3. Distribution of Hetaerina species in Colombia, part I.