Acanthagrion lancea Selys

Abstract

Acanthagrion lancea Selys Description of last instar larva (figs. 8–14). Head. Almost two times as wide as long, posterolateral margins slightly concave, posterior angle with several short spines (Fig. 8). Posterior margin concave. Seven spines on inferior border of eyes near maxillae. Antennae 7 -segmented, the third antennomere the longest. Labium reaching second coxae; prementum almost 1.4 times as long as wide; anterior margin convex and slightly crenulated, with 5 or 6 premental setae (2 + 1 or 3), the inner ones usually shorter than the others or the same size than the others; lateral margin with usually 8 spiniform setae (Fig. 9). Labial palp with four setae; outer half of distal margin with three very small teeth, inner half with three teeth and a curved end hook; movable hook slender and sharp; inner margin of palp slightly crenulated (Fig. 10). Mandibular formula L 1 + 2 3 + 4 5 0 a b, R 1 + 2 3 4 5 y a (Figs. 11 a,b). Thorax. Wing pads nearly parallel, the external reaching middle of S 4. Legs pale; femora with a row of spiniform setae on the dorsal and lateral surface; tibiae with sparse, long and delicate setae on the external surfaces, apical ends with a delicate group of setae on the internal surface; tibiae II and III with two row of spiniform setae on the internal surface; tarsi with two rows of setae on the ventral surface. Abdomen. Cylindrical. Light brown. Dorsal spines on the tergite surface S 4–10 in female and 5–10 in male. A row of lateral spines on S 2–10. Male gonapophyses sharply pointed and divergent with a row of 5 spines, surpassing mid-length of S 10 (Fig. 12). Female gonapophyses exceeding posterior margin of sternite 10, lateral valvae sharply pointed with a ventral row of 5 robust spiniform setae and 4 lateral spines (Fig. 13). Male cerci as in Figure 12, female cerci as in Figure 13. Caudal lamellae lanceolate, with width/length ratio 0.13 (Fig. 14). Dorsal margin of lateral caudal lamella with about 40 setae; ventral margin with about 15 setae. Tracheation as in Figure 14. Measurements. (mm). Total length (without caudal lamella) (N= 3): 10.23 [9.83–10.96]. Head: maximum length: 1.44 [1.42–1.48]; maximum width: 2.16 [2.10–2.27]. Prementum: maximum length: 2.16 [2.10–2.27]; maximum width: 1.53 [1.48–1.59]. Thorax: femur I: 1.54 [1.49–1.57]; femur II: 1.86 [1.79–1.99]; femur III: 2.47 [2.38–2.52]; tibia I: 1.78 [1.75–1.80]; tibia II: 2.14 [2.09–2.18]; inner wing pads maximum length: 3.75 [3.73– 3.78]; outer wing pads maximum length: 3.49 [3.29–3.68]. Abdomen: total length: 6.05 [5.64–6.77]; S 9 length: 0.35 [0.29–0.39]; S 10 length: 0.37 [0.34–0.41]; cerci length: male (N= 1): 0.14, female (N= 2): 0.11; female gonapophyses length (N= 2): 0.80; male gonapophyses length (N= 1): 0.27. Lateral caudal lamella (N= 1): maximum length: 6.36. Specimens examined. 3 exuviae (1 male and 2 females reared). BRAZIL: Espírito Santo State, Estação Biológica de Santa Lúcia, Lagoa Molino, 24.vii. 2009, leg. D. Anjos-Santos, C. Carriço, J.M. Costa & T. C. Santos (1 3) [emerged in laboratory: 02.viii. 2009]. Rio de Janeiro State, Rio de Janeiro, São Cristóvão, Horto FAHUPE, Col. 15, Estação 3, nº15, 20.xi. 1985, leg. J. R. Pujol-Luz (1 Ƥ) [emerged in laboratory: 13.i. 1986]; 27.i. 1986, leg. J.R. Pujol-Luz (1 Ƥ) [emerged in laboratory: 17.ii. 1986].Published as part of Anjos-Santos, Danielle, Carriço, César, Costa, Janira Martins & Santos, Tatiana Chrysostomo, 2011, Description of the final instar larvae of Acanthagrion gracile (Rambur) and Acanthagrion lancea Selys (Odonata: Coenagrionidae), pp. 44-50 in Zootaxa 2832 on pages 45-46, DOI: 10.5281/zenodo.20358