Litocladius chavarriai, Mendes, Humberto F., Andersen, Trond & Hagenlund, Linn K., 2011

Mendes, Humberto F., Andersen, Trond & Hagenlund, Linn K., 2011, New species and records of Antillocladius Saether and Litocladius Mendes, Andersen et Saether from Brazil and Costa Rica (Chironomidae: Orthocladiinae), Zootaxa 2915, pp. 39-51 : 46-48

Litocladius chavarriai sp. n.

( Figs 12–17 )

Type material. Holotype male, COSTA RICA: Alajuela Province, Alfaro Ruiz Cantón, near Zarcero, 10°10'29''N 84°24'40''W, 1566 m a.s.l., 15.viii.2010, net, T. Andersen, H.F. Mendes & L.K. Hagenlund ( ZMBN). Paratypes: 1 male as holotype ( MZUSP); 2 males as holotype except for 17.viii.2010 ( ZMBN).

Etymology. Named after Edgar Alonso Chavarría Solano, the owner of the land where the species was taken, for all his help and kindness during our stay in Costa Rica.

Diagnostic characters. The species groups with L. floripa and L. neusae sp. n. based on the presence of spines on third palpomere; it can be separated from both by the presence of setae on M3+4, Cu1 and An, and by having 80– 140 setae in cell m1+2.

Description. Male (n = 3–4, except when otherwise stated). Total length 2.04–2.34, 2.17 mm. Wing length 1.28–1.62 (2) mm. Total length / wing length 1.36–1.60 (2). Wing length / length of profemur 2.34–2.35.

Coloration. Dark brown, thorax without distinct pattern.

Head. AR 0.73–0.85. Ultimate flagellomere 277–367 µm long. Temporal setae 9–12, 11 including 4–6, 5 inner verticals; 2–3, 3 outer verticals; and 3–5, 4 postorbitals. Clypeus with 5–7, 6 setae. Tentorium, stipes, and cibarial pump as in Figure 12 . Tentorium 107–120, 116 µm long; 18–23, 21 µm wide. Stipes 98–118 µm long, 29–36 (2) µm wide. Palp segment lengths (in µm): 18–23, 21; 34–41, 38; 104–120, 110; 107–120 (2); 111–143 (2). Third palpomere ( Fig. 13 ) with 3–4, 4 sensilla clavata subapically, longest 9–14, 12 µm long; and with 1–2 apical spines, 25–36, 30 µm long.

Thorax ( Fig. 14 ). Antepronotum with 3–5, 4 setae. Dorsocentrals 10–16, 12; acrostichals 13–21, 16, composed of 3–5, 4 anterior strong decumbent, 2–4, 3 weak hair-like, and 7–14, 9 posterior scalpellate; prealars 4–6, 5; supraalar 1. Scutellum with 7–10, 8 setae, uniserial.

Wing (n = 2) ( Fig. 15 ). VR 1.34–1.39. Costal extension 72–79 µm long. Brachiolum with 1 seta, costal extension with 10–16 non-marginal setae, R with 11–17 setae, R1 with 12–13 setae, R4+5 with 22–28 setae, M1+2 with 34– 47 setae; M2+3 with 11–21 setae, Cu1 with 4–12 setae, An with 9–11 setae; cell m r4+5 with 134–247 setae; m1+2 with 80–143 setae; m3+4 with 22–52 setae, remaining cells and veins bare. Squama with 7–9 setae.

Legs. Spur of fore tibia 41–50 (2) µm long; spurs of mid tibia 27–38 (2) µm and 20–27 (2) µm long; spurs of hind tibia 16–24, 21 µm and 43–52, 48 µm long. Width at apex of fore tibia 29–36, 33 µm; of mid tibia 31–36 µm; of hind tibia 34–45, 41 µm. Comb with 10–15, 11 setae; longest 27–36, 32 µm; shortest 20–25, 23 µm long. Lengths and proportions of legs as in Table 3.

Hypopygium ( Figs 16–17 ). Tergite IX covered with microtrichia; laterosternite IX with 3–5, 4 setae. Anal point triangular; 68–72, 70 µm long; 29–35, 33 µm wide at base; 2–4, 3 µm wide at apex; with 14–25, 22 setae. Phallapodeme 82–93, 85 µm long; transverse sternapodeme 95–118, 104 µm long. Virga 86–98, 92 µm long. Gonocoxite 141–170, 153 µm long. Gonostylus 91–102, 94 µm long; megaseta 6–8, 7 µm long. HR 1.53–1.83, 1.63. HV 1.74–2.33, 2.29.

Biology and distribution. The males were collected at about 1500 m altitude in a mountainous area with steep hillsides. The area was originally covered with cloud forests, but is now used for cabins and pastures. Several large evergreens have been planted close to the collecting site, but the native vegetation is apparently slowly returning to the area and the trees and soil are covered with mosses and bromeliads. The larva of Litocladius mateusi is semiterrestrial living in mosses and the larvae of L. chavarriai n. sp. might well be found in similar circumstances.

The genus Litocladius was previously known only from southern and south-eastern Brazil; the new record extends its known range to Central America.

Figures

FIGURES 12 – 17. Litocladius chavarriai sp. n., male. 12 — tentorium, stipes and cibarial pump; 13 — third palpomere; 14 — thorax; 15 — wing; 16 — hypopygium, dorsal aspect; 17 — hypopygium with anal point and tergite IX removed, dorsal aspect to the left and ventral aspect to the right.