Cosmodela aurulenta aurulenta (Fabricius, 1801)

Putchkov, Alexander V. & Markina, Tetiana Yu., 2020, The description of the tiger beetle larvae of Cosmodela aurulenta (Fabricius 1801) (Coleoptera, Cicindelidae), Zootaxa 4859 (4), pp. 537-544 : 538-540

Cosmodela aurulenta aurulenta (Fabricius, 1801)

Description of third instar larva. Measurements: HL = 2.10–2.25 (2.14) mm; HW = 3.62–3.84 (3.68) mm; PNL = 2.20–2.35 (2.32) mm; PNW = 3.75–3.94 (3.82) mm.

Head above almost black with faint lustre (sometimes greenish-blue). Most part of head below light brown, but almost black on anterior margin. Maxillae light brown (labium and antennae darkened) but apical region of mandibles and antennae almost black. Maximum width of head on level of stemma I. Nasale transverse, wider base of mandible and slightly rounded at apex, with longitudinal grooves at base. Lateral lobes small, lateral plates below lateral lobes widened, almost rectangular. Disk of clypeus almost smooth. Setae thin, long and acute on apexes (but some of them near stemmata I and II slightly obtuse). All setae reddish-transparent.A1 with 5–6, A2 with 8–10 long setae. Length ratio of antennae (starting with the first) = 1.5:1.8: 1.2:1.0. Galea distinctly longer than maxillary palpus ( Fig 4 ). Maxillae slender, stipes with 1 bristle on internal margin base and almost equal in length to galea. LP1 with three shortened spine-liked projections and three long lateral setae. LP2 with one seta near middle. Epicranial suture distinct, longer than diameter of fourth antennomere.

Pronotum almost black. Setae thin, reddish-transparent. Marginal setae acute on apexes, setae on disk of PN slightly obtuse). PNa wide and with slightly rounded apices; swellings of PNa and callous elevations of PN distinct ( Fig. 1 ). PN1 with 8–10 setae, PNm with 4–5 setae, ridge of PNa with 2 setae. Legs light brown, partly darkened above and habitually similar to those of other Cicindelinа larvae.

Sclerotized areas of abdomen distinct. T3 almost rectangular (angles rounded) and with 10–14 reddish-transparent setae. Hypopleuron consisting of one large sclerites and 3-4 small ones (type I). CT5 and AT5 almost semicircular and not jointed on inner margin ( Fig. 2 ); apex of MH almost reached middle of AT5; LCT5 with 6-7 long setae; CT5 with 20-25 stout setae (similar to those of inner hook) and some thin small setae on posterior margin ( Fig. 2 ); MH with three long setae but upper seta (near middle of MH) slightly displaced and directed nearly upward ( Fig. 2 ), 4.0 times longer than wide on base; IH directed up, its central spine in 3 times shorter lateral setae; IH 0.4 times as long as MH, 2.2-2.4 times longer than wide. TE9 with 6–7 setae (four from them on middle shorter) ( Fig. 4 ). EU9 with two groups of four setae each ( Fig. 3 ). PY with 26-28 setae dorsally and 10-12 thin setae ventrally; apex of PY with 18-20 stout and long setae ( Fig. 3 ) .

Description of second instar larva. Measurements: HL = 1.25 mm; HW = 2.20 mm; PNL = 1.25 mm; PNW = 2.40 mm.

Head above almost black with faint greenish lustre. Antennae and apical parts of mandibles brown, other appendages light brown. Setae thin, acute (only some setae near stemmata I and II obtuse). Most setae reddish transparent, but those on appendages brown. Nasale transverse, apex slightly rounded. A1 with five long setae and A2 with six long setae. Galea slightly longer maxillary palpus. Apex of LP1 with two long lateral setae and three spinelike projections; LP2 with one seta slightly below middle. Epicranial suture distinct.

PN almost black with faint greenish-bronzed lustre. PNa dark brown, slightly rounded and directed forward; setae of PN disk light brown, thin, some of them obtuse, others acute; marginal setae reddish-transparent. Swellings of PNa and callous elevations of PN distinct. PN1 with 8–10 setae, swellings of PNa with 2 setae. Legs brown above, but light brown below.

Sclerotized areas of abdomen distinct, light brown. Third abdominal tergite with 7–8 setae. Sclerites of hump divided, not jointed on inner margin; apex of MH extends beyond middle of AT5; MH 3.3 times longer than wide, with two long setae but upper seta slightly displaced and directed up; IH 0.4 times as long as MH; central spine of IH 0.7 times as long as lateral setae; CT5 with 18–20 stout setae and 6–7 small setae on posterior margin; LCT5 with four long setae. TE9 with seven setae (four of them on middle shorter and 0.3 times as long as lateral setae). EU9

with two groups of four setae. PY with 20 setae dorsally (those near 10 are stout) and seven smaller setae ventrally; apex of PY with 17 setae.

Description of first instar larva. Measurements: HL = 0.85 mm; HW = 0.75 mm; PNL = 0.87 mm; PNW = 1.42 mm.

Head dark brown. Antennae and apical part of mandibles brown. Other appendages light brown. Setae reddishtransparent, long and obtuse. A1 bare, second and third with two setae apically. Galea slightly longer than maxillary palpus. LP1 with three spine-like projections, LP2 with one seta distinctly below middle.

PN brown with anterolateral angles light brown; anterior margin of PN almost straight ( Fig. 5 ); swellings of PNa and callous elevations of PN distinct; setae on anterior margin and inside PN obtuse; other marginal setae acute. PN1 with five setae, excluding marginal setae ( Fig. 5 ). Legs light brown above.

Sclerotized areas of abdomen slightly chitinized and pale brown. T3 with three setae. MH distinctly curved after middle ( Fig. 6 ), with one seta on middle; IH 0.6 times as long as MH; central spine of IH large; CT5 bare; LCT5 with one long seta; AT5 with four setae ( Fig. 6 ). TE9 with 6 setae. EU9 with two groups of three setae on posterior margin ( Fig. 8 ). PY with eight setae dorsally and bare ventrally; apex of PY with 12 setae ( Fig. 7 ).

Distribution and ecological peculiarities. Cosmodela a. aurulenta is a common species in Bali Island. Adults and larvae were collected along the shores of small rivers and streams (usually in deep clefts), commonly on claysand or sand soils without or with very sparse vegetation (but near forests) ( Fig. 9 ). Larvae usually aggregated at moist sand loose soil. The depth of larval burrows vary from 8–10 cm (first and second instar larvae) to 15–18 cm (third instar larvae). Interesting hidden larval burrow plugs and their function were observed by Lin & Okuyama (2013) in the similar species Cosmodela batesi , whose larval III instar differences are compared in Table 1 here.

The habitat of Cosmodela aurulenta in other regions has not been recorded, but presumably adults occur near forest streams like some related species (for example, Cosmodela virgula Fleutiaux, 1893 ) ( Acciavatti & Pearson 1989).

Figures

FIGURE 9. The habitats of adults and larvae of Cosmodela aurulenta (red arrows indicate locations of larvae burrows).

FIGURES 1–8. Features of third and first instar larvae of Cosmodela aurulenta: 1. Pronotum, III instar (left half); 2. Hump, III instar (right part, dorsal view); 3. Ninth abdominal segment and pygopod, III instar (ventral view); 4. Ninth abdominal segment and pygopod, III instar (dorsal view); 5. Pronotum, fI instar (left half); 6. Hump, I instar (left part, dorsal view); 7. Ninth abdominal segment and pygopod, I instar (dorsal view); 8. Ninth abdominal segment and pygopod, I instar (ventral view); (scale bar = 1.0 mm).