Pelosoma sp. (Archangelsky, 1997)

Rodriguez, Georgina & Archangelsky, Miguel, 2023, Larval chaetotaxy and morphometry of Megasternini: Cercyon (Paracercyon) Seidlitz, Cryptopleurum Mulsant and Pelosoma Mulsant (Coleoptera: Hydrophilidae), Zootaxa 5318 (1), pp. 45-66 : 61

Pelosoma sp. third- instar larva

Morphometry. Measurements and ratios in Table 1 .

Chaetotaxy. Head capsule ( Figs. 57–59 ). Frontale without secondary sensilla and lacking egg-bursters; FR6 much shorter, gFR1 with eight short setae. Each parietale with eight secondary sensilla: dorsally two setae near PA7, one seta close to PA8, one short seta between antennal socket and PA9, one pore between PA19 and PA20, one seta near PA11; ventrally two short setae on outer margin between PA15 and PA18; seta PA8 proportionally shorter, setae PA16, PA20, PA22 and PA26 proportionally longer. Antenna ( Fig. 60 ). Without secondary sensilla, sensory appendage (SE1) proportionally shorter; gAN on A3 with a group of at least six sensilla. Mandibles ( Figs. 61–62 ). Each mandible with three short secondary setae, two on basal outer face, behind MN1, third one minute, behind pore MN4. Maxilla ( Figs. 63–65 ). Without secondary setae; setae of gMX2 apparently simple; seta MX 6 shorter than MX 5; seta MX 23 proportionally shorter. Labium ( Figs. 58 , 66 ). Without secondary sensilla.

Figures

FIGURES 57–62. Pelosoma sp., third instar larva. (57) head capsule, dorsal view; (58) head capsule, ventral view; (59) clypeolabrum, dorsal view; (60) antenna, dorsal view; (61) mandible, dorsal view; (62) mandible, dorsal view. Scale bars, Figs. 57–58: 0.1 mm; Figs. 59–62: 0.025 mm.

FIGURES 63–66. Pelosoma sp., third instar larva. (63) right maxilla, ventral view; (64) right maxilla, dorsal view; (65) left stipes, dorsal view; (66) labium, ventral view. Scale bars: 0.025 mm.