Hydropsyche camillus Malicky & Chantaramongkol 2000

(Figs. 19—27)

Larva: Total length 10.0—11.0 mm (n = 10). Overall body shape as usual in Hydropsychidae (Fig. 19). Head yellow to dark brown, with dark muscle scars in posterior 1/5th. Nota light brown, each with posterolateral muscle scars.

Head: Head capsule length 1.02—1.05 mm; width, 0.85—0.94 mm. Dorsum of head dark brown, with two or three distinct yellow marks on frontoclypeus: T-shaped mark anteriorly and circular mark posteriorly or transverse band anteriorly, small spot in middle, and circular mark posteriorly (Fig. 20). Frontoclypeus with anterior margin strongly convex, with setae #1, #2, and #3 extending beyond anterior margin (Fig. 20). Head with moderately long, erect, truncate peg setae; with tapered setae on dorsal and lateral regions of anterior 3/4ths. Frontoclypeus with few setae or no brush of setae; with truncate peg setae anterolaterally (Fig. 20). Head ventrally dark-brown with stridulatory lines in anterior 3/4ths (Fig. 21). Labrum light-brown; elliptical in dorsal view; bearing welldeveloped, lateral, golden-yellow pectinate setae and stout setae on dorsal surface (Fig. 22). Mandibles darkbrown, right mandible with 2 apical and 2 mesal teeth, left mandible with 2 apical and 3 mesal teeth and welldeveloped mesal setal brush (Fig. 23). Submentum light-brown, with deep anteromesal cleft, anterior margins on either side of cleft with long setae. Anterior ventral apotome broadly triangular, posterior ventral apotome small, triangular (Fig. 21).

Thorax: Nota brown with darker muscle scars laterally. Pronotum with numerous, erect, truncate peg setae and long, tapered setae (Fig. 25 A). Meso- and metanota with numerous scale hairs and with scattered truncate peg setae (Figs. 25 B, 25C). Prosternite brown, transverse, narrow, with broad dark transverse band along posterior margin and pair of fine dark transverse bands anterolaterally; with pair of large posterolateral sclerites brown on mesal 2/3rds and pale laterally (Fig. 24). Foretrochantin deeply forked (Fig. 26 A). Forelegs each with numerous feather-like setae on posterior surface of coxa; trochanter with long, feather-like setae on ventral margin; femur with row of long, dark, spike-like setae, mingled with feather-like setae on ventral margin and few, short, dark, setae on external surface (Fig. 26 A). Mid- and hind legs similar in size, shape, and structure, each with feather-like setae on posterior surface of femur (Fig. 26 B, 26C). Mesosternum with one pair of single-stemmed gills and metasternum with 2 pairs of single-stemmed gills; gills each bearing approximately 22 lateral filaments.

Abdomen: Abdominal segments densely covered with dark, club-like hairs (Fig. 19). Sternum I with 2 pairs of bifid-stemmed gills. Segments II—V each with one pair of median gills. Segments II—VII each with one pair of lateral gills each arising from common base (Fig. 19). Sternum VIII with pair of small, triangular sclerites bearing spike-like setae. Sternum IX with pair of large, triangular sclerites bearing spike-like setae emanating from prominent sockets. Tergum IX with small lateral sclerites (Fig. 27) and pair of large dorsal sclerites. Anal prolegs each with bent claw and cluster of long bristles, spike-like setae present on dorsal and ventral surfaces (Fig. 27).

Material examined: THAILAND: KANCHANABURI Prov.: Huai Kayeng, 244 m . 14°36.224' N, 098°34.822' E, 6-xii-2014, 126 larvae, 8 male pupae, 27 male adults; Huai Lin Thin, 116 m. 14°34.445' N, 098°50.039' E, 8-xii-2014, 9 larvae, 4 pupae; Huai Pakkok, 246 m. 14°39.518' N, 098°32.237' E, 12-iv-2015, 195 larvae, 16 male pupae; Huai U-Long, 191 m. 14°47.126 N, 098°40.589' E, 12-iv-2015, 92 larvae, 6 male pupae, 12 male adults. All material leg. Prommi.