Hydropsyche dolosa Banks 1939

Prommi, Taeng On, 2016, Descriptions of larvae of four species of Hydropsyche (Hydropsychidae: Trichoptera) from Thailand, Zootaxa 4158 (4), pp. 577-591 : 578

Hydropsyche dolosa Banks 1939

( Figs. 1–9 )

Larva: Total length 13.0–14.0 mm (n = 10). Overall body shape as usual in Hydropsychidae ( Fig. 1 ). Head darkbrown with yellow stripe on midline appearing to be continuation of longitudinal stripe on thoracic plates.

Head: Head capsule length 1.19–1.33 mm; width, 1.02–1.05 mm (n = 10). Dorsum of head light-brown with yellow stripe on midline wider anteriorly ( Fig. 2 ). Lateral portion of head with yellow band connecting yellow areas around eyes reaching toward back of head; light-brown muscle scars posteriorly near posterior areas of head. Frontoclypeus with anterior margin slightly concave, with pairs of setae #1, #2, and #3 extending beyond anterior margin ( Fig. 2 ). Head ventrally with transverse stridulatory lines on either side of ventral midline, extending about 2/3rds of length of head capsule; light brown region lateral of stridulatory lines surrounded by yellow ( Fig. 3 ). Labrum light brown, slightly convex posteriorly; bearing well-developed, lateral, golden brown, pectinate setae and stout setae on dorsal surface ( Fig. 4 ). Mandibles golden brown, asymmetrical, right mandible with 1 apical and 3 mesal teeth, left mandible with 2 apical and 3 mesal teeth and with mesal tuft of hairs; lateral surfaces of mandibles with scattered, long, setae ( Fig. 5 ). Submentum with shallow median cleft; maxillae with long, black setae and stout setae laterobasally ( Fig. 3 ). Anterior ventral apotome broadly triangular, posterior ventral apotome minute, triangular ( Fig. 3 ).

Thorax: Nota brown with very conspicuous yellow stripe on midline appearing to be continuation of longitudinal stripe on head. Nota covered with long, dark and clear, erect, truncate peg setae, intermixed with tapered setae on surface and anterior margin of each notum ( Fig. 7 ). Prosternite light-brown, transverse, narrow, with broad dark band posteromesally; with pair of large, light brown, posterolateral sclerites ( Fig. 6 ). Foretrochantin deeply forked ( Fig. 1 ). Forelegs with feather-like setae on posterior surfaces of coxae; trochanters and femora with long feather-like setae on ventral surfaces and with long setae; tibiae and tarsi with stout setae ( Fig. 8 A). Mid- and hind legs similar in size, shape, and structure; with stout setae on posterior surfaces of femora; tibiae and tarsi with scattered setae in ventral margins ( Figs. 8 B, 8C). Mesosternum with one pair of singlestemmed gills and metasternum with 2 pairs of single-stemmed gills; gills bearing approximately 50 lateral filaments.

Abdomen: Abdominal segments densely covered with dark, hair-like setae and club-like hairs ( Fig. 1 ). First sternum 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 arising from common base ( Fig. 1 ). Sternum VIII with pair of half-moon sclerites ( Fig. 9 ). Sternum IX with pair of spine-bearing plates, with spines emanating from prominent sockets. Tergum IX with small lateral sclerites ( Fig. 9 ) and pair of large dorsal sclerites. Anal prolegs each with bent claw and cluster of long bristles, without spike-like setae on ventral surface.

Material examined. THAILAND: RATCHABURI Prov.: Huai Nueng stream from Phachi watershed , 140 m . 13°32.135'N, 099°17.842'E, 26-x-2013, Prommi, 80 larvae, 10 pupae, 5 male pupae, 5 male adults; Huai See stream from Phachi watershed , 170 m . 13°34.078'N, 099°15.495'E, 4-xii-2013, Prommi, 27 larvae, 5 male adults; Huai Phark from Phachi watershed , 183 m . 13°30.241'N, 099°15.889'E, 5-xii-2013, Prommi, 10 larvae, 3 pupae; Phachi Nueng stream from Phachi watershed , 160 m . 13°48.379'N, 099°19.152'E, 5-xii-2013, Prommi, 40 larvae, 6 male pupae, 5 male adults; Phachi Song stream from Phachi watershed , 155 m . 13°31.017'N, 099°27.449'E, 5-xii- 2013, Prommi, 32 larvae; Phachi Sarm stream from Phachi watershed , 123 m . 13°34.275'N, 099°21.778'E, 5-xii- 2013, Prommi, 42 larvae, 3 male pupae, 2 male adults; KANCHANABURI Prov.: Huai Kayeng , 244 m . 14°36.224'N, 098°34.822'E, 6-xii-2014, Prommi, 43 larvae, 8 male pupae, 7 male adults; Huai Lin Thin , 116 m . 14°34.445'N, 098°50.039'E, 8-xii-2014, Prommi , 9 larvae, 1 male pupa.

Figures

FIGURES 1 ― 6. Larva of Hydropsyche dolosa Banks 1939: 1, larval habitus, right lateral; 2, head, dorsal; 3, head, ventral; 4, labrum, dorsal; 5, mandibles, ventral; 6, prosternum, ventral.

FIGURES 7 ― 9. Larva of Hydropsyche dolosa Banks 1939: 7 A, pronotum, dorsal; 7 B, mesonotum, dorsal; 7 C, metanotum, dorsal; 8 A, right foreleg, right posterolateral; 8 B, right midleg, right posterolateral; 8 C, right hind leg, right posterolateral; 9, sterna VIII and IX and anal prolegs, ventral.