Hydromanicus abiud Malicky & Chantaramogkol, 1993

Prommi, Taeng On & Permkam, Surakrai, 2015, Larvae of Hydromanicus (Insecta: Trichoptera: Hydropsychidae) from Thailand, Zootaxa 3914 (4), pp. 467-482 : 472

Hydromanicus abiud Malicky & Chantaramogkol, 1993

( Figs. 19–38 )

Larva: Total length 17.0–17.5 mm (n=10). Overall body shape typical for Hydropsychidae .

Head: Head capsule length, 1.53–1.62 mm; width, 1.36–1.45 mm. Dorsum of head brownish, with yellow ring around each eye ( Fig. 16 ). Dorsal and lateral portions of head covered with long, black, truncate peg setae, with tapered setae in anterior three-fourths ( Fig. 33 ). Entire frontoclypeus covered with same setae; frontoclypeus with anterior margin strongly convex ( Fig. 20 ). Ventral surface of head brownish, with stridulatory lines in anterior half; posterolaterally paler with group of muscle scars ( Fig. 21 ). Labrum brown; rounded in dorsal view; bearing welldeveloped, lateral, golden-yellow, pectinate setae and dorsal long, stout, dark setae, with one pair of longer, dark anteromesal setae ( Fig. 22 ). Mandibles dark-brown to black with 2 apical and 3 mesal teeth, left mandible with well-developed setal brush; outer surfaces of both mandibles with scattered setae ( Fig. 23 ). Submentum darkbrown; lacking anteromesal cleft; anterior margin concave; anterior margin and lateral area with short and long, dark setae ( Fig. 24 ). Anterior ventral apotome broadly triangular; posterior ventral apotome small, triangular ( Figs. 21, 24 ).

Thorax: Nota brownish, covered with same setae as on dorsum of head ( Figs. 26–28 , 34 ). Pronotum with weak posterior sulcus. Prosternite brown; broadly transverse; dark band along posterior margin; with pair of large, paler sclerites posterolaterally ( Fig. 25 ). Foretrochantin forked; dorsal branch as long as ventral branch, with stout setae on ventral branch ( Fig. 29 ). Forelegs stouter than other legs, each with femur widened; posteromesal surface of coxa, trochanter, and femur densely covered with feather-like setae; femur with long and spike-like setae in anterior surface and ventral margin; tibia and tarsus each with rows of short, stout setae ( Figs. 29 , 35–36 ). Mid- and hind legs similar in size, shape, and structure; with dense spike-like setae and stout setae on mesal surfaces of coxae through tarsi; each with row of feather-like setae on ventral margin ( Figs. 30–31 ). Mesosternum with one pair of gills; metasternum with 2 pairs of gills; gills consisting of central stem bearing many lateral filaments.

Abdomen: Abdominal segments with dense dark, club-like hairs of various shapes ( Fig. 37 ). First sternum with 2 pairs of gills with adjacent bases. Segments II–VI each with 2 pairs of lateral gills and 1 pair of median gills ( Fig. 38 ). Sternum VIII with pair of small, subtriangular sclerites bearing spike-like setae. Sternum IX with pair of large, triangular sclerites bearing spike-like setae emanating from prominent sockets ( Fig. 32 ). Tergum IX with pair of small lateral and dorsolateral sclerites. Anal prolegs each with bent claw and cluster of long bristles, spike-like setae present on dorsal surface ( Fig. 19 ).

Material examined: THAILAND. RANONG Prov.: Ngao National Park, Ngao Waterfall; 50 m. 09°51' N, 098°37' E, 9-x-2004, Prommi, 2 larvae; same locality, 02-iv-2005, Prommi, 18 larvae. KRABI Prov.: Khaopanombenja National Park, Huai To Waterfall; 26 m. 08°14' N, 098°54' E, 6-x-2004, Prommi, 2 larvae. SATUN Prov.: Thaleban National Park, Ranee Waterfall, 94 m. 06°42' N, 100°10' E, 12-xi-2004, Prommi, 10 larvae, 2 male pupae, 2 male adults.

Figures

FIGURES 19 – 25. Larva of Hydromanicus abiud: 19, larva, right lateral; 20, head, dorsal; 21, head, ventral; 22, labrum, dorsal; 23, mandibles, dorsal; 24, submentum and anterior ventral apotome, ventral; 25, prosternum, ventral.

FIGURES 26 – 32. Larva of Hydromanicus abiud: 26, pronotum, dorsal; 27, mesonotum, dorsal; 28, metanotum, dorsal; 29, right pleuron, foretrochantin (arrow), and foreleg, right lateral (posterior); 30, right midleg, right lateral (posterior); 31, right hind leg, right lateral (posterior); 32, sterna VIII and IX, ventral.

FIGURES 33 – 38. SEM images of Hydromanicus abiud: 33, setae on dorsum of head, dorsal; 34, setae on pronotum, dorsal; 35, setae on right forecoxa, ventral; 36, inner face of right foreleg, ventral; 37, setae on abdominal segment III, dorsal; 38, ventral sublateral gills of abdominal segment IV, ventral.

FIGURES 13 – 18. SEM images of Hydromanicus malayanus: 13, head, dorsal; 14, setae on surface of head, dorsal; 15, setae on abdominal segments, dorsal; 16, setae on abdominal segment III, dorsal; 17, ventral submesal abdominal gills of segment I, ventral; 18, sterna VIII and IX, ventral.