Orthotrichia, Eaton, 1973

Wells, Alice & De Moor, Ferdinand C., 2020, Hydroptilidae (Trichoptera) of Angola, a new genus, seven new species, and five new records, Zootaxa 4868 (4), pp. 495-514 : 510

Orthotrichia larvae

( Figs 16–18 )

Material examined. ANGOLA: 1 final instar larva, [CAW 758M], Moxico Province, Cuembo River, Site 6— Cuembo campsite bridge, vegetation, -13.5265, 19.27971, 02/xi/2016, I.S. Ferreira; 1 cased larva, [CAW 798S], Moxico Province, Cuando River , Site 20— Cuando River longbridge at village, vegetation, sand, -13.0923, 19.35946, 16/xi/2016, I.S. Ferreira; 1 early final instar cased larva, [CAW 803N], Moxico Province, Lungue Bungo River , Site 22— Lungue Bungo River tributary at Samanunga, vegetation, -12.9334, 18.81691, 18/xi/2016, I.S. Ferreira .

Remarks. The cases of Orthotrichia spp. larvae are usually described as ‘wheat or caraway seed’ shaped so that the cases of final instar Orthotrichia larvae are readily recognised. Only two cased larvae were collected in this study, which is not surprising, as usually the larvae in this genus are found in swiftly flowing waters, usually well attached to rocks, and possibly also to vegetation, as is likely in the many sandbed rivers in Angola. There are some records of larvae attached to Mollusc cases in lakes Kivu and Edward ( Jacquemart 1957).

Figures

FIGURES 10–19. Hydroptilidae, male genitalia. 10, 11, Hydroptila cruciata Ulmer, 1912 [CAW 797J]: 10, ventral; 11, dorsal. 12, 13, Hydroptila species [CAW 828F, 830E]: larvae in cases built with strands of filamentous algae. 14, 15, Hydroptila?cruciata [CAW 797J], larva in sand grain case and isolated larva. 16–18, Orthotrichia sp. [CAW 798S], mature fifth-instar cased larva: 16, dorsal; 17, ventral; 18, right lateral. 19, Tricholeiochiton sp. [CAW 755M], early fifth-instar cased larva; note characteristic long legs and tarsal claws.