Hydroptila larvae

(Figs 12–15)

Material examined. ANGOLA: 1 larva (no case), [CAW 750F], Moxico Province, Cuanavale River, Site 4— Outflow of Cuanavale source lake (swim area), sand, -13.0946, 18.89641, 31/x/2016, I.S. Ferreira ; 4 larvae, (3 one species, 1 another), [CAW 759D], Moxico Province, Cuando River, Site 7— Cuando River tributary, sand, -13.6029, 19.52924, 02/xi/2016, I.S. Ferreira; 1 filamentous algae case , 1 larva, [CAW 771P], Moxico Province, Cuanavale River, Site 11— Cuanavale River, at confluence, Sand, -13.1255, 18.89914, 08/xi/2016, I.S. Ferreira ; 3 larvae, 1 in algae case, [CAW 795M], Moxico Province, Cuando River, Site 20— Cuando River longbridge at village, sand, -13.0043, 19.14684, 16/xi/2016, I.S. Ferreira ; 3 larvae, 2 sand grain cases, [CAW 797J], Moxico Province, Cuando River, Site 20— Cuando River longbridge at village, sand, -13.0923, 19.35946, 16/xi/2016, I.S. Ferreira; 2 empty sand cases, 1 cased larvae, [CAW 798J], Moxico Province, Cuando River, Site 20— Cuando River longbridge at village, vegetation, sand, -13.0923, 19.35946, 16/11/2016, I.S. Ferreira; 2 empty cases, one chain diatoms and detritus, other sand grains, [CAW 805 AF], Moxico Province, Cuanavale River, Site 12— Cuanavale River tributary at confluence, aquatic and marginal vegetation, -13.447, 19.96404, 18/xi/2016, I.S. Ferreira ; 6 larvae, dark thoracic nota, [CAW 805L], Moxico Province, Cuanavale River, Site 12— Cuanavale River tributary at confluence, aquatic and marginal vegetation, -13.447, 19.9604, 18/xi/2016, I.S. Ferreira; 1 pharate adult, (too immature for identification), numerous cases, several sand grain, [CAW 828F], Huambo Province, Cubango River, Site 13— SASS handnet, gravel, -13.04443, 16.37483, 9/v/2017, I.S. Ferreira, & M. Mlambo; 3 cases , 1 larva, [CAW 846U], Huambo Province, Cubango River, Site 18— Cubango River downstream of rapids, SASS handnet, gravel, -13.33582, 16.41361, 12/v/2017, I.S. Ferreira & M. Mlambo; 1 cased larva, [CAW 862 R] Huila Province, Cubango River, Site 23—rapids, SASS handnet, stones, -14.38744, 6.28793, 16/v/2017, I.S. Ferreira & M. Mlambo .

With the exception of the pharate adult identified as Hydroptila cruciata and, possibly, the associated sand grain cased larvae, the immature stages of Hydroptila species cannot be identified to species. Most of the larval cases in the above listed samples were constructed using filaments of unidentified green algae, probably also the food source of the larvae.