Tasiagma eremica Neboiss

Wells, Alice, 2011, The Trichoptera of Lord Howe Island, including 3 new species, larvae and keys, Zootaxa 2987, pp. 45-55 : 51

Tasiagma eremica Neboiss

( Figs 17, 20, 21 )

Tasiagma eremica Neboiss, 1986a: 219 , figs 26–28

Material examined. 3 males, Erskine Creek, Erskine Valley, 22.xi.1996 (sweep net), A. Wells; numerous larvae (all stages), pupae, Soldiers Creek (lower reaches), 23.xi.1996, A. Wells; 5 males, Soldiers Creek (upper), 24.xi.1996, A. Wells; 9 larvae Erskine Creek, Erskine Valley, 27.xii.2001, A. Wells.

Cased larva ( Figs 20, 21 ). The coarse sand-grain/small stones cases of Tasiagma eremica are typical of the genus. The larval head ( Fig. 17) is sharply angled to present a flat face, the eyes bulge prominently; in dorsal and lateral views, the anterior angles of the prothorax are produced anteriorly, the apical angles rounded ( Fig. 17).

Remarks. The larvae of this species have the antero-lateral angles of the pronotum produced, but their apical angles rounded. Thus they are somewhat intermediate in form between the larva of Tasiagma and Tasimia Mosely, 1936 , as illustrated by Dean et al. (2004: 123), suggesting that separation of Tasiagma and Tasimia , which is based on presence in the male of Tasiagma ciliata Neboiss, 1977 , of forewing fork 3, may be unjustified. This suggestion is supported also by the fact that the female wing of the type species of Tasimia , T. palpata Mosely, 1936 , has forewing fork 3 present. The 2 genera are probably synonymous. Larvae of T. eremica were abundant in the Island streams in late November 1996 and late December 2001, but in late December 2007 none were found despite intensive searching; I am unable to explain the 2007 situation.

Figures

FIGURES 20, 21. Tasiagma eremica Neboiss, 1986, final instar cased larvae in right lateral and dorsal views. FIGURES 22 – 24. Symphitoneuria neboissi sp. n. cased larvae, dorsal views: 22, early instar mixed sand and detritus case; 23, final instar sand case; 24, flattened leaf fragment case.