Oecetis laustra Mosely, 1953

Wells, Alice, 2004, The long-horned caddisfly genus Oecetis (Trichoptera: Leptoceridae) in Australia: two new species groups and 17 new species, Memoirs of Museum Victoria 61 (1), pp. 85-110 : 89

Oecetis laustra Mosely

Figures 1–3, 101

Oecetis laustra Mosely in Mosely and Kimmins, 1953: 295, fig. 209. — Neboiss, 1977: 146, figs 788–791. — Neboiss, 1982: 321, figs 129–131.

Material examined. Holotype. Male, Yanchep, WA, 31°32.9'S 115°41.2'E ( BMNH).

Other material. About 180 samples in ANIC, NTM, NMV and WARI.

Diagnosis. Wings slightly mottled, fuscous-brown/grey, with short hair on veins; forewing (Fig. 1) length 4 times maximum width, footstalk of fork 1 slightly shorter than fork, posterior anastomosis almost linear, to linear, very slightly oblique; hindwing (Fig. 1) with M branched; in male genitalia, inferior appendages (Figs 2–3) broad and stout, in ventral view, a small mesial tooth at about two-thirds length, in lateral view broadly rounded above and below in basal half, distally about one-third maximum basal width; preanal lobes short, rounded.

Distribution. Widespread in Australia, in lentic and slower lotic waters, but not collected from arid central Australia (Fig. 101).

Remarks. The stouter inferior appendages distinguish O. laustra from O. atarpa and O. aeoloptera , the absence of a sharp, anteriorly directed mesial hook on the inferior appendages distinguishes it from O. pseudolaustra sp. nov. Oecetis laustra is one of the most widespread and abundant of Australian Oecetis species, although unlike O. pechana it has not been collected from the natural and artificial waterbodies of arid inland Australia. In its present concept, the species is quite variable across its range, and may eventually be demonstrated to be several species. The posterior anastomosis of the forewing is usually more or less linear, but may be slightly stepped; and in the male genitalia, the form of the mesial margin of the inferior appendages may be more or less dentate ( Mosely and Kimmins, 1953: fig. 209c, d; Neboiss, 1986: 269).