Anomalocosmoecus blancasi Schmid 1957

Anomalocosmoecus blancasi Schmid

Anomalocosmoecus blancasi Schmid, 1957:390–391.—Flint, 1980:216.

The larvae here described are associated with the adults by means of a male metamorphotype. The larvae of A. illiesi were described by Marlier (1963), and I also possess several collections from Ecuador with male metamorphotypes. The larvae of the two species are easily separated by the sharp carina around the head in A. illiesi (Figure 8) as opposed to the low broad ridge in A. blancasi (Figure 11).

LARVA.—Length to 11 mm, width 3 mm. Sclerites of head and thorax reddish-brown, muscle scars small, indistinct, and pale. Surface of head, except anteromesally, with minute asperites; meso- and metanota with asperites.

Head slightly depressed frontally, the area surrounded laterally and posteriorly with a low, broad ridge that bears the primary dorsal setae of the genae. Labrum with anterolateral brushes small and short. Mandibles with mesal brushes large; apices entire and scooplike. Maxilla with palpus normal, mesal lobes small. Labium with area between ventral rods lightly sclerotized; submental setae arising from small sclerites, submentum lightly sclerotized mesally. Gular line rather short; gula completely filling between ecdysal lines.

Pronotum with anterior margin bearing a row of short, spinelike setae, a few long setae and a very sparse, short fringe; surface with a few normal, long setae and scattered spinelike setae; transverse depression obsolete. Mesonotum with plates well developed, with a few secondary setae between primary setal areas. Metanotum with 3 pairs of sclerites well separated, multisetate; membrane with secondary setae along posterior and lateral areas. Prosternal horn not attaining apex of forecoxa; plate indistinct. Meso- and metasterna with 3–6 short setae; mesosternum with 3–6 small sclerites posteriorly. Foreleg with several short, pale, bladelike setae apically on trochanter, brush lacking; femur with 3 major ventral setae pale and bladelike, a row of short, spinelike setae on ventral margin; tibia with an irregular double row of pale blades and a serrate surface on inner margin; tarsus with inner margin serrate, and 1–2 bladelike setae; basal seta of tarsal claw ¼ the length of claw. Mid- and hind legs essentially identical; trochanter with an apicoventral bladelike seta, 3 longer, darker setae, and a few small pale setae; femora with ventral margin bearing 4 large setae and a row of smaller, spinelike setae and hairs; tibiae and tarsi with an irregular double row of short, bladelike setae and a serrate surface on inner margins; basal seta of tarsal claws ¼ the length of claw.

Abdomen with gills as shown in Figure 1. Lateral line from middle of segment 2 to middle of segment 8. Bifid processes present on segments 3–7, with 6–8 processes per segment. Chloride epithelia present ventrally on segments 3–7, anteriormost ovoid rings about 2½ times broader than long, rings broader posteriad, about 4 times as broad as long. First segment with humps well developed, ventral hump broadly transverse; setae in all areas, larger setae arising from sclerotized bases. Eighth tergum with a sparse row of mostly short setae posteriorly. Ninth tergum with tergite light brown, with numerous setae along posterior margin and continuing as an irregular row on membrane laterally; venter with 2 pairs of setae, with the mesalmost half the length of the lateral. Anal prolegs with a few, mostly short, setae on lateral plate; basal tuft of 3 setae; membranous ventral area without setae.

CASE.—Constructed of fragments of mollusk shells, flat scales of marl, and pieces of plant. Tapered posteriad and slightly curved. Posterior end narrowed with silk and fragments, with a large central opening.

MATERIAL.—Bolivia, Lago Titicaca, Copacabana Bay, 21 June 1977, Roback and Goulden, 3 larvae; same, but east end Copacabana Bay, littoral zone in Elodea and totora beds, 21–22 June 1977, C. Goulden, 1 teneral , 1 metamorphotype, 3 cases.

HABITAT.—All collections made of this species are from Lake Titicaca. The collections here reported were made either in the littoral in Elodea and Scirpus beds or by dredging at a depth of 5 m (Roback, 1980).

Collections of A. illiesi larvae are primarily from small, tumbling mountain streams in the paramo or upper yungan areas.

This is a monotypic genus known with certainty only from the provinces of Jujuy and Catamarca in Argentina at elevations of 4500–5000 meters. The larva here described from Bolivia is attributed to the genus exclusively by process of elimination. If it is not Antarctoecia, then it must be the larva of some undescribed species.

RECOGNITION.—This larva is quite distinctive. The mandibles are toothed. The thorax bears many short, dark, bladelike setae on all nota, including the membranous areas of the metanotum. The tibiae and tarsi of all legs bear 2 irregular rows of bladelike setae on their inner margins. The first abdominal segment is very hairy, though the ventral regions of the anal prolegs are without setae.