Hydroptila helicina Flint 1991

Hydroptila helicina

This species, H. spirula Bueno-Soria, and H. argentinica Flint, form a very distinctive group based on the spiral apex of the phallus. From both, H. helicina is to be recognized by the very slender basal portion of the apical section of the phallus, and the very broad apex of the clasper. I can detect no differences between females taken with H. spada, new species, and H. helicina. Perhaps one is incorrectly associated, or alternatively the females of the two species are so similar as to be inseparable. I have no way to resolve this question and so describe the female under H. helicina but must warn that the association could be incorrect.

ADULT.—Length of forewing, 2.5–3.5 mm. Color in alcohol, pale brown. Seventh sternum bearing a distinct posteromesal spine. Male genitalia: Ninth segment with anterior margin broadly produced laterally; posterior margin bearing a pointed process laterad of clasper base. Tenth tergum with ventrolateral margin lightly sclerotized, same length as claspers. Subgenital plate broadly rounded with a pair of submesal setae. Clasper enlarged apicad, dorsal margin with a large seta; apical margin rolled laterad, darkened, especially so at dorsal and ventral extremities. Phallus with basal section extremely long and slender; bearing a spiral process just basad of apical section which is long and slender, apex bearing a helical process spiralling around a central ejaculatory duct. Female genitalia: Eighth sternum bearing a mesal trilobate structure with posterolateral marks; posterior margin lightly sclerotized ventrally, apparently concave mesally, dorsal margin heavily sclerotized with a deep mesal emargination.

MATERIAL.—Holotype, male: COLOMBIA. DPTO. ANTIOQUIA: Quebrada Espadera, 7 km E Medcllín [road to Sta. Elena], 24 Feb 1983, O.S. Flint, Jr. USNM Type.

Paratypes: Quebrada La Ayurá, Envigado (trap B), Apr-Nov 1983, U. Matthias, 17, 19p. DPTO. RISARALDA: 4 km E Santa Rosa de Cabal, 29 Feb 1984, C.M. & O.S. Flint, Jr., 1.

This is another genus that is worldwide in distribution and well represented and varied in the Neotropical realm (Kelley, 1983). We have taken adult males and females of two species, but also possess females of two more species indicating that more species must be expected in the region.

The immature stages are well known. They construct silken cases with a narrow neck and broad, compressed, posterior portion. Full descriptions of the larvae are to be found in Nielsen (1948) or Wiggins (1977). They feed primarily on algae, but may consume other organic matter in the environment, and live in both lentic or lotie situations.