Key to the infraorders of Heteroptera in South America

Information for the key was provided by Schuh and Slater (1995) and Schaefer (2003).

1. The head has a transverse constriction, dividing it distinctly into two lobes. Compound eyes are usually present, but they are absent or reduced in a few species. If ocelli are present, they are located on a lobe posterior to the compound eyes. The fore-tibiae are flattened and have distinct distal spines. The fore-tarsus has one or two segments, which form an opposing organ for grasping with the anterior part of the fore-tibia. If fore-wings are present, the texture of their surfaces is uniform. A claval commissure is absent, so a distinct corium and membrane are not evident (Fig. 6.3). Enicocephalomorpha

Two families in this infraorder are known: Aenictopecheidae and Enicocephalidae. The species are terrestrial predators and are not further considered in this volume.

- Either the head is not constricted and lacks distinct lobes, or there is a distinct sulcus in the presternum to receive the apex of the labium, and the fore-tibia is not flattened or lacks distinct distal spines, which oppose the one or two-segmented tarsus (Fig. 6.4). Compound eyes are present, except in species parasitizing bats or inhabiting termite nests 2

Fig. 6.3 Enicocephalus schuhi Wygodzinsky and Schmidt, 1991: habitus without wings in dorsal view (middle left), antenna (upper left), head in lateral view (lower left), head with one antenna and thorax in ventral view (lower center), fore-wing (upper right), apex of hind wing (lower right), apex of the fore-leg (right of center) and details of the apex in ventral view (lower right center). This terrestrial species, found in Rio de Janeiro, belongs to the Enicocephalidae. Based on Wygodzinsky and Schmidt (1991).

Fig. 6.3 Enicocephalus schuhi Wygodzinsky and Schmidt, 1991: habitus without wings in dorsal view (middle left), antenna (upper left), head in lateral view (lower left), head with one antenna and thorax in ventral view (lower center), fore-wing (upper right), apex of hind wing (lower right), apex of the fore-leg (right of center) and details of the apex in ventral view (lower right center). This terrestrial species, found in Rio de Janeiro, belongs to the Enicocephalidae. Based on Wygodzinsky and Schmidt (1991).

Fig. 6.4 Habitus of a brachypterous Eurygerris fuscinervis in dorsal view (upper left), body of a macropterous individual (lower left), and the head and thorax in lateral view (right). Based on Alvarez and Roldan (1983), who used its synonym, E. kahli.

2. (1) Three or four pairs of distinct trichobothria inserted in deep pits are present on the head near the inner margins of the compound eyes, which are always present. There is a coating of hair-like setae around the margin of each pit, which is deep enough to conceal the bothrium. If fore-wings are present, they lack a claval commissure, and a border separating the corium and clavus from the membrane is not evident (Fig. 6.4). A large part of the body is densely coated by tiny setae and many longer setae to repel water and maintain a coating of air on the surface of the body if the insect is forced below the surface of the water. The hind coxae are short and free-moving to permit rotary motion. They are typically found on the surface tension layer and occasionally along the shore of both freshwater and marine habitats.

Gerromorpha..p. 68

- Either the head lacks trichobothria, or, if present, they are not set in pits (Fig.

Fig. 6.5 Ctenipocoris schadei (above, left to right): habitus of an adult and a fifth and a third instar larva, and (below, left to right): antenna, male genitalia, penis in ventral (above) and lateral view (below), paramere, and female genital capsule. Based on Lopez Ruf (2004).

3. (2) The antennae are not as long as the head and are usually folded beneath it, in well-defined pits in all families except the Ochteridae. Compound eyes are always present and usually large; only the apices of the antennae are sometimes visible beyond the margins of these eyes. The poststernal sulcus is always absent. Most adults are macropterous, but a few have shortened hemielytra, resembling the wing covers of staphylinid beetles. Macropterous forms always have claval commissures (Fig. 6.5). The insects are typically found underwater, although flights may be undertaken during certain seasons.

0 0

Post a comment