Aquatic Coleoptera and Heteroptera inhabiting waterbodies from Berisso, Buenos Aires Province, Argentina.

Coleoptera and Heteroptera associated with aquatic environments were studied at Berisso, near Rio de La Plata estuary (Buenos Aires Province, Argentina). Four waterbodies were characterized and compared: artificial pond, shallow pool, stream and artificial channel. Sampling was done twice a month, with a round sieve, for 12 months (April 1999 to April 2000).

[Subfamily separation in the hemipteran family Gelastocoridae (Hemiptera)].

Gelastocoridae (Kirkaldy, 1897) has over 70 species in two subfamilies: Nerthrinae (Kirkaldy, 1898), genus Nerthra (Say, 1832) and Gelastocorinae (Champion, 1901), genus Gelastocoris (Kirkaldy, 1897). The position of the cephalic gland openings, presence and shape of the gular bridge and the number and position of abdominal spiracles, are presented as new morphologic diagnostic characteristics that support the argument used by Todd for the segregation of the subfamilies. The characteristics are described and illustrated on the basis of specimens from Laguna Iberá, Corrientes, Argentina.