Beitrag zur Larvalmorphologie der Palpenkaefer (Coleoptera, Pselaphidae)

1997

S. 57-68

9 Lit. Ang.

Unselbständiges Werk

200079217

A description of the presumable mature larva (erd instar) of Bryaxis puncticollis (DENN.) is given and compared with Tychobythinus and with Bryaxis italicus (BAUDI), the only species of Bryaxis known in the larval stage so far, both described by DE MARZO (1987). Tychobythinus and Bryaxis differ in the shape of the 8th abdominal tergite and probably in the broader base of the bifurcate sensillum basiconicum on the 2nd antennal article in Tychobythinus. Both species of Bryaxis are characterized by a different shape of the maxilla and show further slight chaetotaxical differences, especially on the clypeus. For Plectophloeus fischeri (AUBE) a more detailed figure of the head and some other figures are given. Additional to BESUCHET (1952) the exsertile head organs are shown. The two last instars can be distinguished by comparing the shape of the 9th abdominal segment. The presumed larva of Reichenbachia juncorum Leach is described and figured. it differs from Brachygluta (DE MARZO 1987) by long and sharp pointed urogomphi. Hitherto the fusion of labrum and frontoclypeus was regarded as one of the general characters of larval pselaphids. At least Plectophloeus, Reichenbachia and Pselaphus possess a distinct labrum, which is clearly separated from the frontoclypeus by a narrow membraneous belt and is only visible from frontal, in Pselaphus from ventral view of the head. The examined specimens were obtained by extraction of soil samples in a Tullgren apparatus.