BIOLOGY OF NEOHYPNUS-PUSILLUS (SACHSE) (COLEOPTERA, STAPHYLINIDAE) AND ITS PREDATION ON IMMATURE HORN FLIES IN THE LABORATORY

The arthropod community of cattle dung pads in a pasture in Alachua Co unty, Florida, included three species of Neohypnus Coiffait and Saiz, of which Neohypnus pusillus (Sachse) was the most abundant. Adult N. p usillus were collected year round and were most abundant during June, July and August. The developmental time of immature stages from ovipos ition to adult emergence was 26-36 d (avg. 29.5) at 27 degrees C. It t ook 5-8, 13-20 and 6-8 d for the egg, larva, and pupa to develop, resp ectively. Both adults and larvae preyed on eggs and larvae of the horn fly [Haematobia irritans (L.)], when confined together with no other food available. Each adult consumed 4.2 eggs and 5.9 larvae of horn fl ies per day. Similarly, each larva consumed 9.0 horn fly eggs and 83.5 larvae during its active stage. The egg, larva and pupa of N. pusillu s are described.