OBSERVATIONS ON THE BIOLOGY OF DASYPODA-H IRTIPES (F, 1793) (HYMENOPTERA, APOIDEA, MELITTIDAE)

The authors describe some aspects of the biology of Dasypoda hirtipes. The observations were carried out in 3 natural sites in Ile-de-France , of which one (a cemetery) has proven to be interesting because its p ermanence. The ground, predominantly sandy, permitted the digging of m any burrows, close to one another, constituting a ''bourgade''. The pr eparation of the nest, injury, was closely followed for about sixty fe males. The burrows are dug at 30 to 70 cm in depth, and include side g alleries that open on to the main gallery, with an oblique then vertic al course. Four to eight ovoid cells end, in line, each side gallery. The mating takes place on the ''bourgade'' site. Once the preparation of cells is completed, females prepare a pellet of pollen and honey, s pherical and resting on 3 feet, on which it lays an egg. The pollen pa ste is used as food for larva, during at least a week. At the end of t his period, larva enters a state of diapause, from the end of summer t o the beginning of the next. Pupation takes place the next year, witho ut formation of a cocoon. The pupal stage lasts about 5 to 6 weeks. Th e flying activity of Dasypoda depends, to a certain extent, on weather conditions. Normal in fine weather, this activity may be reduced unde r an overcast sky, and may even stop in rain or wind. Dasypoda depends on flowers for feeding, mainly Asteraceae. There is a synchronism bet ween the availability of the products (nectar, pollen) and visits to t he different floral species during the day. Analysing the pollen has e nabled us to draw up the list of visited flowers.