D. obscura Fallén 1823 
(previously called D. obscuroides Pomini 1940)

Last update: 17 August, 2002

Picture of Drosophila obscura
(female with male abdomen) by
Hilary Burn

An extremely abundant and widespread species usually surpassed in numbers only by D. subobscura in most areas. It has been trapped in almost all types of outdoor habitat except for moorland and open coast. However, it is most abundant in woodland: in the survey conducted by Dyson-Hudson (1954), 72% of all D. obscura taken were from woodland habitats, 14% were from habitats associated with man, and a further 14% were from open habitats. There is some evidence that D. obscura reaches its highest frequencies in urban areas. Adult flies have been recorded from sap of elm, oak, lime, birch, alder, beech, willow, and sycamore. Gordon (1942) noted that a number of Drosophila eggs and larvae were found in the yeasty exudate uncovered when bark was removed from an elm tree. These were transferred to standard culture medium and from the 150 larvae collected, 20 male and 29 female D. obscura (but no other species) emerged. From December to March few flies are obtained. In April, however, numbers begin to build up and reach a peak from June to August, declining thereafter.

Prof. B. Shorrocks

Bibliography
Dyson-Hudson, V.R.D. 1954 The taxonomy and ecology of the British species of Drosophila. D.Phil. thesis (deposited in the Bodleian Library, Oxford, and in the library of the Department of Zoology and Comparative Anatomy, Oxford University).  Back

Gordon, C. 1942 Natural breeding sites of Drosophila obscura. Nature, London 149, 499.  Back