My duck has focused a wee too much on dolichopodids of late, and even though these dainty hunters present a bounty of discoveries, the order Diptera offers at least 130 other families of interest to fans of flies. The Belgian entomologist Patrick Grootaert has been busy surveying habitats in Singapore and Southeast Asia in recent years, seeking tiny flies that mostly thrive only in moist, muddy and mangrove-infested swamps. Little is known about them other than their existence and until Grootaert came along, many lacked names. Often, their presence is indicative of habitats that are pristine and consequently most at risk of degradation from human activities. Grootaert's specific interest lies in the flies of the suborder Empidoidea, in which Dolichopodidae is placed. His sojourns to Singapore have resulted in numerous papers covering the family and its genera, including Teuchophorus (13 local species, including 9 new ones, described), the erection of the cynical genus Ngirhapium and 4 new species of Paramedetera.
Grootaert has also a strong interest in dance flies (Empididae), a predatory family in the suborder known for the furious swarms that make up their mating dance. Males capture small prey (midges and other minute flying insects – see the photo of a British species below right) and offer these to the females in courtship. But some species are known to spin an empty ball of silk which is offered to the lady who gets bonked before she has fully inspected the prize to find an empty package, a practice with lessons for larger apes. Like dolichopodids, larval empidids live in moist or aquatic habitats, and the adult dance flies can be distinguished from their long-legged cousins by a generally more robust build and the lack of a metallic sheen.
The latest focus of Grootaert's scholarship is not empidids, however, but Hybotidae, a family of flies once regarded as a subfamily of Empididae but are now on par on account of arcane features such as "the presence of a palpifer, fore tibial gland, gonocoxal apodeme restricted to anterolateral margin of hypandrium (lacking process), apex of antennae often with long slender seta-like receptor, laterotergite bare and R (4+5) unbranched." Earlier, the largely Thai genus Stilpon was reviewed, but in a recent issue of Zootaxa, Grootaert and longtime collaborator Igor V. Shamshev turned their attention to the hybotid flies of Singapore and the Orient, describing 59 new species in the genus Elaphropeza, a monstrous tally to the previous count of 79 known Oriental species. Fourteen of these new species are found only in mangroves and the bulk of samples were collected right here in Singapore over a year. Grootaert notes that despite the extensive sampling, a third of local species are known only from singletons and doubletons, suggesting that "a large number of species still remain undiscovered." Among the newly described flies, E. combinata is found only in Nee Soon swamp, while E. sime is known only from the eponymous forest that is its type locality.
Small and predacious, Elaphropeza flies are predominantly yellowish and found in forested areas, although a number of species are black-bodied and favour sunny, exposed location. They appear very habitat specific. Virtually zilch is known about their behavioural ecology and Grootaert seems almost frustrated when he describes the enigmatic abdominal modification of one new species which resembles a primitive stridulatory device. In the absence of direct observations, he suggests could be used to produce vibrations on a substrate. Elaphropeza are usually found on leaves and the larva are believed to be hyperparasites on other flies.
The obvious message for conservation from Grootaert's paper is that a vast mountain of unknowns lies within the borders of this tiny island, which prides itself in biotechnology leadership but seems loathe to protect the unique and irreplaceable genotypic wealth that yet dwell in its diminished ecosystems. This cohort of newly discovered flies may well gain a dubious immortality that outlives their type (and possibly sole) localities, which now shelter E. neesoonensis, E. chekjawa, E. bulohensis and E. ubinensis. Less clear a lesson is that outstanding endeavour in obscure arenas may one day earn the homage of specific honorifics. But I suspect even the likes of Benito Tan and Wang Luan Keng will probably be at a loss when trying to describe the distinguishing features of the minute beasts christened E. luanae and E. benitotani. Grootaert further dishes out a who's who of Singapore biodiversity in creatures such as E. darrenyeoi, E. yeoi (after K.L. Yeo), E. murphyi, E. meieri and E. ngi. The etymological section of E. sivasothii is dedicated to a certain "Dr. Sivasothi, one of the 'lords' of the mangrove, which means that he has a high interest in the study of mangroves and their protection". Another mangrove obligate, E. riatanae, is dedicated to a fabulous lady "for the great work she is doing in Singapore in popularising the marine life through excellent photography published in books, leaflets and on websites." Grootaert gives credit to Ria's published work on Chek Jawa for contributing to the site's protection (for now), but dare we hope that this and other shores will remain in perpetuity, unravaged by the boundless urge of men to lord over land and sea, even if these conquests result in littorals of lifeless desolation?
nice blog,was an interesting read
keep it up mate :)
Posted by: aphid | 16 June 2007 at 09:18 PM