k-i Journal of Insect Conservation 4: 215-223, 2000. W © 2001 Khmer Academic Publishers. Printed in the Netherland .
Status and breeding sites of three resumed endangered Scottish sapro ylic syrphids (Diptera, Syrphidae) G.E. Rotheray1'* & I. MacGowan2 , , ,F T, K
1 National Museums of Scotland, Chambers Street, Edinl gh EHl 1JF, . .
cottish Natural Heritage, Battleby, Redgorton Perth fa'013J 2204819 phone: 01312474243) Authorfor corre pondence (e-mail:
[email protected], fax. 01312204819, pno Received 24 March 2000; accepted 27 July 2000
Key words: conservation, red-listed, flight period, distribution
Abstract From 1 87 tol99 efforts were made to un erstand the status
schnmmef (Diptera,
in Britain: Blerafallax (Linnaeus), Hammersc mi d s e, were collated fro the literature and Syrphi ae). Historical data on flight periods, kmahtres and es ™ caphrred specimens in museums and other dranlooldng
a
rrm
destruction affect most of its sites.
was Coe (1938), who described the larva of C. rufa from Introduction Three red-listed saproxylic Syrphidae (Diptera) are confined to Scotland within the British Isles: Blera fallax (Linnaeus), Hammerschmidtiaferruginea (Fallen) and Callicera rufa Schummel (Stubbs & Falk 1983). They are accorded the highest category of threat (category 1, endangered) in the Red Data Book (Insects) (Shirt 1987). Practically no attempts have been made to conserve individual species of Diptera in Europe. However, endangered saproxylic Diptera
might be considered prime candidates for individual conservation effort, particularly given concern over the
plight of saproxylics and their habitats (Speight 1989). Their conservation would also help to maintain thenoodland habitats and associated species. However, the conservation needs of these three species were poorly known until recently. They were
rarely recorded, little biological information was available and the status of existing populations was uncertain. The only rearing record in Shirt (1987)
specimens found in a tree-hole in Pinus sylvestns L. In Russia, the larva of H. ferruginea was found and described from under bark of Populus tremula L.
(Krivosheina & Mamaev 1967), although these data are missing from Shirt (1987). The larva of B. fal¬ lax was unknown in 1987, but recently pupana were found in holes at the cut surfaces of P. sylvestns tree
stumps (Rotheray & Stake 1998) and more recently, larvae have been found.
In this paper we review the status and knowledge of breeding sites of these three species based on an analysis of data obtained from captured specimens in museums and other collections, published sources and
fieldwork in Scotland during the period 1987-1999.
Materials and methods Specimens in museum collections were examined and the following data extracted: species, stage, sex,
216 G.E. Rotheray & I. MacGowan lable 1. Identification of larvae Recognition features B!era fallax: a long-tailed larva
(>half rest of body length) bearing two pairs of fleshy pro¬ jections at the base of the tail, thorax broad without groups of 2-3 hooks, mouth-hooks
Mdpuparia of Blera fallax, Hammerschmidtia ferruginea and Callicera rufa. Comparison with morphologically similar species occurring in Scotland M. florea: also long-tailed but does not have pairs of fleshy ro¬ jections at the base; also ith longer than broad anterior spira¬ cles, anterior spiracles retractile
into pockets on the integument
not protruding from the mouth, anterior spiracles as long as broad, prolegs ith crochets present Hammerschmidtia f r giiiae anal segment without a tail, dorso-ventrally flattened with gradually elongatingprojections along the lateral mar ins; poste¬ rior respiratory process shorter
than maxi um body width; dorsal surface of abdomen evenly coated in setae, prolegs
Brachyopa spp.: anal segment
without a tail, posterior respi¬ ratory process about as long as
maximum body width, dorsal surface of abdomen with four
Xylota sylvamm: tail not as long
(
