Lonchaea zetterstedti
Female. Size medium; slightly smaller than L. chorea (Fab.). Mostly shining blue black, with short antennae, white fringed calypterae and yellow metatarsi.
Frons slightly narrower at lunule than at vertex; sub shining black in most views; without distinctive grooves or depressions. Orbital plate with one to several setulae arising above the orbital bristle. Cheeks and parafacials relatively narrow; oral setulae in a single row. Antennae moderately short, reaching to oral margin only; second segment and inner base of third brownish orange; third segment slightly longer than broad (3.5:3.0), mostly dull blackish. Arista microscopically pubescent. Compound eyes bare.
Mesonotum almost entirely glossy black; pollen restricted to prescutellar area between base of scutellum and the posterior dorsocentral and acrostical bristles. Mesopleuron and sternopleuron glossy black. Notopleuron and pteropleuron lightly pollinose. With single propleural and stigmatal (= proepimeral) bristles. Mesopleuron with three posterior bristles. Sternopleuron usually bare behind sterno pleural bristle, but sometimes with a small setulae in this position.
Scutellum pollinose dorsally; with two or three lateral setulae between the scutellar bristles; apex without apical setulae (occasionally with an adventitious hair in this position). Two basal segments of all tarsi yellow; three apical segments increasingly darker brown towards apex. Wings yellowish hyaline with yellow veins. Distance between apices of Sc and Rl moderately short, i.e., slightly longer than greatest width of subcostal cell (1.75:1.5). calypterae white with concolorous margins and fringes.
Abdominal tergites mostly glossy black, lightly dusted with greyish pollen on disc of terga 1 3 inclusive; sterna mostly polished brownish black the pollen restricted to basal and lateral margins. Ovipositor (see Hackman. 1956, p. 104, fig 73 Morge 1963, p. 298, fig. 173) long and slender. Apical segment rather short and drooping; with a pair of very long, whitish, dorsal hairs arising near base, with another pair of subapical, ventral hairs about half as long as the long dorsal hairs and also with a much shorter pair of subapical dorsal hairs.
Male. Agreeing with female in general appearance and structure, except for usual sexual differences. Somewhat smaller in size, and with longer, more erect, hairs and setae. Frons unusually narrow, at narrowest point about one seventh as wide as head. Genitalia as in Figs. 2, 3, 4. Epandrium with a distinct emargination on posteroventral margin. Surstylus little exposed in side view × ventral margins strongly toothed. Anterior gonapophysis unusually lar~e and strongly sclerotized; apex overlapping basal third of apical segment of aedeagus.
Aedeagal guide not prominent in lateral view. Apical segment of aedeagus slender and with a lobe like expansion at base.
L. zetterstedti is a typical member of the Lonchaea corticis group of species which share bare eyes, rather short antennal flagellomere, narrow parafacials, a single row of anterior genal setulae, several setulae on the orbital plate above the orbital setae, one stigmatical setae, calyptrae with a pale fringe of uniform length, apical segment of aedeagus S-shaped and apical segment of the aculeus with long to very long sub-basal setae. There are currently 6 other members of this group; L. corticis Taylor (Nearctic), L. coloradensis Malloch (Nearctic), L. defecta McAlpine (Holarctic), L. ipsiphaga McAlpine (Palearctic), L. maniola (Nearctic) McAlpine (Nearctic) and L. seitneri Hendel (Palearctic). The larvae of all of these species are associated with conifers. (McAlpine and Morge, 1970)
In Europe L. zetterstedti is most closely related to L. seitneri, but the presence, in both sexes , of 3-6 setulae between the apical scutellar setae in L. seitneri serves to distinguish it from L. zetterstedti. Nearctic specimens of L. zetterstedti are most likely to be confused with L. maniola and L. defecta but the absence of setulae between the apical scutellar setae and the presence of extremely long setulae on the apical segment of the aculeus serve to distinguish L. zetterstedti. A key to this group is given in (McAlpine and Morge,1970)
This species occurs in the boreal forests of both Europe and North America where the larvae live under the bark of recently fallen coniferous trees. In the British Isles this species has been reared from larvae found under the bark of fallen trees, logs and stumps of cut conifers belonging to the genera Larix, Picea and Pinus.
coniferous woodlamd