Figs 3 A, B
Material studied. Holotype male. FINLAND, Regio kuusamoensis, Taivalkoski, Kylmäoja (grid 7275293: 3554865), brook, Malaise trap, 11.vi– 3.vii. 2006, J. Salmela (in MZH). Paratypes. FINLAND, Regio kuusamoensis, Kuusamo, Uopajanpuro (grid 7362617: 3612763), brook, Malaise trap, 1–20.vi. 2005, J. Salmela (1 male in MZH); Lapponia kemensis orientalis, Salla, Värriö, Kuntasjoki (grid 7520406: 3610772), over brook, Malaise trap, 4–29.vi. 2013, J. Salmela (1 male in MZH).
Male. Head. Brown, antenna paler, maxillary palpus very pale brown. Eye bridge 2 facets wide. Face with 2–8 scattered longer and shorter setae. Clypeus with 1 setae or non-setose. Maxillary palpus with 2 or 3 segments; segment 1 longer than 2 and 3, these subequal in length; segment 1 with 2 long sharp setae, with a dorsal group of sensilla; segment 2 with 1 long sharp seta and 3–4 shorter truncate setae, segment 3 with 4–5 short truncate setae. Body of antennal flagellomere 4 2.7 x as long as wide, the neck shorter than broad, the longest setae shorter than the width of flagellomere. Thorax. Anterior pronotum with 1–4 setae. Episternum 1 with 4–5 setae. Wing. Length 1.9 mm. Width/length 0.45. R 1 /R 0.60–0.95. c/ w 0.80. r-m and bM non-setose. Halter pale brown. Legs. Front tibial organ with vestiture in indistinct patch. Front tibial spur slightly longer than the tibial width. Abdomen. Setae dark, rather short. Hypopygium (Fig. 3 A). Intercoxal area not lobe-like, medially much shorter than gonocoxite at the base of gonostylus, membraneous area richly setose; gonocoxa slightly longer than gonostylus, with normal setosity; gonostylus (Fig. 3 B) swollen, medially concave, with normal setosity, bearing an apical tooth, and 4–5 apical-subapical megasetae, megasetae slender, straight, subequal in length. Tegmen longer than broad, with a distinct apical process.
Female. Unknown.
Discussion. Claustropyga modica is one of the few species in the genus lacking any indication of the ventral intercoxal lobe of the hypopygium. The other similar species are C. aperta (Hippa et al. 2003), C. janetscheki (Mohrig & Röschmann, 1993), C. refrigerata (Lengersdorf, 1930) and C. sajanica (Mohrig & Antonova, 1978). Claustropyga modica is distinguished from C. janetscheki and C. aperta in having only 4 or 5 megasetae on its gonostylus, instead of nine or more, from C. refrigerata in lacking a group of lateral subapical megasetae on the gonostylus and from C. sajanica in the rounded, not angular, posterolateral shoulders of the tegmen and by having all the ventral gonostylar setae long and gently curved (in C. sajanica there is a posterior area of short and strongly curved setae). By its flattened apicoventral portion of the gonostylus, C. modica differs from all Claustropyga other than C. subcorticis (Mohrig & Krivosheina, 1985). The two species are otherwise greatly dissimilar.
Etymology. The name is Latin, modica (modest), referring to the unmodified structure of the hypopygium of the species.