Boletina curta Sasakawa & Kimura, 1974

Salmela, Jukka & Kolcsar, Levente-Peter, 2017, New and poorly known Palaearctic fungus gnats (Diptera, Sciaroidea), Biodiversity Data Journal 5, pp. 11760-11760 : 11760

Boletina curta Sasakawa & Kimura, 1974

Boletina curta Sasakawa & Kimura, 1974: 60 (fig. 15a,b,c)

Boletina curta Zaitzev 1994: 209 (fig. 69,7)

Materials

Type status: Paratype. Occurrence: recordedBy: M. Sasakawa; individualCount: 1; sex: male; Location: country: Japan; stateProvince: Honsu; verbatimLocality: Otsu, Mt. Hiei; verbatimLatitude: 35.06; verbatimLongitude: 135.83; verbatimCoordinateSystem: decimal degrees; verbatimSRS: WGS84; Identification: identifiedBy: J. Salmela; Event: eventDate: 1974-5-3; Record Level: institutionCode: OSAKA

Distribution

Boletina curta is a poorly known East Palaearctic species, hitherto recorded from Japan, Honshu ( Sasakawa and Kimura 1974) and Russia, Sakhalin ( Zaitzev 1994). Boletina curta is probably on the wing early in the season: collecting dates of the holotype and all paratypes (except Yoshino, the holotype of. B. sasakawai sp.n., see below) range between April 27 and May 3. However, Russian specimens reported by Zaitzev (1994) were collected in autumn (September 21).

Taxon discussion

Boletina curta was described from Honshu, the main island of Japan ( Sasakawa and Kimura 1974). The type material consists of the holotype male, collected from Mt. Hiei, and paratypes collected from four other localities (in addition, an allotype female from a further site). Two of these paratypes were studied by the authors, and the paratype from the type locality was found to be conspecific with B. curta . This paratype, despite its explicit labeling, was not mentioned in the original description ( Sasakawa and Kimura 1974). The second paratype, collected from Yoshino, does not fit to the concept of B. curta , and is here described as a new species (see below B. sasakawai sp.n.).

Boletina curta can be separated from the closely related B. sasakawai sp.n. and B. norokorpii sp.n. based on the following characters: 1) two stout setae present on the ventral lobe of the gonostylus (in the other taxa the ventral lobes of the gonostyli are bare, Fig. 7c), 2) the mid and hind femora are ventrobasally yellowish (infuscated in B. sasakawai sp.n.) and 3) the proximal row of stout setae on cerci (comb-like rows) is wider than apical row (Fig. 7b) (in the other taxa the rows are approximately equally wide, see Figs 8b, 9b). Furthermore, tibial spurs of B. curta are very dark (yellowish in other species) and the first flagellomere of B. curta is yellowish (becoming apically infuscated in B. sasakawai sp.n.); pedicel:first flagellomere length ratio of B. curta is 0.32 (0.24 in B. sasakawai sp.n. and 0.36 in B. norokorpii sp.n.). For the details of the male hypopygium of B. curta , please see Fig. 7.

Some Boletina species, such as B. trivittata Staeger, occur in both early and late season (J. Salmela, pers.obs.). Hence, it might be possible in theory that B. sasakawai sp.n. is just a late summer/autumn morph of B. curta , likewise the butterfly species Araschnia levana (Linnaeus), that has two distinct colour morphs within a season (see e.g. Ihalainen and Lindstedt 2012). Boletina trivittata , however, has overwintering adults, and so it is not truly bivoltine such as A. levana , that produces two adult generations within a summer. We assume that B. sasakawai sp.n. is not a late season morph of B. curta , because we found notable differences in the structure on male genitalia.