Bradysia tilicola ( Loew, 1850 )

Broadley, Adam, Kauschke, Ellen & Mohrig, Werner, 2018, Black fungus gnats (Diptera: Sciaridae) found in association with cultivated plants and mushrooms in Australia, with notes on cosmopolitan pest species and biosecurity interceptions, Zootaxa 4415 (2), pp. 201-242 : 224

Bradysia tilicola ( Loew, 1850)

( Fig. 10 A–E )

Sciara tilicola Loew, 1850 [ Loew (1850): 18].

Common synonyms: Bradysia amoena (winnertz, 1867); Bradysia caldaria (Lintner, 1895) ; Bradysia coprophila (Lintner, 1895) .

Literature: winnertz (1867): 114–115 (as Sciara amoena ); Lintner (1895a): 394–396, figs 4, 5 a–e, plate I, figs 1–4, 8, 9, 11, 11 a (as Sciara coprophila ); Lintner (1895b): 397–399 (as Sciara caldaria ); Johannsen (1912): 120, 123, 136–137, plate III, figs 133, 144; Smith-Stocking (1936): 421-443, figs 1–3 (both as Sciara coprophila ); Lengersdorf (1925): 211, plate VII, fig. 29 (as Sciara amoena ); Tuomikoski (1960): 129–132; Freeman (1987): 202, fig. 10; Blaschke-Berthold (1988): 347–350, figs 3, 8, 11; Menzel & Mohrig (2000): 147–151, figs 132–133 (all as Bradysia amoena ); Menzel et al. (2006): 63–64; Menzel et al. (2013): 286–287; Mohrig et al. (2013): 171–172.

Material studied. 3 males, 1980, Melbourne, ex lab. colony, ASCT 00053385 ( PABM)/53386/53387 ( ASCU), leg. A.J. Stocker. The determination is not certain, since males were embedded in an artificial resin which deformed the specimens by shrinking. The wings show a slight aberrant venation in all three specimens which might be caused by artificial rearing in the laboratory culture. The typical macrotrichia on y are present in the specimens. The specimens that we examined were part of a lab colony originally sourced from a laboratory in the USA (A. Stocker, personal communication). We have not seen any collected from the ‘wild’ yet. Until we do we must regard B. tilicola as not recorded in Australia.

B. tilicola is widespread in the Holarctic region . It is common in flower pots, in glasshouses, and has been reared from fungi, tulip and lily bulbs, decaying onions, and young ling seedlings. In open landscapes, it has been found in gardens, farmland, alder carr woodland, moorland, and wetlands including fens, bogs, and sedge beds (Menzel et al. 2006). In the southern hemisphere it has been reported from Tristan da Cunha archipelago, where it was introduced by humans.

Diagnostic remarks. The species can easily be identified as belonging to the genus Bradysia by the comb-like row of bristles at the apex of the fore tibia, a rather long R1 and more than 2 bristles on the basal palp segment. It is characterized by the 4th flagellomere with l/w index of 2.5, a deep sensory pit on the basal segment of the palpus, macrotrichia on the x and y wing veins, hypopygium without a basal lobe, gonostylus with a short tooth located dorsally and a dense group of longer apical/subapical spines and a trapezoid tegmen. The macrotrichia on x and y are especially good diagnostic characters.

Economic importance. The species is common in houses with plant pots but rare in greenhouses and mushroom cultures. It is usually a harmless cohabitant and does not cause economic damage to plants.

Distribution. Holarctic. For the southern hemisphere there is only one verified report, from the Tristan da Cunha archipelago (Menzel et al., 2013) [the report from New Zealand ( Sciara marcilla Hutton, 1902 ) is not certain (Mohrig & Jaschhof 1999: 96)].

Figures

FIGURE 10. Bradysia tilicola (Loew, 1850); (specimen from Europe). A. Hypopygium. B. Flagellomeres 4–5. C. Palpus. D. Fore tibia.E. wing.