Trichosiopsis defecta
Ordo: Diptera
Familia: Sciaridae
Genus: Trichosiopsis
Name
Trichosiopsis defecta (Strobl, 1910) – Wikispecies link – ZooBank link
- Sciara elegans var. defecta Strobl, 1910[1]: 233
- Leptosciarella (Leptosciarella) defecta (Strobl, 1910)[2]
Type material
Holotype: ♂, leg. Strobl, in NMBA
Type locality
Austria, Styria, Kematenwald
Further material studied
Switzerland: 1 ♂, Zurich, Sihlwald, photoeclector, Schiegg, 25.4.-23.05.1996, PKHH 2478; 1 ♂, window trap, Schiegg, 24.5.-05.06.1996, PKHH 1812.
Description (male)
Head. Eye bridge 4–5 rows of facets. Antennae unicolour. LW-index of 4th antennal flagellar segment 2.5–3; neck 0.38–0.43 × segment width; Transition of basal part to neck pronounced. Colour of neck unicolour. Antennal hairs shorter than segment width; fine; dense; adjacent. Palpi darkened; palps normal; palpomeres 3. First palpomere elongate; with 3–5 bristles; with only some sparse sensillae. Second palpomere elongate. Third palpomere as long as first segment. Thorax. Colour brown, or reddish. Notum partially brightened. Thoracic setae long and strong; black. Mesonotum with some weaker central bristles. Posterior pronotum setose. Postpronotal setae 1–4; fine. Mesothoracic sclerites bare. Legs. Colour yellow. Hind coxae of same colour as femora. Hairs on fore coxae black. Front tibia apically with a patch of setae. Front tibial organ dark. Front tibial organ not bordered. Tibial setae on hind legs very strong, as long or longer longer than tibial width. Tibial spurs of equal length. Claws untoothed. Wings. Wings slightly darkened; of normal shape. Wing membrane without macrotrichia. Wing venation weak, with faint m-base. M-fork of normal shape. R1 inserting clearly after base of m-fork; posterior veins with macrotrichia; stM mainly with macrotrichia; cuA1 and cuA2 mainly with macrotrichia; bM bare; r-m mostly setose; bM:r-M 0.75–0.85; st-Cu:bM 0.4–0.65; r1:r 1.75–2; C:w 0.54–0.65. Halteres dark; of normal length. Abdomen. Abdominal setae strong and dense; dorsally black; ventrally black. Hypopygium concolour with abdomen; 0.65–0.75 × longer than wide. Base of gonocoxites with strong setae; gonocoxites broadly separated; inner margin of gonocoxites normally U-shaped; inner membrane of hypopygium densely setose; elongated setae on valves of hypopygium absent. Gonostylus elongate; 1.95–2.25 × longer than wide; Inner margin concave; apex with one obtuse angle. Apical tooth present; 2.1–2.6 × longer than broad; strong, or normal. Apical tooth without internal structure. Awl-like setae normal; on inner side of gonostyles apically present. Megasetae on inner part of gonostylus absent. Whiplash-hair absent. Tegmen 0.6–0.8 × longer than broad; rectangular with rounded edges; normal; Central process absent. Length of ejaculatory apodeme/hypopygium 23–30 %; Aeadeagal apical structure present. Field with aedeagal teeth present. Measurements. Body size 2.3–3.5 mm. Hind tibia 1.25–1.75 mm. Wing length 2.5–3.5 mm.
Diagnosis
Trichosiopsis defecta is rich in contrast by the shiningly yellow legs and the dark body with dark, long setae, especially on the fore coxae. The thorax is partly reddish laterally, which makes the species still look more colourful. A similarly contrasting species is Leptosciarella ignis, which can be distinguished by more slender gonostyli, weaker setae at the base of the gonocoxae and bright hairs at the fore coxae. The setae on the hind tibia are very conspicuous in Tr. defecta and nearly as long as the tibial width. The apically tapered and angulate gonostyles and the long setae at the base of the gonocoxites are typical for species of the Le. rejecta group like Leptosciarella rejecta. The ventral border of the gonocoxites is conspicuously darkened and there are numerous strong bristles also on the inner membrane.
Discussion
Le. defecta was originally described by Strobl only as a smaller variant of Sciara elegans [= Trichosiopsis scutellata]. The coloration of both species is similar, but the male genitalia are clearly different. Menzel (1992[3]: 243) had studied the holotype and identified it with Leptosciarella scutellata sensu Frey [= Trichosiopsis pilosa (Staeger, 1840) – Mohrig & Menzel (1997)[4]: 72)], from which is is distinguished by the male genitalia, especially by the long setae at the base of the hypopygium. The previous species concept behind the name Leptosciarella defecta on Species-ID[2] and subsequently in the literature[5] has proven to be still too broad, as it contained a mixture of several different species. The holotype is significantly smaller than the other available material of Tr. defecta, but for the moment it is considered to be the same species, because all other characters are identical.
Etymology
defectus lat. = weak. Referring to the small size of the species.
Ecology
Trichosiopsis defecta is to date only known from Austria and Switzerland and is possibly a strictly alpine species.
Distribution
Austria[1], Switzerland.
Images
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References
- ↑ 1.0 1.1 Strobl, G. 1910: Die Dipteren von Steiermark. II. Nachtrag. Mitteilungen des Naturwissenschaftlichen Vereines für Steiermark, 46(1909), 45–293. BHL
- ↑ 2.0 2.1 Heller, K. 2014: Leptosciarella defecta Species-ID [1]
- ↑ Menzel, F. 1992: Beiträge zur Taxonomie und Faunistik der paläarktischen Trauermücken (Diptera, Sciaridae). Teil I. - Die Stroblschen Sciaridentypen des Naturhistorischen Museums des Benediktinerstifts Admont. Beiträge zur Entomologie, 42(2).
- ↑ Mohrig, W.; Menzel, F. 1997: Revision der paläarktischen Arten von Trichosia Winnertz sensu Tuomikoski, 1960 (Diptera, Sciaridae). – Teil II. Gattungen Leptosciarella Tuomikoski, 1960 und Trichodapus gen. nov. Studia dipterologica, 4(1), 41–98.
- ↑ Heller, K.; Weber, D. 2013: Trauermücken (Diptera, Sciaridae) aus Höhlen des Großherzogtums Luxemburg. Ferrantia, 39, 320–336.
