Trichosiopsis

From Species-ID
Revision as of 15:12, 14 October 2012 by Kai Heller (Talk | contribs) (Etymology)

Jump to: navigation, search

Taxonavigation

Ordo: Diptera
Familia: Sciaridae

Name

Leptosciarella Tuomikoski, 1960 validWikispecies link

  • Trichosia (Leptosciarella) Tuomikoski, 1960: 20[1]

Type species

Description (male)

Head. Eye bridge 3–5 rows of facets. LW-index of 4th antennal flagellar segment 1.5–4.0; Transition of basal part to neck pronounced, rarely bottle-neck shaped. Palpomeres 3., rarely 2. First palpomere with numerous bristles; with only some sparse sensillae. Thorax. Thoracic setae strong or normal. Posterior pronotum normally setose. Laterotergite normally bare, rarely with bristles. Legs. Frontal tibia with a patch of setae. Front tibial organ mostly dark. Front tibial organ not bordered. Tibial spurs elongate, of equal length. Claws untoothed. Wings. Wings darkened, of normal shape. Wing membrane with or without macrotrichia. Wing venation normal. M-fork of normal shape. R1 inserting at or slightly before base of m-fork; posterior veins mostly with macrotrichia. Halteres of normal length. Abdomen. Abdominal setae normally strong and dense. Hypopygium concolour with abdomen. Inner margin of gonocoxites normally U-shaped; inner part of hypopygium densely setose; elongated setae on valves of hypopygium absent. Gonostylus elongate; inner margin straight, or concave. Apical tooth present. Apical awl-like setae present. Megasetae on inner part of gonostylus absent. Tegmen mostly rectangular with rounded edges; central process absent. Measurements. Body size 2.0–4.5 mm. Wing length 2–4.5 mm.

Diagnosis

Leptosciarella belongs to the basal clade of Sciaridae together with Sciara and Trichosia. These genera are characterized by setose wing veins and a patch of numerous setae on the inner side of the apex of the fore tibia (tibial organ). Characteristic for the genus are the awl-like setae at the apical part of the gonostyles, which are deemed to be secondarily reduced in the subgenus Protosciarella. Awl-like setae occur otherwise only in the genus Sciara. Leptosciarella can be distinguished from Sciara by the presence of an apical tooth (Menzel & Mohrig 2000: 355)[2], which is supposed to be reduced in the subgenus Trichosiopsis. The species are normally dark, slender, strongly setose and have long legs.

Etymology

gr. leptos, λεπτός = tiny, fine, small. Sciarella = diminutive of the genus name Sciara. The combination refers to the genus name Leptosciara Frey, which is a synoynm of Trichosia.

Ecology

Species of this genus are mainly found in forests. Many species live upon dead wood and the adults occur mostly in spring.

Discussion

Leptosciarella was originally defined by Tuomikoski as a subgenus of Trichosia. Amorim (1992: 62)[3] was the first, who treated Leptosciarella as a genus, but without any discussion. Due to the lack of autapomorphic characters of Trichosia s.l. (Mohrig & Menzel 1997)[4] confirmed this usage and defined the genus on the presence of a beak-like apical tooth and awl-shaped setae at the tip of the male gonostyles. Although these characters can be variable among species, the genus is quite clear-cut and there are currently few doubts about its delimitations. There are five accepted subgenera (Hirtipennia, Leptosciarella, Leptospina, Trichosiopsis and Proto­sciarella). In the latest revision of the genus (Mohrig & Menzel 1997)[4] 36 species were included, with Lepto­sciarella s. str. being by far the largest subgenus with 27 species. 55 species are currently assigned to this genus, but a large number of undescribed or unrevised species are also belonging here.

Distribution

The distribution of Leptosciarella is mainly palaearctic except for the Neotropical subgenus Proto­sciarella (Mohrig 2003)[5] (4 species) and another four recently described oriental species from Taiwan (Rudzinski 2005)[6].

Currently available species revisions on Species-ID

Leptosciarella gretae, Leptosciarella helvetica, Leptosciarella hispida, Leptosciarella juniperi, Leptosciarella multispinosa, Leptosciarella opaca, Leptosciarella pilosa, Leptosciarella subcoarctata, Leptosciarella subspinulosa, Leptosciarella trochanterata, Leptosciarella yerburyi

Key to subgenera and species

The key to the subgenera is based on Mohrig & Menzel 1997: 44[4] completed by Mohrig 2003: 7[5]. The key for the species will be added subsequently.

Key for Leptosciarella — Kai Heller
Geographic Scope: world — Audience: students, scientists — Collaboration: open — Status: under construction — Edited by: Kai Heller
1
Wing membrane at least apically with macrotrichia. 
  Hirtipennia
Wing membrane without macrotrichia.   ► 2
2 (1)
Gonostyli apically rounded, without apical tooth, bulged on the inner side. 
  Trichosiopsis
Gonostyli simple, with apical tooth.   ► 3
3 (2)
Gonostyli apically truncate, with strong apical tooth and coarse spines. 
  Leptospina
Gonostyli not truncate, with shorter apical tooth and spines.   ► 4
4 (3)
Gonostyli apically without awl-like spines. Transition of basal part to neck of antennal bottleneck-like. 
  Protosciarella
Gonostyli apically with short awl-like spines. Transition of basal part to neck of antennal segments pronounced. 
  Leptosciarella s. str.

References

  1. Tuomikoski, R. 1960: Zur Kenntnis der Sciariden (Dipt.) Finnlands. Annales Zoologici Societatis Zoologicae Botanicae Fennicae “Vanamo”, 21, 1–164.
  2. Menzel, F.; Mohrig, W. 2000: Revision der paläarktischen Trauermücken (Diptera: Sciaridae). Studia dipterologica Supplement 6, 1-761. AMPYX-Verlag, Halle.
  3. Amorim, D.S. 1992: A catalogue of the family Sciaridae (Diptera) of the Americas south of the United States. Revista Brasileira de Entomologia, 36, 55–77.
  4. 4.0 4.1 4.2 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.
  5. 5.0 5.1 Mohrig, W. 2003: Black fungus gnats of Central America. Part I. (Diptera, Sciaridae). Beiträge zur Entomologie, 53(1), 1–69.
  6. Rudzinski, H.-G. 2005: Beitrag zur Trauermückenfauna Taiwans Teil II: Gattungen Sciara, Schwenckfeldina, Trichosia, Leptosciarella, Baeosciara und Trichosillana gen. nov. (Diptera Nematocera: Sciaridae). Entomofauna, 26, 253–280.