Difference between revisions of "Trichosiopsis fuscipalpa diutina"

Latest revision as of 19:23, 1 January 2021

Taxonavigation

Ordo: Diptera
Familia: Sciaridae
Genus: Trichosiopsis
Species: Trichosiopsis fuscipalpa

Name

Trichosiopsis fuscipalpa diutina  unpublished

Type material

Holotype: ♂, 17.5.–22.5.2012, Malaise trap, leg. Sellmayer, BIOUG05209-C02 in ZMUC

Type locality

Germany, Bavaria, Nationalpark Bayerischer Wald

Barcoded material

Description (male)

Head. Eye bridge 4 rows of facets. Antenna unicolour. LW-index of 4^th flagellomere 3.2–3.6; neck 0.3–0.4 × segment width; transition of basal part to neck pronounced. Colour of neck unicolour. Antennal setae shorter than segment width; of normal strength; dense; salient. Palpus darkened; of normal length; palpomeres 3. First palpomere of normal shape; with 3–5 setae; with only sparse sensilla. Second palpomere short and oval. Third palpomere as long as first. Thorax. Colour brown. Notum unicolour. Thoracic setae long and strong; brown. Posterior pronotum bare, or setose. Postpronotal setae 0–4; fine. Mesothoracic sclerites bare. Legs. Colour yellow. Hind coxa of same colour as femora. Setae on front coxa black, or darkened. Front tibial organ as patch of setae; dark; front tibial organ not bordered. Tibial setae on hind legs weak and inconspicuous, or normal, shorter than tibial width. Tibial spurs of equal length. Claws untoothed. Wing. Wing slightly darkened; with weakly developed anal lobe. Wing membrane without macrotrichia. Wing venation weak, with faint stM. M-fork of normal shape. R₁ ending at or slightly before base of m-fork; posterior veins with macrotrichia; stM mostly with macrotrichia; CuA₁ and CuA₂ mostly with macrotrichia; bM bare; r-m bare, or with few setae; bM:r-M 0.45–0.65; st-Cu:bM 0.6–0.75; R₁:R 1.1–1.5; c:w 0.68–0.77. Halter darkened; of normal length. Abdomen. Abdominal setae strong; dense; on tergites black; on sternites black. Hypopygium concolour with abdomen; LW-index 0.6–0.72. Base of gonocoxites with weak setae, or with strong setae; gonocoxites broadly separated; inner margin of gonocoxites typically U-shaped; inner membrane of hypopygium scarcely setose; ventral margin of gonocoxite with short setae. Gonostylus elongate; LW-index 1.85–2.05; Inner margin concave; apex equally rounded, or with one obtuse angle. Apical tooth present; without internal structure; of medium strength; LW-Index 1.5–2.2. Awl-like setae normal; present beneath apical tooth. Megasetae absent. Whiplash-hair absent. Tegmen 0.62–0.8 × longer than broad; rectangular with rounded edges; without special features; central process absent. Length of ejaculatory apodeme/hypopygium 32–40 %. Field with aedeagal teeth inconspicuous. Measurements. Body size 3–3.8 mm. Hind tibia 1.6–1.75 mm.

Diagnosis

This subspecies is based on its unique COI sequence. Trichosiopsis diutina is best recognized by the very long antenna and the broad wings with an inconspicuous anal lobe. The gonostylus generally appears apically rounded with a flat mesial side. This character, however, depends on the mounting position and is not always clearly visible.

DNA Barcoding

The COI sequence is assigned to BIN BOLD:ACE2641 (average distance 0.06%, max. 0.15%, n=5, K2P: 5.26%).

Discussion

It has long been noticed, that there existed different forms of Tr. fuscipalpa (Heller 2004^[1]: 241). The form with very long antennae and a conspicuously roundish gonostylus was the dominant species of the whole genus in forests in Northern Germany. The specimens are matching morphologically very well with Tr. fuscipalpa diutina. However, all material, which is currently on BOLD, was collected in montane regions of Southern Germany, whereas recently collected specimens from forests in Northern Germany belong genetically all to Trichosiopsis fuscipalpa fuscipalpa. Either there was a species shift in the course of the last 30 years or the observed morphological differences are not reliable. This is the main reason, why Tr. fuscipalpa diutina is not yet treated as a distinct species despite of its high K2P of more than 5%.

Etymology

lat. diutinus = tedious; the name refers to the long time it took (and still takes) to finally correctly identify this taxon.

Distribution

Germany.

Images

Figure 1. Trichosiopsis fuscipalpa diutina male, habitus, scale 1.0 mm  Figure 2. Trichosiopsis fuscipalpa diutina male, hypopygium, scale 0.1 mm  Figure 3. Trichosiopsis fuscipalpa diutina male, gonostylus (ventral view), scale 0.1 mm  Figure 4. Trichosiopsis fuscipalpa diutina male, aedeagal complex, scale 0.1 mm  Figure 5. Trichosiopsis fuscipalpa diutina male, 4th antennal flagellar segment, scale 0.1 mm  Figure 6. Trichosiopsis fuscipalpa diutina male, palpus, scale 0.1 mm  Figure 7. Trichosiopsis fuscipalpa diutina male, wing, scale 1.0 mm

References

1. ↑ Heller, K. 2004: Eine Bestandsaufnahme der Sciaridae (Diptera) Schleswig-Holsteins mit Ergänzungen und Korrekturen zum bisher bekannten Arteninventar. Faunistisch-Ökologische Mitteilungen, 8, 233–257.