Nemotelus (Nemotelus) infortunatus, Kahanpää, Jere, 2010

Kahanpää, Jere, 2010, Finnish species of Nemotelus (Diptera: Stratiomyidae), with description of a new species, Zootaxa 2401, pp. 30-40 : 33-34

Nemotelus (Nemotelus) infortunatus sp. nov.

( Figures 2 , 8 , 13–16 )

Material examined. HOLOTYPE 3 Kirjavalaks (J. Sahlberg). [ Russia, Republic of Karelia, Sortavala district, Kirjavalahti village].

PARATYPES. Finland N: 1Ƥ Mäntsälä (A. Palmén) [year 1860]. Sb: 1Ƥ Tuovilanlaks (A. Palmén) [Maaninka, Tuovilanlahti, year 1865]. Kb: 13 Ilomants (Woldstedt) [Ilomantsi, year 1865]; 1Ƥ Ilomants (Grönvik) [year 1865]. Kl: 1Ƥ Parikkala/59 (J. Sahlberg). Russia 131Ƥ Kirjavalaks (J. Sahlberg); 1Ƥ Sordavala (Woldstedt) [Karelia, Sortavala]; 1Ƥ Svätnavlok/318. (J. Sahlberg) [Karelia, Svyatnavolok, 6.VII.1869].

The type material is deposited in the Zoological Museum of the Finnish Museum of Natural History, Helsinki, Finland.

Description. Male. Head. Eyes very large, bare or with very short and sparse pilosity, round in profile, separated by a narrow frontal vitta (as wide as the anterior ocellus). Lower eye facets much smaller than upper facets. Rostrum short, rostral index (length of rostrum from eye margin to tip divided by the eye diameter) 0.27–0.31 (n=3), tip somewhat downward curved. Pilosity on rostrum sparse, mostly white. Genae narrow, almost hidden in profile. Antenna short, black, first flagellomere short-oval, inserted at middle of rostrum. Colour: Ground colour black. Upper half of frons with two small, pale yellow, triangular spots separated by a narrow black line. Tip of rostrum brown.

Thorax. Ground colour black with a slight metallic blue tint. Posterior third of postpronotum pale yellow. Subnotopleural stripe narrow, slightly widened towards wing base. Postalar calli dark brown. Pilosity on mesonotum and pleurae silver-white.

Wings. Wings almost hyaline, membrane slightly whitish. Stronger wing veins yellow. R4+5 apically forked (i.e. R4 and R5 reach the wing margin independently). Lower calypter greyish brown, hair fringe whitish. Knob of haltere white, stem brown.

Legs. Coxae and trochanters black. Femora black with yellow apices. Tibiae dark, bases and apices yellow. Tarsi yellow.

Abdomen. Abdomen dorsally white with a black pattern. Tergite 1 (T1) black, only lateral thirds of the posterior margin are white. T2 white, anterior margin medially black. T3 white, anterolateral corners with small black spots. T4 & T5 with broad black transverse bands, only posterior 1/2–1/3 and lateral margins white. T6 white with black sublateral spots. Sternites predominantly black, sternite 2 with a medial white spot and sternites 3–5 with narrow white bands along posterior margins. Abdominal pilosity sparse and mostly white, dark areas with some black setulae. Male genitalia: see Figs. 13–16 .

Measurements. Body length 4.7–4.8 mm, wing length 4.3–4.6 mm (n=3).

Female. Like the male with the following differences: Eyes widely separated (width of frons 1.6 times eye width in dorsal view). Rostrum longer, rostral index 0.46–0.51 (n=5). Frons with a pair of white oval or shorttriangular spots. Abdomen predominantly black, pale spots white to pale yellow. T2–T4 with pale posteromedial triangles and posterolateral corners. Lateral margins of these segments very narrowly pale. Lateral and distal margins of T5 pale. Distal margin of T6 pale. Sternites as in males but pale areas smaller or absent. Body length 4.2–4.9 mm, wing length 3.7–4.3 mm (n=7).

Etymology. Specific epithet is derived from Latin, infortunatus , infortunate, referring to the apparent decline of the species in Finland.

Comments. The type material was collected in the second half of the 19th century from the Russian Republic of Karelia and southern to eastern Finland. Nothing is known about the biology of this species. All known sites are far from the Baltic coast or salt deposits.

Figures

FIGURES 1 – 3. Nemotelus males in a) dorsal view, b) lateral view. 1. N. nigrinus Fallén. 2. N. infortunatus sp. nov. 3. N. notatus Zetterstedt.

FIGURES 7 – 9. Nemotelus females in a) dorsal view, b) lateral view. 7. N. nigrinus Fallén. 8. N. infortunatus sp. nov. 9. N. notatus Zetterstedt.

FIGURES 13 – 16. Nemotelus infortunatus sp. nov.: 13. Hypopygium, dorsal part (epandium, proctiger and cerci) in dorsal view. 14. Hypopygium, ventral part in dorsal view, dorsal part and aedeagal complex removed. 15. Aedeagal complex in dorsal view. 16. Aedeagal complex in lateral view.