New species of Hercostomus Loew, 1857 from Afrotropics (Diptera: Dolichopodidae) and key to Afrotropical fauna
Grichanov, Igor Ya.
European Journal of Taxonomy
2020
2020-10-22
722
16
36
8GV6B
Grichanov, 2020
Grichanov
2020
[595,894,1666,1693]
Insecta
Dolichopodidae
Hercostomus
GBIF
Animalia
Diptera
9
25
Arthropoda
species
koshelevae
sp. nov.
Fig. 4
Diagnosis The new species is sister species to H. sanipass sp. nov., differing distinctly in its smaller size, narrower face, lighter colored legs, weakly widened fore tarsomere 3. The hypopygia are rather similar in the two species. Nevertheless, the proximal arm at apex of ventral lobe of postgonite in H. koshelevae sp. nov.is always thinner than that in H. sanipass. The long basolateral cercal lobe in males of both species is very peculiar, being much shorter in males of close species with modified fore tarsus.
Etymology The species is named for the Russian entomologist, Dr. Oksana Kosheleva (VIZR, St. Petersburg).
Material examined Holotype SOUTH AFRICA• ♂; KwaZulu-Natal, Balgowan, “Yellowoods”; 29°24′′ S, 30°03′′ E; 1300 ma.s.l.; 31 Dec. 1982; J. Manningleg.; high forest, deeply shaded stream herbs; NMSA. Paratypes SOUTH AFRICA– KwaZulu-Natal• 4 ♂♂, 1 ♀; same data as for the holotype• 1 ♂; Pietermaritzburg, Town Bush, 2930Cb; Nov. 1971; M.E. Irwinleg.; terminalia dissected and stored in glycerin in microvials pinned with the specimen; NMSA• 1 ♀; Richmond District, Pateni, 2930Cc; 30°09′′ S, 29°56′′ E; 18 Nov. 1971; B. and P. Stuckenbergleg.; temp. forest; NMSA• 1 ♂; Deepdale, Umkomaas Valley; 29°48′ S, 29°58′ E; May 1959; B. and P. Stuckenbergleg.; terminalia dissected and stored in glycerin in microvials pinned with the specimen; NMSA• 1 ♂, 1 ♀; Royal Natal National Park, Forest stream rocks; 1828.8 ma.s.l.[alt. 6000’]; 19 Jan. 1987; J. Manningleg.; terminalia dissected and stored in glycerin in microvials pinned with the specimen; NMSA• 1 ♂; Cathedral Peak Natural Reserve, Rainbow Gorge; 1480 ma.s.l.; 28°57.6′ S, 29°13.61′ E; 29 May – 21 Sep. 2006; Mostovskileg.; malaise trap; NMSA. – Eastern Cape• 1 ♂, 1 ♀; Storms River Pass, Tsitsikama Range; 33°59′ S, 23°55′ E; 12–13 Oct. 1959; B. and P. Stuckenbergleg; indigenous forest; terminalia dissected and stored in glycerin in microvials pinned with the specimen; NMSA• 1 ♀; Hogsback, 3226Db; 32°35′ S, 26°57′ E; 13–16 Dec. 1985; J. and B. Londtleg.; forest and forest margins; NMSA. – Western Cape• 1 ♂; Groeneweide Forest, Saasweld Forest margin; 33°57′ S, 22°32′ E; ca 150 ma.s.l.; 9 Sep. 1993; D. and C. Barracloughleg.; terminalia dissected and stored in glycerin in microvials pinned with the specimen; NMSA. – Mpumalanga• 1 ♂; E. Transvaal, Marieskop[Forest Reserve]; Oct. 1956; B. Stuckenbergleg.; terminalia dissected and stored in glycerin in microvials pinned with the specimen; NMSA.
Description Male( Fig. 4) Similar to H. sanipass sp. nov.in all respects except as noted. MEASUREMENTS (in mm). Body length 3.6–4.1; antenna length 1; wing length 3.9; wing width 1.4 ( Fig. 4A). HEAD. Face gradually narrowed towards palpi, 4.9 × as high as wide in middle, under antennae 1.5 × as wide as width of postpedicel, at clypeus half as wide as width of postpedicel. Antennal postpedicel 1.3 × longer than high ( Fig. 4B). Length ratio of scape to pedicel to postpedicel to stylus (1 st– 2 ndsegments), 23/10/23/15/50. Palpus, proboscis moderately small, yellow, with short black setae; palpus with 1 black bristle. THORAX. Mostly greenish-black, greyish pollinose; metepimeron dirty yellow. LEGS. including coxae mostly light yellow; mid coxa brownish laterally; hind femur brownish at extreme apex; tarsi black from tip of basitarsus, fore tarsomere 5 yellow. Fore tarsomere 3 flattened and slightly widened, with dorsal comb of short black setulae; tarsomeres 4–5 with semi-accumbent dorsal hairs, tarsomere 4 with black hairs, tarsomere 5 with white hairs ( Fig. 4C). Length of fore femur, tibia and tarsomeres 1–5 = 1.15 mm, 1.29 mm, 0.65 mm, 0.53 mm, 0.33 mm, 0.14 mm, 0.16 mm. Length of mid femur, tibia and tarsomeres 1–5 = 1.38 mm, 1.8 mm, 1.01 mm, 0.49 mm, 0.4 mm, 0.22 mm, 0.16 mm. Length of hind femur, tibia and tarsomeres 1–5 = 1.75 mm, 2.16 mm, 0.58 mm, 0.74 mm, 0.5 mm, 0.26 mm, 0.2 mm. WINGS. simple, greyish, almost hyaline, veins brown. Ratio of part of costa between R 2+3and R 4+5to between R 4+5and M 1+2, 24/7. Ratio of dm-m to distal part of M 4, 39/60. GENITALIA. ( Fig. 4D) with epandrium mostly yellow, brown at base. Hypandrium mid-ventral, with short base, 4 long thin lobes of different lengths, widths. Phallus thin, projected. Distoventral epandrial lobe as short rounded prominence, fused to epandrium, with 1 short and 1 long seta. Surstylus yellow, bilobate; ventral lobe broad, simple, ¾ length of dorsal lobe, with 1 subapical seta; dorsal lobe of surstylus widened in distal half, with short narrow process at apex, several subapical setulae, 1 strong mid-dorsal seta. Distal lobe of postgonite as long as ventral lobe of surstylus, narrow, broad and pointed at apex. Ventral lobe of postgonite ( Fig. 4E) strongly sclerotized, with 2 long arms (anterior, posterior) at apex forming letter V, 2 short symmetrical processes between them, covered with denticles on ventral side. Cercus ( Fig. 4F) broad, light yellow, densely covered with short light hairs, longer at apex; cercus with basolateral lobe, longer than cercus, densely covered with long setae, with distolateral narrow process bearing 3 thick hook-tipped setae at apex; 2 strong setae proximal to process, 3 strong setae at apex of cercus. Fig. 4. Hercostomus koshelevae sp. nov., ♂, holotype (MNSA; A–C); ♂, paratype, Town Bush (MNSA; D–F). A. Habitus. B. Antenna. C. Fore tarsus. D. Hypopygium, right lateral view. E. Distoventral appendages of epandrium. F. Cercus. Female Similar to male except lacking male secondary sexual characters.
Ecology According to typespecimen labels, imagos inhabit rocks in mountain streams, being common in forests.
Distribution South Africa.
2898013314
high forest, deeply shaded stream herbs
1982-12-31
NMSA
J. Manning
South Africa
1300
Balgowan
10
26
1
KwaZulu-Natal
holotype
2898013305
[189,1116,596,622]
high forest, deeply shaded stream herbs
1982-12-31
NMSA
J. Manning
South Africa
1300
KwaZulu-Natal
10
26
5
1
4
KwaZulu-Natal
paratype
2898013324
1971-11
NMSA
M. E. Irwin
South Africa
Pietermaritzburg
Town Bush
Town Bush
10
26
1
1
KwaZulu-Natal
paratype
2898013320
temp. forest
1971-11-18
NMSA
B. and P. Stuckenberg
South Africa
Richmond District
Pateni
Pateni
10
26
1
1
KwaZulu-Natal
paratype
2898013316
1959-05
NMSA
B. and P. Stuckenberg
South Africa
-29.8
Umkomaas Valley
1225
29.966667
Deepdale
10
26
1
1
KwaZulu-Natal
paratype
2898013322
1987-01-19
NMSA
J. Manning
South Africa
1829
Forest stream rocks
Royal Natal National Park
10
26
2
1
1
KwaZulu-Natal
paratype
2898013323
2006-05-29
2006-09-21
2006-05-29
malaise trap
NMSA
Mostovski
South Africa
1480
-28.96
Rainbow Gorge
92
29.226833
Cathedral Peak Natural Reserve
10
26
1
1
KwaZulu-Natal
paratype
2898013308
1959-10-12
1959-10-13
1959-10-12
NMSA
B. and P. Stuckenberg
South Africa
-33.983334
Storms River Pass
1202
23.916666
River Pass
10
26
2
1
1
Eastern Cape
paratype
2898013321
forest and forest margins
1985-12-13
1985-12-16
1985-12-13
NMSA
J. and B. Londt
South Africa
-32.583332
Hogsback
1209
26.95
Hogsback
10
26
1
1
Eastern Cape
paratype
2898013310
1993-09-09
NMSA
D. and C. Barraclough
South Africa
150
-33.95
Saasweld Forest margin
1202
22.533333
Groeneweide Forest
10
26
1
1
Western Cape
paratype
2898013328
1956-10
NMSA
B. Stuckenberg
South Africa
E. Transvaal
10
26
1
1
Mpumalanga
paratype