Chrysotus saigusai Negrobov, Kumazawa & Tago, 2016

Negrobov, Oleg P., Kumazawa, Tatsunori, Tago, Toshihiro & Fursov, Viktor N., 2016, Species of the genus Chrysotus Meigen, 1824 (Diptera: Dolichopodidae) from Japan, with descriptions of two new species, European Journal of Taxonomy 197, pp. 1-15 : 6-8

Chrysotus saigusai Negrobov, Kumazawa & Tago sp. nov.

urn:lsid:zoobank.org:act:D4B29EEA-1EF5-4210-A383-94EFE3ED35EA

Figs 2 , 5B

Chrysotus sp. 1t – Tago 2010: 43.

Diagnosis

Face narrow, width in lower part less than distance between ocellar bristles; antenna black; postpedicel transverse-oval, with a triangular tip; lower postocular setae white; fore coxa with black hairs; femora mainly green-brown; mid tibia with 2 anterodorsal and 2 posterodorsal setae; hind femur with long setae, hind tibia with short hairs; phallus with two lateral processes on tip.

Etymology

The species is named after the famous dipterologist Dr. Toyohei Saigusа from Japan.

Material examined

Holotype

JAPAN: Ƌ, Honshu, Aichi Prefecture, Kasugai , Univ. Experim. Farm, on grass near ponds, 19 Jun. 2004, leg. V. Fursov ( ZIN).

Paratypes

JAPAN: 4 ƋƋ, same data as holotype, leg. V. Fursov; 5 ƋƋ, Honshu, Nagoya, Higashiyama Park, oak forest, 2 May 1999, leg. V. Fursov; 14 ƋƋ, Honshu, Nagoya, Higashiyama Park, oak forest, 11 Aug. 1999, leg. V. Fursov; 1 Ƌ, Ibaraki Prefecture, Tsukuba, Sakuragaoka, swept grass near forest, 26 Apr. 1997, leg. V. Fursov; 2 ƋƋ, Ibaraki Prefecture, Tsukuba, Sakuragaoka, 3 May 1997, leg. V. Fursov; 2 ƋƋ, Ibaraki Prefecture, Tsukuba, Sakuragaoka, 5 May 1997, leg. V. Fursov; 2 ƋƋ, Ibaraki Prefecture, Tsukuba, Yaware, near rice fields, 17 Jun. 1997, leg. V. Fursov; 4 ƋƋ, Ibaraki Prefecture, Tsukuba, Yaware, 25 Jun. 1997, leg. V. Fursov; 2 ƋƋ, Ibaraki Prefecture, Tsukuba, Hanare, near rice fields, 14 Jun. 1997, leg. V. Fursov; 2 ƋƋ, Honshu, Nagoya, Midori-ku, Odaka Green Park, 5 May 1999, leg. V. Fursov; 1 Ƌ, Honshu, Nagoya, Nissin-shi, 5 Apr. 1999, leg. V. Fursov ( IZU, VSU, ZIN); 1 Ƌ, Tochigi Prefecture, Kanuma City, Shimokasuo, 8 Jul. 2012, leg. T. Tago; 1 Ƌ, Saitama Prefecture, Saitama City, Akigase Park, Sakura wood, 1 Oct. 2011, leg. T. Tago ( OMNH, Japan); 1 Ƌ, Kuril Islands, island Kunashir, Alekhine, 8–12 Aug. 1984, leg. Kirejtshuk ( ZIN).

Description

Male

MEASUREMENTS. Body length: 1.2–1.3 mm, wing length: 1.2–1.3 mm.

HEAD. Frons green with purple tinge, without pollen. Face narrow, its width narrower than the width between ocellar bristles in lower part. Frons green at the top, with pollinosity on the bottom. Antenna black, postpedicel small, a right-angled triangular, its length about equal to its height. Arista subapical, with short hairs. Length of arista approximately five times longer than length of postpedicel. Proboscis and palpus brown with black hairs without pollen. Lower postocular setae pale.

THORAX. Metallic green, scutum with bronze tinge and without pollen. Pleura with pollen, propleuron with 1–2 setae. 5 pairs of strong dorsocentral setae. Acrostichal setae long, irregular 6–7 pairs, arranged in two rows. Scutellum with 2 long and 2 short lateral setae.

LEG. All coxae dark; femora mostly dark, except apical part of fore femur, apical and basal part of mid femur and basal part of hind femur yellow; trochanters yellow or yellowish-brown; fore and mid tibiae yellow, hind tibia yellowish-brown; most part of mid and hind tarsi yellow, basal parts hind tarsus yellowish-brown. Coxae with dark hairs and setae. Fore femur with 3 long preapical setae. Fore tibia with 1 anterodorsal seta and short posteroventral hairs. Fore tarsus with short hairs. Ratio of fore tibia and tarsus (from 1 to 5) 2.8: 1.7: 0.7: 0.5: 0.4: 0.5. Mid femora with 3 short preapical setae and short anteroventral hairs. Mid tibia with 2 anterodorsal and 2 short posterodorsal setae. Ratio of mid tibia and tarsus (from 1 to 5) 3.8: 2.1: 1.0: 0.7: 0.5: 0.4. Hind femora with 4 long preapical setae and short anteroventral hairs on entire length of femur. Hind tibia with 4 short anterodorsal, 3 posterdorsal setae and short erect anteroventral hairs, their length approximately equal to the diameter of tibia. First segment of hind tarsus with short erect hairs. Ratio of hind tibia and tarsus (from 1 to 5) 4.4: 1.5: 1.2: 0.7: 0.5: 0.4.

WING. Hyaline with dark veins; R 4+5 and M 1+2 slightly divergent at apex. Length of costal section between R 4+5 and M 1+2 about twice longer than that between R 2+3 and R 4+5; m-cu distinctly shorter than apical part of CuA 1. Halter and cilia on lower calypter yellow.

ABDOMEN. Metallic green, pollinose laterally, covered with black hairs. Epandrium oval in the basal part with the small projection; apical tip of surstylus bent. Phallus with two lateral processes at apex. Cercus oval with black hairs.

Female

Unknown.

Addition to the key

In the key to the Palearctic species of Chrysotus ( Negrobov et al. 2000) , the new species Chrysotus saigusаi Negrobov, Kumazawa & Tago sp. nov. runs to Chrysotus defensus Negrobov & Maslova, 2000 and can be distinguished from the latter by the following characters:

58. Basal part of hind femur and hind trochanter black. The phallus before the apex with two long dorsal processes. Caucasus … ……………………………… Ch. defensus Negrobov & Maslova, 2000

– Basal part of hind femur and hind trochanter yellow. The phallus before the apex with short lateral processes ………………………………….… Ch. saigusai Negrobov, Kumazawa & Tago sp. nov.

Figures

Fig. 2. Chrysotus saigusai Negrobov, Kumazawa & Tago sp. nov., Ƌ, paratype, coll. 8 Jul. 2012. A. Hypopygium, lateral view. B. Hypopygium, ventral view. C. Antenna. D. Apex of phallus, lateral view. E. Cerci, ventral view.

Fig. 5. Male habitus, lateral view. A. Chrysotus masunagai Negrobov, Kumazawa & Tago sp. nov., Ƌ, paratype, coll. 15 May 2010. B. Chrysotus saigusai Negrobov, Kumazawa & Tago sp. nov., Ƌ, paratype, coll. 8 Jul. 2012.