Antrops truncipennis Enderlein

KITS, JOEL H. & MARSHALL, STEPHEN A., 2013, Generic classification of the Archiborborinae (Diptera: Sphaeroceridae), with a revision of Antrops Enderlein, Coloantrops gen. nov., Maculantrops gen. nov., Photoantrops gen. nov., and Poecilantrops gen. nov. , Zootaxa 3704 (1), pp. 1-113 : 48

publication ID	https://doi.org/ 10.11646/zootaxa.3704.1.1
publication LSID	lsid:zoobank.org:pub:341ED5F6-2DCA-4E73-83D6-389DF0DD347F
persistent identifier	https://treatment.plazi.org/id/03A18780-C667-FFAC-0DD3-D98AFA1DF8D8
treatment provided by	Felipe
scientific name	Antrops truncipennis Enderlein
status

Treatment

Antrops truncipennis Enderlein View in CoL

( Figs. 7 View FIGURES 7–12 , 61 View FIGURES 61–64 , 209 View FIGURES 204–212 )

Antrops truncipennis Enderlein 1909: 228 View in CoL

Description. Head brown, antenna, clypeus, and maxillary palp yellow, almost entirely covered with short setae. Mostly covered with microtomentum, interfrontal plates shiny in male. Ocelli absent. Frons and lateral portions of occiput covered with setae. Bristles on frons very short and thick in male, slightly longer and thinner in female. Subvibrissal ridge with 3–5 setae below vibrissa, none enlarged, anterior genal bristle not enlarged. Head shape modified, length of frons about 2X head height, projecting over face, gena height slightly greater than eye height. Labellum with 18–20 pseudotrachea.

Thorax brown, covered with microtomentum. Postpronotum with 1 longer lateral bristle and 1 shorter medial bristle, notopleuron squeezed posteriorly, with 2 bristles, scutellum greatly reduced, not projecting at all beyond mediotergite, with 2 bristles, other bristles absent or indistinguishable from surrounding setae. Halter not developed.

Legs brown. Fore first tarsomere with a broad apicoventral spur in male. Mid tibia with anterodorsal row of very short stout bristles, 1 anteroventral, 1 or 2 posteroventral bristles, 7 apical bristles. Hind tibia with 1 anteroventral bristle, 3 apicoventral bristles.

Wing brown, membrane opaque. Shape blade-like, in male longer than thorax, strongly falcate, in female about as long as thorax, pointed ( Fig. 7 View FIGURES 7–12 ).

Abdomen with sternites and tergites brown, heavily sclerotized, covered with microtomentum. Pleural setae short anteriorly, long on posterior segments.

Male postabdomen: Sternite 5 simple, subrectangular, wider than long. Surstylus long, widest medially, thin apically, posterior face entirely covered with long setae. Postgonite with lobes moderately separated, posterior lobe long and pointed, anterior lobe short and rounded. Basiphallus long, with short, broad epiphallus, long, thin preepiphallus. Distiphallus with a short smooth dorsal tube, long ventral distal extension ( Fig. 61 View FIGURES 61–64 ).

Female postabdomen: Tergites 6–7 not sclerotized medially, moderately sclerotized along anterior and lateral margins, with 3 weakly sclerotized anterior strips. Tergite 8 with anterior margin notched, covered with microtomentum and setae. Epiproct with long anterior arms, covered with setae. Cerci normal. Sternites 6–7 not sclerotized medially, moderately sclerotized along anterior and lateral margins, with 2 weakly sclerotized anterior strips. Sclerites of sternite 8 subrectangular, with basal half depressed, shiny, distal half with microtomentum and setae. Hypoproct trapezoidal, with a circular anteromedial depression. Spermathecae about as long as wide, with a deep apical invagination and short basal invagination, sclerotized duct about as long as spermathecae.

Type material. Syntypes: CHILE: Cape Horn archipelago, 1885, Hyades & Hahn (1 ♂, 1 ♀, MNHN; not examined) .

Other material examined. ARGENTINA: Tierra del Fuego: Isla de los Estados, Bahía Blossom , 10 May 1971, O.S. Flint & G.F. Hevel (2 ♀, USNM) ; Isla de los Estados, Bahía Colnett , 25 May 1971, O.S. Flint & G.F. Hevel (17 ♂, 15 ♀, USNM) ; Isla de los Estados, Puerto Pte. Roca , 22–23 May 1971, O.S. Flint & G.F. Hevel (2 ♀, USNM) . FALKLAND ISLANDS: Falkland Is. , [no date], R. Vallentin (1 ♂, 1 ♀, BMNH) . SOUTH GEORGIA ISLANDS: Bird I., Freshwater Bay , ex. rotting kelp, 14 Feb 1963, H.B. Clegg (2 ♂, 6 ♀, 1, BPBM) ; Bird I., Iceberg Point , under rocks on beach, hand coll., 24 Apr 1963, H.B. Clegg (1 ♂, 4 ♀, BPBM) ; Bird I., Landing Beach , under rocks, 24 Apr 1963, H.B. Clegg (19 ♂, 15 ♀, BPBM) ; Bird I., Stinker Cape , under stones on beach, 19 Apr 1963, H.B. Clegg (2 ♂, 2 ♀, BPBM) ; South Georgia I., Barff Peninsula, Sörling Valley , under rotting kelp on beach, 21 Jan 1964, H.B. Clegg (7 ♂, 3 ♀, BPBM) ; South Georgia I., Hound Bay , shoreline, 21 Jan 1982, M. Vogel (1 ♂, 1 ♀, USNM) .

Comments. This species occurs on several widely separated oceanic islands. There seem to be two alternate explanations for such a wide distribution of a brachypterous fly: anthropogenic dispersal, or oceanic rafting, perhaps on floating masses of the kelp that this species feeds on. At present there is insufficient data to distinguish between these possibilities. The reduced wing, tiny eye, and extensive covering of setae on the head are distinctive.