Achradocera excavata ( Van Duzee, 1924 )

Quevedo, Lucas, Capellari, Renato S. & Lamas, Carlos José E., 2024, Taxonomic revision of Achradocera Becker (Diptera: Dolichopodidae), with description of two new species, Zootaxa 5519 (3), pp. 301-344 : 320-323

Achradocera excavata ( Van Duzee, 1924)

( Figs 11 , 12 , 26 )

Chrysotus excavatus Van Duzee, 1924: 48 , figs 45–46.

Type-locality: St. Thomas , Virgin Island. Holotype male, USNM.

Diagnosis (male). Postpedicel longer than arista-like stylus; lower postoccipital setae dense. Legs mostly yellow, except for FIII, dorsal surface of FI and FII, TI on apical 3/4, TII on apical half, TIII on basal 1/4 and apical 1/5, and distal tarsi, which are all brown infuscated; TI slightly bent, bearing ventral row of conspicuous setae; TII bulged ventrally in middle, with two ventral rows of setae along swelling, then constricted at apical 1/3 to apex, forming an excavation; IIt 1 arched, with ring of setae at basal 1/3 and anteroventral tubercule within ring; FIII bulged on basal half and concave below, bearing clutch of strong, long setae near middle of anterior surface; IIIt 3–4 concave ventrally. Hypopygium small; surstylus subtriangular, tapered and bearing 1 apical and 1 subapical strong seta; postgonite enlarged and covered by small setae.

Redescription. Similar to A. angustifacies stat. rev., except as noted. Male. Body length: 2.6–2.9 mm. Wing: 2.1–2.3 mm long, 0.7–0.8 mm wide. Antenna. Postpedicel longer than arista-like stylus; FAr, 1.2. Wing. CuAx: 0.5; RMx: 1.36. Leg I. 35, 32, 12, 7, 4, 3, 4. T brownish infuscated pv on apical 2/3, slightly bent beyond basal half, bearing ventral row of setae, ending with distinct apical seta; t 1 entirely yellow. Leg II. 32, 40, 18, 9, 7, 4, 4. T rusty yellow on apical half of dorsal side, bearing anterior seta at basal 1/4, and 4 setae apically (1 av, 1 pv, 1 ad and 1 pd); T ( Fig. 11C ) bulged ventrally in middle, with two ventral rows of short setae along swelling, then constricted at apical 1/3 to apex, forming excavation; t 1 arched with small av tubercule on basal 1/5 with some spines apically; bearing ventral and posterior row of strong decreasing setae, other row ad making circlet of conspicuous setae. Leg III. 42, 46, 15, 9, 5, 4, 3. F bulged on basal half and concave posteriorly, bearing cluster of strong, long setae near middle of anterior surface; T yellow; t 3–4 ventrally concave. Hypopygium. As in Fig. 12A–D , similar to that of A. angustifacies stat. rev.

Female. Unknown.

Distribution. Bahamas, British Virgin Islands, Cuba, Dominican Republic, Jamaica, and Puerto Rico ( Fig. 26 ).

Type material examined. HOLOTYPE ♂, labelled: “ St. Thomas , Vir. Ids. | June 5, 1917. (129) | Harold Morrison ”, “ Type ”, “ Chrysotus excavatus | V.D.” [ USNM].

Additional material examined. Bahamas. 12♂, “ GRAND BAHAMA ISLAND. | Freeport | 20–27 June 1987 | W. E. Steiner, | M. J. & R. Molineaux”, “ Yellow pan trap in | Caribbean pine | and palmetto scrub” [4♂, MZUSP] . British Virgin Islands. 1♂, “BVI: Eustatia Island | N18º30.59′ W64º21.58′ | pan traps / garden area | 28– 30OCT2016, J Runyon” ; 1♂, “BVI: Virgin Gorda | Biras Hill, 90 m | N18º29.74′ W64º21.30′ | Guy’s Trail , pan traps | 11NOV2016, JB Runyon” ; 3♂, “BVI: Virgin Gorda | Bitter End Yacht Club | small ghut, 30m elev | N18º29.74’ W64º21.38’ | 10NOV2016, JB Runyon”. Cuba . 1♂, “ Columbia | Isle of Pines | Cuba VI-27-50 | C.S. 464 | 50- 9283”, “ Chrysotus excavatus VD | Wirth” ; 1♂, “ Aguada Pas. | Cuba Feb. ’15”, “ A. H. Sturtevant | Collection, 1970”. Dominican Republic . 1♂, “DOMINICAN REPUBLIC: | San Cristobal, Centro | Sur Desarrollo Agro-”, “pecuaria ( Sanidad | Vegetal station ) 24. | vii.1987 A. L. Norrbom ” ; 3♂, “DOM. REP.: Prov. Santo | Domingo, Centro de | Tecnologias Agricolas | N18.5400 ºW69.9934º | 22OCT2021, J.B. Runyon ”. Jamaica . 1♂, “ Battersea | Jamaica | Feb. 1910 | F. Thaxter ”, “ALMelander | Collection | 1961” ; 1♂, “JAMAICA | 5 mi. E. Negril | 13 March 1970 | W. W. Wirth | fresh march” ; 3♂, “JAMAICA | AnnottoBay | 25 Feb. 1969 | W. W. Wirth | marsh” ; 2♂, “JAMAICA | WagWaterR. | 25 Feb. 1969 | W. W. Wirth | stream” ; 1♂, “JAMAICA | Pt. Henderson | 24 Feb. 1969 | W. W. Wirth | Bay shore” ; 1♂, “JAMAICA | Kingston | Fresh River | 24 Feb. 1969 | W. W. Wirth ” ; 1♂, “JAMAICA | Runaway Bay | 16-28 Feb 1969 | W. W. Wirth ” ; 2♂, “JAMAICA | Savanna La Mar | 13 March 1970 | W. W. Wirth ”. Puerto Rico . 1♂, “Grape Fruit | III-1-32 ” [handwritten], “ Arecibo P. R. | Anderson | T Faxon ”, “ San Juan | No - 1967”, “1967” [all labels handwritten] ; 4♂, “ PUERTO RICO | Rio Piedras | Agr. Exp. Sta. | 15–18 Oct. 1968 ”, “S. Medina | Gaud. coll.” ; 2♂, “ PUERTO RICO | Arecibo | Cambalache For. | 15–18 Feb. 1969 ”, “S. Medina | Gaud. coll.” ; 1♂, “ PUERTO RICO | Cayey | 15–24 Nov. 1968 | S. Medina Gaud ”. [Most specimens housed in USNM, except those collected by J. Runyon, housed in MTEC] .

Remarks. It is interesting to note that A. excavata and A. apicalis are the only species of Achradocera that can be found in West Indies, and the distribution of these two species are very well delimitated: A. excavata is restricted to the Greater Antilles while A. apicalis to the Lesser Antilles ( Fig. 26 ).

Figures

FIGURE 11. Achradocera excavata. A. Habitus, left lateral. B. Legs, left lateral. C. Legs, focused on TII excavation. D. Head, frontal. E. Thorax, dorsal. Scale bar: A, 1 mm; B–E, 0.2 mm.

FIGURE 12. Achradocera excavata, male genital structures. A. Hypopygium, left lateral. B. Hypopygium, ventral. C. Phallus, ejaculatory apodeme and postgonite, left lateral. D. Postgonite, ventral. Scalebar: 0.1 mm.

FIGURE 26. Distribution map of the genus Achradocera.