Achradocera apicalis ( Aldrich, 1896 )

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 : 308-311

Achradocera apicalis ( Aldrich, 1896)

( Figs 1D , 4 , 5 , 26 )

Chrysotus apicalis Aldrich, 1896: 330 . Type-locality: St. Vincent, West Indies. Lectotype male, USNM.

Diagnosis (male). Postpedicel about half as long as arista-like stylus; lower postoccipital setae dense. Legs mostly yellow, except for FIII, dorsal surface of FI and FII, TIII at basal 1/4 and apical 1/5, and distal tarsi, which are all brown infuscated; TI and TII rusty yellow; fore, mid, and hind legs simple. 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: 2.3–2.5 mm. Wing: 1.9–2.2 mm long, 0.6–0.8 mm wide. Antenna. Postpedicel ( Fig. 4D ) distinctly shorter than arista-like stylus (MSSC); FAr, 0.4. Thorax. About 6 ac pairs. Wing. CuAx ratio, 0.6, RMx ratio, 1.95; lower calypter yellow with fan of about 6 brownish setae; halter pale yellow. Leg I. 29, 32, 15, 7, 5, 4, 4. F with row of about 5 posterior setae at apical 1/4; T rusty yellow. Leg II. 35, 40, 21, 10, 7, 4, 3. F with anterior and posterior row of about 5 setae at apical 1/4; T rusty yellow; basal 1/3 of T with 1 ad seta, apex with 4 setae (1 ad, 1 a, 1 av and 1 pd). Leg III. 42, 45, 15, 9, 6, 4, 3. F with anterior and posterior row of about 5 setae at apical 1/4; T with 4 ad bristles along 3/5 basal, 2 pd at basal half, and 4 apical setae (1 av, 1 pv, 1 ad and 1 pd). Abdomen. Sternite 5 with some conspicuous setae projected backward. Hypopygium. As in Fig. 5A–D , similar to that of A. angustifacies stat. rev.

Female. Similar to males, except by MSSC and as noted. Body length: 2.0– 2.7 mm. Wing: 1.9–2.4 mm long, 0.7–1.0 mm wide. Terminalia. As in generic description (similar to Fig. 24 ).

Distribution. Antigua, Dominica, Montserrat, Nevis, St. Lucia, Tonga and French Polynesia [probably introduced, see Bickel (2000)] ( Fig. 26 ).

Type material examined. LECTOTYPE [designated by Runyon (2020)] ♂, labelled: “ St. Vincent | West Indies ”; “Collection JM Aldrich ”; “Cotype | No.50426 | U.S.N.M.” [red label]; “ Chrysotus apicalis | Type | Ald.” [handwritten] . PARALECTOTYPE: 1♀, same data as holotype [ USNM] .

Additional material examined. Antigua. 6♂, “ Antigua: st. Mary Par. | Passion Village Apts | Valley Church 10 m | 17.05589ºN 61.88764ºW | 17–26 May2022, colored pan traps | J. B. Runyon ”. Dominica . 2♂, “ Clarke Hall | Dominica , BWI | Jan 29 1964 | H. Robinson ”; “ Achradocera apicalis ♂ (Aldrich) ” [handwritten] ; 1♀, “ Dominica, W.I. | Clarke Hall | S- 10 Jan. 1965 | W.W. Wirth | Malaise Trap ”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 2♂, 1♀, “ Dominica, W.I. | Clarke Hall | 11–20 Jan. 1965 | W.W. Wirth | Malaise Trap ”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 2♂, “ Dominica, W.I. | Clarke Hall | 18 Jan. 1965 | W.W. Wirth | Cocoa Trail”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 1♂, “ Dominica, W.I. | Clarke Hall | 1–10 Mar. 1965 | W.W. Wirth | Light Trap ”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 1♂, “ Dominica, W.I. | Clarke Hall Est. | May 7 1966 | R. J. Gagne ”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 3♂, “ Dominica, W.I. | Clarke Hall Est. | June 7 1966 | G. Steyskal”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 1♀, “ Dominica: nr. | Clarke Hall | 10-x-1966 | A.B. Gurney ” . 7♂, 1♀, “Dominica, W.I. | Cabrit Swamp | 22–25 Mar. 1965 | W.W. Wirth ”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” [3♂ and 1♀ housed in MZUSP] . 2♂, “ Dominica, W.I. | Portsmouth | Apr. 1–2, 1966 | R.J. Gagne”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 2♂, “ Dominica | Anse Bouleau | X-10-1964 | P.J. Spangler”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 1♂, “ Dominica, W.I. | Grande Savage | 1 Feb. 1965 | W.W. Wirth”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 1♂, “Dominica, W.I. | Fond Figures R. | 23 Jan. 1965 | W.W. Wirth ”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica”; “ Achradocera apicalis ♂ (Aldrich) ” [handwritten] . 3♂, “ Dominica, W.I. | Springfield | Plantation ”; “18–22/ 23–29.vii.1978 | G.C. Steyskal ”; “Bredin Archbold | Smithsonian Bio. Surv. Dominica” . 1♂, “ Dominica, W.I. | Springfield | Nov. 1967 | N.L.H. Krauss ” . 3♂, 1♀, “ Dominica St. Paul Par. | Springfield Estate | 29 May. 2011 | Fit Trap ” . 2♂, 3♀, “nr Layou | Jan. 27, 1964 ” [handwritten]; “Dominica, BWI | 1964 | H. Robinson ”; “ Achradocera apicalis ♂ (Aldrich) ” [handwritten; label present only on males, one of them marked as “ ♀ ”, but specimen is actually male] . 1♂, 1♀, “ South Chiltern | Feb. 7/8” [handwritten]; “ Dominica , BWI | 1964 | H. Robinson ”; “ Achradocera apicalis ♂ (Aldrich) ” [handwritten; label absent on female specimen’s pin] . 1♂, “ Batali River | Jan 30, 1964 ” [handwritten]; “Dominica, BWI | 1964 | H. Robinson ”; “ Achradocera apicalis ♂ (Aldrich) ” [handwritten]. French Polynesia . 4♂, 5♀, “ French Polynesia | E Bora Bora | 15-vi-1988 | R. Hurley” ; 3♂, 3♀, “ Marquesas, Nuku | Hiva: Toovii | 10–12 Jun 1987, 800 m | Wayne N. Mathis ”; “ Achradocera barbata (Loew) det. Bickel ” [misidentified]. Montserrat . 2♂, 1♀, “ Montserrat: Woodlands | Riverside House. 140 ft | 16º45.985′N, 62º13.341′W | 10–12 Jan 2002, Malaise | Ivie, Marske, Puliafico”; “ Achradocera apicalis (Aldrich) | det. J.B. Runyon 2020 ”. Nevis . 4♂, 1♀, “ Nevis: Par. St. John | small pond, 200 m | N17º07.460′ W62º35.584′ | 26 May 2017 | J.B. Runyon ”. St. Lucia . 4♂, “ St. Lucia: Savannes | Mangrove Res. 0–5 m | N13º45.97′; W60º54.88′ | 3-v-2009 | J.B. Runyon ” . 2♂, 1♀, “ St. Lucia: Micoud Dist. | Escap Community 50 m | concrete drainage ditch | N13º49.92′; W60º53.91′ | 3-v-2009 | J.B. Runyon ” . 1♂, “ St. Lucia : W.I. | Castries | October 1967 | N.L.H. Krauss ”. [specimens from French Polynesia (except R. Hurley specimens) and from Dominica (Bredin Archbold), in USNM; all others in MTEC] .

Remarks. Runyon (2020) discussed in detail the entangled taxonomic history of A. apicalis , which he removed from synonomy with A. barbata , due to characters of the male tarsus I and hypopygium. It is noteworthy that postpedicel size was used by Robinson (1975) to distinguish specimens of A. apicalis from A. barbata . Nevertheless, Bickel (2000) did not consider such differences enough to separate the two species, arguing that postpedicel size is too variable between specimens. However, after analyzing a large number of specimens from different localities, we noted that the size of the postpedicel is consistent in A. apicalis and comparatively shorter than in other species of the genus. Based on this feature, we assume that previous records of A. apicalis from Chile, Ecuador and Mexico are actually records of A. angustifacies stat. rev., A. gimli sp. nov. and A. barbata , respectively.

Figures

FIGURE 1. SEM of the synapomorphies of Achradocera. Achradocera barbata: A. Postgena of head showing ventral flattened postocular setae. B. lateral view of postpedicel. C. Setae of postpedicel and insertion of subapical arista [broken] indicated by red arrow. Achradocera apicalis: D. Head, frontal view.

FIGURE 4. Achradocera apicalis. A. Habitus, left lateral. B. Thorax, dorsal; C. Wing. D. Head, right lateral. Scale bar: A, 1 mm; B–D, 0.2 mm.

FIGURE 5. Achradocera apicalis, male genital structures. A. Hypopygium, left lateral. B. Hypopygium, ventral. C. Phallus, ejaculatory apodeme and postgonite, left lateral. D. Postgonite, ventral. Scale bar: 0.1 mm.

FIGURE 24. Female genital structures of Achradocera arcuata [similar to genitalia of the other species]. A. dorsal view. B. left lateral view. Abbreviation list: cerc, cercus; T8, tergite 8; T9+10, fusion between tergite 9+10; S8, sternite 8. Scale bar: 0.1 mm.

FIGURE 26. Distribution map of the genus Achradocera.