Acidogona stecki Norrbom, 2010

Norrbom, Allen L., Sutton, Bruce D., Steck, Gary J. & Monzón, José, 2010, New genera, species and host plant records of Nearctic and Neotropical Tephritidae (Diptera) 2398, Zootaxa 2398, pp. 1-65 : 6-10

Acidogona stecki Norrbom , new species

Figs. 1–10, 30–32

Diagnosis. This species differs from A. dichromata by its entirely microtrichose scutellum and slightly larger first flagellomere. It differs from both A. dichromata and A. melanura in wing pattern. In the female the pattern is more banded, with fewer hyaline spots. In particular there is a hyaline band from cell br to the posterior wing margin in cell cu 1 and an oblique subapical hyaline band across most of cells r 4+5 and m, sometimes fusing with the marginal spot in cell r 2+3 and extending anteriorly to the apex of vein R 2+3. The marginal hyaline marks in cell r 1 both extend to vein R 4+5, whereas they usually do not in A. melanura and never do so in A. dichromata . The pterostigma and apical part of r 1 are entirely brown, both lacking the subapical yellowish to hyaline spot commonly present in A. dichromata and A. melanura . The wing pattern is strongly sexually dimorphic as in A. dichromata and the pattern in the male resembles that species (e.g., cell dm entirely infuscated), but is more diffuse, with less contrast between the pale and dark parts of the pattern. It differs from both A. dichromata and A. melanura in lacking a subapical hyaline spot in cell br, and the subbasal spot in cell r 4+5 is faint or absent. Males also have less dark brown abdominal markings than in A. dichromata and A. melanura , at most with 1 pair of spots on syntergite 1+2.

Description. Small to moderate sized, body length 3.0– 4.5 mm. Mesonotum length 1.32–1.92 mm. Wing length 3.2–4.4 mm, width 1.2–1.8, ratio 2.30–2.62.

Head ( Figs. 2–3): Yellow except ocellar tubercle and most of occiput dark brown; parafacial occasionally (4 of 13 specimens) with small, faint brown spot aligned with base of antenna. Entirely microtrichose; most setae and setulae dark red brown to black, acuminate. Frons broad, 2.1–2.7 times as broad as width of eye; with numerous fine, black setulae medially and surrounding frontal and orbital setae; 3 frontal setae, anterior 2 closer together, 2 orbital setae, both reclinate; ocellar seta well developed, postocellar seta ca. half as long as ocellar seta; medial vertical seta black, acuminate; facial ridge setulae fine, yellow; genal setulae mostly brown, genal seta brown or yellow; postocular setae mostly yellow, lanceolate, 1–3 sometimes smaller, black, acuminate; setulae of occiput and postgena yellow, lanceolate. Face without medial carina; lunule narrow. Eye large, genal height 0.22–0.26 times eye height. Antennal first flagellomere 1.58–1.93 times as long as wide, 0.37–0.39 times eye height in male, 0.49–0.53 times eye height in female; arista entirely minutely pubescent, more sparsely on distal half. Proboscis large, capitate; palpus broad, oval, with brown and yellow setulae.

Thorax ( Fig. 1): Microtrichose except extreme anteromedial margin of scutum (not visible in dorsal view) and medially on mediotergite; scutum and scutellum entirely microtrichose. Scutum mostly dark brown, appearing tan due to microtrichia, with paired circular dark brown spots at mesal end of transverse suture and surrounding bases of dorsocentral, acrostichal, intra-alar, and supra-alar setae. Postpronotal lobe, posterior part of notopleuron, and small posterolateral area of scutum yellow. Scutellum color variable, sometimes mostly yellow with dark brown spots at bases of setae and often with fifth spot basomedially; sometimes mostly brown, with apical spots connected to basomedial spot and/or to basolateral spots isolating 1–2 paired yellow spots and apical medial spot. Pleuron mostly brown; at least anteroventral half of propleuron, anterior, dorsal, and posterior margins of anepisternum, dorsomedial spot on katepisternum, and katepimeron yellow. Subscutellum and mediotergite dark brown. Following setae well developed, dark red brown to black, acuminate: postpronotal, anterior notopleural, presutural and postsutural supra-alar, intra-alar, postalar, dorsocentral (aligned with or very slightly posterior to postsutural supra-alar seta), acrostichal, and 2 scutellar setae. Posterior notopleural seta short, yellowish, lanceolate; 2–4 brown, acuminate and 2–3 yellowish, lanceolate anepisternal setae; anepimeral seta yellowish, acuminate in male, usually brown (5 of 7 specimens checked) in female; katepisternal seta well developed, yellowish, acuminate. Scutal setulae mostly yellowish, lanceolate; at least a few setulae between and posterior to dorsocentral and postsutural supra-alar setae black, acuminate, usually connected in shallow, inverted V-shaped band across scutum medially aligned with or anterior to dorsocentral seta. Scutellum moderately convex, nonsetulose medially, margin with yellow, lanceolate setulae, at least 1–2 basal to basal seta, usually 1–2 between basal and apical setae, and often with 1–2 setulae between apical setae. Pleural setulae yellow, lanceolate; in single vertical row on propleuron, on posterodorsal half of anepisternum, on katepisternum except anteriorly and on posterior margin, and on anepimeron surrounding anepimeral seta, up to 2/3 as long as seta.

Legs: Entirely yellow. Hind femur with anterodorsal and posterodorsal preapical setae.

Wing ( Figs. 30–32): Pterostigma 0.51–0.58 times length of cell c. Lobe of cell bcu short, 0.20–0.25 times as long as width of cell. Crossvein r-m at 0.61–0.66 distance from bm-cu to dm-cu on vein M. Vein R 1 dorsally without gap in setulae near bend in vein Sc. Vein R 4+5 dorsally with 2–5 setulae basally. Pattern sexually dimorphic. In female ( Figs. 30–31) predominantly pale to moderate brown with hyaline spots, some fused to form bands. Cell c with 2 large quadrate hyaline spots, both extended to anterior and posterior margins and broader than medial brown mark; in 1 female hyaline except basally and apically, without medial brown mark. Pterostigma entirely brown. Cell r 1 with only 2 marginal hyaline marks, both large, extending to vein R 4+5, proximal mark ending slightly distal to crossvein r-m. Cell r 2+3 with subapical marginal hyaline spot, narrowly separated from (3 Guatemalan females) or partially fused with medial spot in cell r 4+5 and proximal mark in cell m to form oblique band. Cell r 4+5 also with large subbasal hyaline spot and sometimes with 1–2 small subapical spots. Cell m with medial hyaline spot, sometimes fused to oblique band, and small subapical spot. Cell br with large subapical hyaline spot, fused with large subbasal spot in cell dm and large medial spot in cell cu 1 to form band. Cell dm sometimes with small anterior subapical hyaline spot (Chiapas female) or posterior subapical hyaline spot (3 Guatemalan females). Cell bm with large medial spot. Cell cu 1 with basal hyaline spot, aligned with similar spot in anal lobe; often with small subapical spot. In male ( Fig. 32) pattern more diffuse, hyaline areas less sharply defined. Cell c hyaline except narrow basal and apical brown areas, and usually also with small anterior medial brown mark. Cell r 1 with 2 marginal hyaline marks, both extending to or almost to vein R 4+5. Cell r 2+3 with isolated subapical marginal hyaline spot. Cell r 4+5 usually with small diffuse subbasal hyaline spot (absent in 1 specimen) and 1–2 small subapical spots. Cell m with diffuse, subhyaline triangular marginal area. Cell cu 1 with large diffuse, irregular, subhyaline area medially.

Abdomen ( Figs. 1, 4): In Guatemalan males entirely yellow (1 specimen) or only with 1 paired sublateral brown spot on syntergite 1+2. In most Guatemalan females ( Fig. 1) yellow with 1 paired sublateral brown spot on syntergite 1+2 and with 1 usually broader paired submedial brown spot on tergites 3–5 and sometimes tergite 6; in 1 Guatemalan female ( Fig. 4) with additional row of sublateral brown spots (more lateral than on syntergite 1+2) on tergites 3–5; in Chiapas female syntergite 1+2 yellow with sublateral brown spots, other tergites mostly brown with narrow, irregular medial yellow area. Entirely sparsely microtrichose except in male to varying extent laterally on tergite 5 and in female on oviscape, most of tergite 6, and narrowly laterally on tergite 5. Setulae mixed black acuminate and white lanceolate; mostly white on syntergite 1+2 except medial to subapical band of black setulae; mostly black on other tergites except mostly white on posterior margins of tergites 3–4 of male and 3–5 of female.

Male terminalia ( Figs. 8–10): Epandrium yellow with posterolateral dark brown spot. Surstyli moderately elongate; lateral surstylus gradually posteriorly curved, blunt apically; medial surstylus as long as and well separated from lateral surstylus, more sharply posteriorly cuved, with 2 subapical prensisetae. Glans ( Fig. 8) small, weakly sclerotized except for single tubelike sclerite.

Female terminalia: Oviscape (measured ventrally from apex of basal medial desclerotized area, which is elongate and slender) 0.60–0.75 mm long, 0.38–0.41 times as long as mesonotum; color variable, often orange except apicoventrally, basodorsally and apicodorsally, frequently with dorsal brown areas connected by medial vitta, in 1 Guatemalan female and Chiapas female entirely dark brown; setulae entirely black acuminate. Eversible membrane ( Fig. 5) with pair of taenia dorsally and ventrally. Aculeus ( Fig. 6) 0.60–0.62 mm long, ca. 5.5 times as long as wide, tapering on distal fourth to sagittate tip ( Fig. 7). 2 spermathecae subspherical, with short slender neck.

Biology. The larvae of A. stecki feed within unopened capitula of Hieracium abscissum Less. ( Asteraceae : Cichorieae ) ( Figs. 61–62). As reported by Goeden & Teerink (1997) for A. dichromata , the larvae of A. stecki form prepuparia which can wiggle and move to a limited extent within the flowerhead.

Distribution. A. stecki is known only from highland locations (> 1850 m elevation) in Guatemala and southern Mexico (Chiapas). Its distribution may be more extensive as its host plant ranges from central Mexico to western Panama at elevations over 1000 m (TROPICOS database).

Type data. Holotype ♂ ( USNM USNMENT00671084 ) , GUATEMALA: Zacapa: road to plateau N of San Lorenzo , 15.0953°N 89.67203°W, 1894 m, emerged 28 Nov 2007 – 21 Jan 2008 reared ex flowerheads of Hieracium abscissum (07G32) collected 18 Nov 2007, B.D. Sutton, G.J. Steck, A.L. Norrbom, J. Monzón . Paratypes: same data as holotype 5♂ 5♀ ( USNM USNMENT00212026 , USNMENT00671082–83 , USNMENT00671085–92 ), 1♂ 1♀ ( UVG USNMENT00671093–94 ), 1♂ 2♀ ( FSCA) ; same data except emerged 17 Mar 2008, 1f ( USNM USNMENT00104211 ) . MEXICO: Chiapas: San Cristobal de Las Casas , 7087 ft. [2161 m], 29 Jun 1969, 1♀ ( CNC USNMENT00215050 ) .

Etymology. This species is named for Gary Steck, one of the collectors of the type series.