Drosophila alabamensis Sturtevant 1918
Creators: name: Grimaldi, David A.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Drosophilidae
Drosophila
Drosophila alabamensis

description: Drosophila alabamensis Sturtevant, 1918a: 38.
DIAGNOSIS: Dark grayish-brown, pollinose fly with faint stripes on scutum; pleuron dark brown with diffuse, light, longitudinal stripe through middle; coloration not sexually dimorphic. Anterior reclinate seta lateral to slightly anterolateral to proclinate; cheek relatively deep (CD/ED 0.25); basal flagellomere without long setulae; wing long (ThL/WL 0.40), slightly dusky, with minute costal lappet at apex of Sc cell; abdomen mostly dark brown with some faint markings. Female: oviscapt heavily sclerotized, unique among North American species, with three posterodorsal pegs on peduncles. Male: hypandrium nearly square; aedeagus short, bulbous, scaled, sclerotized.
DESCRIPTION: Coloration: Little or no sexual dimorphism. Head mostly dull gray with some light areas; ocellar triangle and frontal vittae velvety black-brown, fronto-orbital plates slightly lighter, dull gray-brown; anterior edge of frons yellowish; cheek mostly light, with brown area around and above vibrissa; face dull yellow-brown; antennal pedicel and basal flagellomere light brown; clypeus and palps dark brown. Eyes brick red. Thorax dull gray-brown; scutum pollinose, with three complete, faint, lighter stripes (in line with dorsocentrals and in middle), pair of incomplete faint stripes just above notopleuron on posterior part of scutum; rim of scutellum slightly lighter than disk; postpronotal lobe dark yellowish; pleuron mostly dark brown, with diffuse, light, longitudinal stripe in middle running entire length of thorax. Wing slightly dusky, no markings except for small dark spot on veins at Sc break; halter light dusky brown, with darker spots on stem. Legs light dusky brown. Abdomen mostly dark brown, with lighter area on tergite 2 (in middle, triangular), and on anterolateral portions of tergites 4–6; small light patch on each of tergites 2–5 near lateral margin (decreasing in size caudad). Tergite 8 and proctiger in female slightly lighter.
Head: Frons, face, cheek, scape slightly pollinose. Antenna: Pedicel and scape setose; basal flagellomere with minute, light setulae; arista with relatively short branches, 4 dorsal, 1 ventral branch (midway between apical fork and last dorsal branch). Eye shape irregular in lateral view, interfacetal setulae dense and short. Face: slightly concave; carina low, narrow, on upper 2/3 of face. Vibrissa well differentiated, one pair, subvibrissal setae much smaller. Frons: Fronto-orbital plates slightly shiny. Fronto-orbital setae: proclinate approximately same length as posterior reclinate; anterior reclinate about 1/2 the size, directly lateral to slightly anterolateral to proclinate; posterior reclinate slightly closer to proclinate than to verticals. Ocellar seta between anterior and posterior ocelli, approximately same size as proclinate; postocellar setae convergent. Inner vertical seta slightly thicker and shorter than outer vertical. Palp flat, apex rounded; proboscis short, when retracted barely protruding beyond oral margin.
Head measurements (N = 4): CD/ED 0.25 (0.16–0.38), ED/EW 1.19 (1.02–1.28), FD/FW 0.99 (0.94–1.06), FL/LFW 0.88 (0.82–0.94), HW/ HD 1.46 (1.42–1.50), Ocellar S-index 1.22 (1.11– 1.40), OR1/OR3 0.88 (0.80–1.00), OR2/OR1 0.64 (0.63–0.66), VT-index 1.06 (1.04–1.09).
Thorax: Acrostichal setulae in 4–6 irregular rows; acrostichals anterior to dorsocentrals not enlarged. Anterior dorsocentral slightly shorter than posterior dorsocentral. Postpronotum with 2 setae; 3 long notopleural setae, forming triangle; 1 long, 1 short prealar; 1 long supraalar. Anterior scutellars parallel, posterior (apical) scutellars crossing at tips. Anterior katepisternal very short, 0.3× length of posterior katepisternal. Legs: Profemur with ventral row 4 long setae (lengths slightly greater than femur width), lateral row of 4 slightly shorter ones; male protarsus with setulae semi-erect. Mesotibia with ventroapical setae; metatibia with preapical dorsal seta. Wing: C just before Sc break slightly thickened and darkened, Sc break incised, forming minute lappet.
Thorax and wing measurements: 4-V index 2.33 (2.22–2.45), 5-X index 2.84 (2.61–2.93), C-index 2.22 (2.14–2.28), DC-index 0.66 (0.62– 0.71), hb-index 1.89 (1.76–2.13), S-index 0.49 (0.48–0.50), ThL 0.96 mm (0.93–1.01), ThL/WL 0.40 (0.39–0.43), WL/WW 2.19 (2.09–2.33).
Male Terminalia: Epandrium taller than wide, with microtrichia overall except ventral lobes; no setae dorsally (lateral surfaces only); ventral lobe of epandrium short, apex not reaching to level of surstylus apex, with lateral row 5–6 setae. Cercus less sclerotized than epandrium; not connected to epandrium; ventral margin flat, with fine setulae, no ventral lobe. Surstylus sclerotized, pendulous, without additional lobe; approximately 30 prensisetae (ca. 13 pegs, including dorsomedial row of 6 pegs, dorsolateral row of 5–6 pegs); thinner, longer prensisetae medially and at apex. Subepandrial sclerite heavily sclerotized, articulating laterally with bases of surstyli, curved in middle. Hypandrium nearly square, with slightly concave anterior margin; postgonites with microtrichia. Aedeagus short, stout, heavily sclerotized, scaled (mostly on lateral and dorsal surfaces). Aedeagal apodeme short, slightly shorter than aedeagus. Female Terminalia: Oviscapt heavily sclerotized, with row of 3 posterodorsal pegs on peduncles; row of apical 6 pegs forming flat, horizontal row beneath pedunculate pegs; row of ca. 6 minute pegs on ventral margin of oviscapt. Oviprovector scaled, but scales relatively small and sparse. Spermatheca heavily sclerotized, dome shaped, introvert extended about 3/4 into length of capsule.
TYPE: Holotype, female. USA: Alabama, Kushla, IV-9-15, A.H. Sturtevant, Ac. [accession] 5151, holotype, handwritten id label “ Drosophila alabamensis Sturtevant. ” In AMNH. Specimen is missing part of left wing and is somewhat shriveled; not dissected.
OTHER SPECIMENS EXAMINED: CANADA: Ontario: Algonquin Park, summer, 1956, D.D. Miller, 1♂ (dissected, no. 15) (AMNH). USA: Illinois: Carlinville, Marshall R. Wheeler, 9-5-52, 1♀ (AMNH), Aug. 23, 1954, 1♀, 1♂ (dissected, no. 17) (AMNH); Equality, IX /11/52 [no collector), 1♀, 1♂ (dissected, no. 16). Missouri: Lithium, Je 29, 1955, M.R. Wheeler, 2♀ (AMNH). Nebraska: 3 slides, labelled “ D. cinerea -? Nebraska [specific locality not given], male...MW [Marshall R. Wheeler],” one slide of the head, one of the genitalia, a third of the wing, all presumably of the same specimen. New York: Brainard, Rensselaer Co., July 11–22, 1966, P. & B. Wygodzinsky, 1♀ (AMNH). Texas: Austin, Oct. 14, 1950, M.R. Wheeler, 2086.12, 2♀ (AMNH); Oct. 25, 1950, M.R. Wheeler, 2♀ (1 dissected, no. 79), 1 ♂ (dissected, no. 18) (AMNH); 21 Nov. 1953 M.R. Wheeler, 1♀ (AMNH). Virginia: Montgomery Co., IV/15 /52, M. Levitan, 1♀ (AMNH).
COMMENTS: Male genitalia of the slidemounted Nebraska specimen unmistakably show the specimen is H. alabamensis. Also, see comments under H. cinerea.
description: Published as part of Grimaldi, David A., 2018, Hirtodrosophila Of North America (Diptera: Drosophilidae), pp. 1 in Bulletin of the American Museum of Natural History 2018 (421) on page 1, DOI: 10.1206/0003-0090-421.1.1, http://zenodo.org/record/10687866