Body length: 2.5–4.0 mm [male], 2.7–5.0 mm [female]. Cream-white with yellowish-brown suffusion; eyes contiguous in male, frons broader than ocellar tubercle in female; antennal flagellum approximately twice length of scape and pedicel combined, attenuate and pyriform, notched apically; scutum light brown to dark grey, with cream-white to yellow patches marginally (pale area often more extensive in female); entire thorax overlain with glaucous pubescence; wing vein M1 meeting vein R5, forming closed petiolate cell r5; R4 branching from R5 along basal half of cell r5; abdomen with tergites either dark brown-grey with pale white to yellow band posteriorly, or vivid white with orange-brown suffusion laterally (and medially in female); tergite 2 sensory setae well defined (Fig. 1); male epandrium split medially as two sclerites, halves sub-quadrangular with posterior margins flared or tapered laterally, or large and globose; epandrium not completely covering gonocoxite ventrally; gonocoxite and aedeagus extended anteriorly from anterior margin of epandrium a relatively short distance; gonocoxite irregular, largely reduced, with strongly sclerotized dorsal process; gonocoxal apodeme relatively thickened; hypandrium as paired lobes, size and shape variable, with margin of setae, but no large setal brushes; lateral aedeagal bulb present; distiphallus bifid, recurved dorsally at base or straight, slender or slightly thickened, arms parallel or divergent. Female sternite 8 longer than tergite 8, almost level with cerci, broadly rounded or weakly emarginate (not forming distinct lobes posterolaterally); 6–7 acanthophorite spines present on lobes of well defined tergite 9+10; furca ring-like, dark-sclerotized; spermathecae paired, sclerotized and irregular-shaped; spermathecal sac simple, minute, elongate.

Heteromphrale is closely related to Brevitrichia, a genus found primarily in western North America and throughout Central America (Kelsey 1969; Woodley 2009). Heteromphrale can be differentiated from Brevitrichia by the shape of sternite 8 in the female (apically emarginate with rounded posterolateral lobes in Brevitrichia), male distiphallus short and thick (relatively long and thread-like in Brevitrichia) and the distiphallus straight (highly reflexed basally in Brevitrichia). The distiphallus of Brevitrichia can be greatly elongated, with the basiphallus reflexed upon itself up to 180° as found in the proratine genus Cyrtosathe Winterton & Metz, 2005 (Winterton and Metz 2005). This complex arrangement of the distiphallus in Brevitrichia often projects anteriorly into the abdominal cavity and is supported by aedeagal guides formed by paired, blade-like extensions of the hypoproct; the aedeagus is largely contained within the genitalic capsule in Heteromphrale, with hypoproct extensions absent. The distinct dorsal processes (physically ventral) on the gonocoxites of Heteromphrale (Figs 2–3) are similar to those found in some species of Propebrevitrichia Kelsey, 1969 (see Winterton 2005) and indicate a likely close relationship between these genera.

Southern South America; recorded from Uruguay, Chile and Argentina.

Heteromphrale blanca sp. n., Heteromphrale chilensis (Kröber) and Heteromphrale cyanops (Edwards).

Holotype male, “ARGENTINA. La Rioja Prov., Departamento Famatina, 12 km N Pituil, 4, 135 ft; 20-X-1997, M.E. Irwin, F.D. Parker, S. Roig, malaise, -28°30'54.36, -67°20'20.04” / “Schlinger Foundation Argentina Expedition, November 1997, ME Irwin, F.D. Parker & S. Roig” / “HOLOTYPUS ♂ Heteromphrale blanca Winterton & Gaimari” [red label]. (MEI165196) (CASC, point mounted, excellent condition).

ARGENTINA: La Rioja Province: Departamento Famatina, 12 km N Pituil, 4135 ft. [1260 m], -28°30'54.36, -67°20'20.04, 15.X.1997, M.E. Irwin, F.D. Parker & S. Roig, ex. Malaise trap [1 male (CASC)] (MEI165195); 2 females (CASC) (MEI165197, 165198)]; on leaves of Prosopis tree [1 male (CSCA)]; 53 km from Villa Unión, Route 40, Pedregosa River, 27.XI.1976, ex. sweeping Prosopis chilensis [1 female (USNM)]; Departamento Famatina, 12 km N Pituil, 4135 ft. [1260 m], -28°30'54.36, -67°20'20.04, 15.X.1997, M.E. Irwin, F.D. Parker & S. Roig, ex. Malaise trap [1 male (DEI)] (MEI165199); Tucuman Province: 8 km NW Amaichá del Valle, 1847 m, -26°32.35', -65°58.37', 22–25.X.2003, M.E. Irwin & F.D. Parker, ex. Malaise trap in ravine [1 male (CSCA); 1 male (USNM)]. Salta Province: 10 km S Cafayete, 26.X–13.XI.2003, M.E. Irwin, F.D. Parker, -26.1514°, -65.9586°, 1644 m, Malaise in Prosopis covered dunes [1 female (CSCA)] (MEI165204).

Antennal flagellum dark brown to black, conical and evenly tapered distally; mouthparts normal, nearly filling oral cavity; scutum without glabrous dorsocentral patches; wing with vein R4 diverging from vein R5 at point between one-quarter and one-half of cell r5; abdomen dark with pale posterior band on tergites 2–5; tergite 2 sensory patch distinct as two small patches; male epandrium not bulbous, dense fringe of white setae along posterior margin; hypandrium lobes relatively large and sub-triangular; distiphallus with arms parallel; lateral aedeagal bulbs relatively large; female sternite 8 posterior edge rounded; acanthophorite spines elongate and finely tapered, wispy.

Body length: 2.5–4.0 mm [male], 2.7–4.2 mm [female]. Head (Figs 4A–B, 5A–B). Frons, parafacial, face and gena cream-white to yellow; female frons with tan suffusion dorsomedially and surface slightly furrowed medially, sparsely distributed with small, pale setae; male frons with whitish pubescence and dark where eyes are proximate; occiput with yellow suffusion marginally, black medially; face white; flagellum brown to black; scape pale yellow; pedicel yellowish-tan with a few minute pale setae; mouthparts normal-sized, nearly filling oral cavity; pale yellow, including prementum, labellum, labellar setae, and small cylindrical palpus. Thorax (Figs 5A–B, 6). Scutum black to grey, small pale yellow areas marginally (postpronotal lobe, notopleuron and supra-alar area), more extensive in female and additionally with yellow on anterior part of scutum adjacent to postpronotum, on postalar callus, and medially on posterior part of scutum; entire thorax overlain with dense glaucous pubescence; scutellum dark medially, yellow marginally (yellow area more extensive in female); scutum without pale setae, some present on postpronotal lobe, anepisternum and katepisternum; prosternum yellow; proepisternum and proepimeron yellow, sometimes with brown on posterior part; anepisternum grey pubescent, yellow in upper part; katepisternum grey pubescent, yellow in posterodorsal corner (in female, along most of dorsal margin); anepimeron grey pubescent anteriorly, yellow posteriorly; meron grey pubescent, except yellow dorsally; coxae light brown to orange; legs tan to dark yellow-orange; distal tarsomeres darker than rest of leg; haltere stem brown, knob white with brown suffusion dorsally; wing venation pale yellow; vein R4 diverging from R5 at point between one-quarter and one-half of cell r5. Abdomen (Fig. 6). Segments dark brown-grey with pale white-yellow band posteriorly; sternites dark brown-grey; sparse pale setae on most segments; tergite 2 sensory patch large and distinct, divided medially into two small patches, patch concolorous with rest of tergite. Male genitalia (Figs 2A–B, 10A). Epandrium sub-quadrangular, outer margins tapered, dark brown in basal half and pale yellow in distal half, white setal fringe along margin; hypandrium lobes relatively large, triangular; gonocoxite with darkly sclerotized, narrowly acuminate, dorsal process; gonostylus complex, apparently fused to gonocoxites, with posteriorly directed margin fringed with setae, and hook-like process dorsally, inner lobe triangular and fused medially; gonocoxal apodeme broadly flattened, curved medially; ejaculatory apodeme relatively elongate, directed anteriorly; lateral aedeagal bulbs large, round; distiphallus elongate, arms proximate and parallel, broadly curved ventrally at base then straight along distal length. Female genitalia (Fig. 9A–C). Sternite 8 with posterior edge rounded, with posterolateral part fringed with long wispy setae; acanthophorite spines elongate and curved, becoming wispy and hair-like.

Heteromphrale blanca sp. n. is very similar to Heteromphrale cyanops in overall body color, but differs considerably in male genitalic morphology and in the shape of the female sternite 8. As in Heteromphrale chilensis, the tergite 2 sensory patch is large and distinct, and is divided into two small patches with the setae directed medially. In males, the non-bulbous epandrium distinguishes this species and Heteromphrale chilensis from Heteromphrale cyanops, but the dense fringe of white setae along the posterior margin, distinguishes Heteromphrale blanca sp. n. from Heteromphrale chilensis. In females, the rounded sternite 8 distinguishes Heteromphrale blanca sp. n. from Heteromphrale cyanops, and the fringe of long wispy setae and elongate wispy acanthophorite spines distinguishes this species from Heteromphrale cyanops and Heteromphrale chilensis.

Known only from Argentina (La Rioja, Salta and Tucuman Provinces).

The specific epithet is a Latin adjective – blanca – meaning white, referring to the dense fringe of white setae along the posterior margin of the epandrium.

Holotype female, label data: “CHILE Concepción, P. Herbst” / “coll. Lichtwardt” / “Pseudatrichia chilensis det. Kröber” / “HOLOTYPUS”. (DEI) (micropinmounted, reasonable condition except abdomen greasy and antennae missing).

CHILE: Elqui Province: 10 km N La Serena, 10 m, -29°49.27', -71°16.20', 8.X.2003, M.E. Irwin, ex. hand net in coastal dunes [3 males (CASC) (MEI165208, 165209, 165210), 1 female (CASC) (MEI165211), 3 males (CSCA) (MEI165206, 165207 165212)].

Antennal flagellum orange brown, abruptly pear-shaped; female frons with extensive pile; mouthparts much smaller than oral cavity; scutum with glabrous, glossy dorsocentral spot (linear in female); wing with vein R4 diverging from R5 at point in basal quarter of cell r5; abdomen vivid matte-white with brown suffusion laterally (also medially in female), and with dark brown spot encompassing tergite 2 sensory patch; tergite 2 sensory patch distinct as two small patches; male epandrium not bulbous, without dense fringe of setae; hypandrium lobes sub-triangular with sclerotized lateral margins; distiphallus arms divergent; lateral aedeagal bulbs relatively small; female sternite 8 rounded posteriorly, without fringing elongate setae; acanthophorite spines robust and stout.

Body length: 2.6–3.2 mm [male], 4.8 mm [female]. Head (Figs 4C–D, 5C–D). Frons cream-white, female frons with yellow to light brown patch dorsomedially, sometimes more extensive brown-orange suffusion, surface wrinkled, sparsely distributed with small, pale setae; parafacial in male dark orange medially, white along eye margin (in female entirely yellow); ocellar triangle grey pubescent, raised, with anterior ocellus slightly larger than posterior ocellus; occiput and postgena dark with pale yellow with orange-brown suffusion marginally; face white with brown suffusion; mouthparts pale, relatively small in size, much smaller than oral cavity; pale yellow, including labellum, labellar setae, and small cylindrical palpus; prementum in male dark orange (in female pale yellow); flagellum orange-brown, abruptly pyriform, tapered distally; scape and pedicel brown with a few minute pale setae. Thorax (Figs 5C–D, 7). Scutum light brown to grey, yellow on postpronotal lobe, anterior part of scutum adjacent to postpronotum, notopleuron, supra-alar area and postalar callus (in female, with yellow more extensive in these areas); entire thorax overlain with dense glaucous pubescence; glossy black dorsocentral patches present at point posterior third of scutum, patches round in male, elongate in female, paired median brown vittae in anterior half; scutellum dark medially, pale marginally; prosternum yellow, bare; proepisternum and proepimeron orange (in female yellow); anepisternum orange in dorsal half and along posterior margin (in female yellow), except white along dorsal margin and grey to brown pubescent anteroventrally; katepisternum grey to brown pubescent, except orange in upper part (in female yellow); anepimeron white to yellow, darkened anteriorly; meron shining glossy brown, except white pubescent dorsally; legs pale cream with uniform or mottled brown suffusion, tibiae orange, with dorsal surface pale; hind tibia becoming darker distally; tarsi dark. Wing. Venation pale brown; vein R4 diverging from R5 at point in basal quarter of cell r5; aberrant specimens with either spurious vein present between distal part of R5 and C (Fig. 7B) or R4 incomplete basally; haltere mostly cream-white. Abdomen (Fig. 7). Vivid matte-white to cream with brown suffusion laterally; dark brown band posteriorly (more obvious in female), tergite 2 with dark brown band level with and encompassing sensory setal patch; sternites white with brown suffusion laterally; sparse elongate setae on most segments. Male genitalia (Figs 2C–D, 10B). Epandrium brown basally and pale yellow marginally; sub-quadrangular with posterior margins tapered, fine setae along margin; hypandrium halves small, sub-triangular with multiple lobes directed posteromedially, dark sclerotized along anterior and lateral margins; gonocoxite with darkly sclerotized, acuminate, dorsal process; gonostylus large, posteriorly directed and united medially, apparently fused to gonocoxites; gonocoxal apodeme broadly flattened, outer margin curved, inner margin straight; ejaculatory apodeme minute, directed ventrally; lateral aedeagal bulbs small; ventral apodeme dark sclerotized; distiphallus divergent laterally around gonostylus, medially directed process from between distiphallus projecting towards hypoproct, curved anteriorly, apex spatulate. Female genitalia (Figs 9C–E). Sternite 8 with posterior edge rounded, with longish setae around fringe; acanthophorite spines long and robust.

Originally described in Pseudatrichia, Kröber (1937) later erected Heteromphrale to accommodate this species. Although the female holotype is faded, encrusted with naphthalene and dust, and the abdomen is greasy, the distinctive bone-white color of the abdomen is still observable, along with the brown coloration around the tergite 2 sensory patch. In the original description, Kröber (1928) described the flagellum as red-yellowish color, but the antennae are now lost from the type specimen.

Heteromphrale chilensis is easily distinguished from other species of Heteromphrale by the glabrous dorsocentral patches on the scutum (elongate in females), mostly bone-white coloured abdomen, basally bulbous antennal first flagellomere, and the relatively tiny mouthparts. As in Heteromphrale blanca sp. n., the tergite 2 sensory patch is large and distinct, and is divided into two small patches with the setae directed medially, and the epandrium is not bulbous as in Heteromphrale cyanops, but in Heteromphrale chilensis there is no dense fringe of long white setae. Also like Heteromphrale blanca sp. n., the female sternite 8 is rounded, but in Heteromphrale chilensis, the edge is not fringed with long wispy setae, and the acanthophorite spines are robust.

Known from Chile (Biobío Region (Concepcíon Province) and Coquimbo Region (Elqui Province)).

Holotype male, URUGUAY: Montevideo, 21.i.1927, F. & M. Edwards (MEI165200). (BMNH) (excellent condition).

ARGENTINA: Catamarca Province: 50 km W Andalgala, 31.X.1972, G.E. Bohart [1 male (UCDC)]; Andalgala, 4.XI.1972, G.E. Bohart, Prosopis alba [1 male (UCDC)]; 28 km SE Tinogasta, 1100 m, -28.2450°, -67.4557°, 17.X.1997, M.E. Irwin, F.D. Parker & S. Roig, ex. inland dunes [4 males (CSCA)]. La Rioja Province: Departamento Famatina, 12 km N Pituil, 4135 ft. [1260 m], -28°30'54.36, -67°20'20.04, 15.X.1997, M.E. Irwin, F.D. Parker & S. Roig, ex. Malaise trap [1 female (CASC), 1 female (CSCA)], ex. leaves of Prosopis tree [1 male (CASC)], 20.X.1997, ex. leaves of Prosopis tree [1 female (CASC)]. 16 km NE Pagancillo, Route 18, 28.XI.1976, ex. sweeping Prosopis chilensis [2 males (USNM)]. Mendoza Province: Departmento de Levalle, 20 km N Parque Telteca, -32.2916°, -67.3878°, 10.x.1997, M.E. Irwin, F.D. Parker, S. Roig, ex. Cerecidium blooms in sandy area [1 male (CASC)]. Salta Province: 10 km S Cafayete, 1644 m, -26°09.05', -65°57.31', 22–26.X.2003, M.E. Irwin & F.D. Parker, ex. Malaise trap in Prosopis-covered dunes [1 female (CASC), 1 female (CSCA)]. Tucuman Province: 8 km NW Amaichá del Valle, 1847 m, -26°32.35', -65°58.37', 22–25.X.2003, M.E. Irwin & F.D. Parker, ex. Malaise trap in ravine [1 female (CASC)].

Antennal flagellum brown, conical and evenly tapered distally; mouthparts normal, nearly filling oral cavity; scutum without glabrous dorsocentral patches; wing with vein R4 diverging from vein R5 at point in basal quarter of cell r5; abdomen dark with pale posterior band on tergites 2–5; tergite 2 sensory patch relatively small, as single narrowed patch; male epandrium relatively large and bulbous, without distinctive white setal fringe along posterior margin; hypandrium small, lobes irregular; distiphallus arms parallel; lateral aedeagal bulb relatively large; female sternite 8 shallowly emarginate posteriorly, without fringing elongate setae; acanthophorite spines short and stout.

Body length: 2.5–3.5 mm [male], 3.0–4.0 mm [female]. Head (Figs 4E–F, 5E–F). Frons, parafacial, face and gena cream-white to yellow (in female, with tan suffusion on frons, with median furrow), sparsely distributed with small, pale setae; ocellar triangle grey pubescent, slightly raised, with anterior ocellus slightly larger than posterior ocellus occiput and postgena dark, pale marginally with yellow suffusion; face white; mouthparts pale yellow, including labellum, labellar setae, and small cylindrical palpus; prementum pale yellow to slightly darker yellow; antennae with flagellum brown, evenly tapered; scape and pedicel pale brown-orange with a few minute pale setae. Thorax (Figs 5E–F, 8). Scutum black to grey, cream-white to yellow areas on postpronotal lobe, anterior part of scutum adjacent to postpronotum, notopleuron, supra-alar area and postalar callus with slightly darker, thin, median stripe (more extensive in female in these areas, and additionally with yellow medially on posterior part of scutum, and a slight medial brownish mark extending from scutellum); thorax mostly overlain with dense glaucous pubescence; scutum largely without setae, some present on postpronotal lobe, anepisternum and katepisternum; scutellum dark medially, pale marginally; prosternum yellow, bare; proepisternum and proepimeron yellow, sometimes slightly darker on posterior part; anepisternum yellow in dorsal half and along posterior margin, grey pubescent anteroventrally; katepisternum grey pubescent, except yellow along entire dorsal margin; anepimeron yellow, usually with some grey pubescence anteriorly; meron grey pubescent, except yellow dorsally; coxae light brown; legs pale cream with uniform brown suffusion; basitarsi orange with slightly darker distal tip, and remaining tarsomeres dark orange. Wing. Venation pale yellow; vein R4 diverging from R5 at point in basal quarter of r5; haltere with stem mostly brown, distal part of stem and entire knob white. Abdomen (Fig. 8). Tergites dark brown pubescence with pale white band posteriorly; with pale setae, longer laterally; tergite 2 sensory patch small and inconspicuous, as single small, brown narrow patch, completely encompassed within dark brown pubescence; sternites white posteriorly, dark brown anteriorly and laterally; with sparse short pale setae. Male genitalia (Figs  3, 10C). Epandrium robust, globose, dark orange, with sparse, small white setae; hypandrium lobes small, membranous, sub-triangular, each with two lobes directed posteromedially; gonocoxite with large, darkly sclerotized, anvil-like dorsal process; gonostylus complex, apparently fused to gonocoxites, outer lobe L-shaped with posteriorly directed margin fringed with setae, inner lobe triangular and fused medially; gonocoxal apodeme broadly flattened, and curved medially; ejaculatory apodeme relatively elongate, directed anteriorly; lateral aedeagal bulbs large; ventral apodeme dark sclerotized; distiphallus parallel, ventrally directed towards apex. Female genitalia (Fig. 9G–I). Sternite 8 with posterior edge weakly emarginate, margin thin; acanthophorite spines stout.

Heteromphrale cyanops was originally described in the genus Pseudomphrale by Edwards (1932) based on a single male specimen from Uruguay. Edwards (1932) noted that the specimen was taken in a sandy spot near the shore, and also noted that the eye in life was deep blue in color; this eye color is retained in some specimens. Kelsey (1969) subsequently transferred the species to Heteromphrale. Heteromphrale cyanops is very similar to Heteromphrale blanca sp. n. in overall body coloration, but is easily distinguished from both other species of Heteromphrale by the greatly enlarged, bulbous epandrium in the male, the shallowly emarginate posterior edge of sternite 8 in the female, and by the tergite 2 sensory patch being a relatively small, singular, narrowed patch.

Known from Argentina (Catamarca, La Rioja, Mendoza, Salta and Tucuman Provinces) and Uruguay (Montevideo Department).