Paraclius problematicus ( Parent, 1930 ) Soares & Capellari & Ale-Rocha, 2023

Soares, Matheus M. M., Capellari, Renato S. & Ale-Rocha, Rosaly, 2023, New or little-known Neotropical Dolichopodidae (Diptera) (II): genus Hercostomus Loew excluded from the Neotropics, Zootaxa 5254 (2), pp. 181-208 : 185-190

Paraclius problematicus ( Parent, 1930) comb. nov.

( Figs 2–5 , 15 )

Hercostomus problematicus Parent, 1930: 14 , figs 13–14. Type locality: Belém , Pará, Brazil.

Sarcionus maculipennis Van Duzee, 1934: 373 , figs 9–10. Type locality: Kartabo, Cuyuni-Mazaruni, Guyana. Transferred to Cheiromyia by Brooks (2005: 43) and to Paraclius by Brooks et al. (2010: 55). Syn. nov.

Diagnosis (male). Face very narrow at mid-length (narrower than mid ocellus) ( Figs 2C , 3B , 5B ); postpedicel subtriangular, brownish, except basal 1/3 reddish yellow ( Figs 2A, C , 3A ). Legs mostly yellow, except lateral surface of coxae II and III brownish; tarsus II and III dark brown from apical 2/3 of tarsomere 2 ( Figs 2A , 3A ); tarsus I and III unmodified; tarsus II with apical 1/3 of IIt 2 and entire IIt 3 laterally compressed, IIt 4 with apicoventral projection overlapping the base of IIt 5, apical 1/3 of IIt 2 to base of IIt 4 covered by whitish pollinosity anteriorly ( Fig. 3C , 5C ). Wing membrane hyaline to slightly infuscate, with apical 1/3 brownish, M 1 gradually curved towards R 4+5 ( Fig. 3D , 5D ).

Redescription. Male (based on identified specimens and photographs of holotype) ( Figs 2 , 3 ). Body length: 4.8–5.5 mm. Wing length: 3.9–4.4 mm (n = 10). Head ( Figs 2C , 3B , 5B ). Upper-most 6–8 and single lower-most postocular setae black, remaining setae white. Frons subrectangular (about 1.5X wider than high), black, covered by weak silvery pruinosity. Face ground color yellow, but obscured by dense silvery pruinosity, narrowing in middle (narrower than mid ocellus at narrowest point, MSSC). Clypeus subtriangular (1.5X longer than wide), about 1/3 of face height, lower margin rounded, ending well above lower eye margin. Palpus pale brown, covered by weak yellowish gray pruinosity and a few small black setae, 1 stronger seta at apex. Proboscis brown, labellum with long, slender setae, prementum with one group of short, slender setae. Pair of divergent strong ocellar setae and 2 pairs of tiny postocellar setae; pair of strong, slightly convergent vertical setae, pair of short paravertical setae, about 1/3 of length of vertical seta. Postcranium black, covered by weak silvery pruinosity. Antenna with scape, pedicel and basal 1/3 of postpedicel reddish yellow, apical 2/3 of postpedicel brownish; scape with short setae on dorsal surface and 3–4 long setae at apex, with acute anterior and ventral processes at apex; pedicel short, with crown of setae at apex; postpedicel 1.5X longer than wide, subtriangular, with short whitish pubescence; arista-like stylus blackish, dorsal, arising from upper edge at basal half of postpedicel, as long as eye height, two-segmented, first segment short, ending at apex of postpedicel and covered by short pubescence, second segment long, about 3.5X longer than first segment, covered by short microtrichia. Thorax ( Figs 2A , 3A , 5A ). Mesonotum mostly metallic dark green, with weak bluish reflections, notopleuron covered by dense silvery pruinosity, postpronotal lobe and postalar callus yellowish brown. Scutellum concolorous with mesonotum. Pleura gray, covered by weak silvery pruinosity. Chaetotaxy: pronotum with row of black setae; acrostichals short, biseriate, ending at fourth dorsocentral seta; 6 pairs of dorsocentral (anterior pair greatly reduced, about 1/2 of length of second pair); 1 pre-, 1 sutural and 1 postsutural intra-alars; 1 strong and 2 short postpronotals; 2 strong supra-alars, 1 positioned between postpronotal lobe and notopleuron and 1 close to postalar callus; 1 strong postalar; 2 strong notopleurals; one cluster of fine white setulae on upper surface of proepisternum, and row of more conspicuous black setulae in front of anterior spiracle; lower surface of proepisternum with 1 strong seta directed anteroventrally and cluster of fine white setulae; metepisternum with row of fine white setulae; scutellum with pair of strong medial scutellars and pair of smaller setae laterad, about 1/4 as long as medial scutellars. Wing ( Figs 3D , 5D ). Membrane hyaline to slightly infuscate, with apical 1/3 brownish. Costa ending at M 1 before wing apex; R 1 ending at basal 3/8 of wing; R 2+3 and R 4+5 nearly straight; M 1 gently curved towards R 4+5; M 4 not reaching wing margin; cell dm ending at apical 5/8 of wing; length of crossvein dm-m/last part of M 4 (“CuAx ratio”): 1.3; CuA+CuP present as sinuous fold in membrane, not reaching wing margin. Lower calypter yellow with blackish cilia; halter yellow. Legs ( Figs 2A , 3A, C , 5C ). Mostly yellow; lateral surface of coxae II and III brownish; tarsus II and III dark brown from apical 2/3 of tarsomere 2 onwards; setae on legs black, unless otherwise mentioned. Leg I. Podomere ratios: 52, 45, 22/10/6/4/3. Anterior surface of coxa I covered by short setae and weak silvery pruinosity, outer edge with 2 strong setae, 1 near middle and 1 near apex, apical edge with 2 strong setae. Femur I covered by short vestiture of setae, except extreme base and larger part of ventral surface bare, with 1 short posteroventral preapical seta. Tibia I with 3 short dorsal setae at 2/8, 4/8 and 7/8, 1 anterodorsal seta at 2/8, 1 posterodorsal seta at 7/8 and posterior row of fine setae increasing in size at apical 1/3 (MSSC). It 1 with 1 short basiventral seta, It 2–5 unmodified. Leg II. Podomere ratios: 66, 70, 35/25/16/8/5. Anterior surface of coxa II covered by short setae and weak silvery pruinosity, outer edge with 2 strong setae near middle, inner and apical edges with row of slender setae. Trochanter II with 1 anterior seta at apex and 1 ventral pale seta at middle. Femur II covered by short vestiture of setae, except ventral surface bare, 1 strong anterodorsal preapical seta at 7/8, 1 short posteroventral preapical seta and anteroventral row of fine white setulae from base to apical 5/8 (MSSC). Tibia II with 4 conspicuous anterodorsal setae at 1.5/8, 2.5/8, 4/8 and 7.5/8 (about 1/3 of length of preceding seta) and 1 anterior seta at 7.5/8; 4 posterodorsal setae at 1/8 (about half length of second seta), 2/8, 5/8 and 7.5/8, 1 ventral seta at 4/8 and 1 anteroventral seta and 1 fine long posteroventral seta at apex. Tarsus II ( Fig. 3C , 5C ): IIt 1 with 1 long basiventral seta, apical 1/3 of IIt 2 and IIt 3 laterally compressed, IIt 4 with ventral apical projection overlapping base of IIt 5, apical 1/3 of IIt 2 and entire IIt 3 covered by whitish pubescence anteriorly (all MSSC). Leg III. Podomere ratios: 69, 87, 26/39/21/10/4. Anterior surface of coxa III with 2 long setae at apical edge, lateral edge with 1 long seta at middle and 1 short seta at apex. Femur III laterally compressed, about 2X wider than femur II at broadest point, covered by short vestiture of setae, except ventral surface mostly bare, with 1 strong anterodorsal at apical 6/8, 1 antero- and 1 posteroventral short seta at apex, anteroventral and ventral rows of fine white setulae from base to basal 4/8. Tibia III with pairs of antero- and posterodorsal setae at 1/8 (about half length of second pair), 1.5/8, and 3/8, 2 anterodorsal setae at 5/8 and 7.5/8, 2 posterodorsal setae, at 4/8 and 7/8, 2 ventral setae, 5.5/8 and apex, and row of short, erect setae from basal 1.5/8 to apical 5/8. Tarsus III: IIIt 1 with 1 short basiventral seta and 1 short ventral seta near middle. IIIt 2–5 unmodified. Abdomen ( Figs 2A, D , 3A ). Mostly dark brown (without metallic reflections), tergites 1–5 with lateral patches of silvery pruinosity. Tergites 1–5 covered by short black setae, posterior margins with longer black setae, tergites 6 and 7 bare. Segment 7 forming well sclerotized but short peduncle, longer than tergite 6. Sternite 8 drop-shaped, covered by short black setae, increasing in length at posterior margin. Hypopygium ( Fig. 4 ). Shorter than abdomen; epandrium dark brown, subrectangular, truncated at apex, twice longer than high at highest point, with 1 minute basiventral seta ( Fig. 4A, B ); apicoventral epandrial lobe shorter than surstyli, digitiform in lateral view ( Fig. 4A, B ) and C-shaped in ventral view ( Fig. 4C ), with two long and slender apical setae at outer edge; ventral lobe of surstylus long and narrow, curved dorsally at apex, with 1 long and wide seta ventrally, and 1 long and slender seta at basal 1/3 of dorsal edge ( Fig. 4F ); dorsal lobe of surstylus with narrow apical projection and short digitiform dorsal projection at middle and weakly sclerotized at apex, 1 short ventral seta near apex ( Fig. 4G ); postgonite as long as ventral lobe of surstylus, well sclerotized and weakly curved ventrally at apex ( Fig. 4E ); proctiger slender, shorter than postgonite ( Fig. 4E ); basal sclerite of sperm pump narrow, positioned dorsally to sperm pump ( Fig. 4E ); sperm pump long and strongly folded back over itself, but not spherical, slightly longer than epandrium length ( Fig. 4B, E ); ejaculatory apodeme short, about 1/4 as long as sperm pump, weakly sclerotized and somewhat fan-shaped ( Fig. 4E ); hypandrium laterally forked into two branches, each narrowing and membranous at apex ( Fig. 4E ); phallus tubular, bifurcate and narrowing at apex ( Fig. 4B, E ); cercus subtriangular, about half-length of epandrium, yellow with ventral margin broadly dark, covered by small erect yellowish setae and 1 long apical seta ( Fig. 4A, D ). Female (based on the original description, none confidently associated with males). Similar to male, except for MSSC; wing with apical darkening spot less pronounced, although visible.

Examined type material. Hercostomus problematicus : HOLOTYPE ♁ (based on photographs) ( Fig.2 )labelled as: “[ Brazil], Pará, Belem [ca 1°25′21.9″S 48°25′31.6″W] | 11.-26. V.27. Zerny”; “Type” [red label]; “ Hercostomus | problematicus | Type | O. Parent ” [handwritten] ( NHMW).

Sarcionus maculipennis : HOLOTYPE ♁ (based on photographs) ( Fig. 5 ) labelled as: “Kartabo [ca 6°24′13.2″N 58°37′27.1″W] | Bartica District [Cuyuni-Mazaruni] | British Guiana [ Guyana] | 1921”; “ Sarcionus | maculipennis [handwritten] | Holotype. Van Duzee” ( AMNH).

Additional examined material. BRAZIL, Amazonas, Km 31 Embrapa [ca 2°53′37.2″S 59°58′23.4″W], 26.xii.1991, L.P. Albuquerque, J. Binda, Arm. Shannon, C. Cacau [Shannon trap with Theobroma cacao bait], Isc. Fruta [fruit bait], 26.xii.1991 (12 ♁, INPA) ; idem, 04.vii.1991 (1 ♁, INPA) ; idem, 26.iv.1991 (1 ♁, INPA) ; idem, 12.xii.1991 (9 ♁, INPA) ; idem, 18.xii.1991 (2 ♁, INPA) ; idem, 8.i.1992 (6 ♁, INPA, 1 dissected) ; idem, 15.i.1992 (15 ♁, INPA, 1 dissected) ; idem, 22.i.1992 (3 ♁, INPA) ; idem, Arm. Shannon, C. Andiroba [Shannon trap with Carapa guianensis bait] (1 ♁, INPA) ; idem, 19.ii.1992, Arm. Shannon, C. Cacau (4 ♁, INPA) ; idem, 26.ii.1992 (1 ♁, INPA) ; idem, 29.i.1992 (4 ♁, INPA) ; idem, 6.ii.1992 (3 ♁, INPA) ; idem, 4.vi.1992 (2 ♁, INPA) ; idem, 11.iii.1992 (2 ♁, INPA) ; idem, 20.v.1992 (1 ♁, INPA) ; idem, 15.v.1992 (4 ♁, INPA) ; Manaus, R.F. Adolpho Ducke [ca 2°57′06.5″S 59°55′28.3″W], 19–23.iii.2001, Isca de Fruta , R. Ale-Rocha, J.F. Vidal, A.P. Marques cols. (1 ♁, INPA) ; Rio Nhamundá , 01°35′11″S 57°37′32″W, 25m, 17–20.v.2008, J.A. Rafael e equipe, Arm suspensa lâmina d’água (2 ♁, INPA) . Amapá, Amapari [ca 0°57′49.9″N 51°59′58.6″W], Tucano-2, 6–7.xi.1993, N. Bittencourt, Armadilha Suspensa 1.6 m (1 ♁, MPEG) ; idem, 11–15.xi.1993 (1 ♁, MPEG) ; Oiapoque , BR 156 km 25, 3°39′35″N 51°46′17″W, iii–vii.2020, Malaise, floresta, J.A. Rafael, S.P. Lima & F.F. Xavier Fº (3 ♁, INPA) . Pará, Belém, Mocambo [ca 1°25′21.9″S 48°25′31.6″W], Arm. Malaise, 05.xii.1977 (1 ♁, MPEG) .

Distribution. Brazil (state of Pará and newly recorded from states of Amapá and Amazonas) and Guyana (new country record) ( Fig. 15 ). Widely distributed in Amazonian lowlands.

Remarks. Paraclius problematicus comb. nov. is easily recognized by the male face very narrow at middle, narrower than mid ocellus, wing hyaline to slightly infuscate, with apical 1/3 brownish and IIt 2–3 laterally compressed. After the examination of photographs of the male holotype of Sarcionus maculipennis Van Duzee, 1934 housed at AMNH ( Fig. 5 ) and illustrations of the male terminalia provided by Scott Brooks (CNC), we concluded that S. maculipennis is conspecific and should be synonymized under P. problematicus comb. nov. The male hypopygium has an enlarged sperm pump similar to that found in species of Cheiromyia Dyte which was assumed to be synapomorphic for the genus plus Sarcionus maculipennis Van Duzee ( Brooks 2005, character 51: 1, fig. 8C). For the time being, we agree with Brooks et al. (2010, 2018), who transferred the species to Paraclius , leaving in Cheiromyia only the species with antler-like male postpedicel and apicoventral epandrial lobe large. The different conditions seen in the sperm pump are treated below under the Discussion section.

It is noteworthy that all Brazilian specimens from the Amazonas state were exclusively males, collected in relatively large numbers using fruit baits and Shannon traps.

Figures

FIGURE 2. Paraclius problematicus (Parent) comb. nov., male holotype (NHMW). A. Habitus, lateral view; B. labels; C. Head, anterior view; D. Abdomen and hypopygium, lateral view. Original images lacked scale bars. Photographs by Ģnther Ŵss, NHMW.

FIGURE 3. Paraclius problematicus (Parent) comb. nov., identified male specimen from Amazonas state. A. Habitus, lateral view; B. Head, anterior view; C. Tarsus II, anterior view; D. Left wing. Abbreviations: CuA+CuP anterior branch of cubital vein + posterior branch of cubital vein; dm-m = discal medial crossvein; IIt 2 = mid tarsomere 2; IIt 3 = mid tarsomere 3; M 1 = first branch of media; M 4 = fourth branch of media; R 1 = anterior branch of radius; R 2+3 = second branch of radius; R = third 4+5 branch of radius.

FIGURE 4. Paraclius problematicus (Parent) comb. nov., hypopygium, identified specimen from Amazonas state. A, B. Hypopygium, not macerated and macerated, respectively, left lateral view; C. Apicoventral epandrial lobe, ventral view; D. Left cercus, outer view; E. Internal appendages, left lateral view; F. Ventral lobe of surstylus, inner view; G. Dorsal lobe of surstylus, outer view. Abbreviations: apv lb = apicoventral epandrial lobe; bs sp = basal sclerite of sperm pump; d sur = dorsal lobe of surstylus; ej apod = ejaculatory apodeme; hypd = hypandrium; hypd ar = hypandrial arms; pgt = postgonite; ph = phallus; prct = proctiger; sp = sperm pump; v sur = ventral lobe of surstylus.

FIGURE 5. Sarcionus maculipennis Van Duzee, male holotype (AMNH). A. Habitus, dorsal view. B. Head, anterior view; C. Tarsus II, anterior view (arrow pointing to anterior surface of IIt 3 covered by whitish pubescence); D. Left wing; E. Labels. Original images lacked scale bars. Photographs by Agnieszka Pierwola, AMNH.

FIGURE 15. Geographic distribution of species of Paraclius Loew and Tachytrechus Haliday treated here.