Pelastoneurus Loew

SCOTT E. BROOKS, 2005, Systematics and phylogeny of Dolichopodinae (Diptera: Dolichopodidae), Zootaxa 857, pp. 1-158 : 92-99

Genus Pelastoneurus Loew

( Figs. 22 A–E, 23A–F, 24A–E)

Paracleius Bigot, 1859: 215 , 227. Type species: Dolichopus heteronevrus Macquart , by monotypy. Senior synonym of Pelastoneurus Loew, 1861b . Suppressed by the I.C.Z.N (2004) in favor of Pelastoneurus in order to conserve stability of taxonomy and nomenclature (see Brooks et al. 2002). See comments under Paraclius Loew.

Pelastoneurus Loew, 1861b: 36 . Type species: Pelastoneurus vagans Loew [Nearctic], designation by Coquillett, 1910: 586.

Metapelastoneurus Aldrich, 1894: 152 . Type species: Metapelastoneurus kansensis Aldrich [Nearctic], by monotypy.

Sarcionus Aldrich, 1901: 341 . Type species. Pelastoneurus lineatus Aldrich [Neotropical], by original designation. syn. nov.

Phylarchus Aldrich, 1901: 342 . Type species: Phylarchus tripartitus Aldrich [Neotropical], by monotypy. Preoccupied by Phylarchus Simon, 1888 . syn. nov.

Paraclius Kertész, 1909: 230 . Type species: Dolichopus heteronevrus Macquart , automatic. Unjustified emendation of Paracleius Bigot, 1859 .

Proarchus Aldrich, 1910: 100 . Type species: Phylarchus tripartitus Aldrich , automatic. N. name for Phylarchus Aldrich, 1901 . syn. nov.

Palastoneurus, subsequent misspelling by Parent (1933a: 249).

Pelastroneurus, subsequent misspelling by Robinson (1964: 177).

New Combinations and Tranfers. The following new combinations are hereby established: Pelastoneurus acutispina ( Van Duzee, 1931) comb. nov. ( Sarcionus ); Pelastoneurus currani ( Van Duzee, 1931) comb. nov. ( Sarcionus ); Pelastoneurus obtusus ( Van Duzee, 1933) comb. nov. ( Sarcionus ); Pelastoneurus pectinicauda ( Van Duzee, 1934) comb. nov. ( Sarcionus ); Pelastoneurus pusillus ( Macquart, 1846) comb. nov. ( Dolichopus ); Pelastoneurus rotundicornis ( Van Duzee, 1931) comb. nov. ( Sarcionus ); Pelastoneurus tripartitus ( Aldrich, 1901) comb. nov. ( Phylarchus ). The following species is reassigned to Pelastoneurus : Pelastoneurus lineatus Aldrich, 1896 . The re­establishment of this combination renders Pelastoneurus lineatus de Meijere, 1916 a junior secondary homonym for which the replacement name Pelastoneurus neolineatus nom. nov. is hereby proposed.

Recognition. Most species currently assigned to Pelastoneurus on a global scale may be distinguished by the possession of a strong anterior bend in wing vein M and plumose arista; however, many Old World species do not appear to be congeneric with those of the New World. The lineage of Pelastoneurus including the type species P. vagans appears to be restricted to the New World and can be recognized by the following combination of characters: clypeus usually strongly bulging and subequal in height to face (often taller than face in females), proboscis large, arista plumose, 5 dorsocentral setae, wing vein M beyond crossvein dm­cu usually with strong anterior bend and distinctly convergent with R4+5, hind coxa usually with lateral seta near apex. Pelastoneurus is close to Stenopygium and Platyopsis with which it shares a similarly modified clypeus.

Description (based on P. vagans lineage). Head: Usually thick in lateral view. Vertex usually flat to weakly excavated, sometimes strongly excavated (e.g., P. currani ), 1 pair of strong vertical setae, stronger than postverticals. Frons about 2– 3 x wider than high, sides weakly to distinctly convergent anteriorly. Face and clypeus usually broad, occasionally narrow (e.g., male P. lineatus ), broader in female; face usually concave with sides subparallel to convergent below; clypeus usually strongly bulging and subequal in height to face in both sexes (often taller than face in female), occasionally distinctly shorter than face and weakly bulging in male (e.g., P. lineatus ), widening below, lower margin straight to rounded or subtriangular, ending above or extending slightly beyond lower eye margin. Palp usually large and subtriangular with weak hairs on outer surface, usually with a weakly differentiated to distinct apical seta. Proboscis usually large and thick, occasionally relatively small (e.g., P. lineatus ). Antenna: Scape short, subconical, with well­developed acute medioventral process and weaker acute process ventrally; pedicel short; first flagellomere rounded or ovoid to subquadrate, occasionally pointed apically, shorter in female; arista dorsal, usually near base, 2­segmented, basal segment occasionally elongate in male (e.g., P. neglectus Wheeler ), distal segment plumose, dorsal and ventral hairs longer than lateral hairs and usually widely spaced. Lower postocular setae sometimes flattened (e.g., P. vagans ), lowermost seta usually stronger. Postvertical setae slightly to distinctly stronger than uppermost pair of postoculars.

Thorax: Acrostichals biserial; 5 dorsocentrals, aligned or with fourth pair weakly offset medially; 1 outer posthumeral, 1 weaker inner posthumeral, sometimes indistinct; 2 notopleurals; 1 presutural; 1 sutural; 2 supraalars; 1 postalar. Scutum occasionally with black spot or region above notopleuron, sometimes also with similar spot beside postpronotum and at wing base (e.g., P. tripartitus ). Upper and lower part of propleuron with fine to coarse hairs; upper part of propleuron sometimes with several stronger setae amongst hairs; lower part of propleuron with 1 strong prothoracic seta; pleural surface in front of posterior spiracle bare; metepisternum with a cluster or row of fine hairs. Scutellum with 1 strong inner seta and 1–2 small outer seta on lateral margin, often with 1 fine ventral seta (occasionally 2–3 setae) even with or slightly medial to strong inner seta (e.g., P. vagans ), occasionally with several weak marginal hairs.

Legs: Pulvilli usually developed normally on all legs, occasionally enlarged on foreleg of male (e.g., P. umbripictus ). Foreleg: Femur usually with well­developed posterior preapical seta, or a series of progressively longer setae; tarsus of male often with dense pile ventrally, basitarsus occasionally with distinct basiventral seta (e.g., P. umbripictus ), inner claw enlarged in males of some species (e.g., P. unguiculatus (Aldrich)) . Midleg: Femur with 1 anterior or anterodorsal preapical seta, males occasionally with long anteroventral hairs or setae (e.g., P. nititus Van Duzee, P. tripartitus ) or basiventral piliferous patch (e.g., P. unguiculatus ). Hindleg: Coxa with strong lateral seta usually near apex, sometimes slightly below middle (e.g., P. tripartitus ); femur with 1 anterodorsal preapical seta and usually 1 distinct anteroventral preapical seta, occasionally with 1 weak anterior seta near apex (e.g., P. aldrichi Van Duzee ), males of some species with long basiventral hairs (e.g., P. nitidus ), or 2–3 strong setae along middle third (e.g., P. tripartitus ); tibia of male with ctenidia usually enlarged with thickened or modified spinules (e.g., P. vagans ), occasionally with distinct hook­like posteroapical process (e.g., P. umbripictus ); basitarsus slightly to distinctly shorter than second tarsomere, usually with 2–3 ventral setae, basiventral seta sometimes distinct, male usually lacking a distinct posterobasal process.

Wing: Grayish to brownish, occasionally infuscated near veins, or with dark spots or bands (e.g., P. umbripictus , P. turbidus ). Costa occasionally swollen basally before R1 (e.g., P. unguiculatus ); R2+3 often weakly sinuous basally, relatively straight in distal section; R4+5 relatively straight, usually with distinct posterior curve in distal section; distal section of M beyond crossvein dm­cu usually with strong anterior bend, ending well before wing apex, occasionally with weak bend (e.g., P. unguiculatus ), rarely straight and ending at apex (e.g., P. tripartitus ); R4+5 and M usually strongly convergent, rarely subparallel (e.g., P. tripartitus ); crossvein dm­cu subequal to distinctly shorter than distal section of CuA1.

Abdomen: Subconical, occasionally short and contracted in male (e.g., P. b re v i s Robinson). Male: T6 bare; S2 and S3 unmodified to weakly sclerotized, often emarginate and membranous posteromedially; S4 emarginate and membranous posteromedially; S5 usually membranous medially; S6 mainly membranous, sclerotized along anterior margin and often fused to T6 laterally; segment 7 forming well­developed peduncle; S8 usually subquadrate to rounded, setose. Hypopygium ( Figs. 22 A–C, 23A–D, 24A–C) large, usually about as long as abdomen, often held in ventral pocket of abdomen. Epandrium variable in shape, ovoid to subrectangular or subtriangular in lateral view, about 1.5–3.0 x longer than high, occasionally with keel­like process above apicoventral epandrial lobe/setae (e.g., P. lineatus , P. umbripictus , Fig. 23 A); foramen positioned anterolaterally, usually well­separated from base of cerci, rarely close to base of cerci (e.g., P. kansensis ); basiventral epandrial lobe usually absent ( Figs. 22 A, 24A), occasionally weakly developed (e.g., P. lineatus Fig. 23 A), small to minute basiventral epandrial seta usually present along infolded ventral epandrial margin, seta positioned near middle ( Figs. 23 A,D, 24A,C) or close to base of apicoventral epandrial lobe where the hypandrial arm connects to the epandrium ( Fig. 22 A,C), occasionally absent; apicoventral epandrial lobe absent or weakly developed as an elevated ridge (e.g., P. tripartitus , Fig. 24 A) to well­developed (e.g., P. vagans , Fig, 22A), with 2–8 setae, often with one or more branched setae, setae occasionally scimitar­shaped (e.g., P. lineatus , Fig. 23 A). Surstylus bilobed. Ventral and dorsal lobe variable, broad to slender and digitiform; ventral lobe often with bulbous basal projection (e.g., P. l a e t u s). Postgonite: anteroventral portion usually well­sclerotized with well­defined margin, usually dorsoventrally flattened, narrow to broad in ventral view, sometimes with bulbous base positioned below sperm pump (e.g., P. tripartitus Fig. 24 B); posterodorsal portion well­developed, with single lobe (e.g., P. lineatus , P. tripartitus Figs. 23 B, 24B), or with dorsal and ventral lobe (e.g., P. vagans Fig. 22 B), dorsal lobe occasionally strongly upturned. Proctiger brushes usually present ( Figs. 22 B, 23B,C), rarely absent (e.g., P. tripartitus , Fig. 24 B). Cercus variable in shape and size. Hypandrium long, variable in shape, more or less trough­like, usually asymmetrical, often complex with multiple lobes or projections, with narrow sclerotized or membranous connection to epandrium basiventrally, free laterally; hypandrial apodeme usually absent or indistinct, sometimes present and well­developed; hypandrial arms not connected to hypandrium, usually weakly connected to epandrium near basiventral epandrial seta and/or base of apicoventral epandrial lobe ( Figs. 22 B, 23B, 24B). Sperm pump usually small and round; ejaculatory apodeme elongate, laterally flattened, apex sometimes split medially; basal sclerite of sperm pump usually elongate and tubular ( Figs. 22 B, 23B), occasionally relatively short ( Fig. 24 B) and V­shaped in dorsal view (e.g., P. tripartitus , P. umbripictus ). Phallus slen­ der in basal part, apical half highly variable in structure, often serrate (e.g., P. vagans Fig. 22 B), and/or with well­developed projections (e.g., P. lineatus Fig. 23 B), sometimes complex, multilobate and intertwined with hypandrium (e.g., P. brasiliensis Van Duzee ). Female ( Figs. 22 D,E, 23E,F, 24D,E): T6 and T7 divided medially, S6 and S7 usually undivided, occasionally divided (e.g., P. brasiliensis ); T8 and S8 divided medially, tergite and sternite fused anterolaterally forming a narrow sclerite ( Figs. 22 E, 23E, 24E). Furca usually present, shape variable, often weakly sclerotized. T10 divided medially into hemitergites each bearing 4–7 spines, spines pointed or rounded apically.

Geographical Distribution. Species of Pelastoneurus have been described or recorded from the Nearctic, Neotropical, Afrotropical and Oriental regions as well the Hawaiian islands. However, many species from outside of the New World appear to be questionably placed in this genus.

Phylogenetic Relationships. Pelastoneurus (in the sense of the P. vagans lineage) seems to be most closely related to Stenopygium based on the possession of a pair of proctiger brushes and a well­sclerotized anteroventral portion of the postgonite; however this relationship is not supported in all of the equally parsimonious trees.

Based on the examination of several Afrotropical and Oriental Pelastoneurus , and a survey of descriptions in the literature, it appears that many of these Old World species are not congeneric with the concept of Pelastoneurus adopted here (i.e. the lineage including the type species P. vagans ) and probably require the establishment of additional genera. For the present, these species are left in Pelastoneurus until a more detailed phylogenetic study of the world species of this genus is completed.

Remarks. Despite the application to the I.C.Z.N. by Brooks et al. (2002) to suppress Paracleius Bigot in favor of the junior synonym Pelastoneurus Loew, Grichanov (2004) used Paraclieus Bigot as the valid name for this genus in his monograph of the Afrotropical Dolichopodinae . Grichanov (2004) also considered Paraclius Loew to be a synonym of Paraclieus Bigot and transferred all Afrotropical species of Paraclius Loew to Paracleius Bigot. The Commission has since suppressed Paracleius Bigot (I.C.Z.N. 2004), and consequently all species names newly proposed by Grichanov (2004) in Paracleius Bigot must be combined with Pelastoneurus . Similarly, all previously proposed species names combined with Paracleius by Grichanov (2004) must be recombined with their former generic name.

Both syntypes of Pelastoneurus tripartitus (formerly in Proarchus ) are in poor condition. One specimen is missing its head, left wing, right tibia and has damage to the dorsum of the thorax. The other specimen is in slightly better shape, but has damage to both wings and is missing the tibiae and tarsi from the hind legs. Recently, I found a male in the miscellaneous holdings of the USNM from the western tip of Jamaica, near Negril.

Material Examined. Pelastoneurus abbreviatus Loew , [NE]: 9ɗ, 6Ψ ( CNC); Pelastoneurus acutispina (Van Duzee) , [NT]: 1Ψ paratype ( AMNH); 1Ψ paratype ( CAS); Pelastoneurus aldrichi Van Duzee , [NE]: 1ɗ paratype, 2ɗ, 2Ψ ( CAS); Pelastoneurus argentifer Aldrich , [NT]: 2ɗ, 2Ψ ( USNM); 1ɗ, 1Ψ ( CAS); Pelastoneurus barri Harmston , [NE]: 2ɗ paratypes, 2Ψ paratypes ( CAS); Pelastoneurus bigeminatus Aldrich , [NT]: 1ɗ, 1Ψ ( USNM); Pelastoneurus brasilensis Van Duzee , [NT]: 1ɗ paratype, 1Ψ paratype ( CAS); Pelastoneurus brevis Robinson , [NE]: 3ɗ, 2Ψ ( CAS); Pelastoneurus caeruleus Va n Duzee, [NT]: 1ɗ paratype ( CAS); 1ɗ, 1Ψ ( USNM); Pelastoneurus confusibilis Parent , [AF]: 1ɗ paratype, 2Ψ paratypes, 1ɗ ( ISNB); Pelastoneurus congoensis Parent , [AF]: 4ɗ, 2Ψ ( MRAC); Pelastoneurus costalis Van Duzee , [NT]: 1ɗ, 1Ψ ( USNM); Pelastoneurus currani Van Duzee , [NT]: 4ɗ paratypes ( AMNH); 1ɗ paratype ( CAS); Pelastoneurus cyaneus Wheeler , [NE]: 4ɗ, 2Ψ ( CAS); 2ɗ ( CNC); Pelastoneurus dissimilipes Wheeler , [NE]: 3ɗ, 2Ψ ( CAS); Pelastoneurus diversifemur Parent , [AF]: 3ɗ, 2Ψ ( ISNB); Pelastoneurus dorsalis Van Duzee , [NE, NT]: 1ɗ ( CAS); Pelastoneurus emasculatus Parent , [AF]: 2ɗ paratypes, 2Ψ paratypes ( ISNB); Pelastoneurus floridanus Wheeler , [NE]: 3ɗ, 2Ψ ( CAS); Pelastoneurus intactus Becker , [OR]: 2ɗ ( BMNH); Pelastoneurus kansensis (Aldrich) , [NE]: 3ɗ, 2Ψ ( USNM); 1ɗ ( CAS); 1ɗ (LEM); Pelastoneurus laetus Loew , [NE]: 4ɗ, 3Ψ ( CNC); Pelastoneurus lamellatus Loew , [NE]: 4ɗ ( CAS); 2ɗ ( CNC); Pelastoneurus lineatus Aldrich , [NT]: 3ɗ syntypes, 1Ψ syntype, 5ɗ, 7Ψ ( USNM); Pelastoneurus longicauda Loew , [NE]: 1ɗ, 1Ψ ( USNM); Pelastoneurus lugubris Loew , [NE, NT, AU]: 2ɗ ( CAS); 1ɗ ( CNC); Pelastoneurus micrurus Parent , [AF]: 3ɗ ( MRAC); Pelastoneurus neglectus Wheeler , [NE]: 3ɗ, 2Ψ ( USNM); 2ɗ ( CAS); Pelastoneurus nigricornis Van Duzee , [NE]: 1ɗ ( USNM); Pelastoneurus nigrifacies Van Duzee , [NT]: 1ɗ ( CAS); 1ɗ ( USNM); Pelastoneurus nitidus Van Duzee , [NT]: 2ɗ paratypes, 1Ψ paratype ( CAS); Pelastoneurus pectinatus Van Duzee , [NT]: 2ɗ paratypes, 1Ψ paratype ( USNM); 1ɗ paratype ( CAS); Pelastoneurus pectinicauda (Van Duzee) , [NT]: 1ɗ, 1Ψ ( AMNH); Pelastoneurus pedunculatus Parent , [AF]: 6ɗ ( MRAC); Pelastoneurus rotundicornis (Van Duzee) , [NT]: ɗ holotype ( AMNH); 4ɗ paratypes, 1Ψ paratype ( AMNH); 1ɗ paratype, 1Ψ paratype ( CAS); Pelastoneurus taeniatus Becker , [NE, NT]: 2ɗ, 2Ψ ( USNM); Pelastoneurus tibialis Van Duzee , [NE]: 4ɗ, 4Ψ ( CNC); Pelastoneurus tripartitus (Aldrich) , [NT]: 2Ψ syntypes ( BMNH); 1ɗ ( USNM); Pelastoneurus turbidus Becker , [NT]: 1ɗ ( USNM); Pelastoneurus umbricola (Parent) , [AF]: 2Ψ ( ISNB); Pelastoneurus umbripictus Becker , [NE, NT]: 2ɗ, 2Ψ ( USNM); Pelastoneurus unguiculatus (Aldrich) , [NT]: 3ɗ, 2Ψ ( CNC); Pelastoneurus vagans Loew , [NE, NT]: 12ɗ, 6Ψ ( CNC) 2ɗ, 2Ψ (LEM); Pelastoneurus varius (Walker) , [NE]: 4ɗ, 1Ψ ( CAS); 2ɗ ( CAS); Pelastoneurus wheeleri Melander , [NE]: 3ɗ, 2Ψ ( CAS); “ Sarcionus ” flavicoxa (Aldrich) , [NT]: 1ɗ syntype, 1Ψ syntype ( BMNH); “ Sarcionus ” intermedius (Van Duzee) , [NT]: 1ɗ paratype ( AMNH); “ Sarcionus ” maculatus (Van Duzee) , [NT]: ɗ holotype, 1Ψ paratype ( USNM).

Figures

FIGURE 22. Pelastoneurus vagans: (A) Male genitalia, left lateral view (external); (B) Male genitalia, left lateral view (internal); (C) Male genitalia, ventral view (postgonite, surstylus and cerci not shown); (D) Female genitalia, dorsal view; (E) Female genitalia, left lateral view.

FIGURE 23. Pelastoneurus lineatus: (A) Male genitalia, left lateral view (external); (B) Male genitalia, left lateral view (internal); (C) Male genitalia, proctiger brush, lateral view; (D) Male genitalia, ventral view (postgonite, surstylus and cerci not shown); (E) Female genitalia, dorsal view; (F) Female genitalia, left lateral view.

FIGURE 24. Pelastoneurus tripartitus: (A) Male genitalia, left lateral view (external); (B) Male genitalia, left lateral view (internal); (C) Male genitalia, ventral view (postgonite, surstylus and cerci not shown); (D) Female genitalia, dorsal view; (E) Female genitalia, left lateral view.