Poecilobothrus Mik

SCOTT E. BROOKS, 2005, Systematics and phylogeny of Dolichopodinae (Diptera: Dolichopodidae), Zootaxa 857, pp. 1-158 : 102-107

Genus Poecilobothrus Mik

( Figs. 26 A–E, 27A–C)

Achanthipodus Rondani, 1856: 201 . Type species: Dolichopus regalis Meigen [Palaearctic], by original designation. Nomen oblitum. [I treat this name as a nomen oblitum because it has not been used as a valid taxon since 1899 (I.C.Z.N Code (1999), Article 23.9.1] (see “Remarks”).

Achantipodus: Rondani 1856: 144, incorrect original spelling of Achanthipodus Rondani, 1856 by revision of Negrobov (1991: 82).

Poecilobothrus Mik, 1878: 3 . Type species: Dolichopus regalis Meigen [Palaearctic], by original designation. Nomen protectum. [I treat this name as a nomen protectum because it has been used as a valid name in more than 25 works by at least 10 authors in the immediately preceeding 50 years and encompassing a span of not less than 10 years (I.C.Z.N Code (1999), Article 23.9.2] (see “Remarks”).

Pterostylus Mik, 1878: 4 . Type species: Gymnopternus aberrans Loew [Palaearctic], by original designation. syn. nov.

Chaetosphyria Enderlein, 1936: 109. Type species: Dolichopus regalis Meigen [Palaearctic], by monotypy (see “Remarks”).

Acanthipodus , subsequent misspelling by Bigot,1890: 266 and Stackelberg, 1941: 183.

New Combinations and Transfers. The following new combinations are hereby established: Poecilobothrus aberrans ( Loew, 1871) comb. nov. ( Pterostylus ); Poecilobothrus chrysozygos ( Wiedemann, 1817) comb. nov. ( Hercostomus ). The following species is reassigned to Poecilobothrus : Poecilobothrus bigoti Mik, 1883 .

Recognition. Poecilobothrus can be distinguished by the possession of a distinct dark metallic spot above the notopleuron, and 1 strong posterior to posteroventral preapical seta on the mid femur. Males are further distinguished by their distinctive postgonite and short, conical hypandrium, which is fused to the epandrium laterally. Females are further distinguished by the possession of an inner, medial pair of spines on T10. Some species (e.g., P. regalis , P. aberrans ) have 1 dorsal seta on hind basitarsus.

Description. Head: Vertex not distinctly excavated, 1 pair of strong vertical setae, stronger than postverticals. Frons 1.8–2.6 x wider than high, sides weakly convergent anteriorly. Face moderately narrow in male, sides converging below, narrowest just above clypeus, broad in female, nearly parallel­sided. Clypeus often produced, stronger in female, lower margin straight, not reaching lower eye margin. Palp ovoid, smaller in male, with weak setae on apical half of outer surface and a distinct apical seta. Antenna: Scape short, subconical, with distinct, acute medioventral process; pedicel short; first flagellomere subtriangular; arista dorsal, 2­segmented, second segment pubescent to plumose. Lowermost postocular seta usually longer. Postvertical setae stronger than uppermost pair of postoculars.

Thorax: Acrostichals biserial; 6 dorsocentrals, aligned or with fifth pair very weakly offset medially; 1 strong outer posthumeral, 1 weaker inner posthumeral; 2 notopleurals; 1 presutural; 1 sutural; 2 supraalars; 1 postalar. Distinct dark metallic spot above notopleuron. Upper and lower part of propleuron with cluster of fine hairs; lower part of propleuron with 1 strong prothoracic seta; pleural surface in front of posterior spiracle bare; metepisternum with distinct cluster or vertical row of fine hairs. Scutellum with 1 strong inner seta and 1 weak outer seta on lateral margin, dorsal surface usually with sparse fine hairs.

Legs: Pulvilli developed normally on all legs. Midleg: Femur with 1 anterior preapical seta, 1 strong posterior to posteroventral preapical seta about even with anterior preapical in addition to terminal posteroventral preapical that is also sometimes developed; basitarsus sometimes with 1 strong dorsal seta present (e.g., P. aberrans ). Hindleg: Coxa with strong lateral seta near middle; femur with 1 anterodorsal preapical seta; basitarsus subequal to slightly shorter than second tarsomere, 3–6 ventral seta, basiventral seta subequal or slightly longer than distal ventral setae, male with weak dentiform process posterobasally, sometimes with 1 strong dorsal seta (e.g., P. aberrans , P. regalis ).

Wing: Grayish to brownish, sometimes strongly infuscated in males (e.g., P. nobilitatus ). R2+3 nearly straight; R4+5 curved posteriorly in distal section, R2+3 and R4+5 weakly undulating in male P. nobilitatus ; distal section of M beyond crossvein dm­cu with weak to distinct sinuous anterior bend before middle, nearly straight to weakly curved posteriorly beyond bend, ending slightly to distinctly before wing apex; R4+5 and M weakly to distinctly convergent; crossvein dm­cu distinctly shorter to distinctly longer than distal section of CuA1.

Abdomen: Subconical. Male: T6 bare; S2–4 unmodified; S5 entirely membranous or with weakly sclerotized medial and lateral bands fusing with proximal margin of S6, sometimes with eversible, glandular projections (e.g., P. ducalis (Loew) , P. nobilitatus ); S6 sclerotized along lateral and anterior margin, moderately sclerotized to membranous posterolaterally; segment 7 forming well­developed peduncle; S8 teardrop­shaped to subtriangular, setose. Hypopygium ( Figs. 26 A–C, 27A–C) large. Epandrium about 1.5 x longer than high, subrectangular to subrhomboid in lateral view, with rounded, sometimes strongly projecting anteroventral margin ( Fig. 26 A); foramen positioned anterolaterally on dorsal half, well­separated from base of cerci; basiventral epandrial lobe weakly developed, rounded to subquadrate, basiventral epandrial seta present on lobe; apicoventral epandrial lobe well­developed, subquadrate to subtriangular with 1 basiventral, 1 apical and usually 1 dorsal seta (absent in P. chrysozygos ). Surstylus bilobed. Ventral lobe subrectangular to subtriangular, narrowed apicoventrally with 1 dorsobasal seta, 1 midventral seta, and 1 medial seta that is enlarged and modified in some species (e.g., P. aberrans ), 1– 3 stout apical setae. Dorsal lobe subtriangular, elongate, slightly longer than ventral lobe, laterally flattened and tapered to an acute upcurved point apically. Postgonite with anteroventral portion weakly sclerotized; posterodorsal portion well­developed, with acute ventrally curved medial lobe and 1–2 preapical lateroventral lobes ( Figs. 26 B, 27B). Proctiger brushes absent. Cercus triangular to subquadrate with long, curved marginal setae, sometimes with apical and lateral margin jagged, with elongate digitiform projections (e.g., P. regalis , Fig. 26 A). Hypandrium short, conical, slightly dorsoventrally flattened, fused to epandrium laterally near basiventral epandrial lobe ( Figs. 26 C, 27C); hypandrial apodeme present, well­developed; hypandrial arms connected to hypandrium. Sperm pump more or less cylindrical; ejaculatory apodeme well­developed, elongate and laterally flattened; basal sclerite of sperm pump heavily sclerotized, V­shaped in dorsal view. Phallus long and slender with preapical projection. Female ( Fig. 26 D,E): Terminalia about as long as abdomen. T6, T7, S6 and S7 undivided (weakly sclerotized in P. re g a l i s); T8 and S8 divided medially, tergite and sternite not fused anterolaterally. T10 divided medially into hemitergites each bearing 3–4 spines along outer margin and a single, smaller, inner medial spine ( Fig. 26 D), spines rounded and flattened apically. Upper lobe of cercus with long apical seta.

Geographical Distribution. Poecilobothrus is known from the western Palaearctic ranging from western Europe to West Siberia, south to North Africa ( Algeria) and the Middle East ( Iran).

Phylogenetic Relationships. Poecilobothrus is most closely related to Parahercostomus and Grichanov’s (1999a) Afrotropical Hercostomus group 1 based on the distinctive postgonite. As noted above (under “ Ortochile genus group”), Poecilobothrus should be regarded as a genus and not placed in Hercostomus as a subgenus.

Remarks. The name Poecilobothrus Mik, 1878 has been threatened by the senior objective synonym Achanthipodus Rondani, 1856 , which is not in use. Achanthipodus Rondani, 1856 has not, to my knowledge, been used as the valid name of this taxon since Rondani (1861: 6). Dyte (in litt.) has pointed out that Achanthipodus apparently did not come into use because of an erroneously presumed homonymy with Acanthopodus Lacépède in Pisces ( Loew, 1857: 10; Bigot, 1859: 219). Furthermore, Poecilobothrus has been used as the presumed valid name for this taxon in over 25 works, published by over 10 authors in the last 50 years and spanning more than 34 years (e.g., Dyte 1969; Couturier 1974; Dyte 1976; Negrobov & Marina 1976; d'Assis Fonseca 1978; Negrobov 1979; Negrobov 1980; Olejníček 1980; Ulrich 1981; Negrobov 1986; Pollet & Grootaert 1987; Pollet et al. 1988; Meyer & Heydemann 1990; Negrobov 1991; Pollet & Grootaert 1991; Sato 1991; Lunau 1992; Pollet et al. 1992; Evenhuis 1994; Pollet & Grootaert 1994; Pollet & Grootaert 1996; Grichanov 1997; Maes & Pollet 1997; Chandler 1998; Naglis 1999; Tulowitzki et al. 1999; Pollet 2000; Ulrich & Schmelz 2001. In accordance with Articles 23.9.1.1 and 23.9.1.2 of the I.C.Z.N. (1999), the precedence of Achanthipodus Rondani, 1856 is reversed and Poecilobothrus Mik, 1878 is the valid name of this taxon.

Negrobov (1991) listed Chaetosphyria Enderlein as a doubtful taxon because no type species was designated. However, Dyte (unpublished manuscript) points out that Enderlein (1936: 109) clearly indicated Dolichopus regalis Meigen as the only included species of Chaetosphyria, which is therefore the type species by monotypy. Stackelberg (1941) correctly listed Chaetosphyria as as synonym of Poecilobothrus .

Parent’s (1938) diagnosis of Poecilobothrus included the possession of cerci with a jagged lateral margin; however, this feature seems to only define a subgroup of species within a larger clade that also includes the newly tranferred species Poecilobothrus aberrans , P. chrysozygos and P. b i g o t i Mik.

Material Examined. Poecilobothrus aberrans (Loew) , [PA]: 1ɗ ( BMNH); 1ɗ, 1Ψ ( HNHM); Poecilobothrus bigoti Mik , [PA]: 1ɗ, 1Ψ ( MNHN); Poecilobothrus chrysozygos (Wiedemann) , [PA]: 6ɗ, 3Ψ (LEM); 1ɗ ( CNC); Poecilobothrus ducalis (Loew) , [PA]: 1ɗ, 1Ψ (LEM); Poecilobothrus fumipennis (Stannius) , [PA]: 2ɗ, 2Ψ (LEM); Poecilobothrus nobilitatus (Linnaeus) , [PA]: 5ɗ, 4Ψ ( CNC); 4ɗ, 4Ψ (LEM); Poecilobothrus regalis (Meigen) , [PA]: 1ɗ, 1Ψ ( BMNH).

Figures

FIGURE 26. Poecilobothrus regalis and P. nobilitatus: (A) P. regalis, male genitalia, left lateral view (external); (B) P. re g a l i s, male genitalia, left lateral view (internal); (C) P. regalis, male genitalia, ventral view (postgonite, surstylus and cerci not shown); (D) P. nobilitatus, female genitalia, dorsal view; (E) P. nobilitatus, female genitalia, left lateral view.