Tachytrechus Haliday

SCOTT E. BROOKS, 2005, Systematics and phylogeny of Dolichopodinae (Diptera: Dolichopodidae), Zootaxa 857, pp. 1-158 : 120-126

Genus Tachytrechus Haliday

( Figs. 33 A–G, 34A–E, 35A–E, 36A–E) Ammobates Stannius, 1831a: 33 . Type species: Ammobates notatus Stannius , designation by Rondani, 1856: 143. Preoccupied by Ammobates Latreille, 1809 . Erroneously treated as an incorrect original spelling of Tachytrechus Stannius, 1831 by Pollet et al. (2004).

Tachytrechus Stannius, 1831c: 261 (nomen nudum) (see “Remarks”).

Tachytrechus Haliday, 1851: 173 . Type species: Ammobates notatus Stannius [Palaearctic], automatic. Replacement name for Ammobates Stannius, 1831a .

Hammobates , subsequent misspelling by Rondani, 1856: 143.

Stannia Rondani, 1857: 14 . Type species: Ammobates notatus Stannius , automatic. Unnecessary n. name for Ammobates Stannius, 1831a .

Gongophora Philippi, 1875: 86 . Type species: Gongophora medinae Philippi [Neotropical], by monotypy. Synonymized by Robinson (1970b).

Congophora: Philippi, 1875: 86, incorrect original spelling by revision of Pollet et al. (2004).

Polymedon Osten Sacken, 1877: 317 . Type species: Polymedon flabellifer Osten Sacken [Nearctic], by monotypy. Synonymized by Robinson (1970b).

Macellocerus Mik, 1878: 5 . Type species: Tachytrechus moechus Loew [Nearctic], by original designation.

Psilischium Becker, 1922a: 93 . Type species: Psilischium laevigatum Becker [Neotropical], by monotypy. Synonymized by Robinson (1970b).

Gonioneurum Becker 1922a: 98 . Type species: Gonioneurum varum Becker [Neotropical], by monotypy. syn. nov.

Syntomoneurum Becker, 1922a: 123 . Type­species Syntomoneurum alatum Becker [Neotropical], by monotypy. syn. nov.

Tetrechus , error by Van Duzee (1924: 43).

Gongrophora , subsequent misspelling by Porter (1929: 230), repeated by Robinson (1970b: 53).

Syntormoneurum , subsequent misspelling by Parent, (1931: 17; 1934c: 273; 1954: 226).

Tachyterechus , subsequent misspelling by Dyte (1975: 238).

New Combinations. The following new combinations are hereby established: Tachytrechus alatus ( Becker, 1922a) comb. nov. ( Syntomoneurum ); Tachytrechus analis ( Parent, 1954) comb. nov. ( Syntomoneurum ); Tachytrechus beckeri ( Parent, 1931) comb. nov. ( Syntomoneurum ); Tachytrechus giganteus (Brooks in Brooks & Wheeler, 2002) comb. nov. ( Syntomoneurum ); Tachytrechus varus ( Becker, 1922a) comb. nov. ( Gonioneurum ).

Recognition. Most species of Tachytrechus can be recognized by the clypeus, which usually extends to or beyond the lower eye margin and/or is rounded below. Other species can be recognized by the face narrowed below the antennae and widening below, 1 very strong basiventral seta on the hind basitarsus, usually 2 or more anterodorsal preapical setae on the hind femur, and by the distinctive upturned and flared postgonite of the male genitalia.

Description. Head: Usually unmodified, occasionally anteroposteriorly flattened (e.g., T. laevigatus ) or dorsoventrally elongated (e.g., male T. auratus (Aldrich) , T. moechus ). Dorsal part of occiput occasionally slightly concave (e.g., T. aldrichi ). Vertex usually distinctly excavated, sometimes weakly or strongly, 1 pair of vertical setae, usually stronger than postverticals, occasionally reduced ( T. seriatus Robinson , males of T. laevigatus , T. flabellifer , T. transversus (Van Duzee)) . Frons about 2– 5 x wider than high, sides weakly to strongly convergent anteriorly, some males (e.g., T. greeni Foote, Coulson and Robinson , T. moechus and related species) with dense tuft of velvety hairs between antennal socket and eye margin near frons­face boundary. Face very narrow to broad, usually narrowest below antennae or near middle and widening below, sometimes parallel­sided, often broader in female, boundary with clypeus indistinct in some species; clypeus usually extending to or beyond lower margin of eyes, sometimes far beyond margin in males (e.g., T. flabellifer ), occasionally not reaching lower margin of eyes (e.g., T. costalis (Becker) , male T. olympiae (Aldrich) , females of some species), usually broad (at least as broad as face), usually not produced, occasionally weakly produced in females of some species, usually rounded or subtriangular below, occasionally subquadrate. Palp usually small, occasionally large (e.g., T. castus , T. transversus ), ovoid, apex rounded to subtriangular, with fine setae on outer surface, distinct apical seta present or absent, occasionally very strong (e.g., T. transversus ). Proboscis sometimes enlarged and projecting (e.g., T. giganteus ). Antennae sometimes inserted very high on head (e.g., male T. moechus ); scape usually subconical, short to elongate and somewhat flattened laterally, acute medioventral process usually well­developed, sometimes indistinct, males of some species (e.g., T. moechus ) with scape elongate, thickened and densely setose dorsally; pedicel usually short, apical margin often with 1 strong dorsal seta and/or 1–2 strong ventral setae, pedicel sometimes greatly reduced and funnel­shaped with apical ring of setae reduced or absent in male (e.g., T. moechus , T. laevigatus ); first flagellomere round or ovoid to subtriangular; arista dorsal to subapical, usually 2­segmented, occasionally 1­segmented in male (e.g., T. binodatus Loew ), distal segment glabrous, bare or shortly pubescent, sometimes elongated with apical lamella in male (e.g., T. moechus ), rarely with second lamella near middle (e.g., T. binodatus ). Postocular setae well­developed, occasionally finer in male, lowermost seta/setae often stronger, postgenal area behind lower postoculars occasionally with dense setae. Postvertical setae usually stronger than uppermost pair of postoculars.

Thorax: Acrostichals biserial, occasionally absent in male (e.g., T. flabellifer ); anterior part of notum sometimes with surface setae extending to level of transverse suture, with anterior pair of dorsocentrals arising near level of transverse suture (e.g., T. albonotatus (Loew)) ; 5–6 dorsocentrals, penultimate pair in line or offset medially; posterior mesonotum in front of scutellum usually bare, rarely with fine setae (e.g., T. aldrichi ); 1 strong outer posthumeral, 1 weaker to sometimes indistinct inner posthumeral; usually 2 notopleurals, posterior notopleural sometimes strongly reduced (e.g., T. aldrichi , T. flabellifer ), occasionally absent (e.g., T. alatus ), rarely with 1–2 fine setae between anterior and posterior notopleural (e.g., T. nigripes (Aldrich) , T. parvicauda (Van Duzee)) ; 1 presutural, occasionally indistinct (e.g., T. calyptopygeus Robinson ); 1 sutural; 2 supraalars; 1 postalar. Upper and lower part of propleuron with very fine to relatively coarse hairs, sometimes dense and/or long, upper part of propleuron occasionally with 2–3 strong setae amongst hairs (e.g., T. tessellatus (Macquart)) , lower part of propleuron usually with 1 strong prothoracic seta, occasionally reduced (e.g., T. utahensis Harmston & Knowlton ); pleural surface in front of posterior spiracle usually bare, occasionally with a cluster of fine hairs (e.g., T. aldrichi , T. angustipennis Loew , T. granditarsis Greene , T. utahensis , T. seriatus ); metepisternum usually with a cluster of several fine hairs, sometimes bare or with 1–2 hairs. Scutellum with 1 strong inner seta and 1 small to moderately­sized outer seta (up to about 0.5 x inner seta) on lateral margin, outer seta occasionally absent (e.g., T. flabellifer ), dorsum and/or posterior margin occasionally with fine setae (e.g., T. aldrichi , T. parvicauda ).

Legs: Pulvilli usually present on all legs, occasionally absent on mid­ and hindleg (e.g., T. alatus group). Foreleg: Femur occasionally with 1 strong basiventral seta close to joint with trochanter (e.g., T. alatus group), sometimes with strong anterior preapical seta (e.g., T. castus ); tarsus often laterally flattened in both sexes. Foreleg often modified in male: femur and tibia with variably modified setae and hairs; femur sometimes swollen basally, occasionally with bare patch on medial surface (e.g., T. binodatus , T. utahensis ) and/or opaque, velvety, dark spot basally (e.g., T. olympiae ); tibia occasionally thickened or strongly flattened dorsoventrally (e.g., T. aldrichi , T. laevigatus , T. fusiformis (Becker)) or laterally (e.g., T. laticrus Van Duzee ); tarsus occasionally laterally flattened with modified dorsal setae (e.g., T. ammobates (Haliday)) , males of some species with pile ventrally (e.g., T. planifacies Robinson , T. seriatus ), occasionally with whitish or silver pollinosity in male; pulvilli sometimes larger in male (e.g., T. calyptopygeus ), outer pulvillus occasionally larger than inner pad (e.g., male T. binodatus , T. olympiae ). Midleg: Coxa of male occasionally with cluster of 2–3 strong setae anteriorly (e.g., T. alatus group). Femur with 1–5 anterior preapical setae, sometimes with weak anteroventral and posteroventral setae, chaetotaxy variable, occasionally with long setae ventrally (e.g., T. laevigatus , T. ammobates , T. ripicola Loew , male T. auratus ), males of some species (e.g., T. notatus ) with ventral tubercle; tibial chaetotaxy occasionally modified in male (e.g., T. binodatus ); tarsus usually unmodified, occasionally tarsomeres enlarged and flattened in male (e.g., T. granditarsis ). Hindleg: Coxa with strong lateral seta positioned slightly above to slightly below middle, seta occasionally reduced (e.g., T. laevigatus ); femur with 1–6 strong anterodorsal preapical setae, distal seta sometimes shifted anteriorly, occasionally with a cluster of up to 10 preapical setae (e.g., T. ammobates ), preapical seta sometimes shifted proximally (e.g., T. vanduzeei Robinson ), femur sometimes laterally flattened and wide, occasionally with ventral setae (e.g., T. novus Parent ); tibia usually unmodified, occasionally with modified setae in male (e.g., T. angustipennis ), male with variably developed posteroapical process, usually dentiform or claw­like, occasionally flat and subquadrate (e.g., T. flabellifer ); basitarsus slightly longer to slightly shorter than second tarsomere, with a well­differentiated, strong, thick basiventral seta, longer than width of basitarsus, often at extreme base of tarsomere, male with variably developed dentiform to hook­like posterobasal process.

Wing: Hyaline to brownish or grayish, occasionally with infuscated regions near bend in M and at dm­cu (e.g., T. intermedius Becker , T. notatus ), or with apical spot usually only in male (e.g., T. floridensis Aldrich , T. simulatus Greene , T. vorax Loew ). Costa of male often with swelling or pterostigma proximal to insertion of R1, occasionally large, flaplike, covering middle part of R1 (e.g., T. flabellifer , T. dilaticosta (Van Duzee) , T. nigrifemoratus (Van Duzee) , T. nimus (Aldrich)) , and/or with ventral invagination (e.g., T. canacolli Brooks ), pterostigma weakly developed in some females, costa occasionally swollen beyond R1 (e.g., T. costalis ); R2+3 straight to weakly sinuous, occasionally with posterior bend in distal section; R4+5 with slight to strong posterior curve in distal section; distal section of M beyond crossvein dm­cu with strong to weak obtuse anterior bend before or near middle, occasionally distinctly S­shaped, M nearly straight to strongly arcuate beyond bend, sometimes bent anteriorly at apex (e.g., T. utahensis ), usually ending distinctly before wing apex close to R4+5, occasionally ending at or near wing apex (e.g., T. laevigatus , T. castus ); R4+5 and M weakly to strongly convergent, occasionally subparallel (e.g., T. laevigatus , T. castus ); crossvein dm­cu distinctly shorter to distinctly longer than distal section of CuA1, usually about equal, sometimes bent or sinuous, distal section of CuA1 straight or curved toward wing margin; wing apex rather pointed in males of a few species (e.g., T. vorax , T. floridensis ); calypter of male sometimes with dense cluster of elongate setae (e.g., T. dilaticosta , T. flabellifer , T. nimus ).

Abdomen: Subconical, weakly to strongly tapering distally. Male: T5 occasionally with large posterior membranous region (e.g., T. alatus ), T6 bare, occasionally membranous posteriorly; S2 unmodified or weakly emarginate and membranous anteriorly and/or posteriorly; S3 unmodified or weakly to strongly emarginate and membranous posteriorly; S4 unmodified to strongly emarginate and membranous posteriorly; S5 weakly sclerotized to entirely membranous, sometimes with narrow medial sclerotization often fusing with S6 posteriorly, occasionally with an eversible glandular structure (e.g., T. indianus (Harmston & Knowlton) , T. longiciliatus (Van Duzee) , T. transversus ); S6 entirely membranous to weakly sclerotized, usually more strongly sclerotized along anterior margin, sometimes fused with T6 laterally; segment 7 forming well­developed peduncle, occasionally elongate (e.g., T. olympiae ); S8 heart­shaped to subtriangular, sometimes elongate­subtriangular, rarely ovoid, occasionally with short pedunculate base, almost entirely setose to sparsely setose laterally. Hypopygium ( Figs. 33 A–E, 34A–C, 35A–C, 36A–C) large. Epandrium 1.0–1.8 x as long as high, usually longer than high, shape variable, sometimes flattened dorsally (e.g., T. olympiae ); foramen usually positioned anterolaterally, occasionally closer to middle, well­separated from base of cerci; basiventral epandrial lobe highly variable, weak to extremely well­developed, sometimes complex with multiple projections (e.g., T. moechus , Fig. 34 A,C), right and left lobes symmetrical or asymmetrical, sometimes in close association with hypandrium, usually 1 basiventral epandrial seta present, sometimes absent (e.g., T. notatus , Fig. 33 A,C), occasionally with 2 setae; flap­like epandrial projection between basiventral and apicoventral lobes sometimes developed (e.g., T. mchughi Harmston , T. tenuiseta Greene ); apicoventral epandrial lobe variable, weak to well­developed, with 2 setae, upper/medial seta often thickened and frayed apically ( Fig. 36 A), sometimes with membranous sac arising medially to dorsally near base of apicoventral lobe (e.g., T. notatus , T. moechus , Figs. 33 C, 34C), occasionally with acute process above apicoventral epandrial lobe (e.g., T. laevigatus , Fig. 35 A,C). Surstylus bilobed. Ventral lobe variable, more or less digitiform, often ridged ventrally, occasionally dorsoventrally flattened, usually with 1 distinct, dark mediodorsal seta, 1 stout or flattened apical seta, occasionally with strong ventral preapical seta. Dorsal lobe variable, digitiform to club­shaped and usually enlarged apically, sometimes slightly flattened dorsoventrally, often with patch of setae near apex, occasionally with 1–2 plumose setae (e.g., T. laevigatus , Fig. 35 B). Postgonite with anteroventral portion weakly to moderately sclerotized, bifurcate anteriorly; posterodorsal portion well­developed with apex distinctly upturned and flared laterally ( Fig. 33 D,E), rarely absent (e.g., T. nigrifemoratus ). Proctiger brushes absent. Cercus large to rather small, shape and setation variable. Hypandrium variable, usually well­developed, occasionally reduced or weakly sclerotized (e.g., T. auratus , T. olympiae ), symmetrical or asymmetrical, free laterally with sclerotized or membranous connection to epandrium basally, occasionally closely associated with basiventral epandrial lobes but not distinctly fused to lobes laterally (e.g., T. vorax ); hypandrial apodeme absent; hypandrial arms connected to hypandrium, sometimes weakly. Sperm pump spherical to cylindrical, sometimes narrowed basally (e.g., T. nimus ); ejaculatory apodeme rodlike, apex flared and more or less T­shaped in dorsal view, sometimes with elongated, flexed basal projections (e.g., T. beckeri , Fig. 36 B); basal sclerite of sperm pump variably sclerotized, with lateral subtriangular projections, often V­shaped in dorsal view. Phallus elongate and slender to relatively short and thick, sometimes heavily sclerotized, simple or with variably developed projections, occasionally serrate, some species with modified apex. Female ( Figs. 33 F,G, 34D,E, 35D,E, 36D,E): Terminalia usually short and broad (e.g., T. notatus ), sometimes more elongate (e.g., T. indianus ). T6 and T7 divided medially; S6 usually complete, often emarginate anteriorly, occasionally divided medially; S7 complete or divided medially; T8 divided medially; S8 usually divided medially, sometimes complete, occasionally forming a well­sclerotized apicoventral plate­like process (e.g., T. ammobates ); T8 and S8 separate, weakly connected or fused anterolaterally forming a short blunt projection or a broad, rounded process (process sometimes present in the absence of fusion of T8 and S8) ( Figs. 33 G, 34E). Furca present or absent, variable in structure, often well­developed. T10 divided medially into hemitergites each bearing 3–8 spines along outer margin, spines short or long, rounded or pointed apically, occasionally with a pair of inner medial spines ( Figs. 34 D, 36D). Upper lobe of cercus rounded or pointed apically, often with short to minute apical seta.

Geographical Distribution. Tachytrechus has a worldwide distribution, but is most diverse in the Neotropical Region.

Phylogenetic Relationships. Tachytrechus is part of the clade that also includes Cheiromyia , Paraclius , Stenopygium , Pelastoneurus and Platyopsis based on the loss of the hypandrial apodeme (character 67:0, see discussion above under “ Tachytrechus genus group”).

Remarks. The generic concept of Tachytrechus is expanded here to include the Neotropical genera Syntomoneurum and Gonioneurum . Syntomoneurum was originally placed in the Hydrophorinae by Becker (1922a); however, Ulrich (1981) considered it to be closely related to Tachytrechus and transferred it to the Dolichopodinae . Brooks & Wheeler (2002) confirmed Ulrich’s (1981) hypothesis of a close relationship between Tachytrechus and Syntomoneurum and further hypothesized that Syntomoneurum may represent a species group within Tachytrechus , making the latter paraphyletic. This hypothesis is supported by the results of the cladistic analysis and Syntomoneurum is considered to be congeneric with Tachytrechus .

Becker (1922a) erected the monotypic genus Gonioneurum from Colombia based on the unusual wing venation of G. v a r u m (i.e. M and R4+5 bent anteriorly beyond crossvein dm­cu and subparallel to each other). Becker deposited the two male syntypes in the Hungarian Museum. These specimens were subsequently destroyed during the Hungarian Revolution in 1956 (M. Földvàri, pers. comm.) and no other specimens are known. However, based on Becker’s description, G. v a r u m possesses an elongate clypeus extending beyond the lower eye margin and a calypter with elongate, tightly crowded setae, which strongly suggests placement within Tachytrechus , near T. flabellifer , the type species of the junior synonym Polymedon . Becker also noted the similarity between Gonioneurum and Polymedon . I consider Gonioneurum to be congeneric with Tachytrechus .

Pollet et al. (2004) considered Stannius’ (1831) treatment of the European species of Dolichopus as a single publication and consequently treated Ammobates Stannius as an incorrect original spelling of Tachytrechus Stannius with Haliday (1851) as the First Reviser (ICZN, Article 24.2). However, that interpretation is incorrect since Stannius’ work was published in three parts, with each part in a different Heft of Oken’s Isis ( Stannius 1831a, 1831b, 1831c). The name Ammobates first appears on page 33 in Heft I ( Stannius 1831a), whereas Tachytrechus does not appear until later, on page 261 of Heft III ( Stannius 1831c). This first mention of the name Tachytrechus on page 261 appears under the description of Dolichopus cupreus , in which Stannius makes the following remark (my comments in square brackets): “This species [i.e. cupreus ] is intermediate between Dolichopus and Tachytrechus erected by me, from which it [i.e. cupreus ] however is sufficiently separated [from Tachytrechus ] by the somewhat shortened but not broadened fore tarsi, through the form of the wings, through the feathered arista, etc.” This remark indicates that Stannius did not consider Dolichopus cupreus to be included in his concept of Tachytrechus . As such, Tachytrechus Stannius, 1831c should be considered a nomen nudum. The valid name for this genus therefore is Tachytrechus Haliday, 1851 , which was proposed as a replacement name for the preoccupied Ammobates Stannius, 1831a .

Material Examined. Tachytrechus alatus (Becker) , [NT]: ɗ lectotype, 1Ψ paralectotype ( ZMHB); 1ɗ paralectotype, 2Ψ paralectotypes ( STMD); Tachytrechus albonotatus (Loew) , [NE, NT]: 4ɗ, 2Ψ ( CAS); Tachytrechus aldrichi (Van Duzee) , [NT]: 1ɗ paratype, 1Ψ paratype ( USNM); 1ɗ paratype, 1Ψ paratype ( CAS); Tachytrechus alternatus (Curran) , [AF]: 3ɗ, 2Ψ ( BMNH); 1ɗ ( ISNB); Tachytrechus ammobates (Haliday) , [PA]: 1ɗ, 1Ψ ( CNC); 1ɗ, 1Ψ ( ISNB); Tachytrechus analis (Parent) , [NT]: ɗ holotype ( MNHN); Tachytrechus angulatus (Van Duzee) , [NE]: 3ɗ, 1Ψ ( USNM); Tachytrechus angustipennis Loew , [NE, NT, AU]: 9ɗ, 5Ψ ( CNC); Tachytrechus argentipes Van Duzee , [NT]: 1ɗ paratype ( CAS); Tachytrechus auratus (Aldrich) , [NE]: 3ɗ, 2Ψ ( CAS); Tachytrechus beckeri (Parent) , [NT]: Ψ holotype ( SMTD); 1ɗ, 1Ψ ( MNHN); Tachytrechus binodatus Loew , [NE]: 4ɗ, 4Ψ ( CNC); Tachytrechus bracteatus (Wiedemann) , [AF]: 2ɗ, 1Ψ ( BMNH); 1ɗ, 1Ψ ( ISNB); 1ɗ, 1Ψ ( CAS); Tachytrechus californicus (Harmston & Knowlton) , [NE]: 1ɗ, 1Ψ ( CAS); Tachytrechus calyptopygeus Robinson , [NT]: 3ɗ paratypes, 2Ψ paratypes ( USNM); Tachytrechus canacolli Brooks , [NE]: 1ɗ paratype, 1Ψ paratype ( CAS); Tachytrechus castus (Wheeler) , [NE]: 2ɗ, 1Ψ ( CNC); Tachytrechus costalis (Becker) , [NT]: 2ɗ, 1Ψ ( CAS); Tachytrechus dilaticosta (Van Duzee) , [NE]: 3ɗ, 1Ψ ( CAS); Tachytrechus flabellifer (Osten Sacken) , [NE]: 6ɗ, 3Ψ ( CAS); 1ɗ, 1Ψ ( CNC); Tachytrechus floridensis Aldrich , [NE]: 2ɗ, 1Ψ ( CNC); Tachytrechus fusicornis (Aldrich) , [NT]: 1ɗ syntype, 1Ψ syntype ( USNM); Tachytrechus fusiformis (Becker) , [NT]: 2ɗ, 2Ψ ( CAS); Tachytrechus giganteus (Brooks) , [NT]: ɗ holotype, 1ɗ paratype, 2Ψ paratypes ( USNM); Tachytrechus granditarsis Greene , [NE]: 2ɗ, 2Ψ ( CNC); Tachytrechus greenei Foote, Coulson & Robinson , [NE]: 3ɗ, 1Ψ ( CAS); 1ɗ, 1Ψ ( CNC); Tachytrechus harmstoni Meuffels & Grootaert , [NE]: 1ɗ, 1Ψ ( CAS); Tachytrechus indianus (Harmston & Knowlton) , [NE]: 7ɗ, 4Ψ ( CNC); Tachytrechus intermedius Becker , [NT]: 2ɗ ( CAS); 1ɗ, 1Ψ ( USNM); Tachytrechus keiferi (Van Duzee) , [NE, NT]: 3ɗ, 2Ψ ( CAS); Tachytrechus laevigatus (Becker) , [NT]: 1ɗ syntype, 1Ψ syntype, 1ɗ ( SMTD); 1ɗ syntype, 1Ψ ( MNHN); Tachytrechus laticrus Van Duzee , [NE]: 2ɗ, 2Ψ ( USNM); Tachytrechus longiciliatus (Van Duzee) , [NT]: 2ɗ paratypes ( CAS); Tachytrechus luteicoxa Parent , [AF]: 3ɗ, 3Ψ ( MRAC); Tachytrechus mchughi Harmston , [NE]: 3ɗ, 1Ψ ( CAS); Tachytrechus moechus Loew , [NE]: 2ɗ, 2Ψ ( CNC); 2ɗ, 2Ψ ( USNM); Tachytrechus nigrifemoratus (Van Duzee) , [NE]: 4ɗ, 2Ψ ( CAS); Tachytrechus nigripes (Aldrich) , [NT]: 1ɗ syntype, 3ɗ, 4Ψ ( USNM); Tachytrechus nimus (Aldrich) , [NE, NT]: 5ɗ, 2Ψ ( CAS); Tachytrechus notatus (Stannius) , [PA]: 1ɗ, 1Ψ ( CNC); 1ɗ, 1Ψ ( BMNH); 1ɗ ( CAS); Tachytrechus olympiae (Aldrich) , [NE]: 2ɗ, 2Ψ ( CAS); Tachytrechus parvicauda (Van Duzee) , [NT]: 1ɗ ( CAS); Tachytrechus planifacies Robinson , [NT]: 2ɗ syntypes, 2Ψ syntypes ( USNM); Tachytrechus ripicola Loew , [PA]: 2ɗ, 2Ψ ( USNM); Tachytrechus sanus Osten Sacken , [NE]: 2ɗ, 1Ψ ( CNC); Tachytrechus seriatus Robinson , [NT]: 2ɗ paratypes, 2Ψ paratypes ( USNM); Tachytrechus simulatus Greene , [NE]: 3ɗ, 1Ψ ( CAS); Tachytrechus subcostatus (Van Duzee) , [NT]: 1ɗ paratype, 1Ψ paratype ( CAS); Tachytrechus tenuiseta Greene , [NE]: 1ɗ, 1Ψ ( CNC); Tachytrechus tessellatus (Macquart) , [PA, AF, OR, AU]: 3ɗ, 3Ψ ( CNC); 1ɗ, 1Ψ (LEM); 1ɗ, 1Ψ ( USNM); 1ɗ ( CAS); Tachytrechus transversus (Van Duzee) , [NT]: ɗ holotype; 3Ψ paratypes ( USNM); Tachytrechus utahensis Harmston & Knowlton , [NE]: 1ɗ, 1Ψ ( CAS); Tachytrechus vanduzeei Robinson , [NT]: 1ɗ ( USNM); Tachytrechus vorax Loew , [NE]: 5ɗ, 5Ψ ( CNC).

Figures

FIGURE 33. Tachytrechus notatus and T. angustipennis: (A) T. notatus, male genitalia, left lateral view (external); (B) T. notatus, male genitalia, left lateral view (internal); (C) T. notatus, male genitalia, ventral view (postgonite, surstylus and cerci not shown); (D) T. angustipennis, male genitalia, postgonite dorsal view; (E) T. angustipennis, male genitalia, postgonite lateral view; (F) T. notatus, female genitalia, dorsal view; (G) T. notatus, female genitalia, left lateral view.

FIGURE 34. Tachytrechus moechus: (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 35. Tachytrechus laevigatus: (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 36. Tachytrechus beckeri: (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.