Revision of the South American species of Austrothaumalea Tonnoir (Diptera Thaumaleidae) Author Pivar, Robert J. 0000-0003-2642-0524 The University of Tennessee, Department of Entomology and Plant Pathology, 2505 E. J. Chapman Drive, 370 Plant Biotechnology Building, Knoxville, Tennessee, 37996, U. S. A. & robertjpivar @ gmail. com; https: // orcid. org / 0000 - 0003 - 2642 - 0524 robertjpivar@gmail.com Author Sinclair, Bradley J. 0000-0001-6413-1606 Canadian National Collection of Insects and Canadian Food Inspection Agency, K. W. Neatby Building, C. E. F., 960 Carling Avenue, Ottawa, Ontario, Canada K 1 A 0 C 6. bradley. sinclair @ canada. ca; https: // orcid. org / 0000 - 0001 - 6413 - 1606 bradley.sinclair@canada.ca Author Moulton, John K. 0000-0001-8760-3274 The University of Tennessee, Department of Entomology and Plant Pathology, 2505 E. J. Chapman Drive, 370 Plant Biotechnology Building, Knoxville, Tennessee, 37996, U. S. A. & jmoulton @ utk. edu; https: // orcid. org / 0000 - 0001 - 8760 - 3274 text Zootaxa 2020 2020-09-24 4853 4 509 526 journal article 8413 10.11646/zootaxa.4853.4.2 0ffa72e0-c3b8-4c3c-8b64-a39dab962daa 1175-5326 4411060 948793DC-3873-4C14-8239-E30ED790E56A Austrothaumalea chilensis Edwards ( Figs 3C , 4B , 5B , 6B , 7B , 8 , 9A ) Austrothaumalea chilensis Edwards, 1930: 111 . Other references: Stuardo, 1946: 42 (catalogue); Stone, 1966: 1 (catalogue); Arnaud, 1977: 284 (distribution); Theischinger, 1986: 316 (phylogenetic discussion); Sinclair, 2008b: 11 ( capricornis species group). Type material examined. Holotype : ♂ , minuten pinned with abdomen mounted in resin, labelled: “Ancud./ 17–19.xii.1926 .”; “ Austrothaumalea / chilensis Edw./ F.W. Edwards / det. 1930.”; “ S. Chile :/ Chiloe I./ F. & M. Edwards. / B.M. 1927 – 63.”; “HOLO-/ TYPE [white label with red margin]”; “ NHMUK010210688 ” ( BMNH ) . Allotype : ♀ , same label data as holotype ( BMNH ) . Paratypes : CHILE : Region X ( Los Lagos ): Casa Pangue ( 1♂ , BMNH ); Ancud ( 3♂ , 1♀ , BMNH ) . Recognition. The gonocoxal plate with long, lateroapical teeth, and the cruciate paramere are characters that readily distinguish this species. The lateral, cross-like projections on the paramere are located apically, not concealed by the gonocoxal plate and are much shorter than those of A. fredericki . This is also the only known thaumaleid in South American to have the gonocoxal plate secondarily fused to the ventral surface of the hypandrium. Redescription. Male. n = 4. Length 2–2.3 mm . Colouration ( Fig. 3C ). Head dull, dark brown; pronotum and postpronotum brown; postpronotal lobe brown; mesoscutum and pleura brown, somewhat shiny; scutellum and mediotergite brown, shiny; katepisternum dark brown; halter brown, dark at apex of knob; legs pale brown, apices of femora and tarsi darkened; abdomen dark brown; terminalia brown. Head . Eyes above antennae broadly joined, frons above antennae barely exposed. Flagellomeres 1–3 expanded, subquadrate; 1 as long as 2 and 3 combined; flagellomeres 4–10 thin, cylindrical, becoming progressively more elongate. Vertex clothed in golden setae of uniform length, with sparse, long, black orbital setae. Thorax . Pronotal setae longer than scutal setae. Scutum clothed dorsally in short, golden setulae; notopleural, supra-alar and postsutural setae long, black. Pteropleuron bare. Fore- and mid legs with tarsi simple, hind leg with tarsomere 4 bilobed. Wing . Wing length: 2.2–3.0 mm. Lightly infuscate throughout, apex broadly rounded; C and posterior wing margin with fringe of microtrichia; Sc incomplete; R 1 and R 1 (+R 2+3 ) without weakenings or depigmented gaps, with uniseriate row of microtrichia along entire length, remaining veins bare; R flexed into cell br; R 2+3 crossvein strong, situated toward apex of R 1 (+R 2+3 ); bend in R 4+5 well-defined; R 4+5 and M 1 running parallel toward margin; M 1 and M 2 straight; M 4 slightly sinuous; CuA with basal spur shorter than crossvein m-cu. Abdomen . Abdominal sternite 1 narrow, spectacle-shaped; sternite 2 reduced to slender median sclerite, few setae on posterior margin; sternites 3–6 rectangular, weakly sclerotized, setae largely restricted to posterior half; sternite 7 semi-circular, a few setae on posterior margin, weakly sclerotized except for anterior margin, arched slightly into preceding sternite; sternite 8 crescent-shaped, bare, well sclerotized, strongly arched into preceding sternite. Terminalia ( Figs 4B , 5B ). Epandrium elongate-oval from ventral aspect; apical third slightly tapered; posterior margin broad and rounded; lacking pointed posterolateral processes. Hypandrium broad in ventral view, wider than basal width of gonostylus; anterior margin not concave. Gonocoxite broadest basally, inner margin parallel, smooth. Gonostylus shorter than gonocoxite, gently curved throughout, tapered to point. Parameres distally fused, three-quarters length of epandrium, apex cruciform. Gonocoxal plate with well sclerotized base divided into two lateral, sclerotized arms terminating in 2–4 long apical teeth, arranged irregularly; nearly three-quarters length of gonocoxite; inner basal third lightly sclerotized, apical two-thirds membranous; secondarily fused to ventral surface of hypandrium. Cercus weakly sclerotized, situated along midline of epandrium. Female. n = 2. Similar to male except as follows: Length : 1.8–2.1 mm . Abdomen : Tergites 8–9 noticeably more sclerotized than preceding segments; only anterior margin of sternite 7 well-sclerotized. Terminalia ( Figs 6B , 7B ): Hypogynial valve slightly shorter than tergite 9; posterior margin with rounded shallow cleft in ventral view; densely setose. Tergite 9 rectangular in lateral view, wider than tergite 8, posterodorsal corner projected posteriorly. Sternite 9 (genital fork) connected anteriorly, then divided into two thin arms, projecting laterally before cleft of hypogynial valve and expanded into rounded sclerite; lateral arms extended slightly beyond hypogynial valve, arms nearly meeting along midline; spectacle-shaped in lateral view, with anterior portion circular and posterior portion trapezoidal. Cercus rounded, projected posteriorly; bearing numerous setae. Spermathecal ducts not observed; spermathecal pump located in middle of lateral arm, short, thickened. Immature Stages. Unknown. Additional Material Examined. CHILE : Region RM ( Santiago ) : El Canelo , 10-I-1967 , 33°37′S 71°35′W , 950 m , E.I. Schlinger ( 1♂ , CAS ) . Region IX ( Araucanía ): Rte. 71, 15-XII-2016 , 38°13′20.3″S 71°44′41.1″W , elev. 1047 m , seep, J.K. Moulton & R . J. Pivar ( 1♂ ); Region X ( Los Lagos ): Isla Chiloé , Ancud , XII-1926 , R & E Shannon ( 1♂ (USNMENT01115810), 2♀ (USNMENT01115808-09) USNM ) . Distribution. Known from the Andes of central Chile , south to Isla Chiloé along the Chilean Coastal Range ( Figs 8 , 9A ). Remarks. We visited the locality based on GPS coordinates given on the Schlinger specimen label and arrived at a site near the coastal town of San Antonio, where no appropriate thaumaleid habitat was visible. We also visited a site in the Andes, in a small town named ‘El Canelo’, which has a number of mountain creeks with suitable habitat, although the creek, Estero el Canelo ( 33°34′31″S 70°26′47″W ), was fenced off and inaccessible for collecting attempts.