Trichodischia soror Bigot, 1885

Alvarez-Garcia, Deivys M. & Santis, Marcelo Domingos de, 2021, Redescription of the Neotropical species Trichodischia soror Bigot, 1885 (Diptera: Tachinidae), with a new generic synonymy, Papéis Avulsos de Zoologia (Pap. Avulsos Zool., S. Paulo) 61, pp. 1-7 : 3-6

Trichodischia soror Bigot, 1885

( Figs. 1-3 )

Trichodischia soror Bigot, 1885 : xlvi (description of male). Holotype male (NHMUK), examined (in good condition).

Type locality: Argentina, Buenos Aires.

References: Brauer (1898: 499, redescription, taxonomic notes); Cortés (1944: 49, T. soror as junior synonymous of T. caerulea ); Parker (1953: 53, cited as T. caerulea , host record; 67, drawing of cephaloskeleton of first instar larva and puparium); Parker et al. (1953: 18, cited as T. caerulea , host record); Blanchard (1963: 186, cited as T. caerulea , host record); Cortés (1969: 97, taxonomic notes and revalidation of T. soror ); Guimarães (1971: 100, catalogue); Cortés (1974: 35, taxonomic notes; 37, discussion on host records); Guimarães (1977: 76, 106, cited as T. caerulea , host catalogue); Cortés (1980, 105, distributional records); Tschorsnig (1985: 100, description of male terminalia of Dexiinae ); González (1992: 179, populations aspect of tachinids from the National reserve Rio Clarillo – Chile); Virla et al. (1999: 10, host notes); Molina-Ochoa et al. (2003: 269, host notes); Evenhuis & Pont (2004: 60, taxonomic note); O’Hara et al. (2020: 176, world checklist of tachinids).

Additional material examined BRAZIL: Santa Catarina: Nova Teutônia, 1 ♂ [dissected],

ix.1967, F. Plaumann Leg. ( MZSP) ; Nova Teutônia, 1 ♀ [dissected], x.1967, F. Plaumann Leg. ( MZSP). Chile: Cautín: Villarica , 1 ♀, 18.xii.1966, Irwin Leg. ( MZSP) ; Concepción: Parque Botánico Hualpen , 1 ♂ [dissected], ii.1970, T. Cekalovic Leg. ( MNRJ) ; Los Lagos: Osorno , 1 ♂, 24.xi.1968, R. Cortés Leg. ( MZSP) ; Malleco: Angol , 1 ♀, xi.1972, T. Cekalovic Leg. ( MZSP) .

Distribution

Argentina (Buenos Aires), Brazil (Santa Catarina), Chile (Valparaíso, Cautín, Concepción, Los Lagos, and Malleco), Uruguay (Montevideo).

Redescription of male

Coloration ( Fig. 1 ): Body entirely dark brown to blackish, with gray pruinosity. Palpus yellow to yellowish-brown. Tibiae sometimes slightly yellowish. Wings sub-hyaline, slightly brown, with brown veins; tegula black and basicosta brown. Calypters whitish.

Head ( Fig. 1 C-E): Dichoptic. Eyes hairy. Fronto-orbital plate setulose. Ocellar tubercle with a pair of strong lateroclinate ocellar setae. Row of 6-8 inclinate frontal setae, arising at level of pedicel. One lateroclinate orbital seta. Inner vertical setae erect. Outer vertical setae lateroclinate. A pair of postocellar setae. One paravertical seta. Postcranium globose, with black hairs. Parafacial setulose along its whole extension. Strong vibrissae surrounded by small setulae. Palpus slender and setulose, about half length of prementum. Lower facial margin straight, not visible in lateral view. Antenna inserted to level of middle of eyes; arista micro-pubescent and with basal third slightly thickened.

Thorax ( Fig. 1 A-D): Acrostichal setae 1+1, first and second pair absent. Dorsocentral setae 3+3. Intra-alar setae 1+3. Supra-alar setae 1+3. Postpronotal setae 4, three basal and one anterior. Notopleural setae 2. Postalar setae 2. Proepisternal seta 1, accompanied by 1-2 setulae. Proepimeral seta 1, accompanied by two setulae. Katepisternal setae 3. Anepisternal setae 5-6. Anepimeral seta 1, extending to the posterior margin of upper calypter. Meral setae 4-6. Prosternum bare. Scutellum scattered with setulae, with decussate apical scutellar setae, divergent subapical scutellar and lateral scutellar setae, and straight basal scutellar setae. Wing: A pair of costal spines, one short and other long. Vein C ending just before wing apex. Vein M₁ ending at wing margin, before the end of vein C. Bend of vein M rounded. Cell r₄₊₅ open, length of opening shorter than crossvein r-m. Crossvein dm-cu sinuose.Vein R₄₊₅ dorsally setose to crossvein r-m. Legs: Hind femur with a ventral patch of long and hairslike setulae.

Abdomen ( Fig. 1 A-B): Globose. Mid dorsal depression of syntergite 1+2 extending to the middle of segment. Syntergite 1+2 with concave dorsal margin and one lateral marginal seta. Tergite 3 with one lateral marginal seta, a pair of median marginal setae, and a pair of discal setae. Tergite 4 with a pair of median discal setae, and a row of dorsolateral marginal setae. Tergite 5 with a row of dorsolateral discal setae, and a row of marginal setae. Terminalia ( Fig. 2 A-F). Sternite 5 with a transversal membranous band, lobes well developed and setulose, and sensilla trichodea absent. Sternite 6 asymmetrical. Tergite 6 undivided, posteriorly setulose, band-shaped gradually tapering sideways, attached to syntergosternite 7+8 by a narrow membrane. Syntergosternite 7+8 broad and setulose. Spiracle 6 both on the membrane, and spiracle 7 both on anterior margin of syntergosternite 7+8. Ejaculatory apodeme hand-fan shaped, with narrow basal plate and wide process. Epandrium setulose, closed dorsally; posterior epandrial process small and moderately acute; anterior epandrial process triangle-shaped with posterior margin curved; lower lateral margin with developed lobe partially covering the surstylus. Hypandrium with long, up curved and arms not fused; hypandrial apodeme well developed, longer than width, and slightly bowl-shaped. Cerci not fused, tapering distally, with straight inner margins and oblique outer margins in posterior view; beak-shaped distal end in lateral view. Surstylus broad, subtriangular with rounded end in lateral view; medially widened and with hook-shaped distal end in posterior view. Phallapodeme slightly arched, extending a little beyond the hypandrial apodeme; phallic guide short. Basiphallus robust and tube-shaped, projecting into a claw-shaped epiphallus. Distiphallus with ventral sclerite longer than dorsal sclerite; ventral sclerite with distal end dorsally fused; membranous region connecting the distal ends of dorsal sclerite and ventral sclerite. Pregonites subrectangular in lateral view, not fused with each other, basal region slightly expanded and fused with medial plate of hypandrium. Postgonites not fused, narrow and claw-shaped, located dorsolaterally to basiphallus, extending almost until apex of distiphallus.

Female ( Figs. 3 A-F)

Similar to male, but with a pair of proclinate orbital setae, and hind femur without the ventral patch of hairslike setulae.

Figures

Figure 1. Trichodischia soror (♂, Osorno, Chile, MZSP).(A) Dorsal habitus. (B) Lateral habitus.(C) Head, dorsal view. (D) Head, frontal view.(E) Head, lateral view. (F) Hind femur with ventral patchof hairs-like setulae.Scale bars:A,B = 2 mm,C, F = 0.5 mm,D,E = 1 mm.

Figure 2. Male terminaliaof Trichodischiasoror.(A) Epandrium,cerci and surstylus,lateral view.(B) Epandrium,cerci and surstylus,posterior view.(C) Hypandrium, phallapodeme,basiphallus,epiphallus,distiphallus,pregonite,and postgonite lateral view.(D)Sternite 5,ventral view.(E) Sternite 6,posterior view.(F)Ejaculatory apodeme.Scale bars:A-E =0.25mm,F =0.1mm.Abbreviations:basph =basiphallus;cerc =cercus;distph =distiphallus;ejapod =ejaculatory apodeme;epiph= epiphallus;epand = epandrium;hypd = hypandrium;pgt = postgonite;phapod= phallapodeme;pregt = pregonite;st = sternite;sur = surstylus.

Figure 3. Trichodischia soror (♀, Villarica,Chile,MZSP).(A) Dorsal habitus.(B) Detail of abdomen indorsal view.(C) Lateral habitus.(D) Head,dorsal view.(E) Head, frontal view.(F) Head,lateral view.Scale bars:A,C = 2 mm,B,D = 1 mm,E,F = 1 mm.