Zelia spectabilis (Wulp, 1891)

(Fig. 18)

Melaleuca spectabilis Wulp, 1891b: 248 . Type locality. Mexico Guerrero, Xucumanatlan.

References: Townsend (1918: 182, synonymy with Dexia gracilis Wiedemann [ = vertebrata Say]); Aldrich (1929: 2, possible synonymy with Z. vertebrata); Townsend (1931: 97, synonymy with Z. vertebrata); Townsend (1939: 88, removed from synonymy with Z. vertebrata); Guimarães (1971: 101, catalogue); O’Hara et al. (2020: 52, World checklist of Tachinidae).

Type material examined. Holotype female:“Holo-/type’‘ ♀ ”; “ Xucumanatlan,/ Guerrero,/ 700 ft,/ July.H.H.Smith”; “B.C.A. Dipt. II/ Melaleuca /spectabilis,/ v.d.W.; “ Central America. / Pres. By/ F. D. Godman. / O. Salvin. /1903- 172.”; “ NHMUK 013933625 ”.

Diagnosis. Eye bare. Facial carina undeveloped. Head entirely silvery pruinose. Postpedicel blackish, but about dorsal 1/6 brownish-tawny. Palpus slightly clavate. Katepisternum with 2+1 setae. Wing hyaline. Abdomen similar to Z. limbata, with tergite 5 reddish-brown but anterior 1/3 silver pruinose, but if differs by tergites 3 and 4 silver to grayish pruinose, but distal 1/4 brownish black, with mid region of tergite with an ample spot of brownish black color. Abdominal tergites 3 and 4 with one small and weak pair of discal setae.

Redescription. Female. Body length: 9.5 mm.

Coloration (Fig. 18). Frontal vitta and ocellar triangle dark brown to black. Head with silvery pruinosity, but gena slightly brownish black. Occiput with black setulae. Scape dark brown, pedicel tawny yellow. Postpedicel brownish black, but proximal 1/6 tawny yellow. Palpus and labella orange to yellow-tawny. Thorax mainly silver pruinosity; scutum with four dark vittae, in prescutum the two inner vittae are thinner than the outer, in postscutum, the inner vittae is half the length of the outer, neither reaching the scutellum. Scutellum silver pruinose, but 1/4 light brown posteriorly. Wing hyaline, slightly light brown along the veins. Calypter hyaline. Halter yellow-tawny. Posterior spiracle brownish black. Legs brown to tawny, but silver pruinosity on coxae and front femur; and only ventrally on mid and hind femora; tarsi darker. Claws brown, pulvilli yellow. Abdomen brownish black with grayish silver pruinosity on tergites 3 to 5. Syntergite 1+2 brownish black, but anterolateral area silvery pruinose. Tergites 3 and 4 silver to grayish pruinose, but distal 1/4 brownish black, with mid region of tergite with an ampler spot of brownish black. Tergite 5 reddish-brown but anterior 1/3 silver pruinose.

Head (Fig. 18). Vertex about 0.25x head width in dorsal view. Frontal vitta, in the narrowest point, 1.2x the width of ocellar triangle. Fronto-orbital plate with 12–13 pairs of proclinate setae; about the same width of frontal vitta and parafacial. Fronto-orbital plate with 2 proclinate and 1 reclinate setae. Width of parafacial measured between inner margin of compound eye and antennal insertion is 0.4x the width of gena. Postpedicel slender, 2.2x the combined length of scape and pedicel; longer than the dorsal, longest cilia ca. 7x basal width of arista. Facial ridge with two to three setulae on lower third. Lower facial margin not protruding, invisible in profile. Eye about 0.5x the head height. Gena about 0.58x eye height. Vibrissa missing, but cicatrix inserted above lower facial margin. Labella well-developed.

Thorax (Fig. 18A, C). Acrostichals 2+3. Dorsocentral 4+3. Intra-alar 1+1; intra-postalar absent. Supra-alar 1+3, first postsutural weak. Postpronotal lobe with three setae, two forming an anterior row and one posterior. Anepisternum with six strong setae and with one upward directed setulae anteriorly. Scutellum with one basal, one lateral, one apical and one discal pairs of setae. Katepisternum with 2+1 setae. Anepimeron with various equally long setae. Postalar callus with 3 setae. Legs. Fore coxa with many setae anteriorly; fore femur with dorsal and posteroventral rows of setae; fore tibia with 1 posteroventral seta on median third, 3 preapicals, 2 anterior and 1 posteroventral setae. Mid femur with 3 anterodorsal on apical third, 4 preapicals, 2 anterodorsals and 2 posteroventral setae; mid tibia with 1 anteroventral seta on and 1 anterodorsal on median third. Hind femur with three anteroventral setae on basal half and three ventral setae on basal half and with row of anterodorsal setae; hind tibia with 3 anterodorsal and 1 posterodorsal on median third, 1 posteroventral seta on distal third, 3 preapicals on anterodorsal surface.

Abdomen (Fig. 18A, C). Syntergite 1+2 with a pair of lateral marginal setae. Tergites 3 and 4 with one discal, one median marginal seta and one lateral marginal pair of setae. Tergite 5 with one pair of discal setae and one row of marginal setae. Terminalia. Not dissected, only female holotype was available.

Male. Unknown.

Biology. Unknown.

Distribution. Mexico (Guerrero, Xucumanatlán).

Remarks. The validity of Z. spectabilis was changed by some authors since its original description. Townsend (1918: 182) was the first to question the validity of this species by putting Z. spectabilis in synonymy with Dexia gracilis Wiedemann (= Z. vertebrata). Aldrich (1929: 2) confirmed this view, stating that Z. spectabilis may be the female of Zelia vertebrata . A couple of years later, Townsend (1931: 97), without giving any reason, repeated the proposition that Z. spectabilis is a synonym of Z. vertebrata . However, in a later work, Townsend (1939: 88) changed his mind and preferred to consider this species as valid and “congeneric” with the genus Zelia . Herein, Z. spectabilis is considered as valid and different from Z. vertebrata and other Zelia species, as keyed and diagnosed above.