Tritoxa californica, Sinclair & Macleod & Wheeler, 2021

Sinclair, Bradley J., Macleod, Alyssa M. & Wheeler, Terry A., 2021, Revision of the Nearctic genus Tritoxa Loew (Diptera: Ulidiidae), Zootaxa 4920 (3), pp. 359-379 : 361-362

Tritoxa californica sp. nov.

( Figs 6 , 14, 15 , 24 )

urn:lsid:zoobank.org:act:0350D4DB-7407-4C19-941A-31B9951299EB

Type material. HOLOTYPE ♂, labelled: “ CALIF: Plumas Co. / Little Long Valley / Creek [39°52′06″N 120°42′08″W], 6000′ 6 mi. E./ Spring Garden/ VIII-4-10-1977 ”; “ Malaise Trap / 8A-6P/ M. Wasbauer / Collector”; “ HOLOTYPE / Tritoxa / californica Sinclair ,/ MacLeod & Wheeler” ( CSCA) . PARATYPES: USA. California: El Dorado Co., Pollack Pines [38°45′41″N 120°35′12″W], 2.ix.1986, Jackson trap, peach, D. Bolster (1♂, CSCA) ; Nipa Co., Angwin , 38.575°N 122.453°W, 17.ix.2008, McPhail trap, T. Samansky (1♂, 1♀, CSCA) ; Same data as holotype (1♂, 2♀, CSCA) ; Santa Cruz Co., Big Basin SP [37°10′21″N 122°13′21″W], 13.ix.1966, E.L. Sleeper (1♂, CAS) ; Trinity Co. [40.66°N 123.12°W], 13.vi.1934 (1♂, CAS) ; Tuolumne Co., 2.7 mi E Smoky Jack [37°49′3.72″N 119°42′45.61″W], Summer 1962, Frick trap on Prunus emarginata, D.P. Allen (1♂, CSCA) .

Possible additional material. USA. California: El Dorado Co., Placerville [38°43′47″N 120°47′55″W] , 26.vi.1953, P.H. Arnaud (1♂, USNM) [genitalia lost]; Sagehen Ck Field Stn., 15 km N Truckee , 39°25.89′N 120°14.61′W , 16.viii.1999, J. Savage (1♀, LEM); Nevada Co., Sagehen Ck [39°25′57″N 120°14′13″W] , 2.vii.1968, R. W. Pinger (1♀, USNM) .

Diagnosis. This species has the general appearance of Tritoxa cuneata , but is distinguished by the short, oblique discal hyaline crossband not extending beyond level of crossvein r-m in cell dm, inner surstylus with tight cluster of 4–5 thick prensisetae and phallus is shorter, with two loops.

Description. Entirely yellowish brown to brown, abdomen darker brown bands. Head: ocellar triangle dark brown to black, microtrichose; frons yellowish brown to brown; parafrontal silvery microtrichia stripe very narrow, limited to extreme margin of eye, continuous with very narrow microtrichose parafacial; gena slightly darker brown below narrowest part of lower eye margin; postocular microtrichia slightly wider than parafrontal microtrichose stripe in lateral view, extending from base to middle of eye; face concolourous with face laterally, slightly paler medially; supracervical setulae very pale. Antenna with postpedicel greyish brown, yellowish brown on inner and medially surfaces. Proboscis with yellowish brown palpus. Thorax: yellowish brown; scutum mostly thinly microtrichose without pair of vittae; lateral margin of scutum and postpronotal lobe broadly shiny; scutellum concolourous with scutum; mediotergite without distinct stripe; pleura shiny, anepisternum and katepisternum lightly clothed in whitish microtrichia when viewed obliquely; whitish microtrichia above fore coxa; 2 anepisternal setae. Wing ( Fig. 6 ) entirely brown, slightly tapered apically, with 3 hyaline crossbands; some faded or paler regions between bands; costal cell without hyaline band at humeral break, with narrow hyaline band at extreme apex of cell in line with discal hyaline crossband; oblique subbasal hyaline crossband very short, extending to basal fifth of cell dm; discal hyaline crossband short, continuous from R 1, reaching posterior margin of cell dm, not extending beyond level of crossvein r-m in cell dm; subapical hyaline crossband nearly straight, anterior end not extending proximal to crossvein r-m; crossvein dm-m straight to slightly arched; anal lobe developed; calypter with white margin. Abdomen: yellowish brown. Male terminalia ( Figs 14, 15 ): inner surstylus with tight cluster of 4–5 thick prensisetae, inner margin concave; outer surstylus slender, slightly tapered and arched, slightly longer than length of inner surstylus, with narrow apex ( Fig. 10 ); subepandrial sclerite with strong dark setae. Cercus with short setae; apical margin slightly pointed. Phallus short, with 2 loops.

Distribution. This species is known exclusively from northern California ( Fig. 24 ).

Remarks. See comments under T. cuneata .

Figures

FIGURES 6–13. Wings of Tritoxa species. 6. T. californica sp. nov.; 7. T. cuneata; 8. T. decipiens sp. nov.; 9. T. flexa; 10. T. incurva; 11. T. pollinosa; 12. T. ra; 13. Tritoxa sp. Abbreviations: d bd—discal band; dm—discal medial cell; dm-m—discal medial crossvein; r-m—radial medial crossvein; sbap bd—subapical band; sbb bd—subbasal band.

FIGURES 14–17. Male terminalia of Tritoxa species. 14. T. californica sp. nov., posterior view; 15. T. californica, oblique lateral view; 16. T. cuneata, posterior view; 17. T. decipiens sp. nov., posterior view. Abbreviations: cerc—cercus; epand—epandrium; ph—phallus; prens—prensiseta; sur—surstylus.

FIGURES 24–26. Distribution of Tritoxa species. 24. T. californica sp. nov. (incl. unconfirmed records (red open circles)) and Tritoxa sp.; 25. T. decipiens sp. nov.; 26. T. cuneata and T. flexa.