Liriomyza trixivora, Lonsdale, 2011

Lonsdale, Owen, 2011, The Liriomyza (Agromyzidae: Schizophora: Diptera) of California 2850, Zootaxa 2850 (1), pp. 1-123 : 108-110

Liriomyza trixivora spec. nov.

Figs 240–243

Liriomyza sp. Goeden & Ricker 1989: 329.

Wing length 1.6–1.7mm (♂), 1.8mm (♀). Length of ultimate section of vein CuA 1 divided by penultimate section: 2.6–3.6; vein dm-cu vestigial in one male. Eye height divided by gena height: 5.6–6.5. Scutum shining. First flagellomere relatively large and quadrate.

Chaetotaxy: Two ori, two ors. Acrostichal setulae in four rows.

Colouration: Calypter margin and hairs grey. Head light yellow with clypeus light brown (yellow medially) and back of head and ocellar triangle dark brown; dorsal margin of first flagellomere infuscated to distinctly brown anterior to base of arista, but in females this pigment often expanded to dorsal half of segment on outer face and to venter on inner face (excluding yellow basal margin); posterolateral corner of frons dark brown to base of outer vertical bristle and light brown to base of inner vertical. Scutum with complete lateral yellow stripe; katatergite yellow; anatergite brown lateral to scutellum with dorsum yellow and dark brown below scutellum. Anepisternum with small faint anteroventral spot that is sometimes enlarged; anepimeron with small brown anterior stripe and sometimes faint brown marginal spot posteriorly; meron brown on ventral 2/3; katepisternum with large brown spot on ventral 2/3. Legs yellow with tarsi and fore and mid tibiae with very light brown tint with distal three tarsomeres slightly darker; hind tibia brown with dorsum darker. Abdomen brown with lateral margin thinly yellow.

Genitalia: Figs 240–243 . Surstylus with two or three dark spines. Paraphallus band-like with apex pointed. Hypophallus short with basal stem dark and apical hairs fused to a point. Mesophallus slightly longer than wide and separate from distiphallus; mesophallus and distiphallus with ventral longitudinal suture. Distiphallus pale and bell-shaped with length slightly greater than width and with nearly indistinct inner subapical fringe of hairs. Ejaculatory apodeme weakly-pigmented and gracile, with stem and pileus ejaculatorius thin, and with blade small and triangular.

Variation: Male from Palm Desert differs as follows: wing length 2.0mm; length of ultimate section of vein CuA 1 divided by penultimate section 3.1; eye height divided by gena height 6.0; first flagellomere ovate, unenlarged and entirely yellow; pigment on legs not as distinct/contrasting.

Etymology. The specific name indicates the host plant.

Host. Asteraceae — Trixis californica . The last instar larve pupates inside of the leaf.

Range. USA. California [Imperial, Riverside, San Bernardino, San Diego].

Type material. Holotype, USA. California: San Bernardino Co., Sheephole Mtn. [at Sheephole Pass], 14.iii.1984, R. D. Goeden & D.W. Ricker, insectary reared on Trixis californica Kell. , 34°14'49"N, 115°43'03"W, URCR ENT 235263 (1♂ [with puparium], UCR) ; Paratypes, USA. California: Imperial Co., Indian Well, 8.i.1985, R . D. Goeden & D.W. Ricker, insectary reared on Trixis californica Kell., URCR ENT 235061 (1♀ [with puparium], UCR) , Riverside Co., Desert Center, 14.iii.1984, R . D. Goeden & D.W. Ricker, insectary reared on Trixis californica Kell., URCR ENT 235274 (1♂ [with puparium], UCR; 1♂ [with puparium], USNM), Graham Pass , R . D. Goeden & D.W. Ricker, insectary reared on Trixis californica Kell. , 21.iii.1984 (1♀, CSCA), 12.iii.1986, URCR ENT 235275 (1♀, UCR) , Pines to Palms Hwy., 11.i.1984, R . D. Goeden & D.W. Ricker, insectary reared on Trixis californica Kell. (1♀ [with puparium], CASC), Chino Canyon , 29.ii.1984, R . D. Goeden & D.W. Ricker, insectary reared on Trixis californica Kell., URCR ENT 235276 (1♀ [with puparium], UCR), 3.5mi S Palm Desert (P.L. Boyd Des. Res. Center) Malaise trap, 2–5.vi.1978 (1♂, CSCA) , San Diego Co., Yagui Pass, 11.i.1984, R . D. Goeden & D.W. Ricker, insectary reared on Trixis californica Kell., URCR ENT 235278 (1♀ [with puparium], UCR) .

Comments. Liriomyza trixivora was discussed as “ Liriomyza sp. ” in Goeden & Ricker (1989), which was commonly collected from the leaves of Trixis californica across southern California. Their valuable collected material forms the bulk of the type series. The only agromyzid previously known from Trixis is an unknown species from Argentina ( Spencer, 1990) .

While the phallus of Liriomyza trixivora is relatively nondescript, similar taxa (eg. L. cannabis Hendel, L. asterivora Sasakawa, L. fasciola (Meigen) , L. tricornis , L. schlingeri , L. temperata Spencer and L. venturensis ) can be distinguished by a small, ovate and entirely yellow first flagellomere, slightly different dimensions of the distiphallus, a broadly rounded ejaculatory apodeme, and aside from L. tricornis , only a single spine on the surstylus. The two spines on the surstylus of L. tricornis differ from those of L. trixivora , however, in that they emerge from a membranous basal region, not subapically. The phallus of L. eupatorii is also relatively similar, but this is a larger species with a broader, basally truncated distiphallus.

Aside from Liriomyza trixivora , the remaining North American species with nondescript male terminalia listed above can be quite difficult to tell apart. Liriomyza temperata is the only eastern species (North Carolina), and it apparently differs in having a slightly larger wing (2.3–2.5mm), gena (eye approximately three times higher than gena) and cell dm (length of ultimate section of vein CuA 1 slightly more than twice length of penultimate section), although Spencer’s measurements have been known to vary considerably in accuracy and should be verified. Liriomyza tricornis is the only one of these species with three pairs of fronto-orbitals (not four), brown streaking on the femora, the inner vertical bristle touching the brown posterolateral region of the frons, and the derived surstylus mentioned above. Liriomyza schlingeri differs from L. venturensis in having a smaller cell dm (length of ultimate section of vein CuA 1 2.1–2.6 times length of penultimate section, not 4.1), the eye is only 4.2–5.5 times higher than the gena (not 3.6) and the base of the katepisternal bristle touches the brown ventral marking (not entirely surrounded by yellow).

Figures

FIGURES 240–244. Figs 240–243: Liriomyza trixivora spec. nov., male genitalia; 240: phallus, ventral; 241: phallus, left lateral; 242: external components, ventral; 243: ejaculatory apodeme. Fig. 244: L. pictella (Thompson), ejaculatory apodeme, male phallus ventral and left lateral.