Liriomyza graminaceae Spencer

Lonsdale, Owen, 2011, The Liriomyza (Agromyzidae: Schizophora: Diptera) of California 2850, Zootaxa 2850 (1), pp. 1-123 : 52-54

Liriomyza graminaceae Spencer

Figs 112–115

Liriomyza graminaceae Spencer 1981: 237 . Spencer & Steyskal 1986: 132.

Wing length 2.2–2.4mm (♂), 2.5–2.7mm (♀). Length of ultimate section of vein CuA 1 divided by penultimate section: 1.4–2.1. Eye height divided by gena height: 4.1–6.2. Scutum subshining. Orbital plate projecting anteriorly.

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

Colouration: Calypter margin and hairs brown. Head yellow with brownish stripe along ventral margin of gena, and ocellar tubercle, clypeus, back of head and posterolateral region of frons to base of inner vertical bristle (excluding yellowish spot at base of outer vertical) dark brown. Scutum dark with complete yellow lateral stripe; katatergite brown; anatergite brown with posterodorsal corner lateral to scutellum yellow and region below scutellum darker. Pleuron dark with dorsal 2/5 of anepisternum yellow (with deep triangular emargination at midpoint), dorsal margin of meron yellow, and dorsal margin of katepisternum yellow to base of bristle. Base of fore coxa, basal half of mid coxa and all of hind coxa dark brown; femora with brown base, fore femur brown basally on outer half and on dorsal 2/3, mid femur brown basally on outer 1/3 and dorsal half (reduced to thin stripes in holotype), and hind femur dark with distal 1/3 yellow; fore tarsus brown, fore tibia brown with base yellow, but sometimes yellow with brown mottling; mid and hind tibiae and tarsus dark brown with base of tibiae sometimes yellow. Abdominal tergites brown with posterior margin thinly yellow and lateral margin broadly yellow, particularly on anterior tergites, as in L. septentrionalis .

Genitalia: Figs 112–115 . Surstylus vestigial, and surstylus and epandrium without spines. Basiphallus sclerotized dorsally, with one pair of anterolateral processes and single membranous lobe on left distal margin. Swollen region of ejaculatory duct dorsally flat. Paraphallus absent. Hypophallus long-haired and narrowly joined to base of distiphallus. Mesophallus indistinct. Distiphallus pipe-shaped, with narrow, curved basal section that expands to apex, and small cup-like distal section enclosing long, thin, dark inner processes and inner-marginal spines. Ejaculatory apodeme with heavily-sclerotized pileus ejaculatorius, with dark process extending from each end; stem short, dark and stout; blade broad and subovate, becoming paler apically with dark marginal band and longitudinal striations.

Hosts. Unknown; likely Poaceae .

Range. USA. California [Alameda, Contra Costa*, El Dorado, Fresno, Inyo, Mono, Nevada, Placer , San Diego, San Luis Obispo*, San Mateo, Santa Clara*, Santa Cruz, Tulare], Colorado.

Type material. Holotype, USA. California: San Diego Co., La Mesa, 15.x.1958, P. Rude (1♂, CASC) ; Paratypes examined, USA. California: Alameda Co., Albany , 21.vi.1971, C.A. Belmont (1♀, EMEC) , Fresno Co., Hooper Cr. at road to gauging station on S Pk., San Joaquin River , 7200’, 30.viii.1971, H. Leech (1♂, CASC) , Mono Co., Alt. 7200’, Leavitt Meadow , 13.viii.1963, flight trap, H.B. Leech (1♀, CASC) , Nevada Co., Sagehen Cr., R. Villegas , 24.vi.1970 (1♀, UCD) , 23.vi.1976 (1♀, UCD) , Sagehen Cr., nr. Hobart Mills , 15.vii.1964, M.E. Irwin, Malaise in meadow (1♀ 2?, UCR) , Placer Co., E end Bear Val. , 2.vi.1964, P.H. Arnaud, Jr. (1♀, CASC) , San Mateo Co., Daly City, 21.xi.1960, K. Leavey, Santa Cruz Co. , Santa Cruz , 29.iii.1961, R. Brown (1♀, CASC) , Tulare Co., Johnsondale , 27.iv.1964, J. Doyen (1♂, EMEC) .

Additional material examined. USA. California: Contra Costa Co., Walnut Cr. , foot Shell Ridge , 15.iv.1964, J. Powell (1♂, EMEC) , Nevada Co., Sagehen Cr. , 28.vi.1978, L. R. Bronson (1♂, UCD) , San Diego Co., San Diego , 8.iii.1953, P.H. Arnaud (1♂ 1♀, CASC) , San Luis Obispo Co., 10.ix.1941, R. M. Bohart, ex. lawn grasses (1♂, UCD) , San Mateo Co., San Bruno Mts. , 24.iii.1963, P.H. Arnaud, Jr. (1♂, USNM) , Santa Clara Co., Stanford U., 25.iv.1961, P.H. Arnaud, Jr. (1♀, CASC) . Colorado: Boulder Co., Corona Pass , 10,600’, 11.viii.1961, J.G. Chillcott (1♂, CNC) .

Comments. Although the host for Liriomyza graminaceae is unknown, it is likely that the name given by Spencer will prove appropriate, as this species belongs to a distinct group of species including the European L. flaveola (Fallén) and the Nearctic L. septentrionalis , which has been reared exclusively from Poaceae . This assumption was also made by Spencer (1969, 1981) in his (re)descriptions of L. abnormis , L. cordillerana Sehgal and L. montana . Like most of its Nearctic relatives, L. graminaceae is relatively large with contrasting colouration, there is a yellow halo around the outer vertical bristle (absent in L. abnormis ), the surstylus is reduced, the epandrial and surstylar spines are absent, there is more extensive dorsal sclerotization on the basiphallus, which is produced anterolaterally as dark distolateral rods, the distiphallus is long, thin, medially curved, dorsally-angled and with an apical bowl (ie. pipe-shaped), the hypophallus is fused to the base of the distiphallus, and the large, heavily sclerotized ejaculatory apodeme has dark lateral processes on the pileus ejaculatorius.

Figures

FIGURES 112–115. Liriomyza graminaceae Spencer, male genitalia; 112: ejaculatory apodeme; 113: external components, ventral; 114: phallus, left lateral; 115: phallus, ventral.