Agrilus parvus californicus Westcott and Nelson

Westcott, R. L. & Nelson, G. H., 2000, Descriptions Of Two New Species Of Acmaeodera Eschscholtz, And Two New Subspecies Of Agrilus Curtis And Chrysobothris Eschscholtz (Coleoptera: Buprestidae) In North America, With Detailed Notes On Others, The Coleopterists Bulletin 54 (3), pp. 300-312 : 308-309

Agrilus parvus californicus Westcott and Nelson , new subspecies

Holotype. Male. 4.1 mm long, 1.2 mm wide; closely similar to the nominate subspecies, including the male genitalia, except for the presence of two small, usually rounded, smooth foveae on the dull metallic blue­green frons, each just medial to the middle of the eye.

Allotype. 4.8 mm long, 1.5 mm wide; frons brassy with coppery reflections, foveae as in male except contrasting green.

Material Examined. Holotype labeled ‘‘CALIFORNIA: Riverside County/ E of Hemet, Jct. San Jacinto R. & Hwy. 74, 6­VI­1993 G.H. Nelson/on AMOR­ PHA FRUTICOSA OCCIDENTALIS / HOLOTYPE Agrilus parvus californicus WESTCOTT & NELSON’’ (h; red label); allotype labeled ‘‘USA:CAL San Diego Co, NW Sec 20, T 12S, R 2E, 1.2 mi WNW Coral Mt., 24. VI.1988 CLBellamy, on Amorpha fruticosa ’’, both deposited in CASC. Paratypes as follows: California, Riverside Co., 18 M, 12 F, same data as holotype; 1 M, same except 28­V­95; 1 M, 10 mi E Hemet, 8­V­80, D. G. Kissinger, A. f. occidentalis; 4 M, 11 mi E Hemet, Hwy. 74, 8­VII­86, D. S. Verity, on A. fruticosa ; 1 M, Santa Rosa Mts., Pinyon Flats, 6­VI­81, G. C. Walters, on Ceanothus sp. San Diego Co., 35 M, 24 F, same data as allotype; 4 F, Warner Springs, 29­V­78; 5 M, 6 F, Hot Springs Lookout, 7­VII­78, both Brown & Faulkner; 4 M, 4 F, Black Canyon Camp, 9 mi N Ramona, 2­VII­65, C. D. Johnson, sweeping A. fruticosa ; 11 M, 11 F, 8 mi N Ramona, Black Can., 23/ 24­VI­84, G. H. Nelson; 1 M, 2 F, 7.5 mi N Ramona, 19­VI­86, B. K. Dozier, both on A. f. occidentalis. Mexico, Baja Calif. N., 3 M, 1 F, Río San Salvador at Hwy. 3, 1,070 m, 31°52̍24̎N, 116°05̍27̎W, (7–12)­VI­97, malaise trap, M. E. Irwin, E. I. Schlinger. Paratypes in BMNH, CASC, CDAE, CIDA, CLBC, DSVC, EMEC, FSCA, GCWC, GHNC, INHS, LACM, MNHN, NAUF, NMPC, RLWE, SDMC, SGWC, TCMC, UCDC, UNAM, USNM, WFBC, WFBM, ZMAS.

Variation. The male frons varies in color from dull metallic green to bluegreen. In females it is brassy, usually with coppery or greenish reflections. The foveae vary from clearly developed (usually) to indistinct, rarely absent. In the female usually they contrast, being of a color like the male frons. In size, the males range from 3.6–4.6 mm long (ave. 4.2 mm, N = 25), females are 4.0– 5.3 mm long (ave. 4.5 mm, N = 23).

Comparison. The frontal foveae are absent in A. p. parvus , rarely indistinct or absent in A. p. californicus; otherwise there is no apparent difference other than distributional.

Biology. Larval habits are unknown. Most adults were found on the foliage of A. fruticosa (the variety occidentalis (Abrams) Kearn. & Peeb. is not recognized by Hickman (1993)), and since A. p. parvus is also collected from foliage of that plant, undoubtedly it is a larval host for both subspecies.

Biogeography. Based on collections of A. parvus we have seen, and distribution of the putative host genus, Amorpha L. ( Wilbur, 1975), the two subspecies are widely allopatric. Agrilus p. californicus is limited to southwestern California and adjacent Baja California. Although the nominate subspecies and the host genus range widely from central Arizona (Yavapai Co.) eastward, we have no records of the beetle from Nevada or Utah, and Wilbur (1975) did not record the host genus from either of those states.

Etymology. The name reflects geographic distribution.