Pachybrachis notatus Bowditch, 1910

Barney, Robert J., 2023, Redescriptions of the Pachybrachis Chevrolat (Coleoptera: Chrysomelidae: Cryptocephalinae) of Arizona, Including New Synonymies, State Records, Plant Associations, and Descriptions of New Species: The Robust Species, The Coleopterists Bulletin 77 (3), pp. 439-459 : 451-452

11. Pachybrachis notatus Bowditch, 1910 ( Fig. 6 )

Pachybrachys notatus Bowditch 1910: 53 . Fall 1915: 391 (taxonomy).

Pachybrachis notatus : Riley et al. 2003: 160 (catalog).

Type. Bowditch (1910) described P. notatus based upon a single male specimen from the Santa Rita Mountains. Bowditch’s male holotype, labeled “ Santa Rita Mts. / Ariz. 5 to 8000 ft. / July, F. H. Snow [printed italics, white paper] // ♂ // notatus B. / Type [hand-inked, white paper] // Type. / P. notatus / Bowd. [hand-inked within lined border, red paper] // [circular blue disc signifying dissection by RJB] // HOLOTYPE / Pachybrachys / notatus Bowditch / R. J. Barney 2023 [printed, red paper]”, was examined, dissected, and photographed ( Fig. 6 ).

Redescription. Male. Yellow with black-brown maculae; L = 3.59–4.25 mm (mean = 3.89 mm, n = 7); W = 1.98–2.38 mm (mean = 2.18 mm, n = 7); L/W = 1.72–1.85 (mean = 1.79, n = 7). Head: Slightly wider than thoracic apex, HW = 0.39– 1.64 mm (mean = 1.52 mm, n = 7); eyes moderately separated, IOD = 0.36–0.49 mm (mean = 0.41 mm, n = 7), IOD/HW = 0.25–0.30 (mean = 0.27, n = 7); face yellow with black to brown, W-shaped macula connecting vertex and bases of antennae and up to base of upper lobes of eyes; no ocular lines; punctation dense in dark areas, sparser in pale areas, antennae brown to black, almost reaching elytral declivity. Pronotum: Yellow with black, M-shaped maculae; punctation dense in dark areas, more sparsely placed in pale areas, especially along lateral margins; PL = 1.17–1.27 mm (mean = 1.25 mm, n = 7); PW = 1.85–2.15 mm (mean = 1.98 mm, n = 7); PL/PW = 0.62–0.75 (mean = 0.64, n = 7). Elytra: Yellow with scattered brown to black maculae; striae irregular, with little inter-strial punctation. Pygidium: Black. Venter: Dark brown-black. Legs: Yellow with brown-black spots; front claws slightly enlarged. Genitalia: Median lobe in en-face view wide, large oval OS, extended POS, curved to terminus with setae visible at ALA and pre-terminus; medial lobe in lateral view with inflated base into rounded keel, both sets of setae plainly visible. Four males from Arizona and California were dissected.

Female. As in male, except L = 4.15–4.38 mm (mean = 4.23 mm, n = 3); W = 2.28–2.37 mm (mean = 2.35 mm, n = 3); L/W = 1.72–1.85 (mean = 1.80, n = 3); HW = 1.55–1.65 mm (mean = 1.60 mm, n = 3); IOD = 0.44–0.53 mm (mean = 0.50 mm, n = 3); IOD/HW = 0.28–0.34 (n = 3).

Remarks. Fall (1915) was unable to examine the holotype, but I was fortunate to borrow it from SEMC ( Fig. 6 ). Additional study may show that P. notatus is but a darker, western synonym of Pachybrachis subvittatus J. L. LeConte. The median lobes of these species are virtually identical.

Distribution. Riley et al. (2003) reported P. notatus as from Arizona and P. subvittatus from New Mexico and Texas. The California specimens listed below represent a new state record.

Biological Notes. Two of the California specimens were labeled as collected from Dalea sp. ( Fabaceae ), while the third was labeled as collected from Ephedra sp. ( Ephedraceae ). One male from Yavapai County was labeled as from “beating Ceanothus ” ( Rhamnaceae ).

Specimens Examined. Holotype plus 17 specimens. USA: CALIFORNIA: Inyo Co., Westgard Pass Tollhouse area, 25.vi.1980, ex Dalea sp. and Ephedra sp. , A. J. Gilbert and R. Gill [3♂♂, AJGC]. ARIZONA: Pima Co. , Santa Rita Mts. , 5 to 8,000 ft., vii, F. H. Snow [1♂, HOLOTYPE, SEMC]; Santa Rita Mts., Rosemont area, 4,400 –6,175 ′, 15.vii.1975, J. Busacca and C. Olson [3♂♂, UAIC]; Tucson Mts. , Gilbert Ray Campground, 23.vii.1975, UV light, G. H. Nelson [1♂, FSCA]; Santa Catalina foothills, 11.vii.1975, K. Stephan [1♂, FSCA]; Yavapai Co. , 28 mi NW Wickenburg, 20.iv.2007, C. W. and L. B. O’Brien [1♂ 1♀, BYUC]; Yarnell, 27.vi.1964, ex Ceanothus, G. H. Nelson [2♂♂ 4♀♀, FSCA; 1♂, AJG].

Figures

Fig. 6. Pachybrachis notatus, Santa Rita Mountains, Arizona, holotype. A) Dorsal habitus, B) Lateral habitus, C) Face, D) Pygidium, E) Median lobe of aedeagus, lateral view, F) Median lobe of aedeagus, en-face view.