Pachybrachys connexus Fall 1915: 328
Pachybrachis connexus : Riley et al. 2003: 156
Definition and Revision of the Pubescens Species-Group of North American Pachybrachis Chevrolat (Coleoptera: Chrysomelidae: Cryptocephalinae), Including Descriptions of Three New Species
Barney, Robert J.
The Coleopterists Bulletin
2019
2019-12-19
73
4
1017
1048
Fall, 1915
Fall
1915
[235,580,1391,1412]
Insecta
Chrysomelidae
Pachybrachis
Animalia
Coleoptera
4
1020
Arthropoda
species
connexus
Pachybrachys connexus Fall 1915: 328. Pachybrachis connexus: Riley et al.2003: 156 (catalogue).
Type. Fall (1915)described P. connexusfrom a single female labeled “HotSprgs [printed] / 27.6 [hand-inked] Ar [printed, white paper] // Barber& / SchwarzColl [printed, white paper] // TYPE[printed] / connexus[hand-inked, white paper] // TYPE USNM[printed] / #71969 [hand-inked, red paper] // connexus[hand-inked] / Fall 1915Revis. [printed, white paper] // USNMENT / barcode / 0071322 [printed, white paper]”. This specimen was examined and photographed ( Fig. 13A).
Redescription. Male.Rufo-testaceous, subsutural and marginal black stripes on elytra, connected narrowly along base and broadly along declivity ( Fig. 1); L = 1.86–2.28 mm(mean = 2.03 mm, n= 10); W = 0.91–1.15 mm(mean = 1.00 mm, n= 10); L/W = 1.95–2.08 (mean = 2.02, n= 10). Head:Distinctly wider than thoracic apex, HW = 0.66–0.78 mm(mean = 0.72 mm, n= 10); eyes narrowly separated, IOD = 0.11–0.17 mm(mean = 0.13 mm, n= 10); IOD/HW = 0.12–0.23 (mean = 0.18, n= 10); face primarily dark brown with white recumbent pubescence; antennae yellow-brown, not reaching elytral declivity. Pronotum:Rufo-testaceous, with faint M-shaped macula, covered with white recumbent pubescence; PL = 0.54–0.70 mm(mean = 0.64 mm, n= 10); PW = 0.82–0.96 mm(mean = 0.88 mm, n= 10); PL/PW = 0.65–0.80 (mean = 0.72, n= 10). Elytra:Yellow with subsutural and marginal black stripes connected narrowly along base and broadly along declivity, with white pubescence. Pygidium:Dark brown with white pubescence. Venter:Dark brown with white pubescence. Legs:Yellow with brown areas and white pubescence; front claws not enlarged. Genitalia:Median lobe in en-face view with large, oval OS, widest at ALM, abruptly narrowing to pointed terminus. Base to terminus straight in lateral view, though moderately inflated. Six males from three USAstates were dissected. Fig. 2. Pachybrachis wickhami, lectotype. A–B) Dorsal and lateral habitus, respectively, C) Face, D) Pygidium, E–F) Median lobe of aedeagus, lateral and en-face views, respectively. Female.As in male, except L = 2.10–2.56 mm(mean = 2.31 mm, n= 10); W = 1.10–1.47 mm(mean = 1.19 mm, n= 10); L/W = 1.61–2.04 (mean = 1.95, n= 10); HW = 0.69–0.84 mm(mean = 0.77 mm, n= 10); IOD = 0.21–0.31 mm(mean = 0.25 mm, n= 10); IOD/HW = 0.27–0.35 (mean = 0.32, n= 10).
Remarks. Fall (1915)described this species based upon a single female from Hot Springs, Arizona, collected on 27 June by Barber and Schwarz. Fall’ s personal collection did not contain any examples (personal communication, Rachel L. Hawkins, MCZ). Pachybrachis connexusis readily identifiable among pubescent species due to the striping on the elytra.
Distribution.This species is found in southeastern Arizona, California, and Nevada(Map 1A). Nevadais a new state record. Hot Springs, Arizonais possibly Verde Hot Springs in Gila County. Biological Notes.A large series of P. connexuswere collected on E. fasiculatumin California. Some specimens were collected via UV blacklight in Arizonaand California, and Malaise and pitfall traps in California.