Pachybrachis species 1

Clark, Shawn M., Lillrose, Tiffany & Belo Neto, Luiz A., 2013, Leaf Beetles of the Cayman Islands (Coleoptera: Chrysomelidae), Insecta Mundi 2013 (279), pp. 1-41 : 36-37

Pachybrachis species 1

( Figure 31)

Diagnosis. In the Cayman Islands, this genus is distinguished from other chrysomelids by the wellformed basal bead of the pronotum, the exposed pygidium, and the front femora that are enlarged in comparison to those of the middle and hind legs. This species differs from the other Cayman Islands species of Pachybrachis in numerous characters, including the larger body size (3.0- 4.2 mm, compared to 2.0- 2.3 mm long), the eyes that are narrowly separated (by much less than the length of the basal antennomere in males, by about the length of the basal antennomere in females), and the more polished integument.

Material examined. Cayman Islands, Cayman Brac, Bight Rd., Brac Parrot Pres. , 24-V-2009, Thomas, Turnbow & Ball, blacklight trap (5, FSCA) ; Cayman Islands, Cayman Brac, Bight Rd., Brac Parrot Pres. , 25-V-2009, Thomas, Turnbow & Ball, blacklight trap (6, FSCA) ; Cayman Islands, Cayman Brac, Brac Paradise Subdivision , 22-V-2009, Thomas, Turnbow & Ball, bl trap (4, FSCA) ; Cayman Islands, Cayman Brac, Brac Paradise Subdivision , 6-VI-2008, M. C. Thomas, R. H. Turnbow, B. K. Dozier, blacklight trap (2, FSCA) ; Cayman Islands, Cayman Brac, Brac Parrot Reserve , 24-V-2009, R. Turnbow (1, RHTC) ; Cayman Islands, Cayman Brac, jct. Hemmington Rd. at Songbird Dr. , 6-VI-2008, M. C. Thomas, R. H. Turnbow, blacklight trap (2, RHTC) ; Cayman Islands, Cayman Brac, jct. Hemmington Rd. at Songbird Dr. , 8-VI-2008, M. C. Thomas, R. H. Turnbow, B. K. Dozier, blacklight trap (10, FSCA) ; Cayman Islands, Cayman Brac, Hemmington Road at Songbird Drive , 24-V-2009, Thomas, Turnbow & Ball, blacklight trap (4, BYUC; 30, FSCA) ; Cayman Islands, Cayman Brac, Long Beach , 23-V-2009, R. Turnbow (2, RHTC) ; Cayman Islands, Cayman Brac, Long Beach , 24-V-2009, M. C. Thomas (1, FSCA) ; Cayman Islands, Cayman Brac, Long Beach , 24-V-2009, R. Turnbow, on Cocoloba uvifera (L). L. (1, RHTC) ; Cayman Islands, Cayman Brac, Major Donald Dr., 0.4 km E. jct. Ashton Reid Dr. , 23-V-2009, R. Turnbow (1, RHTC) ; Cayman Islands, Cayman Brac, Major Donald Dr., 0.6 km E. jct. Ashton Reid Dr. , 5-VI-2008, M. C. Thomas, R. H. Turnbow, blacklight trap (1, RHTC) ; Cayman Islands, Cayman Brac, Major Donald Dr., 0.6 km E. jct. Ashton Reid Dr. , 6-VI-2008, M. C. Thomas, R. H. Turnbow, B. K. Dozier, blacklight trap (2, FSCA) ; Cayman Islands, Cayman Brac, Major Donald Dr., 0.6 km E. jct. Ashton Reid Dr. , 7-VI- 2008, R. Turnbow (1, RHTC) ; Cayman Islands, Cayman Brac, Major Donald Dr., 0.6 km E. jct. Ashton Reid Dr. , 8-VI-2008, M. C. Thomas, R. H. Turnbow, B. K. Dozier, blacklight trap (1, FSCA) ; Cayman Islands, Cayman Brac, Major Donald Dr. at Bight Rd. , 22-VI-2009, R. Turnbow (1, FSCA) ; Cayman Islands, Grand Cayman, vicinity Gun Bay, 4-VI-2008, R. Turnbow, on Conocarpus erecta (1, RHTC) ; Cayman Islands, Little Cayman, North Coast Road , 0.1 km west Olivine Kirk Dr., 26-V-2009, Thomas, Turnbow & Ball, blacklight trap (7, FSCA) ; Cayman Islands, Little Cayman, North Coast Rd., 0.1 km west jct. Olivine Kirk Rd. , 27-V-2009, Thomas, Turnbow & Ball, bl trap (1, FSCA) ; Cayman Islands, Little Cayman , 0.3 km SE Spot Bay, 26-V-2009, Thomas, Turnbow & Ball, bl trap (2, FSCA) ; Cayman Islands, Little Cayman , 0.3 km SE Spot Bay, 26-V-2009, R. Turnbow (1, RHTC) .

Plant associations. As noted above, one specimen was collected from Conocarpus erectus L. ( Combretaceae ) and another from Cocoloba uvifera (L). L. ( Polygonaceae ).

Comments. In the West Indies, as well as in many other areas, the genus Pachybrachis is in need of a great deal of taxonomic investigation. Many of the named species are inadequately described. The aedeagus, which is distinctive for many species, has never been illustrated for most of them. Beyond the named species, many others are yet to be described. Indeed, the two Cayman Islands species are very likely both unnamed endemics. However, considering the taxonomic difficulties with the genus, we have chosen not to name them at this time. Pachybrachis sp. 1 belongs to a group in which the integument is polished and the eyes, especially in the males, are very narrowly separated. Such species are found on many of the West Indian islands. In some ways, they resemble Mastacanthus Suffrian , a genus known only from Cuba. Indeed, future study may prove that they are better placed in that genus.