Lema trabeata Lacordaire

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 : 6-9

Lema trabeata Lacordaire

( Figures 1-2)

Lema trabeata Dejean 1835: 359 [nomen nudum].

Lema confusa, var. trabeata Lacordaire 1845: 409 . Diagnosis. The connate tarsal claws (claws that are broadly contiguous in the basal half), as well as the general appearance ( Fig. 1-2), immediately distinguish this species from all other chrysomelids known to occur in the Cayman Islands. Neolema dorsalis (Olivier) , a common and widespread species that may eventually be found in the Cayman Islands, also has connate claws, but the appearance is quite different. In that species, the elytra are orange with a large, black, bell-shaped marking in the basal half and with another large black marking in the posterior half.

Material examined. Cayman Islands, Grand Cayman , Arboretum, 10-VI-2010, K. Palmer, KP65B, Datura metel (1, BYUC; 4, FSCA) .

Extralimital distribution. On the mainland, this species occurs from the southern United States to Central America ( Riley et al. 2003). Additionally, the similar species Lema confusa Chevrolat (with L. trabeata being listed as a synonym) has been reported from Cuba, Jamaica, and Puerto Rico ( Takizawa 2003). Some of these West Indian records may have been based on L. trabeata .

Plant associations. This beetle species has been associated with various plants in the family Solanaceae ( Clark et al. 2004) . As indicated above, specimens in the Cayman Islands have been collected from the solanaceous plant Datura metel L.

Comments. The color pattern of the Cayman Islands specimens varies somewhat. In four of the five specimens, the elytra have a broad, irregularly shaped, black band beginning near the lateral margin and extending across the suture; the elytral apex is also black ( Fig. 1). In the fifth specimen, the would-be band of each elytron is broadly interrupted by yellow and thus forms a lateral longitudinal stripe, plus a second longitudinal stripe that is confluent with the stripe of the other elytron ( Fig. 2). The elytral pattern of this specimen is like that of the similar and perhaps synonymous species L. confusa . In three of the five specimens, the head and prothorax are nearly all black. However, in two of the specimens (including the specimen with the broadly interrupted elytral marking), the posterior portion of the head and much of the prothorax, except for dark lateral maculae and a median pronotal stripe, are pale brown. In earlier works, L. trabeata was treated as a subspecies, variety, or strict synonym of L. confusa . White (1993) elevated L. trabeata to species rank, distinguishing it from L. confusa based on the extent of the dark elytral markings. However, his justification for this taxonomic change is not altogether convincing. In fact, he stated that some specimens of L. trabeata “are essentially identical with L. confusa ” and that he had “not been able to find characters that will distinguish them from L. confusa .” Future investigation may show that the two supposed taxa are no more than color forms of a single variable species.