Megistops adiae, Clark & Lillrose & Belo Neto, 2013

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 : 25-26

Megistops adiae , new species

( Figures 18, 37, 45)

Diagnosis. The large, apically truncate and bifurcate spur at the apex of each hind tibia is alone sufficient to distinguish this from all other chrysomelid species known to occur in the Cayman Islands. For specimens in which the position of the legs makes this character difficult to see, the large, nearly contiguous eyes, in combination with the greatly enlarged hind femora and essentially impunctate elytra, will also quickly enable identification. Similarly colored species of Megistops elsewhere in the West Indies are M. bahamensis Blake from the Bahamas, M. parvula Blake from Jamaica, and M. tabebuiae Blake from Cuba. In comparison with M. adiae , the elytral markings of well-marked specimens of M. bahamensis are less irregular in shape, and the aedeagus is much more arcuately broadened before the apex. The aedeagus of M. parvula is more similar to that of M. adiae , but the pale areas of the body are reddish brown instead of yellowish brown, the elytral markings are much smaller, the anterior marking sometimes being entirely absent, and the hind femora are pale (femora largely piceous in M. adiae , except for in the pale specimen from Grand Cayman). The aedeagus of M. tabebuiae is also similar to that of M. adiae , although Blake (1937) illustrated the sclerotized orificial covering as being much wider. The venter of M. tabebuiae is described as being yellowish or reddish brown. In M. adiae , the venter and hind femora are largely piceous (except for in the palely marked specimen from Grand Cayman).

Description of male. Form elongate oval, narrower in front than behind; length 3.0 mm; width 1.7 mm. Head yellowish brown; pronotum yellowish, sometimes marked with vaguely indicated darker maculae; scutellum piceous; each elytron dark piceous with two large yellowish maculae, these sometimes narrowly connected; ventral areas dark brown; legs yellowish brown with hind femora largely darkened.

Head with frontal tubercles small, well indicated, separated from each other by distinct sulcus. Frons below antennae flattened. Eyes very large, nearly contiguous above. Antennae filiform, narrowly separated by short ridge; antennomeres 1-3 yellowish brown; intermediate antennomeres dark piceous; distal one or two antennomeres yellowish brown; antennomeres 1 and 2 nearly glabrous; antennomeres 3-11 densely setose; basal antennomere largest, about three times as long as 2 or 3, which are shortest; antennomeres 4-11 subequal in length. Labrum, tip of mandibles, and distal portion of maxillary palpi largely piceous.

Pronotum approximately half as long as wide, 0.25 times as long as elytra, 1.8 times as wide as head; shape convex, narrowing anteriorly, with slightly curved sides, with well-developed anterolateral tubercle, with basal margin slightly sinuous over scutellum; surface very finely, confluently punctate, rugulose; surface between punctures shining; color yellowish, sometimes with vaguely indicated darker maculae, three in basal half, two in anterior half. Scutellum small, triangular, piceous.

Elytra 1.4 times as long as wide, 0.8 times as long as entire body. Shape smoothly convex, without depressions. Surface somewhat shiny, faintly alutaceous upon close inspection. Punctation extremely fine, nearly absent. Color of each elytron piceous with two large yellowish maculae, one in basal half and one in distal half, these maculae sometimes narrowly connected; basal macula somewhat oblique; margins of both maculae very irregular in shape.

Ventral surface dark brown, with abdomen slightly paler. Legs yellowish brown, with coxae dark brown, with hind femora largely darkened; hind femora much enlarged, 1.8 times as long as wide; hind tibiae broadly channeled distally, with apical spur broad, apically truncate and bifurcate; basal tarsomere of all legs very broad. Terminal ventrite of abdomen with median lobe. Aedeagus as in Figure 37.

Description of female. Form, size, and color similar to male, but differing as follows: length 3.1-3.2 mm; elytral pale markings either as in male, or more extensive, occupying most of disc, leaving only margins dark; hind femora either darkened as in male, or nearly entirely pale yellowish brown; basal tarsomere of all legs narrower; terminal abdominal ventrite apically rounded, without median lobe; spermatheca as in Figure 45.

Material examined. Holotype: “CAYMAN, Cayman Brac, north shore bluff, 24 May 2009 R. Turnbow” (male, FSCA) . Paratypes: Cayman Islands, Cayman Brac , north shore bluff, 24-V-2009, R. Turnbow (1 male, BYUC; 1 female, RHTC) ; Cayman Islands, Grand Cayman , Queen Elizabeth Botanical Garden , 28- V-2009, Thomas , Turnbow and Ball, blacklight trap (1 female, FSCA) .

Plant associations. Unknown.

Etymology. The species epithet of this taxon honors the grandmother of the third author.

Comments. The specimen from Grand Cayman is much paler than the others. Even so, we believe that it belongs to the same species. Similar variability is known in other West Indian species of Megistops .