Bura Mulsant

Vandenberg, Natalia J. & Perez-Gelabert, Daniel E., 2007, Redescription of the Hispaniolan ladybird genus Bura Mulsant (Coleoptera: Coccinellidae) and justification for its transfer from Coccidulinae to Sticholotidinae, Zootaxa 1586, pp. 39-46 : 44-45

Bura Mulsant

Bura Mulsant, 1850:374 , 419. Type species: Bura cuprea Mulsant , by monotypy.

Diagnosis: Distinguished from most other Sticholotidini by the combination of circular, hemispherical to superhemispherical body form ( Figs. 2–3 ), by the shape and development of the eye canthus ( Fig. 1 ), clypeus not emarginate around antennal insertion, distal maxillary palpomere nearly parallel-sided ( Fig. 7 ), and tarsal claw with a large subtriangular basal tooth ( Fig. 8 ).

Redescription: Form ( Figs. 2–3 ) compact, hemispherical to superhemispherical, shiny with metallic sheen; dorsum apparently glabrous except for sparse marginal setae. Punctation on dorsal surfaces distinct, with intermixed large/small punctures on elytron, single-sized punctures on head and pronotum; minute seta associated with each puncture, scarcely visible using standard light microscopy. Head ( Figs. 1–3 ) vertical, widest at middle of eye, tapered toward clypeus with scattered setae at inner margin of eye and anterior margin of clypeus; labrum distinctly narrower than clypeal margin, moderately setose, joined to clypeus by conspicuous trapezoidal membrane. Head capsule with slightly raised bead along inner margin of eye. Eyes ( Fig. 1 ) well-developed, dorsally divergent; facets somewhat flattened, eye canthus long and narrow, with distal end slightly up-curved, partially dividing eye, subcarinate proximally, with several rows of facets visible below its ventral margin. Anterior, lateral margins of clypeus reflexed, not emarginate at antennal insertion. Antenna ( Figs. 1, 5–6 ) inserted laterally beneath clypeal margin, moderately short and compact, composed of ten antennomeres; club gradual, well-developed, spindle shaped; mesal surface of penultimate antennomere projecting anterolaterally, with brush of short setae in small semi-membranous patch near apex; last antennomere with scattered short setae in distal half and dense concentration of short setae in large semi-membranous patch on mesal surface; both setal patches with indistinct boundaries. Mandible with bifid apex of which inner tooth shorter and thicker than outer tooth. Mentum moderately broadly joined to submentum. Distal maxillary palpomere ( Fig. 7 ) elongate, nearly parallel-sided, apically pointed, with long oblique sensory surface. Distal labial palpomere elongate, tapered to very small round sensory surface. Pronotum with marginal bead continuous along base and lateral margin to inner anterior angle directly behind inner margin of eye, very narrowly, faintly indicated beyond; anterior angle and lateral margin narrowly reflexed, with short widely spaced setae along reflexed edge. Elytron with lateral margin narrowly, sharply reflexed with distinct lateral bead bearing sparse short setae. Scutellum small, triangular. Pronotal hypomeron with depression to receive retracted antennal club. Prosternum forming a modified T or Y-shape ( Fig. 4 ); short stem strongly raised above level of lateral arms with carinae distinct at least in anterior half and joined to form an inverted U. Coxae broadly separated; meso- and metasternites compactly joined with dividing sutures partially obliterated. Femur robust; tibia simple, slender, not externally dentate, apical spurs lacking; tarsi cryptotetramerous; claw with well developed triangular tooth at base ( Fig. 8 ). Elytral epipleuron broad in anterior half, may be subfoveolate to receive femoral apices in repose, complete, inner margin narrowed by arcuate expansion of abdomen, tapered toward apex. Abdomen with five ventrites, extreme tip of sixth may be visible in males; postcoxal line of first ventrite curved posterolaterally, not quite attaining junction of posterior and lateral margins. Male genitalia with slender curved sipho; basal lobe and parameres elongate, bilaterally symmetrical or nearly so; basal piece symmetrical, lacking eccentric dorsal strut.

Remarks: In general facies, Bura looks very similar to many of the photographs of Australian Sticholotis species in a recent publication by Ślipiński (2004), but the latter have the clypeus emarginate around antennal insertions, distal maxillary palpomere spindle-shaped (apically convergent), median part of prosternum anteriorly produced, tarsal claw simple or merely broadened at base (lacking triangular tooth), and basal piece of male genitalia asymmetrical, with an eccentric dorsal strut.

Bura appears to be closely allied to many of the Neotropical sticholotidine genera described by Gordon (1969, 1977, 1991, 1994c), but these are generally small to minute beetles (1.8 to1.25 mm in length) while Bura cuprea exceeds 2.5 mm and can reach up to 3.2 mm in length. In addition to the greater size, Bura can be distinguished primarily by the well-developed triangular tooth of the tarsal claw ( Fig. 8 ). It is perhaps most similar to the genus Lenasa Gordon (1994c), but the latter is much smaller, more oval and less convex in body form, and with only a small acute tooth at the base of the tarsal claw. Bura also shares some features with the “cocciduline” taxa of the West Indies ( Chapin 1930, Gordon 1994b), but in this case the overall similarity is not sufficient to cause any confusion in identification.

In his recent study of Sticholotis, Ślipiński (2004) chose to recognize a single broadly defined genus rather than continuing to segregate specialized species based on loss of flight wings or reduction in number of antennomeres. Presently, the Neotropical Sticholotidini consists of a number of small genera which share many features with Bura and with each other. If the trend begun with Sticholotis is continued in the world revision of Sticholotidinae (Ślipiński in prep.), we might expect a number of Neotropical sticholotidine genera to fall into synonymy with Bura . In particular the genus Lenasa does not differ from Bura except in the overall size and proportions of various body parts, not normally considered significant differences at the generic level.

Figures

FIGURES 1 – 8. Bura cuprea Mulsant, adult specimen: 1. Head capsule, frontal view of left half showing compound eye and eye canthus; 2. Whole beetle, frontal view; 3. Same, left lateral view; 4. Prosternum, ventral surface; 5. Right antenna, lateral view; 6. Right antenna, distal portion, rotated to show patches of short sensory setae on mesal surfaces of last two antennomeres; 7. Left maxillary palp, ventral view; 8. Tarsal claw showing triangular tooth at base.