Baliosus randia Riley

Riley, Edward G., 2015, Three New Hispine Beetles (Coleoptera: Chrysomelidae: Cassidinae) from the United States and a New United States Record, The Coleopterists Bulletin (mo 14) 69, pp. 183-190 : 183-185

Baliosus randia Riley , new species

( Fig. 1 )

Holotype. Sex undetermined, labeled “TEX: Cameron Co. | 12.5 mi. E. Browns- | ville on Hwy. 4; | X-14-88: E. G. Riley ∥ on Randia | rhagocarpa ∥ HOLOTYPE | Baliosus | randia | Riley”. Specimen ( Fig. 1 ) is in excellent condition, all appendages intact. Deposited in TAMU.

Paratypes. 47 specimens. TEXAS: Cameron County, Sabal Palm Grove Sanctuary, near Southmost , V-18-1979, E. G. Riley [2 EGRC]; same data as holotype [2 ♂♂, 3 ♀♀, 9 sex undetermined BYU, EGRC]; same data as holotype, except R . S. Anderson [13 AJGC, TAMU, USNM]; 13.5 mi. E Brownsville, X-11-1994. E. G. Riley [2 EGRC]; “Ebony Loma” 12.5 mi. E Brownsville, V-5-1989, E. G. Riley [2 TAMU]; Sabal Palm Grove Refuge , site 1, 25.84799°N, 97.41881°W, IV-23-2009, J. King & E. G. Riley-835, beating palm forest [1 TAMU]; same locality, III-7-2009, M. A. Quinn & E. G. Riley-485, beating palm forest [1 TAMU]; same locality, except –site 10, 25.84964°N, 97.41798°W, X-19-2008, E. G. Riley-278, beating palm forest [1 TAMU]; Sabal Palm Grove Sanctuary, IV-4-2009, E. G. Riley [1 TAMU] .

Description. Body elongate, length 2.9–3.4 mm (mean = 3.1 mm, n = 13), width across humeri 1.2–1.5 mm (mean = 1.4 mm, n = 13), greatest width usually across posterolateral elytral angles, depressed above, pronotum and elytra deeply punctate; pronotum markedly narrower than base of elytra; head narrower than anterior margin of pronotum; dorsal ground color pale yellowish brown often suffused with brownish, with darker brown maculae on pronotum and elytra; elytral maculae of darkest specimens often with faint aeneous reflection; venter reddish brown with sides of metasternum dark brown to nearly black; antennae dark brown to nearly black; legs entirely yellowish brown. Head: Feeble, longitudinal elevation between upper extreme of antennal sockets; vertex minutely granulose with broad, shallow, longitudinal impression; shallow, narrow groove present along internal margin of each eye; clypeus wider than long, feebly elevated across base, impunctate, yellow in color; eye large, occupying almost entire side of head, genal space very narrow. Antenna: Moderately long, gradually clavate, with 11 freely articulating antennomeres; antennomeres stout, cylindrical; scape very slightly shorter than antennomere II; antennomeres II–IV subequal in size and shape, antennomeres IV–VI subequal in length and each slightly shorter than II or III; antennomeres VII–XI more densely setose than preceding; antennomeres VII–X subequal in length; XI about twice as long as X, apex bluntly rounded. Pronotum: Wider than long (length/width ratio = 0.68–0.73), greatest width at mid-length, anterior and posterior margins transverse; lateral margins each with strong, elevated bead, parallel for posterior half and gently curved inward anteriorly to anterolateral angle; anterolateral angle with short, stout, seta-bearing nodule; disc uniformly covered with large deep punctation, surfaces between punctation smooth and shining; disc with pair of elongate maculae anteriorly and another macula posterolaterally on each side, brownish. Elytra: Coarsely punctate, subparallel-sided, humeri prominent and equal in width to preapical width or preapical width slightly greater; lateral margins strongly serrate. Punctation on each elytron aligned in 8 or 9 rows anteriorly (post umbo) plus a short scutellar row of 1–3 punctures; rows 1–4 geminate between sutural and 1 st and 2 nd discal costae; rows 5–8 reduced anteriorly behind umbo to 2 or 3 discernable rows, irregular subapically to form patch of confused punctation. Costae 1 and 2 non-serrate, depressed pre-apically adjacent to the region of confused punctation and costa 1 raised at base; costa 3 on each elytron lost medially, present anteriorly postumbo as short indistinct ridge and present preapically as distinct oblique ridge; costa 4 complete, serrate throughout, raised preapically. Dark maculae range from medium brownish to dark brown with weak aeneous reflection, present as broken oblique band at base, a conjoint median spot, pair of postmedian bands forming X-shape that does not encompass the suture, and transverse preapical band that extends forward briefly at suture; all bands highly fragmented, posteriormost bands encompassing epipleuron and visible from below in heavily marked specimens; epipleuron below humerus pale. Venter: Prosternum shiny, finely impressed medially, and with few scattered punctures posteriorly; hypomeron of prothorax smooth and shiny, with or without few large punctures; metasternum with row of large punctures adjacent to posterior margin of mesocoxae, medially sparsely punctate with minute punctation, shiny, laterally with numerous closely spaced large punctures; abdominal ventrites impunctate, finely alutaceous. Legs: Outer margin of mesotibia arcuate, outer margins of pro- and metatibiae straight.

Etymology. This species is named for the plant genus on which it feeds, treated as a noun in apposition.

Geographical Range. Presently known only from the extreme lower Rio Grande Valley near Brownsville , Texas .

Biological Notes. I have taken this species on multiple occasions by beating Randia rhagocarpa Standl. ( Rubiaceae ) growing on the clay hills east of Brownsville, Texas, and again on this plant growing in the Sabal Palm Grove Preserve, a remnant of southern Texas palm forest. Confined adults fed readily on the leaves, producing short etching-type scars on the upper leaf surfaces, damage that was also observed in the field. Larvae were not observed.

Remarks. This species can be confused with members of the genus Sumitrosis Butte to which it bears an overall general resemblance. It is with some hesitation that I place this new species in Baliosus Weise , as it further pushes the limits of variation in the serial punctation of the elytra included in that genus, but there seems to be no better generic placement available.

In the present species, the elytral punctation is less regular than that seen in other Baliosus where most have 10 more-or-less well-defined rows as the base number on each elytron, with or without some constriction at mid-length involving rows 5–8. In the present species, the 10-row condition is reduced anteriorly to eight or nine rows (counted in the post humeral area), reduced at mid-length to eight rows, and reduced posteriorly to a confused punctate patch between the third and fourth costae. There is some variation observed in the intensity of the dark markings of the dorsum, with the darkest specimens having elytral markings with faint aeneous reflections. A specimen with moderately intense markings is figured.

Figures

Figs. 1–2. Dorsal, ventral, and lateral views of holotype and holotype labels: 1) Baliosus randia; 2) Heptispa brevicornis. Scale bar = 1 mm.