Sambomorpha panama, López-Guerrero, 1924

López-Guerrero, Irma, 1924, Figs. 30 – 33. Attavicinus monstrosus. 30 in Comparison of Mouthpart Morphology of Three Species of Mexican Oniticellini (Coleoptera: Scarabaeidae: Scarabaeinae) in Relation to Their Trophic Habits, The Coleopterists Bulletin 1924 (3), pp. 471-475 : 471-475

Sambomorpha panama , new species

( Fig. 3 )

Description of holotype. Gender unknown, small, length 4.8 mm from anteriormost point of frontovertex between eyes to elytral apex, width 1.4 mm at widest posterior midpoint of pronotum; elongate, ovoid; flattened above, feebly transversely convex below; color black with faint bluish reflections; surface of head, pronotum and thoracic ventrites imbricate; head, pronotum and lateral portions of thoracic and abdominal ventrites finely, transversely rugose; anterolateral portion of abdominal ventrite 1 imbricate in metafemoral depression; elytra coarsely shagreened; abdominal ventrites finely punctate; dorsal surface with irregular pattern and densities of short, recurved, stout white setae as follows: pronotum with setae slightly concentrated in short anteromedial band, slightly in median line and then lateral or posterior to medial portion of disk, elytra with concentrations in medial portion just posterior to scutellum, with broad irregular fasciae anterior to midpoint, one irregular fascia between 474 posterior 1/3 to 1/4, then two small spots, one on each elytron preapically; ventral surface with very sparse covering of fine white adpressed setae.

Head with frontovertex with longitudinal groove widening to broad depression between slightly anteriorly produced, feebly arcuate lobes between large eyes; eyes elliptical, each with narrow black margin; circumocular groove from beyond dorsal-most point along inner margin until becoming confluent with narrow, horizontal genal groove for reception of basal antennomeres in repose; antennal cavities large, widely separated, each bordered dorsally by small transverse groove; frontoclypeus with distal margin arcuately emarginate; gena broadly obtusely lobed beneath eye; antennae with antennomere 1 short, robust; 2 subequal to 1; 3 slightly shorter, more robust than 2; 4 subequal to, but slightly wider apically than, 3; 5–10 triangularly serrate, each much wider than long; 11 oblong, slightly oblique to 10.

Pronotum about 1.5 times wider than long, widest posterior to midpoint; anterior margin arcuate medially; posterior margin bisinuate on either side of medial arcuate lobe, narrow marginal fringe nearly impunctate across entire width except posteriorly where it is feebly crenulate; posterolateral angles obtuse; lateral margin straight, oblique from posterior margin then becoming broadly arcuate, widening from base to before midpoint, then narrowing to anterior margin, margin slightly explanate, carinate along entire length; disk with a broad, shallow depression on either side in posterolateral portion; one bisinuate carina on either side, just before lateral margin. Scutellum small, subcordiform, acuminate posteriorly.

Elytra not as wide as pronotum, widest opposite humeri, depressed basally between humerus and scutellum; lateral margin narrowing from opposite humeri to past anterior 1/3, then widening gradually to before posterior 1/3, before narrowing to separately rounded, serrulate apices; lateral margin carinate from anterior margin to about midpoint, separating disk from epipleuron, which is widest anteriorly, narrowing to fine margin before becoming confluent at a point opposite suture between abdominal ventrites 1 and 2; disk more or less even, flattened medially, rounded laterally; sutural carina becoming slightly more pronounced toward apex.

Prosternum with broadly bilobed mentonierre, a deep transverse groove posterior to anterior margin; hypomeron with anterior groove continuing from genal groove for distal antennomeres in repose; narrow lateral portion of hypomeron beneath pronotal carina and laterally produced away from plane of disk; metacoxa short, broad, with posterior margin bisinuate to rounded acute posterolateral angle which is visible from above; length of adominal ventrites 1 and 2 together greater than 3–5; suture between 1 and 2 only faintly visible laterally; sutures between 2, 3, 4 and 5 feebly arcuate; fine marginal groove present between the abdominal pleurites and ventrites, extending premarginally around entire margin of 5; pygidium not visible from above.

Legs: femora slightly fusiform proximally; tibiae strongly flattened, much wider than thick, arcuate on external margin; pro- and mesotibiae shorter than femora, metatibia slightly longer than metafemur; metatibia with setal comb on external edge for about middle1/3 of length; tarsi with tarsomeres 1–4 each short, with ventral pulvilli that are slightly longer from 1 to 4; 5 narrow, elongate, subequal in length to 1–4 together, claws bifid, inner claw much shorter.

Genitalia: not dissected, gender unknown.

Specimens examined. Holotype ( USNM): PANAMA: P(ana)ma Pr (ovince)., Llano-Cartí Rd., Km-9 El. 350 m., 8 Jan. ‘83 Stockwell.

Etymology. This new species is named for the country of origin.

Comments. Sambomorpha panama can be distinguished from S. costarica by the subtle differences in color, vestiture and surface sculpture. However, these two species differ significantly with the very different character states in the legs since S. costarica has the tibiae typically cylindrical contrasted with the strongly flattened tibiae of S. panama ; this could in fact be a sexual character. The character states of the setal comb on the metatibiae differ with S. costarica having the comb more diffuse over much of the outer edge while S. panama has the comb concentrated to the middle third of the metatibiae.

Figures

Figures 1–3. Sambomorpha spp. Fig. 1) S. costarica Bellamy, 1997, holotype; Fig. 2) S. corona, sp.nov. holotype; Fig. 3) S. panama, sp. nov. holotype. Scale bars 5 1.0 mm.