Discolomopsis, a new genus of Endomychidae (Coleoptera: Cucujoidea), is described and illustrated based on a fossil endomychid embedded in amber resin from the Dominican Republic. Discolomopsis dominicana sp. nov. is designated as the type species for the genus

Shockley, Floyd W.

English

Hochschulschriftenserver - Universität Frankfurt am Main

211 INSECTA MUNDI, Vol. 20, No. 3-4, September-December, 2006IntroductionStrohecker (1953) listed six species in three sub-families of Endomychidae that have been describedfrom amber. All were embedded in Baltic amber andshared at least one morphological synapomorphylinking them to the extant fauna, making it possibleto assign them to recognizable subfamilies.  Themajority of fossil endomychids have been placed inextant genera in the subfamily Lycoperdininae (for-merly Eumorphinae).Dominican amber forms as the result of harden-ing of the resin of Hymenaea protera Poinar (Legumi-nosae:  Caesalpinioideae), a tree found in the WestIndies.  Inclusions in Dominican amber are wellknown to be much better preserved and not suffer theproblems with compression typical of inclusions inother New World ambers (Grimaldi and Engel, 2005).The exact age of this amber is unknown, but it hasbeen estimated that most Dominican amber datesback to the mid-Miocene, approximately 15-20 millionyears ago (Iturralde-Vicent and MacPhee, 1996).Discolomopsis Shockley, new genusFigs 1-3Description.  Antennae, body, and legs dark reddishbrown. Head: Slightly deflexed; moderately punctate;surface between punctures smooth; fronto-clypealsuture distinct; clypeus transverse, emarginate me-dially along anterior margin; labrum rectangular,anterior margin weakly rounded. Thorax: Trans-verse and covered with long yellowish setae; lateralmargins widely flattened and slightly reflexed; widestat middle; lateral sulci reduced to punctiform foveae;basal sulcus lacking; scutellum relatively large,strongly transverse, lacking conspicuous puncturesand vestiture. Elytron: Shape convex, subglobose,vestiture long and yellowish in color; lateral marginswidely explanate; disc regularly and moderately punc-tate; humeri elevated. Legs: Procoxa and mesocoxaerounded; metacoxa transverse; tarsomeres simple, 3-segmented, bearing small tuft of setae ventrally,narrowly extended underneath; pretarsus appendicu-late. Abdomen: Sterna apparently connate.Etymology. Derived from the combination of theterms “Discolom-” + the Greek suffix “-opsis”, mean-ing “similar in appearance”.  The generic name isbased on the overall similarity of this genus to mem-bers of the family Discolomatidae, most notably thebroad, flattened lateral margins of the pronotum andelytra.Type Species. Discolomopsis dominicana, new spe-cies.Remarks. This genus shares features with taxafrom several different subfamilies of Endomychidaebut is unique in its combination of these features.  Inbody size and shape and overall vestiture, Discolo-mopsis is consistent with genera in the subfamilyAnamorphinae and is therefore referred to that sub-family.  However, its morphology is distinct from anyDiscolomopsis dominicana, a new genus and speciesof Endomychidae (Coleoptera) from Dominican amberFloyd W. ShockleyDepartment of Entomology413 Biological Sciences BuildingUniversity of GeorgiaAthens, GA 30602-2603  USAAbstract.  Discolomopsis, a new genus of Endomychidae (Coleoptera:  Cucujoidea), is described and illustratedbased on a fossil endomychid embedded in amber resin from the Dominican Republic. Discolomopsis dominicanasp. nov.  is designated as the type species for the genus.Key Words. Entomology, taxonomy, new genus, new species, Cucujoidea, fossil Endomychidae212 Volume 20, No. 3-4, September-December, 2006, INSECTA MUNDIextant genera.  The deeply emarginated and lobedclypeus, presence of long yellowish setae on all bodysegments, and the wide flattened margins on thepronotum and elytra combine to readily distinguishDiscolomopsis from all other Endomychidae.Discolomopsis dominicana Shockley,new speciesFigs. 1-3Description. Holotype (female). Body broadly oval,moderately convex; length 2.6 mm; width 1.9 mm.Dorsum shining, dark reddish-brown with long re-curved setae; antennae, palpi, and legs reddish-brown.Head: Slightly deflexed; with sparse vestiture of shortsetae; moderately punctate; surface between punc-tures smooth; eyes large and rather coarsely faceted;fronto-clypeal suture distinct; frons finely punctate;clypeus transverse and emarginate-lobate apically;labrum transverse, anterior margin weakly rounded;maxillary palpi long and slender, 4-segmented, termi-nal palpomere as long as preceding 3 antennomerescombined; antenna 11-segmented and densely setose,basal segment apically expanded, antennomeres II-VII beadlike, club 3-segmented. Thorax: Transverseand covered with long yellowish setae; pronotal discstrongly convex; lateral margins widely flattened andslightly reflexed; widest at middle; anterior anglesstrongly produced; posterior angles right-angled; lat-eral sulci reduced to punctiform foveae; basal sulcuslacking; scutellum relatively large, strongly trans-verse, lacking conspicuous punctures and vestiture.Elytron: Broadly rounded, convex; vestiture longand yellowish in color; lateral margins widely explan-ate, widest at 1/3 of length from base; medial marginwith submarginal stria extending entire length; discregularly and moderately punctate; humeri elevated.Legs: Procoxa and mesocoxa rounded; metacoxa trans-verse; tarsi 3-segmented, tarsomeres simple, bearingsmall tuft of setae ventrally, narrowly extended un-derneath; pretarsus appendiculate, bearing a conspic-uous tooth basally.Material Examined. Holotype (female) from theDominican Republic, embedded in amber, age Mi-ocene; no excavation information was provided withthe specimen, but the age of the amber was providedand suggests its origin to most likely be the youngerdeposits in the Bayaguana area of the southeast partof the island; holotype deposited in the Florida StateCollection of Arthropods (FSCA).Etymology. So named because the holotype is em-bedded in Dominican amber.Remarks. The holotype is most likely female basedon the absence of modifications, ridges, or spines onthe legs, common features of males from similaranamorphine taxa. Genitalia are internal and ob-Figure 1.  Holotype of Discolomopsis dominicana embeddedin amber. A) Dorsal view; B) Lateral view; C) Obliqueventral view. Scale bars = 0.7 mm.213 INSECTA MUNDI, Vol. 20, No. 3-4, September-December, 2006scured in this specimen and are generally impossibleto differentiate in specimens embedded in amber. Theposition of the holotype within the amber is such thatthe specimen is partially transected anterolaterallyby one of the outer facets of the stone. Additionalpolishing to remove some of the surrounding amberwas avoided because of the specimen’s close proximityto the surface of the amber and its position along afractural plane.AcknowledgmentsI would like to thank R. Woodruff, ProfessorEmeritus, from the Florida State Collection of Arthro-pods, for bringing the specimen to my attention. Iwish to thank P.E. Skelley and J.V. McHugh forproviding comments on previous drafts of this manu-script. I also wish to thank J.V. McHugh for the useof microscopy and digital imaging equipment, as wellas providing partial funding support for the study anddescription of this specimen. This work was partiallyfunded by an NSF/PEET grant (DEB-0329115) to J.V.McHugh, M.F. Whiting, and K.B. Miller.ReferencesGrimaldi, D., and M. S. Engel. 2005. Evolution ofthe Insects. Cambridge University Press, NewYork. 755 p.Iturralde-Vicent, M.A. and R.D.E. MacPhee.1966.  Age and paleogeographical origin of Domin-ican amber.  Science 273:  1850-1852.Strohecker, H.F.  1953.  Coleoptera.  Fam. Endomy-chidae.  In:  P. Wytsman, ed.  Genera Insectorum.Fasc. 210.  L. Desmet-Verteneuil, Brussels, 140pp.Figure 2.  Holotype of Discolomopsis dominicana embedded in amber.  A) Dorso-anterior view of the head; B) Dorsal view of headand pronotum; C) Dorsal view of medial elytral suture; D) Lateral view of the tarsi with claws.  Scale bars = 0.3 mm.214 Volume 20, No. 3-4, September-December, 2006, INSECTA MUNDIFigure 3. Line drawings of Discolomopsis dominicana. A) Dorsal habitus; B) Dorsal view of head; C) Close-up of left antenna; D)Ventral view of left prothoracic leg; E) Ventral view of left mesothoracic leg; F) Ventral view of right metathoracic leg.  Linein A-B marks the outer facet of the amber, which transects a portion of the fossil.

Discolomopsis dominicana : a new genus and species of Endomychidae (Coleoptera) from Dominican amber

Abstract

Similar works

Full text

Available Versions

Hochschulschriftenserver - Universität Frankfurt am Main