Archeorhinotermes rossi, KRISHNA & GRIMALDI, 2003

KRISHNA, KUMAR & GRIMALDI, DAVID A., 2003, The First Cretaceous Rhinotermitidae (Isoptera): A New Species, Genus, and Subfamily in Burmese Amber, American Museum Novitates 3390, pp. 1-11 : 4-5

Archeorhinotermes rossi , new species

IMAGO ( figs. 1 , 2 ; table 1): Head, antennae, and pronotum light brown, wing scale brownish, lighter than head, legs light yellow. Head moderately covered with long bristles, longest about 0.18 mm; upper margin of forewing scale with several short bristles; costal margin and radial sector with a few barely visible short bristles; tergites and sternites densely covered with long bristles; fore, middle, and hind tibia with several long, thin bristles; inner margin of middle and hind tibia with a row of additional short, thicker bristles; tarsal segments with several long bristles. Head small, roundish, slightly

TABLE 1 Measurements (mm) of Holotype Imago of Archeorhinotermes rossi , new species

Length of head to tip of labrum 0.77 Width of head 0.69 Maximum diameter of eye 0.24 Minimum diameter of eye 0.13 Maximum diameter of ocellus 0.09 Ocellus from eye 0.04 Length of labrum 0.23 Width of labrum 0.23 Length of postclypeus 0.10 Length of forewing scale 0.64 Length of forewing with scale 4.39 Width of forewing 0.97 Length of middle tibia 0.39 Length of hind tibia 0.56

longer than wide. Eyes medium­sized, oval, not bulging much beyond head. Ocelli large, separated from eyes. Fontanelle present, appearing closer to hind margin than to postclypeus. Labrum oblong, with lateral margins faintly rounded. Postclypeus narrow, not prominently arched. Pronotum tucked under head, not clearly visible, but appearing narrower than head. Left mandible with a prominent rounded projection near the apical tooth; apical tooth long and prominent, longer than first, second, or third marginal tooth, with outer margin sinuate; first, second, and third marginal teeth almost equal in length; molar prominence pointed, appearing as a fourth marginal tooth. Right mandible with a subsidiary tooth at base of upper margin of first marginal tooth (characteristic of Hodotermitidae , Termopsidae , and Rhinotermitidae ); second marginal tooth prominent, equal in length to first marginal tooth, posterior margin with a medium­sized cutting edge (longer in all other rhinotermitids). Antennae broken, with 13+ articles; second subequal to third; third and fourth subequal. Tibial spurs very hard to distinguish from thick bristles at end of tibia, appear to be 3:2:2. Tarsus with four articles. Arolium absent. Cerci with two articles. Forewing membrane reticulate, particularly between branches of cubitus; R 1 and R 2 absent; Rs simple, unbranched, running close to the fused subcosta and costal margin; median arising from a common stem with Rs, inside wing scale, unbranched, running almost midway between Rs and cubitus, appearing joined to cubitus, close to apical margin; cubitus arising independently from inside wing scale, with 11 branches, fourth with a sub­branch.

SPECIMEN AND TYPE LOCALITY: Imago (holotype) in amber, NHM, Department of Palaeontology number In. 20160, received from R.C.J. Swinhoe, July 1920. Myanmar ( Burma):?Hukawng Valley. Spherical piece of amber, 10 mm in diameter, with a 2­mm wide hole bored through center (originally a bead), containing one termite (as above), one Cecidomyidae , one Acarina, one Auchenorrhycha nymph, four Coleoptera (?family), one Coleoptera (Mordellidae) , one Heteroptera ( Saldidae ), two Diptera (Ceratopogonidae) , and one male Coccoidea. The holotype is deposited in the Department of Palaeontology (Invertebrates), Natural History Museum, London. Burmese amber is dated as Upper to Middle Cretaceous, probably Turonian– Cenomanian (90–100 mya) by Grimaldi, Engel, and Nascimbene (2002).

ETYMOLOGY: This species is named in hon­ or of Andrew Ross, Curator of Fossil Arthropods, Department of Palaeontology, Natural History Museum, London, and an authority on Burmese amber.

Figures

Fig. 1. Holotype imago of Archeorhinotermes rossi, n. sp. a, dorsal view of head; b, dorsal view of mandibles; c, ventral view of middle tibia and tarsus; d, dorsal view of forewing.

Fig. 2. Photomicrograph of the holotype imago of Archeorhinotermes rossi, n. sp.