Euglossa (Euglossa) cotylisca, HINOJOSA-DÍAZ & ENGEL, 2007

HINOJOSA-DÍAZ, ISMAEL A. & ENGEL, MICHAEL S., 2007, A New Fossil Orchid Bee in Colombian Copal (Hymenoptera: Apidae), American Museum Novitates 3589, pp. 1-8 : 2-5

Euglossa (Euglossa) cotylisca , new species figures 1 , 2

Euglossinae ; Ross, 1998: 63.

Euglossa sp. ; Engel, 2001a: 176.

DIAGNOSIS: Integument uniformly brilliant metallic green ( fig. 1 ), with golden highlights; ivory white paraocular marks well developed; labrum, mandibles (although apices are likely brown but cannot be discerned in the fossil), and malar space ivory white. Metatibiae with a deep central, integumental depression on outer surface ( fig. 2 ), following the widest area of the metatibial organ slit’s outer section.

DESCRIPTION: Male. Body length about 10 mm, head width about 4.5 mm. Malar space length not exceeding flagellar diameter. Labral windows oval, occupying about twothirds of labral length, closer to clypeus; midlabral ridge well developed and sharp, lateral ridges well developed on upper twothirds of labrum. Clypeus moderately protruded (i.e., face not flattened), middle ridge sharp, lateral ridges well developed on upper part. Surface of mesocutellum even, not bigibbous, posterior border straight. Metatibia with anterior border (the one abutting

670 [1]) in Colombian copal; setae and punctation omitted; drawn as viewed from a very slightly oblique aspect.

metafemur when contracted) as long as, or slightly shorter than, ventral border (the opposing border); dorsoposterior border (the diagonal edge) divided in two sections by deep notch on area where dorsal section of metatibial organ slit is present ( fig. 2 ); metatibial organ slit dorsal and outer sections well defined with a junction narrower than the contiguous width of dorsal section; apex of dorsal section acute; outer section spurshaped; outer surface of metatibia with a large, deeply impressed central depression following the widest area of the metatibial organ slit’s outer section (such a depression is present in some modern species, but only faintly so and never to the degree seen in the fossil; this is not an artifact of preservation as there is no compression anywhere on the specimen and the same feature is identical on both metatibiae).

Entire individual brilliant metallic green ( fig. 1 ), with golden hue particularly on mesoscutum, mesoscutellum, and metatibia. Ivory paraocular marks well developed running from at least (as much as can be seen) area of antennal insertion to clypeus; marks slightly wider at lower extreme, not exceeding 1.5 times the width at the level of antennal insertion, and occupying about 0.2 of the eye– clypeus disc distance. Labrum and mandibles ivory, mandibular coloration apparently typical for most Euglossa (i.e., ivory with borders and teeth brown). Malar space completely ivory. Major podites of legs brilliant metallic green; tarsomeres (except basitarsi) brown as typical for most Euglossa .

Frontal fringe moderately dense, formed of dark, erect, simple setae about as long as 1 OD. Vertex with longer (about 1.5 OD), scattered setae like those of frontal fringe, concentrated on intra-ocellar area, lateral depressions (formed between the border of compound eyes and ocellar monticule), and forming a sparse occipital fringe. Supralateral areas surrounding clypeus with some setae as those on vertex; clypeus covered with scattered setae of the same nature but about one-half length of those on frontal fringe. Antennal depressions with moderately dense, whitish, plumose setae; scape with some scarce short setae; pedicel with two dark, erect, small apical setae, otherwise bare; flagellum with fulvous, very short, simple setae scattered over surface; flagellar articles 3 through 11 with usual frontal sensillae. Lower gena with long, whitish, plumose setae. Pronotal lobe with dense setae, darker, thicker, and longer than those on notum, intermixed with some short, fine, whitish, plumose (finely branched) setae that continue to cover pleural and ventral areas of mesosoma, similar setae on ventralfacing surface of mesoscutellum. Mesoscutum and mesoscutellum with even layer of moderately dense, dark, erect, simple setae, as long as those on frontal fringe; posterior border of mesoscutum with row of scattered, slightly longer setae. Legs covered with moderately dense, light, short setae. Protarsal podites with dense, long, yellowish setae forming chemicalgathering brushes; tibiae with long, whitish setae on posterior areas, especially on median section of dorsoposterior border of metatibia (right after slit notch); dense, dark, sturdy setae on inner surface of meso- and metabasitarsi; metatibal organ slit closed with dark setae. Metasomal terga covered with light, short setae.

Female. Unknown.

HOLOTYPE: Male , Quaternary Colombian copal, Santander, Colombia, BMNH Pal. PI II 670 (1), M. Caycedo, 24 March 1995 ( fig. 1 ). The specimen resides in the Department of Palaeontology, the Natural History Museum, London.

ETYMOLOGY: The specific epithet is derived from the Latin term cotyliscus (meaning ‘‘cupshaped cavity or hollow’’) and is a reference to the deep depression of the metatibiae.

PRESERVATION: The piece of copal entombing the bee is the size of a small fist. The sole Euglossa individual is close to the straight cut, which offers the best view of the numerous insects encapsulated in the resin. The view of the bee through this surface shows the dorsal and left sides with excellent detail; however, owing to the distortion caused by the resin flows, numerous fractures, and the opacity of the resin on the remaining surfaces, no other areas of the bee can be seen with clarity, except for a small portion of right metatibia and the right side of the head. The head is rotated about 90 ° to the right, allowing the vertex to be seen perfectly. The labiomaxillary complex is extended, although the maxillae are not entirely protruded. The apices of the mandibles cannot be seen. The legs are all held against the body and oriented in a way that renders it impossible to see the modified setose areas of the left mesotibia. The seventh metasomal tergum and sixth metasomal sternum are not completely closed so that the extreme apex of the genital capsule can be observed.

Figures

Fig. 1. Photomicrograph of Euglossa (Euglossa) cotylisca Hinojosa-Díaz and Engel, new species (NHML Pal. PI II 670 [1]) in Colombian copal; above, a view of the entire piece encapsulating the bee; below, dorsal aspect of the bee in detail. [Upper image by I.A.H.-D., 2006; lower image by P.V. York, reproduced with permission of the NHML, º The Natural History Museum, London].

Fig. 2. Metatibia of Euglossa (Euglossa) cotylisca Hinojosa-Díaz and Engel, new species (NHML Pal. PI II