Melissites trigona, Engel, 2001

ENGEL, MICHAEL S., 2001, A Monograph Of The Baltic Amber Bees And Evolution Of The Apoidea (Hymenoptera), Bulletin of the American Museum of Natural History 2001 (259), pp. 1-1 : 1-

Melissites trigona , new species Figures 105–110 Plate 6d

DIAGNOSIS: As for the genus (see above).

DESCRIPTION: Female. Total body length 4.22 mm; forewing length 4.00 mm. Head

wider than long (length 1.25 mm, width 1.53 mm). Upper interorbital distance 0.97 mm; lower interorbital distance 0.73 mm. Interocellar distance 0.37 mm; ocellocular distance 0.22 mm; median to lateral ocellus 0.12 mm. Intertegular distance 1.00 mm. Basal vein confluent with cu­a; 1rs­m distad 1m­cu by eight times vein width; 2rs­m distad 2m­cu by 1.5 times vein width; first submarginal cell shorter than combined lengths of second and third submarginal cells; length of posterior border of second submarginal cell slightly less than twice anterior border; length of anterior border of third submarginal cell three­quarters that of posterior border, 1.25 times length of anterior border of second submarginal cell; six distal hamuli arranged in a single, evenly spaced series (fig. 110).

Integument of head and mesosoma smooth and impunctate. Terga and sterna imbricate and impunctate.

Head and mesosoma black. Antennae, legs, and metasoma dark brown except apical margins of terga light brown to pale yellow. Wing membrane hyaline; veins strong and dark brown.

Pubescence lightly infuscated. Setae of face widely scattered, simple, and short; such setae longer on vertex. Gena with simple, short, appressed setae; postgena with long, simple setae sparsely scattered. Mesoscutum with sparse, simple setae, more sparsely scattered and shorter on central disc. Pubescence of scutellum as described for mesoscutum except two or more times longer, plumose, and dense on posterior half. Metanotum without pubescence. Hypoepimeral area without pubescence; remainder of mesepisternum and metepisternum with scattered, simple, long setae. Basal area and posterior surface of propodeum without pubescence; lateral surface with scattered, minute, suberect, simple setae. Pubescence of legs generally simple and scattered except inner surfaces of mesotrochanter and mesofemur without pubescence and outer surface of mesotibia with dense, branched setae; inner surface of metafemur and metatrochanter without pubescence except apical quarter of metafemur with dense field of keirotrichiae; inner surface of metatibia with keirotrichiate zone; corbicular setae simple; seven comb rows on inner surface of metabasitarsus, each composed of stiff, elongate, simple setae; outer surface with scattered, long, simple setae. Terga and sterna with short, simple, sparse setae.

MATERIAL: One specimen. Holotype. Female, worker caste, B­JH 102 ( AMNH) labeled: ‘‘Baltic amber: Eocene, Kaliningrad, Yantarny’’ // ‘‘ Holotype, Melissites trigona Engel’’.

ETYMOLOGY: The specific epithet is taken (as a noun in apposition) from the genusgroup name Trigona (Meliponini) and is a reference to the overall, superficial resemblance of this species to some stingless bees.

Genus Roussyana Manning , status novus Electrapis (Roussyana) Manning, 1960: 306.

Type species: Apis palmnickenensis Roussy,

1937, original designation. Zeuner and Man­

ning, 1976: 233.

Russyana Petrov, 1992: 361. Lapsus calami .

DIAGNOSIS: Roussyana most closely resembles Melissites ; both genera have the distinctive banding of the metasoma owing to the apical margins of the terga being very pale brown in comparison to the remainder of the terga, which are dark brown. The genus can be separated from Melissites by the strongly narrowed second submarginal cell, basal vein basal to cu­a, and the approximately parallel compound eyes.

DESCRIPTION: Malar space short, shorter than basal mandibular width. Epistomal sulcus forming obtuse angle; clypeus without basal clypeal protrusion. F1 longer than F2; F2 equal to F3. Inner margins of compound eyes roughly parallel. Preoccipital ridge rounded. Mesoscutal anterior border broadly rounded; tegula oval; scutellum bulging, projecting over metanotum and basal area of propodeum. Basal area of propodeum declivitous. Keirotrichiate field not elevated; metatibial spur serrate; auricular basket sparse, setae short; rastellum strong and formed of stiff setae; lateral margins of metabasitarsus converging toward apex. Three submarginal cells; anterior border of second submarginal cell much shorter than r­rs. Metasomal terga banded.

Figures

Fig. 105. Frontal view of holotype female head of Melissites trigona, new species. Scale bar = 0.5 mm.

Figs. 106–108. Leg structures of holotype female of Melissites trigona, new species. 106. Outer surface of metatibia and metabasitarsus. 107. Inner surface of metatibia and metabasitarsus. 108. Claw and arolium. Scale bar = 0.5 mm (figs. 106, 107); 0.25 mm (fig. 108).

Figs. 109–110. Wings of holotype female of Melissites trigona, new species. 109. Forewing. 110. Hind wing. Scale bars = 1 mm (a = fig. 109; b = fig. 110).