The Family Melittidae in Madagascar (Hymenoptera, Apoidea)

Abstract

6. -La premlkre Abeille Mel~tt~dae connue de Madagascar (Agemmonra I) est i c ~ dCcrite. Flle appartlent au genre Agemmonia de 1'Afrlque de t; elle est placCe dans le nouveau sous-genre Drtromonra. mmary. -The first known Melitt~d bee from Madagascar (Agemmonia nzeli) IS liere described. It belongs to the east Afrlcan genus Agemmonra, but is placed in a new subgenus Dl~romonra. lie arclialc bee family Melittidae is more abundant and diversified in southern tern Afr~ca than in any other part of the world (Michener, 1981). Nonetheless t been found previously in Madagascar. The discovery of a species in Mada-therefore of special interest. It is a member of the subfamily Meganomiinae, hitherto known only in tropical xeric areas of eastern and southern Africa; known soutli of the Tropic of Capricorn. the key to the genera of Meganomiinae (Michener, 1981) the Malagasy bee 2 but does not agree with e~ther alternative. It probably runs best to ernmonla but differs in that the front edge of the median ocellus is farther from the tennal bases than from the posterior edge of the vertex and the first flagellar segment male is only about 2.5 times as long as greatest width. The other similar genus is nia from which the Malagasy bee differs in the forward position of the ocelli ough not as far forward as in Agemmonia), the inner orbits diverging below, the n-segmented male flagellum and tlie relatively simple, robust penis valves. In a series of other characters not mentioned in tlie key to genera, such as tlie g~tudlnal ridge on the clypeus, tlie broad face, the broad supraclypeal area margined erally by short subantennal sutures that diverge upward, the slender male antenna1 e, the simple legs of the male with extraordinarily large pretarsi (claws, arol~a), etc., Malagasy species is most similar to Agemmonia. Relationships are best ind~cated I placlng it in that genus, although as a subgenus distinct from the Afr~can forms. In e description below, major characters are italicized; characters are lettered to facilitate Manuscrlt accepte le 14-XI-1986 Contr~butlon number 1942 from the Department of Fntomology, Un~vers~ty of Kansas 99 comparison with M~chener's (1981) generic descr~ptions. It seemed best t o list all o the generic characters (except, of course, those of the unknown female) since in mo cases s o m e change o r broadening of Michener's (198 1) character~zation of Agemmon 1s necessitated. Abbreviations such as T 1 a n d S 1 are used for the metasomal terga and sterna, respectively. DICROMONIA n. subgen. Type species: Agemmonia (Dicromonia) wenzeli, n. sp. Male. Dzagnosrs. Flagellum simple, slender, eleven segmented, segment 1 abou 2.5 tlmes as long as greatest breadth, segments 2-10 a b o u t a s long a s broad (varym with curvature of flagellum); labrum less t h a n three times a s wide a s long; arolla lar T o p of head gently convex seen f r o m front, ocelll far In front of posterlor marg vertex. Pygidial plate absent, T7 deeply bifid. Apex of metasoma curled anteri Description: a. Length 15 mm; forewing length 10.75 mm. Longer hairs plumose. forming striking beard on under side of head. b. Face broad, inner orbits parallel in upper ha1 sligl~tly converging above at upper extremities, diverging below in lower halves. c. 2.1 times as n,ide as long (fig. I) with longitudinal median ridge. d. Clypeal truncation no recognizable, lower 1.lypea1 margin gent& convex at superficial level; if narrow, depressed, d margin is considered, then a feebly defined truncation, two thirds as wide as distance antennal sockets, gently curves to straighter part of clypeal margin which becomes con laterally. e. Subantennal sutures distinctly diverging above, half as long as shallowly V-sha clypeo-supraclypeal suture (fig. I). f. Summit of head, seen from front, gently convex. g. Oc slightly in front of summit of head;.posterior ocellus separated from posterior margin of ver by over two ocellar diameters; anterior edge qj' median ocellus slightlv nearer 11 vertex than antennal bases. h. Gena much narrower than eye seen from side. i. Mandible weak upper tooth near apex, in repose completely covering labrum. j. Labrum less than t times as wide as long, most!^ smooth and depressed but ~sith wreak ridge across