Mesa SAUSSURE 1892

Boni, M., 2013, Afrotropical taxa of the genus Mesa SAUSSURE 1892 (Hymenoptera, Tiphiidae, Myzininae), Linzer biologische Beiträge 45 (2), pp. 1657-1744 : 1660

Genera Mesa SAUSSURE 1892 and Hylomesa KROMBEIN 1968

ARGAMAN 1994: 90.

BONI BARTALUCCI 2004b: 22-25.

In general habitus Mesa females show similarities with females of tribe Myzinini (stout body, mostly punctured integument; also wing venations of both fore and hind wing are almost identical and very distinct from Meriini and to remind their differences could be useful (see also BONI BARTALUCCI 2004b). Members of Hylomesa are easily recognizable mainly by strongly backward produced head and strong gradulus present on 1 st tergal disk. Like other members of Old World Myzininae Mesa and relatives are well distinct from American Myzinini ( fig. 1, 2, 3 ) and Australian Austromyzinini mainly by 2 character states ( BONI BARTALUCCI 2004b):

– cOc never broken ventrally by the hypostoma whose ventral border (the cHy) is never prominent over the plane of the lower genae; FoO clearly shorter than genal areas in ventral aspect &); consequently PoG normally expressed (&) ( figs 42 , 170 ).

– First metamerus always petiolate; first tergum overlies sternum just backward; forward either it gets ribbon-like and fused to the sternum or is absent; in the last case the petiole is formed by the sternum only (figs 4, 66) (&).

The latter (shared only with Meriini ) it is unique within the whole Tiphiidae (sensu antiquo). Because of that, it carries a strong weight both in taxonomic and geographical considerations.

Figures

Figs 1-3: Myzinum sp.: (1) head, lateroventral aspect, (2) head, ventral aspect, (3) first metamerus, lateral aspect. Fig. 4: Meria sp.: 1st metamerus, lateral aspect. Figs. 5-9: Mesa sp: (5) scape, (6) 5th flagellomerus, (7) forewing, (8) hindwing, (9) fore tibial spur; (1-3: scale bar "a": 1 mm; 4: scale bar "b": 1 mm; 7-8: scale bar: 2 mm; 9: scale bar: 0.5mm).

Figs 40-44: Mesa abdominalis: (40) habitus, (41) clypeus and lower head, frontal aspect (42) head, ventral aspect (43) labium, ventral aspect, (44) idem, lateral aspect; (40: scale bar: 5 mm, 41: scale bar: 1 mm, 43-44: scale bar: 0.5 mm).

Figs 169-176: Mesa campsa: (169) habitus; (170) head, ventral aspect; (171) basal hindtarsomerus. Mesa campsa: (172) head, frontal spect; (173) epipygium; (174) gonosquama; (175) volsella; (176) aedeagus; (169: scale bar: 5 mm; 172: scale bar: 1 mm; 173-176: scale bar: 0.5 mm).