Tracheliodes grimaldii, Melo & Rosa, 2019

Melo, Gabriel A. R. & Rosa, Brunno B., 2019, A new fossil species of the crabronid wasp genus Tracheliodes (Hymenoptera: Crabronidae) from Dominican amber, Zoologia (e 36293) 36, pp. 1-5 : 1-4

Tracheliodes grimaldii sp. nov.

http://zoobank.org/ CB5DF3D6-3B55-4115-8AC4-693B70FA4F21

Figs 1–9

Diagnosis. Tracheliodes grimaldii sp. nov. can be set apart from the living taxa by the following combination of characters: (1) Thick setae along lower margin of clypeus relatively short, their length subequal to diameter of antennal socket; (2) Clypeal disc weakly convex, without medial protuberance; (3) Distance between antennal socket and eye orbit short, subequal to the distance between sockets; (4) Upper frons and vertex relatively flat, without conspicuous undulations of the integument; (5) Fore femur fusiform, not expanded ventrally, its lower surface devoid of thick bristles; (6) Mid femur fusiform, not expanded dorsally; (7) Mid tibial spur unmodified and relatively short; (8) Hind femur strongly thickened in the basal third, its anterior surface mostly flat; (9) First metasomal segment petiolate, dorsal surface of petiole convex; (10) Pygidial plate tear-shaped, with relatively weak preapical narrowing.

Description. Female holotype. Measurements (in mm). Approximate body length, 6.5; maximum head width, 1.9. Pilosity. Head and mesosoma mostly glabrous with sparse, fine and very short appressed hairs. Lower margin of clypeus with preapical line of long setae, their length subequal to diameter of antennal socket, lateral ones longer, thicker and slightly curved inwards; clypeal disc with sparser and shorter setae on its upper half; lower margin of gena with short and dense pilosity; parocular area, along scapal basin, with a dense strip of short, decumbent hairs facing outwards; dorsal surface of scape with numerous decumbent micro-setae. Anterior half of lateral portion of mesepisternum, behind omaular carina, with conspicuously dense short pilosity. Foreleg: lower surface of femur devoid of thick bristles; basitarsus with a row of short and thick bristles along inner margin, its posterior margin with a row of five bristles, bristles almost as long as diameter of basitarsus. Midleg: femur with thick bristles on posterior surface, inner surface with erect bristles directed towards apex, those on ventral surface slightly longer; anterior surface of tibia, right above the spur, with a pair of conspicuous lanceolate bristles; apical third of tibia with short thick setae on outer surface, these similar to those on remainder of tibia (not forming spininiform bristles), except for an apical pair of thick spiniform bristles. Hindleg: trochanter with a conspicuous patch of short decumbent setae; femur with thick relatively long bristles on anterior surface, bristles erect and directed towards apex; tibia with sparse, very thick, short bristles on outer surface; basitarsus with row of thick and short bristles forming a comb along its inner margin. Metasoma without conspicuous pilosity, except for few short setae on ventral portion of S6 and on margin of T6 bordering pygidial plate. Integumental surface. Head and mesosoma finely microreticulated, dull. Pronotum with few parallel carinae in front of pronotal lobe. Posterior two-thirds of lateral surface of mesepisternum, metepisternum, and lateral portion of propodeum finely microstriated, striation more conspicuous on mesepisternum and metepisternum; omaular carina well developed and reaching mesepisternal sulcus ventrally, adjacent region behind carina with small foveae; mesepisternal sulcus weakly indicated and not foveolated. Structure. Head: clypeus transverse, its lateral portions very narrow, its lower margin with three broad teeth in the middle, lateral teeth aligned with antennal socket, disc weakly convex without projection; tentorial pit situated at the transition between inner and lower orbits, area around it weakly depressed; distance between antennal sockets subequal to the distance from socket to the inner orbit of compound eyes; scapal basin relatively shallow, only slightly depressed relative to lateral surface; distance between lower inner orbits approximately 0.7× width of eye in frontal view; gena in lateral view approximately 1.2× as wide as compound eye; upper frons and vertex relatively flat, without conspicuous undulations of the integument; ocello-orbital distance 1.6× the distance between posterior ocelli; distance between anterior and posterior ocelli about half the distance between the posterior ocelli; facial fovea linear, its length about 1.4 the distance between posterior ocelli. Foreleg: femur fusiform, not expanded ventrally. Midleg: femur fusiform, not expanded dorsally, its lower portion flat, apical portion of anterior surface weakly excavated ventrally; tibial spur short, less than one-third of basitarsal length; basitarsus cylindrical, oval to circular in section. Hindleg: trochanter basically circular in section; femur strongly thickened in the basal third, its maximum height approximately 2.5× apical height, anterior surface mostly flat; hind tibia clavate as in other species of the genus; basitarsus gently curved and approximately 1.35× as long as mid basitarsus; inner tibial spur about 1.8× as long as outer spur. Metasoma: 1st segment petiolate and gradually broadening posteriorly; width of petiole approximately one-fourth of apical width of T1, in lateral view; dorsal surface of petiole convex; pygidial plate tear-shaped, flat, with relatively weak preapical narrowing, its margins limited by a low carina.

Type material. Holotype female, in amber piece AMNH no. PB- 118, bearing the following labels: ‘Amber: Dominican Republic,\Specific Locality unknown\(Oligomiocene). Purchased in\ Santo Domingo by Paul F. Burke.\AMNH no. PB- 118\Identifications:/ Sphecidae /Platypodidae’ ‘PB118’. The piece measures 12 x 10 x 6 mm, and possesses a dark reddish orange color. The amber forms a darker reddish halo around the wasp specimen. The wasp wings are folded downward, making it difficult to observe both the wings and the metasoma; also, there are numerous air bubbles around its metasoma. There is a small beetle ( Platypodinae , Curculionidae ) at ca. 2 mm above the holotype.

Etymology. The species is named after the curator of AMNH’s amber collection, David A. Grimaldi, who has kindly made the material available for study.