Archeofoenus, Engel, 2017

Engel, Michael S., 2017, New Evanioid Wasps from the Cenomanian of Myanmar (Hymenoptera: Othniodellithidae, Aulacidae), with a Summary of Family-Group Names among Evanioidea, American Museum Novitates 2017 (3871), pp. 1-28 : 12-16

Archeofoenus , new genus

TYPE SPECIES: Archeofoenus tartaricus , new species.

DIAGNOSIS: The new genus is similar to Protofoenus but differs in the large compound eye that encompasses the majority of the length of the head in profile (with a short malar space); the broadly bidentate mandible (with prominent, pointed, triangular subapical tooth as long as apical tooth); the uniformly clear wing membranes (without any indication of infuscation) (fig. 3); forewing 2Rs subequal to 2Rs+M, r-rs equal to 2Rs, 2Rs+M and 2Rs weakly angled (nearly forming a straight line), and 2M+Cu entirely absent (fig. 4A); the gena dark brown to black (without any indication of maculation); the metafemur dark brown except yellow at apex (rather than yellow along the majority of its length); and the metatibia yellow except at its extreme apex and on the majority of its inner surface dark brown. In addition, the genus is noteworthy for the broadly rounded profile of the anterior border of the mesoscutum, which is itself raised high above the pronotal posterior border, and the Y-shaped notauli.

ETYMOLOGY: The new generic name is a combination of the Greek, arche (“beginning”) and Foenus Fabricius , an early generic name among the Evanioidea . The gender of the name is masculine.

Archeofoenus tartaricus , new species

Figures 3–5

DIAGNOSIS: As for genus (above).

DESCRIPTION: ♀: Total length as preserved (excluding antennae and ovipositor) 4.80 mm; forewing length 3.25 mm; dark brown to nearly black preserved colors, except yellow as follows: on profemur except basally and apically, protibia except inner surface, apical half of mesofemur, mesotibia except apical half of inner surface, apex of metafemur, metatibia except at extreme apex and majority of inner surface; integument with minute, fine, decumbent setae, such setae particularly numerous on mesoscutum, mesoscutellum, legs, and metasoma; integument largely without pronounced sculpturing or punctation except faintly and finely imbricate (mesoscutum, in particular, not transversely carinate or striate, with rounded anterior lip); metasoma faintly imbricate (metasoma is partially distorted, i.e., desiccated, and, as such, integument is wavy); posterolateral border of pronotum striate (effectively single row of anteriorly open areolae); posterior border of mesepisternum with single row of areolae, those in ventral half open anteriorly; mesepisternum with row of areolae along anterior border and ventral border, as well as in midtransverse line of upper half (fig. 4); metepisternum with borders composed of open areolae; metanotum areolate; propodeum coarsely areolate; wings clear and hyaline, veins brown.

Head broad, longer than wide, width (across compound eyes) 0.98 mm, length (to apex of clypeus) 0.78 mm; gena narrow, genal width at about midlength 0.20 mm; malar space narrow, short, length less than basal mandibular width; compound eye large, bare, prominent, ovoid, longer than wide, length 0.59 mm, width 0.35 mm, without circumocular carina, inner margins straight and parallel, interocular distance 0.65 mm; ocelli small, arranged in broad triangle on top of vertex above compound eyes, median ocellus separated from lateral ocelli by 1.5 times ocellar diameter, lateral ocelli separated by nearly 3 times their diameter and separated from ocular border by about 2.4× their diameter. Antennal toruli broadly separated, situated slightly below midlength of compound eye; scape short, robust, slightly shorter than first flagellomere; pedicel short, about one-half length of scape; flagellum filiform, with 12 flagellomeres; flagellomeres each longer than wide, individual lengths 2–3× their widths, lengths gradually shortening toward apex of flagellum; apicalmost flagellomere with acutely rounded apex. Clypeus short, with apical margin sinuate. Mandible short, broad, bidentate, subapical tooth broadly triangular. Maxillary and labial palpi short; labial palpus with five palpomeres; maxillary palpus with perhaps five palpomeres (four palpomeres clearly observable; short basal palpomere may be present but difficult to discern).

Mesosoma short and high, length 1.73 mm, maximum height 1.33 mm; pronotum without defined, raised posterior dorsal surface bordering mesoscutum, posterior border broadly concave, lateral surfaces large; prothoracic spiracle covered by rounded knob on posterolateral margin of pronotum; mesoscutum without transverse carinae or striae and with anterior bor- der broadly rounded in profile, with notauli strong, Y-shaped, and percurrent, mesoscutal length 0.98 mm; mesoscutellum arched in profile (fig. 4), medial length 0.40 mm; metanotum subvertical, short, length 0.13 mm; propodeum with distinct dorsal surface, dorsal length (between metanotum and articulation with metasomal petiole) 0.14 mm. Legs long, with slen- der podites; tibial spur formula 1-2-2, spurs prominent; pro- and mesotrochantelli distinct but fused to associated femora; metacoxal groove longitudinal, weakly developed; metacoxa without distal lobe; metatrochanter with dorsolateral groove; metatrochantellus present but somewhat indistinct; metafemur length 1.13 mm, metatibia length 1.15 mm; metabasitarsus elongate but shorter than combined lengths of remaining tarsomeres, metabasitarsus length 0.63 mm, lengths of remaining tarsomeres (from base to apex), 0.25 mm, 0.20 mm, 0.13 mm, and 0.13 mm; pretarsal claws small, simple; arolium small. Forewing (fig. 5A) with pterostigma much longer than wide, tapering gradually in width to acute apex, margin inside marginal cell nearly straight; M+Cu forking distad midlength of Sc+R; M+Cu fork confluent with 1Rs, with distinct 1M lacking (thus discal cell below level of M+Cu); 1 Cua in line with 1cu-a; 1Rs+M straight, shorter than 2Rs+M; 2Rs nearly forming straight line with 2Rs+M, subequal in length to 2Rs+M; r-rs near pterostigmal midlength, elongate, as long as 2Rs; marginal cell broad, elongate, extending nearly to wing apex, with Rs comparatively straight for majority of marginal cell length; rs-m crossveins absent; discal cell narrow, with short, straight 1m-cu giving an inverted (upside down) trapezoidal shape; 2m-cu absent; 2A1 and 2cu-a present as dark infumate veins, demarcating closed subdiscal cell. Hind wing (fig. 5B) without venation except C+R, with three distal hamuli near apical termination of R; without jugal lobe.

Metasoma ovoid in profile, longer than mesosoma, length 1.5× length of mesosoma; tergum I and II fused, forming stocky, triangular petiole, petiole width at articulation with mesosoma 0.10 mm; ovipositor exserted, curved upward, thin, short, length 1.00 mm, length of sheaths 1.05 mm.

Ƌ: Unknown.

HOLOTYPE: ♀ (fig. 3), JZC Bu-551; Cretaceous amber (Cenomanian), Myanmar, Kachin, Tanai Village on Ledo road 105 km NW of Myitkyna; Zigras collection, available through and for permanent deposition in the Division of Invertebrate Zoology , American Museum of Natural History , New York.

ETYMOLOGY: The specific epithet is taken from the Greek mythological prison of the underworld, Tartarus, and the suffix – ikos (– icus) meaning “of ” or “belonging to.”

Subfamily Aulacinae Shuckard, 1841

Tribe Electrofoenini Cockerell, 1917b

Electrofoenini Cockerell, 1917b: 365 . Type genus: Electrofoenus Cockerell, 1917b .

DIAGNOSIS: This group is distinctive relative to its nominate tribe, Aulacini Shuckard, 1841 (= extant Aulacidae , s. str., as used by most contemporary authors), distinguished by following combination of traits: large compound eyes; elongate, projecting mandibles; forewing 2Rs+M elongate; pretarsal claws exceedingly small and simple; presence of a complete occipital carina; percurrent, Y-shaped notauli; and absence of transverse carinae or striae on mesoscutum (except for prominently raised carina along anterior border) (last three traits confirmed only for new genus described herein).

INCLUDED GENERA: Electrofoenus Cockerell, 1917b , and Electrofoenops , new genus, both in Burmese amber.

Figures

FIGURE 3. Microphotograph of right lateral view of holotype female (JZC Bu-551) of Archeofoenus tartaricus, new genus and species, in Cenomanian Burmese amber.

FIGURE 4. Microphotograph of mesosoma of holotype female (JZC Bu-551) of Archeofoenus tartaricus, new genus and species, in left lateral view.

FIGURE 5. Wing venation of holotype female (JZC Bu-551) of Archeofoenus tartaricus, new genus and species (all to the same scale). A. Forewing, with pertinent veins labeled. B. Hind wing.