Sorellevania guillami, JOUAULT, 2023

JOUAULT, CORENTIN, 2023, The second species of Sorellevania Engel, 2006 (Evanioidea: Evaniidae) from the mid-Cretaceous Burmese amber, Palaeoentomology 6 (1), pp. 3-7 : 4-5

Sorellevania guillami sp. nov.

( Figs 1 , 2 )

urn:lsid:zoobank.org:act:E1F43A04-572A-4529-88DA-9D56A1F817BA

Material. Holotype, IGR.BU-065 (a nearly complete specimen preserved in a squared piece of amber measuring 6 × 6 × 1 mm), deposited in the amber collection of the Geological Department and Museum of the University of Rennes, France (IGR).

Etymology. The specific epithet honors my friend Elvis Guillam, and is treated as a noun in a genitive case.

Diagnosis. Antenna with 12 flagellomeres. Forewing with distal abscissa of R not fully tubular, tubular part ending before marginal cell apex; 2r-rs located near mid-length of second submarginal cell (= 3-Rs long); 1-Cu and 1-Rs of similar length; first medial cell wide; 1m-cu short and tubular (= Rs+M and Cu clearly separated); 1rs-m crossvein spectral; 4-M long reaching apex of marginal cell. Hind wing with three hamuli.

Type locality and horizon. Noije Bum Hill , Hukawng Valley , Kachin State, Myanmar; upper Albian to lower Cenomanian, mid-Cretaceous .

Description. Female fully winged and of small body size (total body length, from apex of mandibles to apex of the metasoma but without ovipositor approximately 1.42 mm).

Head slightly wider than long (ca. 0.43 mm long); vertex broad, concave beyond ocelli; ocelli present; compound eyes relatively small, length less than one-half head length, well separated from vertex and ocelli; malar space slightly longer than basal mandibular width; left mandibles with a small, sharp basal tooth, a larger triangular first marginal tooth, a deep incision between first marginal and apical teeth, a broad apical tooth basally convex than acute; clypeus swollen medially and distinctly elevated above plane of face; gena narrower than maximum width of compound eye; antenna elbowed, articulated slightly above level of head midlength, not inserted on swelling or shelf; scape elongate, ca. 0.28 mm long and maximal width ca. 0.06 mm; pedicel slightly longer (ca. 0.08 mm long) than wide (ca. 0.05 mm wide), subequal to first flagellomere article; flagellomeres each longer than wide, thickening toward apex; distalmost flagellomere tapered, ca. 0.18 mm long; occipital carina present and complete.

Mesosoma strongly sclerotized, compact and relatively high, ca. 0.47 mm high (measured above procoxa), shorter than head length; pronotum without distinct dorsal surface, collar distinct; mesoscutum slightly arching above level of head in lateral aspect giving species a slightly “hunchbacked” appearance; mesoscutellum strongly arched; propodeum posteriorly sculptured (sculpture hardly describable), laterally with relatively regular areolae; propodeum not rising toward articulation with petiole. Legs elongate; tarsi pentamerous; pretarsal claws short, slender, simple; arolium present; foreleg and midleg hardly measurable; hindleg the longest (all lengths in mm) with femur ca. 0.59 mm, tibia ca. 0.53 mm, first tarsomere ca. 0.20 mm, second ca. 0.17 mm, third ca. 0.13 mm, fourth ca. 0.11 mm, fifth ca. 0.11 mm.

Forewing ca. 1.20 mm long and ca. 0.38 mm wide, venation relatively complete, with seven cells enclosed by tubular or spectral veins; pterostigma elongate and narrow, narrower than distal width of costal space; M+Cu fork anteriad 1cu-a; 1-M longer than 1-Rs; 1-Cu shorter than 1cu- a; first medial cell pentagonal longer than wide, fully enclosed by tubular veins; Rs+M shorter than 1-M; 2-Rs basally not sclerotized, subequal to 1-M; crossvein 2r-rs long, straight and vertical, longer than 1-Rs; first submarginal cell quadrate, longer than wide; marginal cell triangular, about 2.5× longer than wide; 3-Rs slightly longer than 1-Rs; 4-Rs long slightly curved distad its mid-length; second submarginal cell longer than wide, not fully enclosed by tubular vein; 1rs-m crossvein spectral, apparently longer than 1m-cu; 4-M nearly straight, long (reaching apex of marginal cell), and ending freely in wing membrane; A tubular, not touching straight 1cu-a; 3- Cu spectral; 4-Cu less sclerotized than other vein, straight, ending freely in wing membrane distad 1rs-m.

Hind wing ca. 0.58 mm long, with three distal hamuli; without venation except Sc+R; with long, sparse, wellseparated setae along posterior wing margin; without jugal lobe.

Metasoma rounded, narrower close to petiole; petiole ca. 0.20 mm, tubular, and curved distally; length of other segments combined ca. 0.45 mm; ovipositor long (at least 0.53 mm long) and thin, acute distally.

Figures

FIGURE 1. Sorellevania guillami sp. nov., holotype IGR.BU-065. A, Habitus in right lateral view. B, Habitus in left lateral view (arrows pointing each flagellomere). Scale bars = 0.5 mm.

FIGURE 2. Sorellevania guillami sp. nov., holotype IGR.BU-065. A, Detailed view of the head in right lateral view (arrows pointing to the teeth). B, Detailed view of the metasoma in right lateral view. C, Detailed view of the forewing venation with names of veins labelled. Scale bars = 0.25 mm.