Exmesselensis disspinosus, Wappler, Torsten, 2003

Wappler, Torsten, 2003, New fossil lace bugs (Heteroptera: Tingidae) from the Middle Eocene of the Grube Messel (Germany), with a catalog of fossil lace bugs, Zootaxa 374, pp. 1-26 : 6-8

Exmesselensis disspinosus n. sp. ( Fig. 2–6 )

Derivatio nominis: The specific epithet is derived from the Latin words dis (meaning “without”) and spinosus (meaning “thorny”) and is a reference to the absence of conspicuous head spines.

Holotype: A complete individual, dorsoventrally compressed, coll. Forschungsinstitut Senckenberg ( SMF), Frankfurt am Main ( Germany), specimen SMF MeI 6301 ( Fig. 2–4 ).

Paratypes: SMF MeI 6958 (laterally compressed), SMF MeI 7798 (dorsoventrally compressed), SMF MeI 7877 (dorsoventrally compressed), SMF MeI 7920 (dorsoventrally compressed), SMF MeI 8082 (dorsoventrally compressed).

Dimensions (in mm): Body length 2.56, width 1.08; length of head (from apex of clypeus to posterior margin of pronotum) 0.93, width 0.63; interocular width 0.26; antennomeres 2­4: 0.16, 0.99, 0.46; length of pronotum 0.83, width 1.36; length of fore leg (SMF MeI 6958): femur 0.69, tibia 0.99 (incomplete); length of middle leg (SMF MeI 6958): femur 0.79; length of hind leg (SMF MeI 6958): femur 0.96, tibia 1.19.

Type locality: Grube Messel near Darmstadt, grid square E89.

Stratigraphical and geographical distribution: Known only from the lower Middle Eocene (Lower Lutetian, ELMA Geiseltalian, MP11), Messel Formation; 2.57 –3.09 m over alpha.

Diagnosis: As for the genus (see above).

Description: Small specimen, ca. 2.5 mm. Body oblong­oval, 2.3 times longer than wide, dorsal and ventral side of the body black to dark­brown, legs and antennae lightbrown posterior.

Head elongated, 1.47 times as long as wide (from clypeus to anterior margin of pronotum). Vertex between eyes slightly elevated. Eyes globular, strongly projecting laterally of the head. Head with one significant interocular (dorsomedial) tubercle. Antenniferous tubercles short (half as long as the first antennal segment) and oblique diverge, with their apex thin and slightly curved. Antennae long and thin, especially the 3rd is 2.66 times longer than the 4th. First two segments very short. Bucullae distinctly protruding beyond the apex of the clypeus, directed to each other posteriorly, and not touching anteriorly.

Pronotum 1.63 times wide as long, covered with rough punctuation. Pronotal disc perceptible convex, with 3 longitudinal carinae. Median carina stretching from a posterior margin to the middle of the pronotum. Lateral carinae nearly as long as the median carinae, and weakly curved. Anterior margin of pronotum weakly waved, anterior margin medially strongly concave, anterolateral angles rounded. Paranota with one row of medium size cells of irregular and round form, getting gradually smaller to the anterior margin. Scutellum completely exposed, triangular in shape.

Hemelytra (macropterous form) surpassing apex of abdomen, flattened, with distinctly carinated veins, separating the hemelytra in costal, subcostal, discoidal, and sutural areas.

Lateral margins right in the midst imperceptible broadened, and slightly narrowed at base. Costal and subcostal area not wide, each with two rows of cells, and in the last third only with one row. Discoidal area triangular in shape, and in the widest place with 6­7 incompletely regular rows of cells of mainly oval shape. Sutural area (membrane) along clavus with one row of cells, and apical the clavus the sutural area is extremely widened forming the areolate membrane which consists in the broadest place of approximately 12–14 irregular rows of cells of round to oval shape. Tips of sutural areas of both hemelytra fully overlapping at rest. Clavus triangular in shape, and clearly separated by a claval commissure from the corium. In the broadest place with 4(?) rows of cells of mainly oval shape. In regard to the bad preservation the hypocosta is probably 1­serated (SMF MeI 7877, 7798). Femora anterior slightly swollen. Tibiae straight and cylindrical. Tarsi 2­segmented (?).

Figures

FIGURE 2. Exmesselensis disspinosus gen. et sp. n., reconstruction of the holotype, (macropterous form), compression fossil; coll. Forschungsinstitut Senckenberg (SMF), Frankfurt am Main (Germany), specimen SMF MeI 6301; scale bar represents 0.5 mm.

FIGURE 3 – 6. 3, Dorsal habitus of holotype of Exmesselensis disspinosus (SMF MeI 6301); 4, Detail of areolate hemelytra of E. disspinosus (SMF MeI 6301); 5, Lateral habitus of paratype (SMF MeI 6958); 6, Detail of head and antennae structures (SMF MeI 6958).