Oblongomorpha, 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 : 11-12

Oblongomorpha n. gen.

Type species: Oblongomorpha lutetia n. sp., here designated.

Derivatio nominis: The new genus­group name is a reference to the oblong shape of the body. The name is feminine.

Diagnosis: Body oblong, surface areolate. Head very short, protruding little in front of the antennal insertion. No cephalic spines or tubercles. Eyes globular, strongly projecting laterally of the head. Antennae long and thin, first antennal segment 3 to 4 times as long as second, 3rd prolonged, 4th clubbed and covered with dense setae. Labium short, not reaching middle of metasternum. Pronotum with a ring­like vesicular at the anterior margin. Paranota absent. Triangular areolate posterior pronotal process is well developed, extremely elongated backwards along hemelytra covering whole clavi and approximately half of discoidal area. Pronotum with 3 longitudinal carinae. Macropterous form. Outline of hemelytra distinctly sinuate about midlength, apical rounded. Costal and subcostal area inconsicuous. Discoidal occupying nearly 0.54 of hemelytron length. Sutural area (membrane) in broadest place with 11–12 of angled cells. Legs moderately long. Tarsi 2­segmented, with second segment definitely broader and longer than segment I. Upper surface of segment II slightly convex, lower surface flat and covered with bristle­like hairs.

Comments: The development of a cell­like hind outgrowth of the pronotum that completely covers the clavi, a short and broad head, and the absence of additional protruding transverse veins on the hemelytra (plesiomorphic!) clearly classify Oblongomorpha n. gen. in the subfamily Tinginae . The general structure of the antennae and especially the presence of clearly modified second tarsal segment, with bristle­like hairs in a ventral concavity, unequivocally place Oblongomorpha in the tribe Litadeini . Even if the second tarsal segment is not quite as wide as in most of members of the tribe (e.g. Litadea China) it is even elongated and decidedly broader than the first tarsal segment. The decision of describing a new genus for the fossil species instead of including it in the genus Oecharis (only genus among the Litadeini with the same tarsal modification as in the fossil specimen) is mainly based on the absence of clearly prominent cyst formed by the paranota and the general structure of the hemelytra with small cells.

The current classification of this tribe contains 13 extant genera ( Froeschner 2001). So far no representative of the Litadeini has been reported from the fossil record. Lace bugs belonging to the tribe Litadeini range to be Pan­Tropical without exception ( Froeschner 2001).

The oldest representative of the Tinginae (Archepopovia yurii Golub) has yet been recorded from Baltic amber. Judging on the characteristic features of this specimen the subfamily Tinginae with their main features was in the stage of formation during the Eocene ( Golub 2001). Oblongomorpha n. gen. and Chorotingioites n. gen. clearly show that the differentiation of the Tinginae has taken place in this period or even earlier as already supposed by Golub (2001), and Golub & Popov (1999).

A reconstruction of the type species of Oblongomorpha based on the description below is shown in Fig. 11 .

Figures

FIGURE 11. Oblongomorpha lutetia gen. et sp. n., reconstruction of the holotype, (macropterous form), compression fossil; coll. Forschungsinstitut Senckenberg (SMF), Frankfurt am Main (Germany), specimen SMF MeI 10508; scale bar represents 1 mm.