Exmesselensis, 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 : 4-6

Exmesselensis n. gen.

Type species: Exmesselensis disspinosus n. sp., here designated.

Derivatio nominis: The new genus­group name is derived from ex (Latin, meaning “out of”), plus the name of the type locality Messel. The name is masculine.

Diagnosis: Small specimen, ca. 2.5 mm. Body moderately oblong­oval. Head elongated, with one significant interocular (dorsomedial) tubercle. Bucculae elongated forward. Eyes globular, strongly projecting laterally of the head. Antennae thin, 3rd segment long: just a little shorter than body width (relation 0.91). Pronotum more or less trapezoid, with 3 longitudinal carinae; posterior margin concave. Paranotum narrow. Scutellum completely exposed, triangular. Hemelytra distinctly subdivides by raised veins into costal, subcostal, discoidal, and sutural areas. Stenocostal area absent. Clavus well expressed.

Comments: The new genus Exmesselensis combines some morphological characters of the Cantacaderinae and the Tinginae . The features of Cantacaderinae, in particular Phatnomini, includes: (1) the absence of stenocostal area of hemelytra (unfortunately it was impossible to examine in detail the scent gland openings and the morphology of the peritrema), (2) presents of only one dorsomedial (interocular) tubercle (completely absent in Cantacaderini and characteristic for Phatnomini), (3) the absence of a well expressed posterior triangular projection of the pronotum, (4) the exposed scutellum, (5) bucculae elongated forward and not touching anteriorly, and (6) clavi clearly separated by Pcu from corium by commissural.

The absence of additional transverse veins in the discoidal area on the other hand is a characteristic feature of the majority of Tinginae contrary to Cantacaderinae in which they are usually well expressed in different degree, especially in Phatnomini ( Froeschner 1996).

Among those genera of the Phatnomini bearing a dorsomedial tubercle, habitually, the fossil genus Exmesselensis n. gen. is superficially quite similar to the living lace bug of the genus Distocader Froeschner. It shares in particular the head and antennal structure with the former. Exmesselensis n. gen. is distinguished from this endemic genus by relative broader pronotum, shorter carinae of the pronotum (majority of the Phatnomini show a 1­ carinated pronotal disc), and the absence transverse veins in the discoidal area (this affiliates the fossil genus with the Phatnomini genera Pullocader Pericart , Ulmus Distant , and Zetekella Drake ).

Nevertheless, the incomplete state of material, however, does not permit an evaluation of its closer relationships at the present. A reconstruction of the type species of Exmesselensis based on the description below is shown in Fig. 2 .

The distribution of the extant representatives of the Phatnomini today is restricted to the southern hemisphere. The majority of the 26 described, extant genera are distributed in the Oriental and Ethiopian zoogeographic regions ( Froeschner 1996). For instance, Distocader , represented by only a single species, is only known from New Guinea ( Drake & Ruhoff 1965b).

Furthermore Exmesselensis shows once more those representatives of the Cantacaderinae were much more significant in the Paleogene fauna and wide­spread in Europe than today. In particular some genera of the Eocene European Phatnomini (e.g. Intercader Golub & Popov, Tingicader Golub & Popov, Exmesselensis n. gen.) show morphological similarities to the advanced subfamily Tinginae .

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.