Symphrasites, Wedmann & Makarkin, 2007

Wedmann, Sonja & Makarkin, Vladimir N., 2007, A new genus of Mantispidae (Insecta: Neuroptera) from the Eocene of Germany, with a review of the fossil record and palaeobiogeography of the family, Zoological Journal of the Linnean Society 149 (4), pp. 701-716 : 704-705

GENUS SYMPHRASITES GEN. NOV.

Etymology: Symphras- (from Symphrasis , a mantispid genus-group name) + -ites (a traditional suffix of fossil genera), in reference to the symphrasine affinity of the genus. Gender masculine.

Type species: Symphrasites eocenicus sp. nov.

Included species: The type species only.

Diagnosis: In forewing MP deeply forked (17); trichosors present at most in apical portion of wing (18); R1 comparatively long (19); CuP deeply forked once (20); crossvein 2r-m present, connecting Rs1, MA proximal to gradate series of crossveins (21).

Remarks: We are confident of the placement of this genus in Symphrasinae , as it possesses important forewing diagnostic character states of this group (5)– (7), (9), and (10) (see diagnosis of the subfamily above). Some character states are not, however, available in the examined specimen [i.e. (8), (11), and (12)], as the basal portion of a wing is either lacking or strongly folded. In some other ways Symphrasites gen. nov. differs quite strongly from other known genera of the subfamily. Interestingly, a number of the character states of Symphrasites are derived with regard to the states of extant genera [characters (17), (18), and (20), see below].

Character state (17): MP is never deeply forked in any species of Mantispidae ; this is undoubtedly an autapomorphy of the genus/species. Alternatively, this may be an anomaly of this specimen. Only other specimens will resolve this.

Character state (18): The trichosors are present in all examined extant species of Symphrasinae . They are, however, sometimes not distinct, and therefore may be difficult to detect in impression/compression fossils. In any case, the appearance of trichosors in S. eocenicus is clearly less distinct than in most of the extant species.

Character state (19): In all examined species of the extant Symphrasinae , R1 enters the wing margin well before the apex; in S. eocenicus it enters more distad, almost near the apex. The condition of R1 entering the wing margin near the apex may be considered plesiomorphic, as it also occurs in Liassochrysa and Promantispa .

Character state (20): The structure of CuP in Symphrasites most resembles that of some species of Anchieta and Trichoscelia , where CuP is deeply forked once. However, the closely spaced branches of CuP as found in S. eocenicus do not occur in either Anchieta or Trichoscelia . In the other extant Symphrasinae , one of the branches of CuP is forked again, or the fork of CuP is not so deep, and its branches are not clearly parallel.

Character state (21): Crossvein 2m-r is absent in other species of Symphrasinae (as well as in the vast majority of other mantispids), and its presence in Symphrasites may be considered either as a plesiomorphy or as an autapomorphy of the genus. 2m-r also occurs in the Jurassic Liassochrysa , Promantispa and the extant Ditaxis , but in these genera 2m-r is a part of the inner, more basally located, gradate series of crossveins continuing from Rs to CuP (in Promantispa this series is incomplete). So, it is reasonable to assume that the crossvein 2m-r in these genera and Symphrasites appeared independently.

SYMPHRASITES EOCENICUS SP. NOV.

( FIGS 2–4 )

Etymology: From the Eocene, in reference to the age of the type specimen.

Holotype: Specimen MeI 8384, deposited in FIS. An incomplete, partly folded, well-preserved forewing.

Type locality and horizon: Messel pit near Darmstadt , Hesse, Germany; grid square E8/9. Messel Formation, lower Middle Eocene (lowermost Lutetian, MP 11 ), from +0.575 to + 0.77 m above local marker horizon alpha .

Diagnosis: Same as for Symphrasites gen. nov.

Description: Forewing with rounded apex, c. 14–15 mm long (estimated, 12 mm preserved), c. 5.6–5.7 mm wide (estimated, 4.5 mm preserved). Trichosors present but indistinct, restricted mainly to apicalmost portion of wing margin ( Fig. 4 ). Costal space narrowed towards wing apex. Subcostal veinlets simple, straight, oblique, and widely spaced. Sc stout, appears atrophied after distal subcostal crossvein (3sc-r), apparently entering wing margin within pterostigma. Pterostigma distinct, pale, strongly haired, situated between R1 and costal margin; incorporated veinlets almost invisible, rows of macrotrichia not distinct. Subcostal space rather narrow, not dilated towards apex; three crossveins detected: two intermediate (2sc-r), closely spaced, situated after origin of Rs, one distal (3sc-r). R1 entering margin slightly before wing apex, with at least eight veinlets distal to pterostigma, all forked. Space between R1 and costal margin distal to pterostigma comparatively broad. Origin of Rs far removed from wing base. R1 space rather narrow, with two rather short crossveins. Rs with 11 branches, all forked (mainly deeply). Single gradate series of crossveins continuing from most distal branch of Rs to CuP, with 14 crossveins. Crossvein 1r-m connects stem of Rs apparently with stem of M slightly proximal to primary fork; crossvein 2r-m present, connects Rs1 and MA. Origin of M not preserved; basalmost parts of MA and MP diverged at angle more than 45°, distal to origin of Rs; MA straight before gradate series, twice forked distally; MP deeply forks slightly distal to crossvein 2m-cu, so MP has two long branches, each of which forked twice distally. Origin, primary forking of Cu not preserved. CuA with comparatively few branches, apparently with three branches. CuP deeply forked once, its branches closely spaced, nearly parallel. Anal area very crumpled. Wing membrane without maculation.

Remarks: The two closely spaced intermediate crossveins in the subcostal space (both named here 2sc-r) may present an anomaly caused apparently by the duplication of this crossvein. Such duplications often occur, for example, in the Hemerobiidae (e.g. Makarkin, 1995), but apparently were not reported hitherto in the Mantispidae . On the other hand, this part of the wing is not well preserved, and it is very difficult to discern the more basal vein 2sc-r in the fossil (compare Fig. 3 ).

Figures

Figure 2. Symphrasites eocenicus gen. et sp. nov., holotype MeI 8384. A, photograph. B, drawing of the forewing. Scale bar = 1 mm.

Figure 3. Symphrasites eocenicus gen. et sp. nov. Reconstruction of the forewing venation of the holotype FIS MeI 8384. All unassignable veins are omitted in the drawing. C, costa; CuA, anterior cubitus; CuP, posterior cubitus; MA and MP, anterior and posterior branches of media; pt, pterostigma; R, radius; R1, first branch of radius; Rs, radial sector; Sc, subcosta. Scale bar = 1 mm.

Figure 4. Apical portion of forewing margin of Symphrasites eocenicus showing trichosors (arrows). Scale bar = 100 µm. Laser scanning photograph.