Pronymphes hoffeinsorum, Archibald, Bruce, Makarkin, Vladimir N. & Ansorge, Jörg, 2009

Archibald, Bruce, Makarkin, Vladimir N. & Ansorge, Jörg, 2009, New fossil species of Nymphidae (Neuroptera) from the Eocene of North America and Europe, Zootaxa 2157, pp. 59-68 : 63-66

Pronymphes hoffeinsorum sp. nov.

Figs. 2 –4

Etymology. The specific epithet is formed from the surname of Christel and Hans-Werner Hoffeins, in recognition of their contributions to amber research.

Holotype. Specimen BaB 1544 - 2, collected by Christel and Hans-Werner Hoffeins, deposited in SDEI. An incomplete, crumpled insect in a yellow, translucent piece of amber: distal portion of abdomen; distal two third of left forewing, covered by a partial left hind wing; fragmentary right fore- and hind wings overlapping. Syninclusions include stellate hairs and nemathelminthes.

Type locality and horizon. Baltic amber (Yantarny [=Palmnicken], Kaliningradskaya Oblast’, Russia); Priabonian.

Diagnosis. Forewing separable from that of P. mengeana by fork of M located much distally, only slightly proximal to origin of Rs1 [far proximal to origin of Rs 1 in P. mengeana ].

Description. Distal portion of abdomen (preserved portion 4 mm long); terminal, genitalic segments obscured, probably female judging from prolonged laterally 8th tergite (Fig. 4).

Forewing. Maximal preserved length of left forewing 12.1 mm (estimated length about 19 mm), 5.5 mm wide. Wing margin with distinct trichosors: one between tips of each two veins along apical margin; three to four between tips of veinlets/veins (one between branches of shallow marginal forks) along costal, hind margin. Each vein/veinlet tip thickened like trichosors. Macrotrichia along veins rather long. Costal space relatively narrow, dilated towards base. Subcostal veinlets bent, simple medially, shallowly forked distally. Sc+R1 entering margin nearly at apex; proximal four veinlets of Sc+R1 shallowly forked, next three veinlets deeply dichotomously branched; no crossveins preserved between veinlets of Sc+R1. Subcostal space rather broad, no crossveins. R1 space broaden towards base, with eight crossveins arranged rather regularly between origin of Rs1, fusion of Sc; R1, long hypostigmal cell, three crossveins distal to it. Rs with eight branches, not or few branched distally. Rs1 origin far distant from wing base, with only very shallow marginal fork. M forked slightly proximal to origin of Rs1. MA with two distal branches, shallowly forked. MP with three branches: proximal-most deeply forked, two next shallowly branched; between these branches one crossvein. MP space small, triangular, enclosed by distal portion of MP, basal-most branch of MP. Radial, medial crossveins numerous; crossveins in distal portion of radial space forming outer gradate series. Between MP, CuA several crossveins. CuA occupying relatively small space, with five irregular branches, shallowly to deeply branched; each branch connecting by crossvein to other (four crossveins in total, one in left forewing anomally incomplete). CuP pectinately branched, with simple branches, not connecting by crossveins. Membrane hyaline, without pattern.

Hind wing without distinct tornus; 8.1 mm long as preserved (estimated length about 18 mm), 4 mm wide as preserved (estimated length about 4.5 mm). One to four distinct trichosors between each two veins along preserved apical, hind margins. Venation of apical-most portion of hind wing similar to that of forewing. R1 space rather broad in middle portion, with crossveins arranged rather regularly. Rs with three preserved branches. Rs1 origin far distant from wing base, slightly proximal to end of CuA. Preserved MA straight, with one or two branches distally. MP with five branches, one simple, other forked; between some branches one crossvein (three crossveins preserved totally). MP space triangular, small, enclosed by distal portion of MP, basalmost branch of MP. Radial, medial crossveins numerous. Between MP, CuA several crossveins. CuA pentinately branched (seven branches preserved), not connected by crossveins. CuP, anal veins not preserved. Membrane hyaline, without pattern.

Comments. Judging from Pictet-Baraban and Hagen’s original description and figure (1856: Pl. 8, Fig. 15) and the redescription of Krüger (1923), Pronymphes mengeana is represented by a possibly incomplete body and the basal half of both right wings. Its type seems to be lost. Unfortunately, mainly the proximal parts of the wings of P. mengeana and the distal parts of P. hoffeinsorum are preserved. In spite of this, there is enough available comparative venation to strongly associate these as congeners and to confidently distinguish them as separate species. Given the incomplete nature of these specimens, placement of the new species in Pronymphes remains tentative.

The forewing of P. mengeana was estimated by Krüger (1923) as 27 mm long under the assumption that the 9 mm of preserved portion was a third of its complete length. However, comparing this with wings of modern species we find it more reasonable to assume that the preserved portion actually represents about half its complete length, in which case the wing would have not exceeded 20 mm long.

We conclude from analysis of P. hoffeinsorum and published figures of P. mengeana that the genus is valid, and that Pronymphes belongs to Nymphes- group (see above). MacLeod (1971) argued in favor of a close affinity between Pronymphes and Nesydrion . The venation of these genera is indeed similar, but not identical (see diagnosis of the genus Pronymphes , note comparisons of crossveins in the subcostal space and between branches of CuA in the forewing and branches of MP is the hind wing). Moreover, Pronymphes is smaller than any species of Nesydrion : the minimal forewing length in Nesydrion (i.e., N. diaphanus Gerstaecker, 1885 ) is 23 mm ( New 1982).

FIGURE 4. Apex of abdomen of Pronymphes hoffeinsorum sp. nov., holotype specimen BaB 1544 -2. 8T, 8th tergite. Scale bar = 1 mm.

Figures

FIGURE 2. Pronymphes hoffeinsorum sp. nov., photographs of holotype specimen BaB 1544 - 2. A, specimen as preserved. B, left wings (mainly the forewing visible). Scale bar = 2 mm.