Sympherobius completus, Makarkin, Vladimir N. & Wedmann, Sonja, 2009

Makarkin, Vladimir N. & Wedmann, Sonja, 2009, First record of the genus Sympherobius (Neuroptera: Hemerobiidae) from Baltic amber, Zootaxa 2078, pp. 55-62 : 56-59

Sympherobius completus sp. n.

( Figs. 1–3 )

Diagnosis. This species may be easily distinguished from others of the genus by the following forewing character states [alternative character states are given in brackets]: (1) crossvein 3rs3-rs2 present, located distally, connecting Rs3, Rs2 [absent in many species, or strongly shifted proximally in other species connecting R (or Rs) with Rs2 (see comments below)]; (2) crossvein 3rs2-rs1 located far distally relative to next crossveins of the series [proximally to slightly distally in other species]; (3) two crossveins 4rs-rs3, 4rs3- rs2 located distally to primary forks of Rs3, Rs2 [proximally in vast majority of other species].

Description. Head prolonged in lateral view. Antennae: scape rather large; pedicel smaller than scape but larger than first flagellar segments; left flagellum 44-segmented, right flagellum 45-segmented. Maxillary palpi 5-segmented, labial palpi 3-segmented, both slender; apical 6th and 4th pseudo-segments respectively strongly slender, acute. Pronotum short. Femora of all legs markedly swollen. Leg measurements (where confident by preservation): right foreleg: femur 0.56 mm, tibia 0.56 mm, tarsus (complete) 0.52 mm, basitarsus 0.2 mm; right midleg: femur 0.68 mm, tibia 0.76 mm; right hindleg: femur 0.88 mm, tibia 1.36 mm, tarsus 0.48 mm, basitarsus 0.2 mm. Left foreleg: femur 0.6 mm, left midleg: tarsus 0.44 mm, basitarsus 0.18 mm; left hindleg: femur 0.92 mm, tibia 1.32 mm, tarsus 0.48 mm, basitarsus 0.2 mm. Abdominal terminalia constructed typically for female Sympherobius . 9th gonocoxites (=gonapophysis lateralis) bears distinct stylus. Body length (head to apex of abdomen) 4 mm.

Forewing oval with rounded apex, 5.5 mm long, 2.4 mm wide. Trichosors prominent along entire wing margin. Costal space very wide, broader basally. Majority of prestigmal subcostal veinlets branched once or twice; stigmal subcostal veinlets simple. Humeral veinlet (i.e., basal-most subcostal veinlet) recurrent, pectinately branched, with four branches (three short, simple and one longer, forked). True crossveins lacking in costal space. Subcostal space moderately wide for entire length, with two crossveins (basal 1sc-r, distal 3sc- r). R1 forked apically, with one branch forked once. R1 space normal in width with comparison to other species of genus. Three separate branches originated from R [=ORB’s, see Material and Methods]; ORB1[=Rs1], ORB2 [=Rs2] configuration very similar, not forked proximal to fourth gradate series; ORB3 [=Rs proper] possesses two branches, originating proximal to third, fourth gradate series (Rs3, Rs4 respectively). M appears fused basally with R1 for some distance. M forked proximal to second gradate series; MA, MP parallel before terminal branching. CuA pectinately branched, with three branches, all of which have marginal forks. CuP with only one marginal fork. 1A with two simple pectinate branches. 2A deeply forked; proximal branch probably simple (not seen clearly due to recurvature of anal region), distal branch with three very short simple pectinate branches. 3A probably simple (not clearly preserved). Four gradate series of crossveins (series 1-4 of Oswald 1993) posterior to R1. First series consists of four crossveins: 1m-cu, 1cu-a1, 1a1-a2, 1a2-a3; an additional [aberrant?] crossvein seems be located basad of 1a2- a3, indistinctly visible in left forewing only (in right forewing this area cannot be seen). Second series includes three crossveins: 2r-m, 2m-cu, 2icu. Third (‘inner’) series with six crossveins (from 3r1-rs to 3m-cu); 2rs2-rs1 shifted far distally relative to next crossveins in the series. Fourth (‘outer’) series incomplete, with four crossveins (from 4r1-rs to 4rs2-rs1). Crossveins absent between branches of CuA. Wing without markings, slightly fuscous.

Hind wing 4.5 mm long, about 1.7 mm wide. Trichosors prominent along entire margin. Crossvein 1r1-rs short. Basal crossveins r-m connecting M with Rs1. Two crossveins in inner gradate series, none in other. M forked slightly distal to origin of most proximal branch of CuA, slightly proximal to origin of Rs2. CuA with four branches, each forked.

Holotype. Female specimen GZG. BST.5245, deposited in GZG. Old labels: “B[ernstein]. S[ammlung]. d[er]. Univers[ität]. Koenigsberg i[n]. Pr[eussen].”; “N 21”; “5245” “5871”.

Locality and horizon. Baltic amber (precise collecting site unknown, probably near present-day Kaliningrad). Middle/ Late Eocene.

Etymology. From Latin completus , complete, in reference to the complete third (‘inner’) series of gradate crossveins.

Remarks. An undescribed hemerobiid specimen from Baltic amber ( Weitschat & Wichard 1998: Pl. 56, Fig. e) most probably belongs to this species judging from its forewing venation, which possesses all of the diagnostic features of Sympherobius completus sp. n.

Figures

FIGURES 1 – 2. Sympherobius completus sp. n. Holotype GZG-BST- 5245, lateral view of the specimen. 1, left side; 2, right side. Scale bar = 1 mm.

FIGURES 3 – 4. Sympherobius completus sp. n. Holotype GZG-BST- 5245, wing venation. 3, left forewing (converted to standard right dorsal view); 4, right hind wing. Scale bar = 1 mm.