Woldstedtius aureotibialis, Johansson, Niklas, 2020

Johansson, Niklas, 2020, Additions to the Swedish fauna of Diplazontinae (Hymenoptera: Ichneumonidae) with the descriptions of five new species, European Journal of Taxonomy 724, pp. 70-92 : 83-87

Woldstedtius aureotibialis sp. nov.

urn:lsid:zoobank.org:act:5130CD6D-CB68-403E-AF7F-1F76C8E5B558

Figs 9–10

Woldstedtius patei – Klopfstein 2014b: 113 .

Type material

Holotype SWEDEN • ³; Härjedalen , Hede, Synderkölen; 62.294° N, 13.406° E; 5–7Aug. 2016; N. Johansson leg.; Sweepnet along alpine stream/bog; Barcode deposited under GenBank accession number MT268212 ; NHRS-HEVA000011631 .

Paratypes SWEDEN • 1 ♀; Lappland; 10 Aug. (year unknown); C.H. Boheman (1796–1868) leg.; NHRS- HEVA000010749 • 1 ♀; Härjedalen , Hede, Synderkölen ; 62.292° N, 13.405° E; 28 Jul. 2019; N. Johansson leg.; sweepnet along alpine stream/bog; NHRS-HEVA000011632 .

NORWAY • 1 ♀; Oppland, Dovre; C.H. Boheman (1796–1868) leg.; NHRS-HEVA000010750 .

Diagnosis

Woldstedtius aureotibialis sp. nov. ( Figs 9 A–C, 10A–C) is distinguished from Woldstedtius patei ( Dasch, 1964) ( Fig. 11 ) by the orange legs, the less extensive pale colouration of the mesosoma and the less distinct carination of the propodeum ( Fig. 10C ). Woldstedtius patei , known from two specimens collected in the southern part of the Rocky Mountains in North America, has the fore and mid coxae orange, basally infuscate with the apices largely yellow ( Fig. 11 A–C). The hind femur is orange with the inner side infuscate and the hind tibiae are whitish, apically infuscate and with a small subbasal black spot. Furthermore, the yellow shoulder mark, the yellow apices of the scutellum and postscutellum are more extensive in W. patei ( Fig. 11 A–C) while the orange spot on the metapleuron is considerably smaller.

Etymology

The specific epithet aureotibialis (adjective) is derived from the colour of the hind tibia, aureo = golden.

Description

Fore wing length 3.1–4.2 mm. Body length 4.5–5.5 mm. Head in anterior view strongly transverse, central area strongly elevated. Inner orbits almost parallel ( Figs 9B , 10B ). Antennae with 22 flagellomeres. First flagellomere about 5 times as long as wide. Second flagellomere about 3.5–4 times as long as wide. Clypeus in basal third with a transverse swelling, separated from face by a shallow groove. Face evenly and finely coriaceous, matt ( Figs 9B , 10B ). Clypeus with apical margin bilobed, in basal 0.3 distinctly convex. Temple in dorsal view strongly narrowed behind eye. Mesopleuron almost entirely coriaceous, only a small area around mesopleural furrow shining. Sternauli weakly impressed. Epicnemial carina complete, metapleuron strongly coriaceous, matt. Mesoscutum and scutellum evenly and entirely coriaceous. Propodeum strongly coriaceous with only lateral longitudinal carinae present basally, centrally in anterior part with small depression covered by irregular transverse carinae ( Fig. 10C ). Hind coxae coriaceous. Fore wing areolet open, hind wing with three basal hamuli. Metasoma dorsoventrally depressed. Tergites coriaceous, weakly shining. Second tergite basally with longitudinal striae. Third tergite with spiracle slightly above lateral fold. Ovipositor apically truncate.

Colouration of male

Body and head black. Antennae ventrally orange. Scapus yellow ventrally. Face, clypeus, palpi and temple in ventral part entirely yellow. Lower part of propleuron and mesopleuron yellow. Suture between meta- and mesopleuron yellow ( Fig. 9C ). Large shoulder mark, tegulae, subtegular ridge and hind corner of pronotum yellow. Scutellum with small yellow apical spot. Legs orange. Coxae yellow. Hind coxae at base dorsally black and with an irregular black stripe on outer side. Trochanters and trochantelli yellow. Hind trochantelli basally with small black spot. Hind femur on inner side with a large black stripe, which covers almost the entire inner surface. Hind tibia orange, infuscate apically. Hind tarsi infuscate. Metasoma black. Second tergite with a small central yellow spot posteriorly. Third and fourth tergites with large t-shaped yellow spot. Fifth tergite basally yellow ( Fig. 9A ). Laterotergites and parameres yellow.

Colouration of female

The three known females are quite consistent regarding colouration ( Fig. 10 A–C). Body and head black. Tegulae and very small spot on hind corner of pronotum whitish. Palpi yellow. Mandibles yellow with

more or less extensive black mark. Metapleuron basally with large red mark and posterior basal corner on mesopleuron with smaller red mark, the latter may be absent.

Remarks

The taxonomic status of the paratype of Woldstedtius patei from Alaska (1 ♀; Independence Mine; 6 Aug. 1956; W.C. Frohne leg.; USUC) is somewhat uncertain. The orange legs and the slightly weaker carination of the propodeum would suggest that the specimen also belongs to the species here described, but the more abundant pale markings of the coxae and mesosoma are features shared by Woldstedtius patei . It is therefore not included in the type series. Klopfstein (2014b) based the decision to assign the then two known Scandinavian females to W. patei on the study of the Alaskan paratype and was, according to the notes (p. 113), unaware of a second, non-type female from Colorado (1 ♀; Colorado, Mount Evans; 26 Jul. 1964; C. Dasch leg.; 9800’ trap; USUC), thereby overlooking the identity of the species. The morphological differences between W. patei and W. aureotibialis are subtle. The shape and structure of the propodeum is consistent in the three Scandinavian females, which all have the carination of propodeum less distinct ( Fig. 10C ) than in the two Nearctic females, including the holotype, which both have a diamond-shaped area surrounded by weak carinae centrally ( Fig. 11B ). Furthermore, the colouration of the legs, in which the two species differ considerably, is regarded as a stable character in diplazontines, commonly used in species diagnosis and delimitation ( Dasch 1964; Klopfstein 2014b). The phylogenetic analysis places Woldstedtius aureotibialis sp. nov. at a rather basal position within the genus, as sister to a clade including W. flavolineatus and two Neotropical species ( Fig. 1 ).

Ecology

The male holotype and one of the female paratypes were sweep netted between the 5 th and 10 th of August by an open bog with scattered Salix bushes (primarily Salix lapponum L.) surrounding a small stream in an alpine area.

Figures

Fig. 9. Woldstedtius aureotibialis sp. nov., holotype, ³ (NHRS-HEVA000011631). A. Habitus, laterodorsal view. B. Head, anterior view. C. Habitus, lateroventral view.

Fig. 10. Woldstedtius aureotibialis sp. nov., paratype, ♀ (NHRS-HEVA000011632). A. Habitus, lateral view. B. Head, anterior view. C. Propodeum, dorsal view. Photos: Alexander Berg.

Fig. 11. Woldstedtius patei (Dasch, 1964), holotype, ♀, Colorado, Grand L., 24 Aug. 1940, H. and M. Townes leg. (USUC). A. Habitus, lateral view. B. Propodeum, laterodorsal view. C. Head and mesosoma, lateral view. D. Labels. Photos: David Wahl (USUC).

Fig. 1. Bayesian phylogenetic reconstruction based on a four-gene dataset from Klopfstein et al. (2011). The two new taxa Homotropus klopfsteinae sp. nov. and Woldstedtius aureotibialis sp. nov. were included in the dataset by their barcoding region (CO1). Values next to nodes are posterior probabilities, with asterisks representing maximum clade support.