Homotropus riedeli, 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 : 80-83

Homotropus riedeli sp. nov.

urn:lsid:zoobank.org:act:015B88D4-B3AA-4A41-B694-425A00662113

Figs 7–8

Diagnosis

Separated from all other species of Homotropus primarily by the unique colour pattern with the legs, metasoma and antennae almost entirely red and the mesosoma with extensive red markings ( Fig. 7 ).

Also distinguished by the strong sculpture and carination of the propodeum ( Fig. 8 B–C). Perhaps superficially most similar to Homotropus haemorrhoidalis Szépligeti, 1898 , but that species has a slightly different colouration with for example the antennae and most of metasoma black and all coxae orange. Furthermore, the apical flagellomeres have short thick bristles in H. haemorrhoidalis and the propodeum has less prominent carinae.

Etymology

The specific epithet riedeli (masculine name in genitive case) is in honour of Matthias Riedel (Bad Fallingbostel, Germany), for his contributions to the systematics of ichneumonid wasps.

Type material

Holotype SWEDEN • ♀; Skåne, Ystad, Kåseberga ; 55.385° N, 14.066° E; 17 Jul.–14 Sep. 2013; N. Ryrholm and C. Källander leg.; MV-light trap in warm coastal sandslopes; NHRS-HEVA000011630.

Description

Female

Fore wing length 5.0 mm. Body length 6.9 mm. Head transverse in anterior view. Inner orbits almost parallel. Face entirely coriaceous and matt ( Fig. 8A ). Clypeus with apical margin bilobed and thin. Clypeus in basal 0.66 weakly convex. Antennae with 20 flagellomeres. Head behind eyes strongly narrowed. Temple in lateral view about 0.3 times as wide as compound eye. Mesopleuron centrally anteriorly with shallow punctures. The interstices about equal to diameter of punctures. In lower part, punctures become indistinct against coriaceous background. In upper part, punctures partly fading to irregular, almost rugose sculpture ( Fig. 8C ). Area around mesopleural furrow polished without punctures. Metapleuron coriaceous, shining. Mesoscutum shining with weak microsculpture between punctures, centrally becoming more strongly coriaceous. Scutellum weakly coriaceous with distinct punctures, interstices between punctures slightly larger than diameter of punctures. Propodeum strongly irregularly rugose, with area petiolaris and indicated area superomedia delimited by strong, irregular carinae ( Fig. 8B ). Indicated area superomedia with surface covered with irregular transverse carinae. Coxae coriaceous, matt. Fore wing with areolet closed and vein 3rs-m pigmented ( Fig. 7 ). Metasoma laterally compressed from 4 th tergite. First tergite strongly longitudinally striate. Second tergite strongly coriaceous with weak striation basally. Third tergite polished with weak microsculpture, in basal half coriaceous and matt. Tergites 4–7 polished with weak microsculpture. Spiracle of second tergite above lateral fold and on third tergite on lateral fold.

COLOURATION. Body and head black. Antennae reddish brown. Scapus brown, fading to brownish yellow ventrally. Clypeus, mandibles except mandibular teeth, palpi and large central face patch yellow. Face below antennal sockets dark reddish brown. Lower part of mesopleuron, metapleuron and a large spot on propodeum laterally orange. Scutellum orange. Large shoulder mark, subtegular ridge, tegulae, hind margin of mesopleuron and large spot at the hind corner of pronotum yellow. Legs orange. Fore and mid coxae yellow, orange basally. Trochanters and trochantelli on fore and mid leg yellow. Hind trochanter and trochantelli with large yellow spot. Hind legs apart from trochanter and trochantelli, entirely orange. Metasoma orange. First tergite centrally black with lateral and apical margins widely orange. Tergites 7 and 8 black.

Male

Unknown.

Ecology

The only known specimen was collected by a MV-light trap placed in an area characterized by warm steppe-like sandy heaths and herb-rich coastal slopes at the southern tip of Sweden. The female was collected between the 7 th of July and the 14 th of September.

Figures

Fig. 7. Homotropus riedeli sp. nov., holotype, ♀ (NHRS-HEVA000011630). Habitus, lateral view.

Fig. 8. Homotropus riedeli sp. nov., holotype, ♀ (NHRS-HEVA000011630). A. Head, anterior view. B. Propodeum, posterodorsal view. C. Mesosoma, lateral view.