Ophion costatus Ratzeburg 1848
Creators: name: Johansson, Niklas
name: Cederberg, Björn
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Ichneumonidae
Ophion
Ophion costatus

description: Ophion costatus Ratzeburg, 1848
Figs 7G, 8H, 10B, 47 A–B
Ophion costatus Ratzeburg, 1848: 79–80.
Material examined
82 ♀♀, 17 ♂♂ (Sweden); 2 ♂ (Great Britain); 1 ♀ (Germany); 1 ♂ (Hungary); 2 ♀♀ (Norway); 3 ♀♀ (Lithuania).
Diagnosis
Fore wing length (15) 17–19 mm. Antenna with 48–55 flagellomeres. First flagellomere 4.0 times as long as wide. Second flagellomere about 2.0 times as long as wide. Central flagellomeres about 1.5–1.6 times as long as wide. Apical flagellomeres approximately 1.5 times as long as wide. Flagellomeres in females, less so in males, with rather long prominent pilosity. Length of pilosity about 0.5 width of flagellomere (Fig. 8B). Head narrowed behind eyes, in lateral view temple 0.4–0.5 as long as compound eye, more buccate in males, 0.6–0.7 times as wide as compound eye. Lateral ocellus touching compound eye. In female lateral ocelli quite large, the distance between lateral ocelli about 0.4 times the diameter of ocellus. Malar space about 0.1 times as long as mandibular base in female and about 0.2–0.3 times in males. Mandibular gape right-angled, with internal angles. Wing membrane weakly yellowish. Ramellus distinct, reaching 0.2–0.3 the width of discosubmarginal cell. Radius evenly curved (as in Fig. 13A). Mesopleuron polished or sometimes weakly shagreened with quite weak punctures, interstices between punctures about equal or slightly larger than their diameter. Epicnemial carina, in antero-ventral view, with pleurosternal angles obviously anterior to sternal angles. Pleurosternal angles rounded, strongly obtuse. Scutellum with lateral carinae only indicated basally (as in Fig. 6A). Propodeum with very weak rugose structure, shiny with anterior and posterior transverse carina strongly raised in female (Figs 10B, 47 A–B). Anterior transverse carina in males often weak or absent laterally. Petiolar carinae usually strong. Longitudinal carinae delimiting area superomedia in large specimens rather strong, in smaller specimens frequently weak or absent, but normally clearly indicated at the junction with the posterior transverse carina. Propodeum centrally, between anterior and posterior transverse carina, usually with a distinct longitudinal fold in both males and females (Figs 10B, 47A). Hind trochantellus shorter than wide in dorsal view. Legs, especially in females, normally quite stout with hind femur about 6.0 times as long as wide. Hind tarsus stout, fourth segment about 2 times as long as wide; fifth segment slightly longer than fourth (Fig. 8H), mid tarsus with fourth segment stout 0.6 times as long as fifth segment. Sclerotised part of first sternite ending slightly posterior to spiracle (as in Fig. 6 G–H). Inner spur of hind tibia as long as 0.4 times hind metatarsus.
Colour
Body testaceous, frequently with distinct brownish patches on mesosternum, mesopleuron, propodeum and three stripes on mesoscutum. Mandibular teeth black. Inner and outer eye margins yellowish. First tergite often distinctly paler anterior to spiracle. Antennae bright orange. Ovipositor sheath often infuscate, slightly contrasting with posterior metasomal segments, in specimens with infuscate markings frequently brownish.
DNA barcode
The DNA barcode sequences of nine Swedish specimens of Ophion costatus are available at the BOLD systems database (www.boldsystems.org, BIN. BOLD: ADG0653. Specimen codes: STI-NJBC: 35, 38, 235–241).
Ecology
The species occurs primarily in forest landscapes and is active during August–October. The known hosts are Acronicta Ochsenheimer, 1816 species. Ophion costatus has been reared from Acronicta leporina (Linnaeus, 1758) and the original description refers to a rearing from A. aceris (Linnaeus, 1758), both of which have very hairy final instar larvae.
Distribution in Sweden
A common species in Southern and Central Sweden, rarer in the north.
Remarks
The type material of Ophion costatus is lost and the species has historically been the subject of numerous misinterpretations. This study shows that the name applies to one of the species in an aggregate previously treated under the name Ophion parvulus (see Discussion). Ophion costatus is distinguished from the other species in the aggregate currently known from Sweden on the stouter tarsal segments in the female, the usually typical carination of the propodeum and the generally larger size. The flagellomeres have approximately the same shape as in Ophion parvulus but usually have slightly longer pilosity. The barcoded specimens (Fig. 1) forms three separate groups that share the same distinguishing characters.
description: Published as part of Johansson, Niklas & Cederberg, Björn, 2019, Review of the Swedish species of Ophion (Hymenoptera: Ichneumonidae: Ophioninae), with the description of 18 new species and an illustrated key to Swedish species, pp. 1-136 in European Journal of Taxonomy 550 on pages 59-60, DOI: 10.5852/ejt.2019.550, http://zenodo.org/record/3476402