Ichneumon xanthorius♀︎♂︎

Last update: 23 November 2024

Species Ichneumon xanthorius
Genus ICHNEUMON
Family ICHNEUMONIDAE (Ichneumon wasps)

Ecological role Idiobiont ectoparasitoid + pollinator

Activity
janfebmaraprmayjunjulaugsepoctnovdec

Observations
2021-V-232020-V-302020-IV-202020-IV-122020-IV-082019-VI-232019-VI-212019-VI-16
Months
JanFebMarAprMayJunJulAugSepOctNovDec
Years
201920202021

1. DISTRIBUTION

Ichneumon xanthorius^{[Soortenregister],[Broad 2011],[Perkins 1959],[Perkins 1960]}is an uncommon wasp that occurs throughout the Netherlands ^{[Broad 2011]}.

In some litereature the species is referenced with its old name Amblyteles equitatorius.

2. BEHAVIOUR

2.1. ACTIVITY

The species is active from April to August with a peak for males in June and July, and for the females in April and May ^{[Broad 2011]}.

2.2. DEVELOPMENT

The species overwinters as larva and has possibly more generations per year ^{[Hinz & Horstmann 2007]}. The larvae pupate in the ground in May ^{[Hinz & Horstmann 2007]}.

Development take on average 30 days for females and 26 days for males ^{[Hinz & Horstmann 2007]}.

3. PARASITIC RELATIONS

I. xanthorius is a polyphagous ^{[Hinz & Horstmann 2007]} endoparasitoïd on moths from the Noctuidae family ^{[Hinz & Horstmann 2007]}, especially on cocoons in the ground, on the following species occurring in the Netherlands ^{[Vlinderstichting.nl]}:

Owlet moths
(NOCTUIDAE)

–Noctua comes ^{[Hinz & Horstmann 2007]}
–Noctua fimbriata ^{[Hinz & Horstmann 2007]}
–Xestia baja ^{[Hinz & Horstmann 2007]}
–Xestia ditrapezium ^{[Hinz & Horstmann 2007]}
–Xestia stigmatica (syn. X. rhomboidae) ^{[Hinz & Horstmann 2007]}
–Xestia trianglum ^{[Hinz & Horstmann 2007]}

The following hosts have been observed in the garden:

Owlet moths
(NOCTUIDAE)

– Lesser yellow underwing (Noctua comes) ^{[Hinz & Horstmann 2007]}

4. IDENTIFICATION

It is a large wasp with a length of 15mm
(different internet sites provide a length of 15mm for males and females. The length of the female is specified as 13 – 14 mm in the Perkins key ^{[Perkins 1960]}).

The characteristics of I. xanthorius are ^{[Perkins 1960]}:

Females

1. Mandible with one tooth
2. Thyridia short as very narrow transverse band
3. Gastrocoelus quite large, width at least as wide as distance between gastrocoeli

4. Terga 5, 6 and 7 with yellow marks
5. Terga 1 to 4 with wide yellow band apically