ICHNEUMONIDAE: : Xanthocryptus Cameron 1901

Diagnosis:

Males and females of Xanthocryptus have some different characters.

Characteristics of Xanthocryptus include: 1. Body size:<10mm [male], but 10-20mm [female]; 2. Position of spiracle on T1 is at, close to, or before centre; 3. Shape of aerolet in forewing is very small pentagonal (closed); 4. Colour of face is not all black; 5. Metasoma compressed is dorsal-ventrally; 6. Size of ocelli are small; 7. Length of antennae is shorter than body; 8. Length of ovipositor is very distinct but not longer than body; 9. Wings present; 10. Colour of wings hyaline (clear), or very lightly darkened; 11. Sternaulus (on mesopleuron) varies from short (less than 0.5x length mesopleuron) to long (more than 0.5x length mesopleuron); 12. Shape of face in lateral view is flat or only weakly bulging; 13. Sternite on T1(viewed laterally) does not extend past spiracle in the female, but it does extend past spiracle for the male; 14. Shape of T1 (viewed laterally) is evenly curved; 15. Number of teeth in mandibles 2; 16. Patterns on metasoma with very distinct black and white stripes; 17. Length of T1 vs T2 subequal in length; 18. Sculpture on mesoscutum is somewhat polished but also finely pitted, many hairs; 19. Width of T1 (viewed dorsally) of uniform width [male] but T1 gradually widening from anterior to posterior [female]; 20. Glymma on T1 absent; 21. Sculpture on metasoma smooth with a semi-glossy or satin appearance at least on T2; 22. Propodeum reaching past coxal insertion, but not reaching halfway along metacoxae.

Similarity to Other Taxa

Based on similar body colouration, Xanthocryptu s is most likely to be confused with Glabridorsum. In Xanthocryptus the spiracle on T1 is at, close to, or before centre; areolet in the forewing is small, and the white bands around the eyes are broken (they are continuous in Glabridorsum ). See Green (1984. A diagnostic aid. The Weta 7 : 65-67) for further help.

Xanthocryptus is a large-sized Ichneumonid in New Zealand. It is similar in size to: Rhyssa , Lissopimpla , Echthromorpha , Ophion (1 species), Enicospilus , Eutanyacra , Ichneumon , Netelia , Ctenochares , and Degithina . It can be readily separated from other similar sized taxa by having very distinct black and white stripes on the metasoma.

Compare

Distribution in NZ

North Island: ND, AK, BP, CL, HB, TO, WA, WI. South Island: NN, SD, BR, MB, MC, CO, WD. Offshore Islands: TH.

Species in NZ

One native species: Xanthocryptus novozealandicus (Dalla Torre 1902), which is also found in Australia and Papua New Guinea.

Biology & hosts

Xanthocryptus is a large genus restricted to Australia, Melanesia and New Zealand (Gauld 1984). The species in New Zealand, Xanthocryptus novozealandicus , is widespread and common.

It has been recorded from several species of longhorn beetles (Cerambycidae): Brounopsis hudsoni , Brounopsis sp., Didymocantha sp., Eburilla sericea , Hexatricha pulverulenta , Liogramma zealandica , Navomorpha sulcata , Oemona hirta , and Xylotoles griseus (Valentine & Walker 1991).

Sources of information

Gauld ID 1984. An Introduction to the Ichneumonidae of Australia. London, British Museum (Natural History). 413 p.
Green OR. 1984. A diagnostic aid. The Weta 7 : 65-67.
Harris AC. 1978. Mimicry by a longhorn beetle, Neocalliprason elegans (Coleoptera: Cerambycidae), of its larval parasitoid, Xanthocryptus novazealandicus (Hymenoptera: Ichneumonidae). New Zealand Entomologist 6 : 406-408.
Parrott AW 1953. The identity of two common species of ichneumon-wasps. New Zealand Entomologist 1 : 15-16.
Valentine EW & Walker AK. 1991. Annotated Catalogue of New Zealand Hymenoptera. DSIR Plant Protection Report 4. General Printing Services, 84 p.

Citation

Ward DF & Schnitzler FR. 2013. Ichneumonidae of New Zealand. Genus Xanthocryptus http://ichneumonidae.landcareresearch.co.nz
Accessed: 2 May 2024

Revised

v1.0. Ward DF & Schnitzler FR. 2013