Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

ICHNEUMONIDAE: : Phytodietus Gravenhorst 1829


Diagnosis:

Phytodietus is relatively simple to identify. There are very few taxa it can be confused with. However, it is not commonly encountered. It has a relatively distinct body colouration, with very yellow hind femora and black hind tibia.

Characteristics of Phytodietus include: 1. Body size just slightly <10mm; 2. Position of spiracle on Tergite 1 is at the centre; 3. Shape of aerolet in forewing is petiolate; 4. Colour of face is not all black; 5. Metasoma is compressed laterally; 6. Ocelli are small; 7. Length of antennae are as long as the body; 8. Length of ovipositor is distinct but not longer than body; 9. Wings are present; 10. Colour of wings are hyaline (clear); 11. Sternaulus (on mesopleuron) is absent; 12. Shape of face in lateral view is flat or only weakly bulging; 13. Sternite on T1 (viewed laterally) is not extending past spiracle; 14. Shape of T1 (viewed laterally) is evenly curved; 15. Number of teeth in mandibles is 2; 16. Patterns on metasoma is the same colour throughout (black, dark brown); 17. T1 longer than T2; 18. Sculpture on mesoscutum is smooth, very polished; 19. Width of T1 (viewed dorsally) is generally of uniform width (slightly widening posteriorly); 20. Glymma on T1 is present as a deep pit that produces a small hole in T1; 21. Sculpture on metasoma is smooth with a glossy appearance (highly polished, no punctures); 22. Propodeum reaching just past the coxal insertion, but not reaching halfway along metacoxae.

Similarity to Other Taxa

Phytodietus is a mid-sized Ichneumonid in New Zealand. They are siimilar in size to: Dusona , Liotryphron , Habronyx , Lissonota and Venturia . It can be separated from other similar sized taxa by having a deep glymma on T1, the ovipositor length distinct but not longer than the body, a petiolate areolet in the forewing.

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Distribution in NZ


North Island: AK, BP, CL, GB, HB, TO, WN, RI. South Island: NN, BR, MC, DN, CO, WD, FD, SI, SL.

Species in NZ

One endemic species Phytodietus zealandicus (Ashmead 1900).

Biology & hosts

Phytodietus is a large cosmopolitan genus around the world, but the New Zealand species is placed in its own subgenus, Euctenopus . Little is known about the biology or host of Phytodietus zealandicus , however, it is nocturnal. It is widespread in New Zealand and has also been collected from a wide range of habitats, such as urban areas, beech forest, swamps, and coastal lagoons/beaches.

Sources of information

Gauld ID 1984. An Introduction to the Ichneumonidae of Australia. London, British Museum (Natural History). 413 p.
Parrott AW. 1951. New Zealand Ichneumonidae. I. The genus Netelia Gray. ( Paniscus of authors) (Tryphoninae: Phytodietini). Transactions of the Royal Society of New Zealand (Zoology) 79: 286-293.

Citation

Ward DF & Schnitzler FR. 2013. Ichneumonidae of New Zealand. Genus Phytodietus http://ichneumonidae.landcareresearch.co.nz
Accessed: 14 October 2019

Revised

v1.0. Ward DF & Schnitzler FR. 2013