Copy a link to this page Cite this record

Delphacid parasitoid wasp - Gonatopus alpinus

By N A Martin (2019)

Show more

Click to collapse Classification Info






Gonatopus alpinus (Gourlay, 1954)

Click to collapse Common names Info

Delphacid parasitoid wasp

Click to collapse Synonyms Info

NeoGonatopus alpinus Gourlay, 1954

Click to collapse Biostatus and distribution Info

This endemic wasp was first found in the 1950’s in the southern alps. It has now been found on the East and West coasts of Auckland. It is a parasitoid of planthoppers in the family Delphacidae (Hemiptera) that live on low growing plants. The wasp adults may be winged or wingless, the latter looking similar to ants.

Conservation status: The wasp parasitoid is probably widespread and is not endangered.

Click to collapse Life stages and annual cycle Info

The only known hosts of the wasp are nymphs and brachypterous (short-winged) adults of plant hoppers in the family Delphacidae. The known hosts live on plants close to the ground in coastal and alpine habitats. The adults may be winged or wingless and are probably the overwintering stage. Wasp larvae have been found on hosts in spring and summer.

The head and body of the adult wasp is about 3 mm long and dark brown. The abdomen of the wingless adults has dark hind edges to each abdominal segment. The adults have three pairs of legs and pair of antennae. Winged adults have two pairs of wings. The wingless adult has a narrow thorax, middle section of the body, and legs with swollen segments. Wingless adults may be confused with worker ants.

Eggs are probably laid on large nymphs and short-winged adults. The ectoparasitoid larva pushes its head between body segments, usually between the end of the thorax and the first abdominal segment. The rest of the body extends out between the planthoppers body segments. The larva’s body has two round plates, one above and the other on its underside. As it grows the plates are pushed apart. When the larva is fully grown, it kills the planthopper the then crawls away from its old skin and in a sheltered place it spins a white cocoon in which it pupates. When the adult has developed it emerges from the pupa in the cocoon. When its body has hardened and its wings dried it chews a hole in the cocoon through which it emerges.

Click to collapse Natural enemies Info

No pathogens, parasitoids or predators of the Delphacid parasitoid wasp, Gonatopus alpinus, (Hymenoptera: Dryinidae) are known. The adults are probably caught by predatory insects, spiders and birds.

Click to collapse Prey/hosts Info

The Delphacid parasitoid wasp has been reared from or associated with four species of plant hoppers in the family Delphacidae (Hemiptera). The female lays an egg on a large nymph or a short-winged, brachypterous, adult. The larva attaches itself between body segments on the upper side. As it grows the body expands and becomes more obvious. Only one larva per plant hopper has been found.

This parasitoid may have more than the four known hosts.

Table: New Zealand hosts of Delphacid parasitoid wasp, Gonatopus alpinus, (Gourlay, 1954) (Hymenoptera: Dryinidae), from the Plant-SyNZ database (22 April 2019). The reliability score shows the quality of evidence for the host association (0-10, 10=high quality).
Scientific NameCommon NameClassification Reliability Index Biostatus
Delphacidae sp. (Apium) (Hemiptera: Delphacidae)5unknown
Delphacidae sp. (Tetragonia)Kiwi spinach planthopper(Hemiptera: Delphacidae)7endemic
Nilaparvata myersi Muir, 1923 (Hemiptera: Delphacidae)10endemic
Sulix tasmanii (Muir, 1923) (Hemiptera: Delphacidae)10endemic

Click to collapse Information sources Info

Gourlay,E.S. 1954: The Dryinidae, a family of Hymenoptera new to New Zealand. N.Z. ENTOMOL.: 1(4):3-5.

Olmi M. 2007. New Zealand Dryinidae and Embolemidae (Hymenoptera: Chryidoidea): new records and description of Bocchus thorpei new species. Records of the Auckland Institute and Museum. 44: 5-16.

Click to collapse Acknowledgements Info

The New Zealand Institute for Plant & Food Research Limited (Plant & Food Research) for permission to use photographs.

Click to collapse Other images Info

Click to go back to the top of the page