Sigmothrips aotearoana Ward, 1970
The endemic Hangehange thrips, Sigmothrips aotearoana Ward, 1970 is one of four species of the subfamily Panchaetothripinae in New Zealand. The other three species are the adventive species, Greenhouse thrips, Heliothrips haemorrhoidalis (Bouche, 1833), Banana silvering thrips, Hercinothrips bicinctus (Bagnal, 1919) and Palm thrips, Parthenothrips dracaenae (Heeger, 1854). This subfamily is distinguished from other Thripidae by the dorsal surface of the head and prothorax being covered in reticulate sculpture. The maxillary palp is two segmented and the forewing has the first vein more or less fused to the costa. Another distinguishing feature of the four species in New Zealand is that they feed on mature or almost mature plant leaves.
Biostatus and distribution
This endemic species of thrips is widespread in native habitats in New Zealand. It has only been found feeding on native plants.
Conservation status: Widespread in the New Zealand on native plants in native habitats, not threatened.
Life stages and annual cycle
Hangehange thrips may breed all year in Auckland, but are mostly seen in the spring and summer. They live mainly on the mature or almost mature leaves of their host plants as do the other three species of the subfamily Panchaetothripinae found in New Zealand.
Adults like the other active stages of Hangehange thrips are relatively long and thin. The body is brown and its surface is strongly sculptured and reticulate. The head has two brown antennae, two compound eyes and on the underside the mouth cone contains a pair of short maxillary stylets and a single stout mandible. The head has distinctive side projections. There are three pairs of brown legs and two pairs of wings that when not used for flying are held over the abdomen. The relatively narrow forewings have a white band near their base and three darker areas. The tip of the abdomen contains the genitalia. The female also has an ovipositor for inserting eggs into leaves. Males are rarely collected.
Eggs and larvae
Eggs are laid in either the upper or underside of the leaf depending on the plants species. A thin larva hatches from the egg. It is the shape of a tiny white wingless adult. Like the adult it has three pairs of legs, a pair of antennae and the same structures for feeding. There are two larval stages. Juvenile thrips, including prepupae and pupae go to the next stage by moulting. This involves the dorsal skin splitting and the next stage pulling itself out of the old skin. The second larva looks like the first larva and may be come yellow-green coloured. The last segment of the abdomen is brown and tubular and has long setae (hairs) around the tip of the anus. These hairs help hold the faecal droplet. At intervals the faecal droplet is probably flicked away. Sometimes the droplet runs over the body.
Prepupa and Pupa
When the larva is fully grown it drops to the ground and hides in the litter or soil. Here it moults into the prepupa, the first of two non-feeding stages. The prepupa looks like a large larva with short wing buds. The tip of the abdomen has three pairs of spine-like setae, two pairs on segment 9 and one pair on segment 10. The prepupa moults into the pupa. The pupa has longer wing buds and the antennae are folded back over the head. It also has the six spines at the tip of the abdomen. It is assumed that the spines on the tip of the abdomen are used for defence. Both the prepupa and pupa can walk around.
Feeding and plant damage
Hangehange thrips feed on mature or almost mature leaves rather than young rapidly expanding leaves. Larvae and adults use the stylets in their mouth cone to feed. They puncture plant cells with their single mandible and suck up the plant cell contents with their maxillary stylets. Their feeding kills the surface cells of the leaves creating distinctive pale areas of dead cells. The larvae carry a dark faecal droplet at the tip of the abdomen, that may run over the body or be flicked away at intervals.
Hangehange thrips are found on mature or almost mature leaves of host plants with typical thrips feeding damage. With the aid of a strong magnifying glass, they can be distinguished from the other three species in the subfamily Panchaetothripinae. The dorsal surface the head and prothorax of adults of the New Zealand species in this subfamily is strongly sculptured and reticulate.
Adult Hangehange thrips, Sigmothrips aotearoana body is dark brown and it has narrow wings with dark and pale areas. The wings are similar to those of the banana silvering thrips, Hercinothrips bicintus, but different from Palm thrips, Parthenothrips dracaenae, which has broad wings. Adult Hangehange thrips and banana silvering thrips are best distinguished by the shape of the head. The lateral margins of the head of the Hangehange thrips have prominent angular projections whereas the lateral margins of the banana silvering thrips head appear smooth. The Greenhouse thrips, Heliothrips haemorrhoidalis, has white bases to its wings and white legs, whereas the Hangehange thrips has brown legs.
Colonies of Hangehange thrips can easily distinguished from colonies of two species of Panchaetothripinae. Only adults and larvae are present on leaves in colonies of Hangehange thrips and banana silvering thrips, whereas colonies of Greenhouse thrips, Heliothrips haemorrhoidalis, and Palm thrips may have prepupae and pupae present as well as adults and larvae.
If adults are absent, colonies of Hangehange thrips and banana silvering thrips can be distinguished if you have access to a binocular microscope. Look at the tip of the abdomen of the larvae. The Hangehange thrips larvae have long setae, but the banana silvering thrips larvae have no setae around the opening. This is the reason larvae are more likely to be covered by dark faecal matter. If the last two abdominal segments are visible, the terminal segment of the Hangehange thrips is almost as wide at the tip as it is at the base, whereas the segment in the banana silvering thrips is almost conical.
No natural enemies have been recorded for this endemic thrips. It is probably eaten by spiders and insect predators. There may also be an egg parasitoid.
The Hangehange thrips prepupae and pupae live in the litter or soil. They both have six spine-like seate at the tip of their abdomen. It is assumed that these spines are used for defence.
Hangehange thrips only feeds on native plants. They feed on mature or almost mature leaves of trees, shrubs and herbs. The adults and larvae often feed on the upper side of leaves.
Feeding and plant damage
Hangehange thrips feed on mature or almost mature leaves rather than young rapidly expanding leaves. Larvae and adults use the stylets in their mouth cone to feed. They puncture plant cells with their single mandible and suck up the plant cell contents with their maxillary stylets. Their feeding kills the surface cells of the leaves creating distinctive pale areas of dead cells. The larvae carry a dark faecal droplet at the tip of the abdomen, which is probably flicked away at intervals. There are usually dried black faecal droplets on leaves where the thrips have been feeding.
|Common Name(s)||Scientific Name||Family||Reliability Index||Biostatus|
|New Zealand bitter cress, Panapana||Cardamine debilis Banks ex DC.||Cruciferae||10||endemic|
|Centella, Gotu cola||Centella uniflora (Colenso) Nannf.||Umbelliferae||9||indigenous, non-endemic|
|Kākawariki, Kanono, Kapukiore, Karamū-kueo, Kueo (fruit), Manono, Pāpāuma, Raurēkau, Toherāoa||Coprosma grandifolia Hook.f.||Rubiaceae||10||endemic|
|Large seeded coprosma, Kākaramū, Kākarangū, Karamū, Kāramuramu, Karangū||Coprosma macrocarpa Cheeseman||Rubiaceae||10||endemic|
|Glossy karamu, Kākaramū, Kākarangū, Karamū, Kāramuramu, Karangū||Coprosma robusta Raoul||Rubiaceae||10||endemic|
|Round-leaved coprosma||Coprosma rotundifolia A.Cunn.||Rubiaceae||8||endemic|
|Dwarf cabbage tree, Short-stemmed cabbage tree, Ti rauriki, Kōpuapua, Korokio, Mauku, Tī awe, Tī kapu, Tī koraha, Tī kupenga, Tī papa, Tī rauriki||Cordyline pumilio Hook.f.||Asparagaceae||10||endemic|
|Spider orchid||Corybas sp. (Hook.f.) Rchb.f.||Orchidaceae||7||unknown|
|Corybas trilobum (Hook.f.) Rchb.f.||Orchidaceae||10||endemic|
|Tree fuchsia, Hōnā (fruit), Kōhutuhutu, Kōnini (fruit), Kōtukutuku, Māti (fruit), Tākawa (fruit)||Fuchsia excorticata (J.R.Forst. & G.Forst.) L.f.||Onagraceae||10||endemic|
|New Zealand privet, Hangehange, Hengahenga, Pāhengahenga, Pāpā, Pāpāhenga, Pāpāuma, Whangewhange||Geniostoma ligustrifolium A.Cunn. var. ligustrifolium||Loganiaceae||10||endemic|
|Shrubby haloragis, Toatoa||Haloragis erecta (Banks ex Murray) Oken||Haloragaceae||9||endemic|
|Pigeonwood, Kaiwhir, Kaiwhiria, Kōporokaiwhiri, Pōporokaiwhiri, Pōporokaiwhiria, Porokaiwhiri, Porokaiwhiria, Poroporokaiwhiria||Hedycarya arborea J.R.Forst. & G.Forst.||Monimiaceae||10||endemic|
|Hydrocotyle elongata A.Cunn.||Araliaceae||10||endemic|
|New Zealand lobelia, Shore lobelia, Punakuru, Pūrao, Waewae-koukou||Lobelia anceps L.f.||Campanulaceae||10||indigenous, non-endemic|
|Panakeake, Pānakenake||Lobelia angulata G.Forst.||Campanulaceae||5||endemic|
|Narrow-leaved mahoe, Willow-leaved mahoe, Kaiwētā, Māhoe-wao, Tāranga||Melicytus lanceolatus Hook.f.||Violaceae||10||endemic|
|Whiteywood, Hinahina, Inaina, Inihina, Māhoe, Moeahu, Kaiweta||Melicytus ramiflorus J.R.Forst. & G.Forst.||Violaceae||10||indigenous, non-endemic|
|Tutukiwi||Pterostylis banksii A.Cunn.||Orchidaceae||10||endemic|
|Seven-finger, Kohi, Kotētē, Patate, Patatē, Patē, Patētē||Schefflera digitata J.R.Forst. & G.Forst.||Araliaceae||10||endemic|
|New Zealand chickweed||Stellaria parviflora Banks et Sol. ex Hook. f.||Caryophyllaceae||8||indigenous, non-endemic|
Reproduction and Parthenogenesis in Thysanoptera
In Thysanoptera, females are diploid (2 sets of chromosomes) and males are haploid (one set of chromosomes). Males are produced from unfertilised eggs. This type of reproduction is called Arrhenotoky. The proportion of males to females in a population is variable. In Palm thrips this appears to be related to temperature. In a warm greenhouse (25-28°C) there are very few males, 6-7 per 100 females, while in a cooler greenhouse (18-20°C) there are more males. Where there are very few or no males, females can reproduce without fertilisation. This is called Thelotoky, form of parthenogenesis. In populations where there are very few males there are probably two types of female present, Arrhenotokous and Thelotokous.
Palm thrips is the first species from the Thysanoptera order that was found to be capable of thelytokous parthenogenetic reproduction. This characteristic is contained in the Latin name of the genus, Parthenothrips.
Lewis T. 1973. Thrips their biology, ecology and economic importance. Academic Press, London, UK. Pp. 1-349.
Martin NA. 2016. Distinguishing feature of immature stages of Panchaetothripinae (Thysanoptera: Thripidae) known in New Zealand. New Zealand Journal of Zoology 43 (4): 1-8.
Martin NA. 2017. Host plants of Panchaetothripinae (Thysanoptera: Terebrantia: Thripidae) in New Zealand. New Zealand Journal of Zoology 44 (1): 1-8.
Martin NA, Mound LA. 2004. Host plants for some New Zealand thrips (Thysanoptera: Terebrantia). New Zealand Entomologist. 27: 119-123.
Mound LA, Walker AK. 1982. Terebrantia (Insecta: Thysanoptera). Fauna of New Zealand. 1: 1-113.
Plant-SyNZ: Invertebrate herbivore-host plant association database. plant-synz.landcareresearch.co.nz/
The New Zealand Institute for Plant & Food Research Limited (Plant & Food Research) for permission to use photographs.
Landcare Research New Zealand Limited (Landcare Research) for permission to use photographs.