The Spiny Ridge-backed Stick Insect

Spinotectarchus acornutus · Order: Phasmida · Family: Phasmatidae

No source yet on danger. We have no source yet on whether it bites, stings or damages anything.
The Spiny Ridge-backed Stick Insect
Photo: Shaun Lee, CC BY

Females grow to about 4.8 cm while males are around 3.5 to 3.7 cm long. They come in brown to green colour forms, with females having a more ridged back. They live in native bush and regenerated forest in Northland, often on climbing rātā, fragrant fern, certain epiphytes and kohekohe trees.

Source: Wikipedia

How to recognize it

Both sexes show a range of colours from brown to green, and females have a more ridged dorsal side.

Source: Wikipedia

Size

Female bodies can reach up to 4.8 cm, while males are between 3.5 and 3.7 cm long.

Source: Wikipedia

Where it lives

They inhabit native bush and regenerated forest in Northland. Common host plants include climbing rātā, fragrant fern, the epiphyte Collospermum hastatum, and kohekohe.

Source: Wikipedia

Where it comes from

The species is limited to the northern part of New Zealand's North Island and some offshore islands. The type specimen was collected on Great Barrier Island.

Source: Wikipedia

Lookalikes

It can be distinguished from similar stick insects by genital morphology, and it is not closely related to other New Zealand stick insect genera.

Source: Wikipedia

More photos

The Spiny Ridge-backed Stick Insect photo 3
Photo: unknown, CC0

Questions people ask

How big do Spinotectarchus acornutus insects get?

Females can grow up to about 4.8 cm, while males are typically 3.5 to 3.7 cm long.

Source: Wikipedia

What colours do they have?

They range from brown to green, and females have a more ridged back.

Source: Wikipedia

Where are they found in New Zealand?

They live in native bush and regenerated forest in Northland, especially on climbing rātā, fragrant fern, certain epiphytes and kohekohe trees.

Source: Wikipedia

Same family (Phasmatidae)

Smooth Stick InsectSmooth Stick InsectClitarchus hookeriMargin-winged Stick InsectMargin-winged Stick InsectCtenomorpha marginipennisDamages trees, gardens or cropsPrickly Stick InsectPrickly Stick InsectAcanthoxyla prasinaDamages trees, gardens or cropsSpur Legged PhasmidSpur Legged PhasmidDidymuria violescensSpiny Leaf insectSpiny Leaf insectExtatosoma tiaratumCan irritate skinTitan Stick InsectTitan Stick InsectAcrophylla titan

Sources

  • Wikipedia: https://en.wikipedia.org/wiki/Spinotectarchus

Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia

Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-23.

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