Diamond Comb-Footed Spider Identification in Australia

About the Diamond comb-footed spider

The diamond comb-footed spider, Cryptachaea veruculata, is a tiny Australian member of the cobweb-spider family Theridiidae. A mature female is only about 4 mm long and typically has a rounded, patterned abdomen above a small irregular web on green vegetation or a sheltered built structure; a pink to mauve egg sac can be a useful supporting clue. It is easily confused with other small comb-footed spiders, and colour or a “diamond” mark is not enough for species certainty. The strongest field identification combines body size, several clear views, web, egg sac and locality; atypical spiders may need an arachnologist and adult genital anatomy.

How to identify Cryptachaea veruculata cautiously

Start with scale and shape. Australian field accounts place the female at about 4 mm body length and the male below about 2 mm; measure the body only, because thin legs exaggerate size. The female has the theridiid combination of a small cephalothorax, slender legs and a rounded to slightly high abdomen. Its variable dorsal pattern commonly combines a dark median area with pale cream, white or brown patches that can read as a diamond from some angles. That common name is a prompt, not a diagnostic character. A true comb-footed spider has a row of serrated bristles on the last segment of the fourth leg for throwing sticky silk, but this “comb” is usually beyond an ordinary phone photograph. Smith and colleagues’ peer-reviewed revision confirms the accepted Cryptachaea placement and illustrates adult anatomy. Species-level confirmation of an unusual specimen depends on mature genital characters, not pattern matching alone.

Clues that are not enough on their own

• A diamond, skull or face-like mark seen from one angle
• Any tiny round-abdomen spider in a messy web
• Pink or mauve silk without a clear view of the adult spider
• A state filter or crowd-sourced map point treated as proof of identity
• Small size treated as proof that a bite cannot matter

Colour, sex and life-stage variation

Females are larger and more round-bodied than males, especially when carrying eggs. A mature male is much smaller, slimmer and leggier, with enlarged pedipalps near the mouth; it may not show the female’s neatest diamond-like pattern. Juveniles can be paler, less strongly marked and impossible to separate confidently from other tiny theridiids in a photograph. Individual females vary in how much dark, cream, brown or whitish pigment they carry, while a full abdomen, moult, lighting and viewing angle change the outline. The egg sac also changes appearance as silk ages or becomes dusty. Published measurements differ among regions and references, another reason to treat “about 4 mm” as context rather than a ruler test. Do not force a small male, spiderling or strongly atypical female to this species merely because it shares a messy web.

Behaviour, web and retreat

This is a sit-and-wait web hunter. It builds a small, untidy three-dimensional tangle rather than an orb, funnel or flat sheet. Tensioned sticky lines intercept tiny insects and other arthropods; the spider reads vibrations, approaches across supporting threads and uses its hind-leg comb to throw or draw sticky silk around prey. It often rests within the web or close to a protected edge rather than roaming in the open. On vegetation, leaves and stems anchor the web; around buildings, windowsills, ledges and corners provide equivalent shelter. Females suspend and guard pinkish to mauve silk egg sacs near their normal position. Web shape, retreat and egg sac strengthen an identification, but other Theridiidae use broadly similar tangled webs. A web being absent after disturbance also does not disprove the species.

Australian distribution

Australian Faunal Directory accepts Cryptachaea veruculata (Urquhart, 1886), and the Atlas of Living Australia links its accepted concept to AFD. An exact Atlas taxon query at review time returned 2,076 occurrence records: 825 Victoria, 434 New South Wales, 211 Queensland, 188 Australian Capital Territory, 166 Western Australia, 150 South Australia, 94 Tasmania, one record labelled Wellington and seven without a supplied state. The isolated overseas/province value and uneven totals show why occurrence data need checking; they are neither population estimates nor a guarantee that every identification is correct. Current taxonomic sources also record the species from New Zealand and Australian offshore islands, with introductions in parts of Europe. This page uses the Australian records for field context and does not infer abundance from upload density.

What to do if you find one

Leave an occupied garden web in place when practical: the spider is a tiny predator and normally remains with its silk. Before pruning or wiping a ledge, inspect for a female and egg sacs. For identification, take an uncropped dorsal image, a side view, a scale photograph and a wider picture of the complete web; photograph rather than opening an egg sac. If a web must be moved, wear gloves, hold a container below it and use a long soft brush or the supporting leaf to guide the spider and egg sac together into the container. Release them into sheltered vegetation nearby, away from children’s play areas and door handles. Do not pick up the spider with fingers. Submit a clear unusual or out-of-range record to a museum or Atlas with date and locality, and retain “small comb-footed spider” when the evidence cannot support an exact species.

Compare with similar spiders

Use body shape, web or retreat, location and behaviour together before settling on a likely match.

• Brown widow spider — White porch spider - Cryptachaea gigantipes is a close relative with an unusually long first pair of legs and a generally pale body; each long first-leg segment can approach or exceed body length. Adult anatomy is the safe boundary when proportions are unclear.
• Redback spider — Redback spider - adult female Latrodectus hasselti is larger and glossy black with a red dorsal stripe and ventral hourglass, although juveniles and males are patterned. Never use a pale back pattern alone to dismiss a possible redback.
• Brown house spider / cupboard spider — Brown house or cupboard spider - Steatoda grossa is generally larger, darker and less intricately patchy, with a stronger bulbous abdomen. Its messy house web overlaps, so use scale, several body views and expert help.
• Common house spider — Common house spider - Parasteatoda tepidariorum is usually larger and variably mottled and can occupy the same built structures. Pattern overlap is substantial; mature reproductive anatomy may be required for a defensible species identification.

Sources for this profile

These accessible authoritative sources support the identification and bite-safety context on this page.

• Australian Faunal Directory: Cryptachaea veruculata
• Atlas of Living Australia: Cryptachaea veruculata
• Zootaxa: Cryptachaea revision and comparison
• Australian Museum: White porch spider comparison
• NSW Environment: Spiders in Sydney
• healthdirect: Spider bites

Profile review

Published by Spider Identifier Australia. Last factual review: 11 August 2026.