They need no males and no time at all

I was recently asked to identify greenhouse thrips.

These insects frequently appear as tiny specs on leaves in greenhouses.

The greenhouse thrips, Heliothrips haemorrhoidalis, are about 1.3mm-long and dark brown anteriorly with the posterior lighter.

The wings are pale, narrow and fringed with long hairs.

The legs and long, tapered antennae are pale yellowish white.

Females lay eggs which produce females — their reproduction is by parthenogenesis.

Using her saw-like ovipositor, the female cuts slits into leaves, into which she lays 10-25 eggs.

The eggs hatch about 10 days later.

Under high humidity and moderate temperature, the life cycle can take less then three weeks and thrip populations may grow quickly.

Thrips are readily controlled by products bought in garden shops.