FAMILY DINOPIDAE

The members of this remarkable family capture their food by casting a net over it - even moths in flight are sometimes captured.  The family contains two genera, dinopis and menneus, the former being the commoner of the two.  The genus dinopis  is comprised of nine species, the two commonest of which are featured here

Retiarius Spider - Dinopis bicornis
A nocturnal spider with a widespread distribution and common in Sydney suburbs.  This species builds a rectangular net after dark and destroys it before daylight, a new net being built each night.  The anterior median eyes are of enormous size and are directed forward, a feature lacking in the genus menneus.  During daylight hours, the spider hangs head downward among twigs or dead grass with its legs stretched out in pairs.  This makes it almost impossible to detect, even at close range.  The male builds nets until the moult which brings him to maturity, after which the urge to mate is so great that he neglects food and the means of capturing it.  After mating takes place the male dies which is not uncommon among spiders.

Some time after mating takes place, the female builds the egg sac, fastens one or another leaves around it, then leaves it.  The egg sac is suspended on strong threads about 3 cm long and has a hard waterproof covering.  This covering, though tough is not strong enough to prevent a minute wasp from drilling into it to lay her eggs.  The wasps are not parasitic and emerge from the sac just after the spiderlings have left it.  The purpose of this a+

ppears to be to save the mother wasp the trouble of building a nest for her eggs.  After leaving the egg sac, the spiderlings spin a few strands of fine web and live in a group for two to three weeks, then disperse by ballooning. 

description
Body length: male up to 15mm, female up to 20mm.   
Colour: as illustrated however variable depending upon habitat
Identification: by the enormous black anterior median eyes and abdomen
Egg Sac: spherical 9mm in diameter, light brown in colour with black dots sprinkled over the surface
Food: a wide variety of insects
Dimorphism: male much smaller and slimmer  then the female with longer legs
Web Snare a rectangular net of crinkly silk held by the claws of legs.
 

Dinopis bicornis (male) after final moult

Dinopis bicornis (female)
 

Retiarius Spider - Dinopis subrufa
Though of a different colour to D. bicornis, this species has the same habits and is often found in the same locality.  It is found right across the continent and in Tasmania. 

description
Body length: male up to 14mm, female up to 23mm.   
Colour: yellow brown to grey on the dorsal surface with an orange to red patch down the centre
Identification: by the huge anterior median eyes and colour on the ventral surface of abdomen
Egg Sac: similar to, but slightly larger and lighter in colour than D. bocornis
Food: a wide variety of insects
Dimorphism: male much smaller and slimmer  then the female with longer legs
Web Snare a rectangular net of crinkly silk held by the claws of legs.
 

Dinopis bicornis (male) after final moult

Dinopis bicornis (female) with net
 

Retiarius Spider - Menneus unifasciata
This species ranges for New South Wales to North Queensland and though it belongs to the same family as the dinopids, its habits vary somewhat.  The principle variations of habiit are: the net is held and cast in a different manner and the egg-sac is not suspended on threads but placed in the leaf litter on the ground.  Dinopids usually build their net about 30-40cm from the groung whereas the genus build theirs two to three times higher in very tall ferns or in the lower twiggy brances of trees.  Dinopids hold their nets by the four cornets, menneus hold theirs by the two back corners, and in the centre and on the edge.  The front corners are fastened to a thread of silk.  Dinopids hold their net flat, menneus fold it to the centre to form a "V". 

Dinopids are usually found in fairly dry, open country, menneus are found in damp, semi rain forest.

description
Body length: male up to 7mm, female up to 9mm.   
Colour: dusty brown, a lighter median stripe running the full length of the body on the dorsal surface
Identification: by dorsal stripe, huge anterior median eyes are lacking
Egg Sac: spherical, 4mm in diameter, brown in colour, outer case of hard papery silk, no black dots
Food: small flying insects
Dimorphism: male of lighter build and slightly small than the female
Web Snare a rectangular net which is thrown over the prey
 

Menneus unifasciata (male)

Menneus unifasciata (female)
 

Retiarius Spider - Menneus despiciens
This species is slightly larger than M. unifasciata though of similar habits.  Where the former are sometimes found on the edge of semi-rain forest, this species seems to be confined to darker and thicker regions of the forest.

description
Body length: male up to 8mm, female up to 10mm.   
Colour: variable depending up the habitat
Identification: large anterior median eyes are lacking, distinct flange in centre of abdomen
Egg Sac: spherical, 4.5mm in diameter, deep rich brown in colour
Food: small flying insects
Dimorphism: male slightly small than the female
Web Snare a rectangular net which is held with the claws of legs one and two
 

Menneus despiciens (female)