Linyphiidae: sheet weavers and money spiders

Linyphidae is the largest spider family in the UK, with 270 species. Most of these are tiny, dark and and only identifiable with a microscope, the 'money spiders'. They typically build hammock-like webs held by a pattern of criss-crossing threads above and below. Liniphids usually hang upside down from their sheet web and do not use a retreat.
One of the largest species is the common Linyphia triangularis (above) whose webs hang in numbers from bushes in gardens and become very evident when covered in dew.

Neriene montana, is another large species (4-7 mm) common in gardens.

Stemonyphantes lineatus.

Gosammer and ballooning
These spiders can be incredibly numerous and active, and their drag silk threads can give fields a silvery shine, which is called gosammer. Money spiders disperse by ballooning. They climb up bushes and release a long silk line, which can get caught in the wind. Standing on tiptoes, the spiders are pulled up and lifted into the air.

Gossamer

A close-up of a gossamer-covered grass seed-head with money spiders ready to balloon.

Mating tactics
Linyphia has some interesting mating tactics I have blogged about before. Males have large chelicerae they use to fight other males while they guard a female.

Linyphia triangularis pair, the male is on the foreground. Males often sit on the female's web, mate guarding.

Money spider heads
Some money spiders have very unusual heads, with some of their eyes on top of turrets or humps (see if you can make sense of Walckenaeria!). These harbour glands that produce secretions, possibly nuptial gifts, during mating. Females of some species are known to hold the male's head during mating.

Egg sacs

Egg sacs are set near the web, and the females can sit on top of it guarding it.

Neriene montana near her translucent egg sac.

Neriene montana under her sheet web

I wanted to photograph this Neriene montana in her retreat, tucked underneath a groove in a plastic toy car. I must have touched the web, as she darted out and sat for a few moments in the middle of her sheet web. They are relatively common in the garden at the moment, and they can be easily distinguished from their relative Linyphia triangularis by their boldly annulated legs. Judging by the large size of her abdomen, thin palps and full size this is an adult female. Contrast with a male, wandering in search of females (below). His palps are like black boxing gloves and his abdomen is about the size of its cephalothorax.

Neriene montana egg guarding

The contrasting red background of a kids wheelbarrow, made it easy to spot the egg sac of this Neriene montana female. The yellow eggs are visible through the loose, gauze-like silk wrapping of the egg sac. The female hangs upside down on her hammock web by the egg sac. She may possibly be able to lay more egg batches, as the female lives up to 7 months. Although egg guarding has not been reported in many money spiders and I could find very little on the reproductive behavior of this species, this photo confirms that the eggs may be laid very close to the web and will undoubtedly benefit from the female being nearby.