User:Philcha/Sandbox/Portia schultzi

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 * Salticidae: Diagnostic Drawings Library - Jerzy Proszynski

Reproduction and lifecycle 2
Before courtship, a male Portia spins a small web between boughs or twigs, and he hangs under that and ejaculates on to it. He then soaks the semen into reservoirs on his pedipalps, which are larger than those of females. Females of many spider species, including P. schultzi, emit volatile pheromones into the air, and these generally attract males from a distance.

Among P. schultzi and some other Portias, when adults of the same species but opposite sexes recognise each other, they display at 10 to 30 centimetres. Males usually wait for 2 to 15 minutes before starting a display, but sometimes a female starts a display first. Portias sometimes use "propulsive displays", with which a member threatens a rival of the same species and sex, and unreceptive females also threaten males in this way. A propulsive display is a series of sudden, quick movements including striking, charging, ramming and leaps. In P. schultzi and in some other species, contests between males usually last only 5 to 10 seconds, and only their legs make contact. Contests between Portia females are violent and embraces in P. schultzi typically take 20 to 60 seconds. These occasionally include grappling that sometimes breaks a leg, but more usually the final move is a lunge. Sometimes one knocks the other on her back and the other may be killed and eaten if she does not right herself quickly and run way. If the loser has a nest, the winner takes over and eats any eggs there.

A female P. schultzi that sees a male may approach slowly or wait. The male then walks erect and displaying by waving his legs and palps. If the female does not run away, she gives a propulsive display first. If the male stands his ground and she does not run away or repeat the propulsive display, he approaches and, if she is mature, they copulate. If the female is sub-adult (one moult from maturity), a male may cohabit in the female's capture web. Portias usually mate on a web or on a dragline made by the female. P. schultzi typically copulates for about 100 seconds, while other genera can take several minutes or even several hours.

Females of P. schultzi, like those of P. labiata, try to kill and eat their mates during or after copulation, by twisting and lunging. The males wait until the females have hunched their legs, making this attack less likely. Males also try to abseil from a silk thread to approach from above, but females may manoeuvre to get the higher position. If the female moves at all, the male leaps and runs away.

Before being mature enough to mate, females of P. shultzi and also P. labiata mimic adult females to attract males as prey.

P. schultzi usually lays eggs on dead, brown leaves about 20 millimetres long, suspended near the top of its capture web, and then cover the eggs with a sheet of silk. If there is no dead leaf available, the female will make a small horizontal silk platform in the capture web, lay the eggs on it, and then cover the eggs. P. schultzi has been seen laying eggs in a rolled-up leaf in a web of Ischnothele karschi.

For moulting, all Portias spin a horizontal web whose diameter is about twice the spider's body length and is suspended only 1 to 4 millimetres below a leaf. The spider lies head down, and often slides down 20 to 30 millimetres during moulting. Portias spin a similar temporary web for resting. Like all arthropods, spiders moult and, after hatching, the life stage before each moult is called an "instar". The distinctive tufts of P. schultzi juveniles appear in the third instar.

P. schultzi exuviae (discarded "skins") have been found both in their own webs and in those of I. karschi, which has suggested that P. schultzi moults in the open. In one case, while its new skin was still pale and soft, its spinnerets were still stuck in the discarded skin, and the spider slowly twirled for about 90 seconds until it was free. The spider's body then darkened quickly to the normal colouration, and some time later the spider hung in its usual upside-down posture in the web.