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The three pairings proceeded as follows:
Female A, housed in a custom-made tank:
28/08/05: Moulted.
11/09/05: Mated. Courtship was a very deliberate affair with the male beginning courtship almost immediately on contact with the females silk. The female responded by appearing at her burrow entrance and drumming her first pair of legs in response to the male. They remained calm throughout as the male secured the females chelicerae (H. albostriatum don't have tibial hooks or spurs but rather a blunt-ended protrusion that sits at the base of the females' fang in order to lift her into position). Palp insertions were brief and followed by characteristic epigynum rubbing by the female. The reason Ornithoctoninae females show this post-mating behaviour is somewhat of a mystery. After mating the female is often seen to frantically rub her underside (around the epigastric furrow) with her third and fourth pair of legs while moving the chelicerae in a 'chewing' motion (much like a speeded up version of cleaning). Explanations include massaging the uterus externus back into position or displacement activity - a conflict between mating behaviour and prey capture (the male as prey). In such a case the behaviour "jumps over" to a completely other behaviour complex (cleaning), because she is not only rubbing her genital region but the complete abdomen, spinnerets and the chelicerae (von Wirth, 1996).
Over the following four months, temperatures remained on average around 70-75oF and the substrate remained moist at lower levels of the enclosure and dry at ground level. Feeding wasn't increased and prey was offered approx. once a month consisting of crickets and lobster cockroaches Nauphoeta cinerea with the occasional deaths head cockroach Blaberus discoidales.
28/01/06: Found with eggsac. Burrow entrance left open (no noticeable silk or substrate across the entrance). As with most females that are incubating an egg-sac, feeding was suspended and the container disturbed as little as possible. The egg-sac could clearly be seen through the side of the enclosure (fossorial tanks are ideal for viewing the spider inside its burrow chamber). The female was often seen to move the egg-sac up and down the burrow and sometimes at the front of the container at ground level (warming the egg-sac at the point closest to the heat source).
13/04/06: Found with nymphs that spent their time at ground level, again, probably at the warmest part of the enclosure (they would bolt down the females burrow at the slightest disturbance). The egg-sac had been discarded at burrow entrance and was opened to find several black eggs and moulted skins of the surviving nymphs. These eventually moulted into spiderlings - some at ground level, some in the females' burrow chamber. 01/05/06: Separated spiderlings, 50 in total.
The other two breedings were similar:
Female B, housed in a sweet jar:
19/09/05: Mated - this was the smallest female but very eager to mate, male using both palps.
14/04/06: Found with egg-sac.
01/05/06: Egg-sac discarded, destroyed by mould.
Lack of adequate air-flow through the lower section (the only air holes were in the lid) of this container probably resulted in the egg-sac being destroyed by mould. Lack of visibility into the container so no evidence of the female moving and warming the egg-sac at the burrow surface.
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