Continued
Identification:
Adult spider beetles are minute oval or cylindrical insects with long legs resembling giant mites or small spiders. The head is often hidden when viewed from above. They are 1/16 to 3/16 inch long with long filamentous antennae (usually 11 segmented) arising on the front of the head close together at the base. Most are brownish-black with a large, globe-like abdomen and the prothorax (first segment behind the head) constricted at the base of the wing covers. Larvae are C-shaped or grub-like and cream-coloured with short legs. The segmented abdomen contains many long hairs.

Life Cycle and Habits:
The female lays about 100 opalescent, sticky eggs, singly or in small groups, over a period of 3 to 4 weeks. Food and debris adhere to the eggs. The fleshy larva (which can grow up to 1/8 inch long), covered with fine hairs, is strongly curved, cream coloured and rolls up into a tight ball when disturbed. It can chew its way through sacking, cellophane, or cardboard, and can hollow out a chamber in adjacent woodwork when making a place in which to pupate. Pupation takes place in a tough, spherical, thin-walled cocoon. The adult may remain in this cocoon as long as 3 weeks after emergence (Hickin, 1964). Howe (1943) found that at 21°C (70°F) and 70% relative humidity, the eggs hatched in 8.6 days; the 3 larval instars required 59.9 days; the pupal stage, 15.9 days; the pre-emergence period (adult in cocoon), 9.5 days; and the total life cycle, from egg to the adult leaving the cocoon, 93.9 days.

Click here to continue