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(= HELODIDAE, CYPHONIDAE)Code QC200000Larvae elongate to subovate, 5-15 mm in size when mature. Scirtid larvae are easily recognised by their extremely long, multisegmented antenna (10 to >100 segments). Moderate to small (3-10 mm), unique not only among the Coleoptera, but also among all holometabolous larvae. Scirtids also possess five retractile anal gill filaments, 5 segmented legs bearing spinous setae and a single claw (tarsungulus). The buccal cavity shows very complex organisation, including a filtering apparatus. Larval scirtids (Polyphaga: Eucinetoidea) filter fine particles from the water. Particles are 'sorted' via comb hairs on the maxilla before being transferred to the hypopharynx, where they are crushed and packed into a ball via movements of the hypopharynx against the molar area of the mandibles. Scirtids occur in both lentic and lotic habitats, including quite stagnant conditions. Scirtids are most abundant and diverse in the cool temperate regions of Australia, though they occur in the north also. Around 70 Australian species are currently recognised. References: Lawrence, J.F. and Britton, E.B. (1991) Coleoptera. pp. 543-683. In: CSIRO, Insects of Australia. Volume 2. Melbourne University Press, Carlton, Victoria. LeSage, L. (1991) Helodidae (Eucinetoidea) pp. 311-312. In: Stehr, F.W. (ed.) Immature Insects. Volume 2. Kendall/Hunt Publishing Company, Dubuque, Iowa. |