Notomicrus tenellus ( Clark, 1863 )

Hendrich, Lars & Balke, Michael, 2004, Aquatic Coleoptera Of Singapore: Species Richness, Ecology And Conservation #, Raffles Bulletin of Zoology 52 (1), pp. 97-145 : 113

Notomicrus tenellus ( Clark, 1863)

Hydroporus tenellus Clark, 1863: 427 .

Hydroporus politus MacLeay, 1871: 124 .

Notomicrus laevigatus Sharp, 1882: 260 .

Notomicrus punctulatus Fauvel, 1903: 245 .

Notomicrus tenellus (Clark) - Balfour-Browne, 1939b: 97; Vazirani, 1977: 2; Balke et al., 1998: 73; Hebauer et al., 1999: 337.

Material known. – Number? – « Singapore » cited in Balfour-Browne (1939b). Specimens not seen.

Distribution. – West Malaysia, Indonesia: Java, Philippines, Papua New Guinea, Salomon Islands and Australia ( Vazirani, 1977); Singapore ( Balfour-Browne, 1939b).

Ecology. – A lentic species which occurs in various types of habitats such as pools, ponds and swamps. The beetles generally occur in very shallow water among rotten leaves adjacent to the shoreline. Because of their small size (length <2.0 mm) the beetles may be overlooked in the field when using a large aquatic dip net instead of a fine strainer ( Balke et al., 1998).

FAMILY DYTISCIDAE

The Dytiscidae is a large family with more than 3792 described species worldwide ( Nilsson, 2001). In Singapore they are found in virtually all freshwater habitats, being most common in the littoral zones of swamps, pools, lakes and ditches, but less frequently in streams and rivers, and water bodies where fish are present. Both larvae and adults are aquatic. The pupal stage is spent on land in a mud cell. Eggs are usually laid beneath the water surface attached to aquatic plants. The larva passes through three larval instars. The larval development of most Southeast Asian dytiscids is still unknown. Both larvae and adults must periodically travel to the water surface to obtain atmospheric air through their posterior spiracles. However, adults can prolong submergence by using a bubble of air under their elytra as a plastron. Both larvae and adults are carnivorous. The prey items of the smaller species (e.g., Hydrovatus , Leiodytes , Copelatus , Lacconectus ) include larvae of mosquitoes, chironomids and Daphnia ; the larger species (e.g., Cybister ) feed on small fishes and tadpoles as well.

SUBFAMILY HYDROPORINAE

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