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water scavenger beetle

Hydrophilus ensifer


Species variable length 30-37 mm, dorsally slightly convex shape and flat ventrally, intensely dark brownish green, glossy black to the naked eye; palps and antennae reddish yellow. Glabrous dorsally, ventrally pubescent reddish yellow robe; abdominal ventrite completely covered the first, second glabra leaves a triangular area and in the following the garment to restrict lateral margins. Fifth joint of the protarsos short, broad and subrectangular male, with its straight inner margin and margins suckers are not restricted; internal evidently wider unequal protarsales long nails and the outer, the knuckles 2 to 4 with its straight inner margin. Mesoventrito keel with a shallow and not very wide in its anterior half groove, Thorn metaventrito only reaches half of the second abdominal ventrite; Finally ventrite strongly raised in the center to form a keel (exceptionally without keel).


These species live in still waters with abundant submerged vegetation in shallow temporary ponds with aquatic flowering and emergent grasses, and it is not uncommon to see them fly to the light during the summer.

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Spotted by

Alajuela, Costa Rica

Spotted on Jun 15, 2014
Submitted on Jun 21, 2014

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