Other Common Names
Marsh Treaders
Water Treaders
Pond-skaters
all the above names refer to the family in general
Explanation of Names
Hydrometra: from the Greek "hydor" (water) + "metron" (measure); refers to the slow and deliberate movement of these insects, which appear to "measure the water" as they walk across its surface
Numbers
9 species in North America listed at
nearctica.com:
aemula, austalis, barei, beameri, consimilis, hungerfordi, lilianis, martini and
wileyiSize
body length 7-12 mm; most are about 8 mm
Identification
Adults resemble tiny
walkingsticks. Body and legs
very long and slender, usually grayish. Usually wingless. Head
long and slender, the eyes bulging and located slightly behind the middle of head. Antennea 4-segmented. Tarsi 3-segmented.
(1)Habitat
Found on the edges of ponds either on aquatic vegetation or walking slowly over the surface of the water.
(1)Season
Late spring and summer in the northern states.
Food
Nymphs and adults eat small aquatic insects and crustaceans found on the surface vegatation of the water. Typical prey includes midges, mosquito larvae, bloodworms, waterfleas, springtails.
Life Cycle
Eggs are laid either on vertical surfaces of plant stems or on ground several centimetres above water level.
See Also
waterscorpions (Nepidae) in the genus
Ranatra are larger (more than 18 mm), have a long abdominal breathing tube, and are usually seen under the water surface or on aquatic vegetation - not walking on the water surface
walkingsticks (Phasmatodea) are larger and live on land in forested areas
thread-legged bugs (Emesinae) live on land and have relatively short heads
stilt bugs (Berytidae) live on land and have short heads with clubbed antennae
Print References
"Peterson's Field Guide to Insects" p. 125
(1)
"American Insects: A Handbook of the Insects of America North of Mexico" p. 277
(2)Internet References
The Insects of Cedar Creek, Minnesota has some info and a photo of
H. martini.
The Florda Center for Library Automation has an interesting
PDF report on rearing
Hydrometra in the lab.
live adult image of
Hydrometra species, plus description and habitat (U. of Michigan)
adult images of
Hydrometra species, plus description and habitat (Valley City State U., North Dakota)
