GERRIDAE HEMIPTERA TAXIDERMY |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
Hymenoptera of the world(PDF)
CLICK FOR DOWNLOAD (PDF) ---------------------------------
KINGDOM : Animalia
PHYLUM : Arthropoda
CLASS : Insecta
ORDER : Hemiptera
SUBORDER : Heteroptera
INFRAORDER : Gerromorpha
SUPERFAMILY : Gerroidea
FAMILY : Gerridae
--------------------------------- Spiders around the home & yard (PDF)![]() CLICK FOR DOWNLOAD (PDF) |
GERRIDAE HEMIPTERA
Gerridae is a family of insects in the order Hemiptera, commonly known as water striders, water bugs, pond skaters, water skippers, or jesus bugs.
Consistent with the classification of Gerridae as true bugs (i.e., sub-order Heteroptera), gerrids have a mouthpart evolved for piercing and sucking,
gerrids distinguish themselves by having the unique ability to walk on water. Gerridae, or water striders, are anatomically built to transfer their
weight to be able to run on top of the water's surface. As a result, one could likely find water striders present in any pond, river, or lake. Scientists
have identified over 1,700 species of gerrids, 10% of them being marine.
While 90% of Gerridae are freshwater bugs, it is the oceanic Halobates that make the family quite exceptional among insects. The genus Halobates
was first heavily studied between 1822 and 1883 when Buchanan-White collected several different species during the Challenger Expedition.
Around this time, Eschscholtz discovered three species of Family Gerridae, Order Hemiptera, bringing attention to the species even though little of
their biology was known. Since then, the Gerridae have been continuously studied due to their ability to walk on water and unique social
characteristics. Small gerrids have frequently been confused with the other semiaquatic bugs, Veliidae. The most consistent characteristic used to
separate these two families are internal genitalia differences. Since internal genitalia require specific training and tools to identify, it is almost
impossible to tell a member of the Gerridae apart from a member of the Veliidae by external visual cues. One must study their habitat and behaviors
to properly differentiate the two without looking at their specific anatomy.
Family Gerridae are physically characterized by having hydrofuge hairpiles, retractable preapical claws, and elongated legs and body.
Hydrofuge hairpiles are small, hydrophobic microhairs. These are tiny hairs with more than one thousand microhairs per mm. The entire body is
covered by these hairpiles, providing the water strider resistance to splashes or drops of water. These hairs repel the water, preventing drops
from weighing down the body.
Some water striders have wings present on the dorsal side of their thorax, while other species of Gerridae do not- particularly Halobates. Water striders
(Gerridae) experience wing length polymorphism that has affected their flight ability and evolved in a phylogenetic manner where Gerrid populations
are either long-winged, wing-dimorphic, or short-winged. Wing dimorphism consists of summer Gerrid populations evolving different length wings than
winter populations within the same species. Habitats with rougher waters are likely to hold gerrids with shorter wings while habitats with calm waters
are likely to hold long-winged gerrids. This is due to potential for damage of the wings and ability for dispersal.
Water striders are able to walk on top of water due to a combination of several factors. Water striders use the high surface tension of water and long,
hydrophobic legs to help them stay above water. Water molecules are polar and this causes them to attract to each other. The attractive nature results in
the formation of a film-like layer at the top of water. This top layer has gravity acting downward in addition to the water molecules below pulling down
the upper molecules. This combination creates surface tension.
Gerridae are territorial insects and make this known by their vibration patterns. Both female and male adult Gerridae hold separate territories, though
usually the male territories are larger than the female. During the mating season, gerrids will emit warning vibrations through the water and defend
both their territory and the female in it. Even though gerridae are very conspicuous, making their presence known through repel signals, they often live
in large groups. These large groups usually form during the non-mating season since there is less need to compete. Instead of competing to reproduce,
water striders can work together to obtain nutrition and shelter outside of the mating season. Water striders will attempt to disperse when these
groups become too dense. They do so by flying away or cannibalizing.
|