Gerromorpha is an infraorder of insects in the "true bug" order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 Hemiptera

Hemiptera

Hemiptera is an order of insects most often known as the true bugs , comprising around 50,000–80,000 species of cicadas, aphids, planthoppers, leafhoppers, shield bugs, and others...

. These "typical" bugs (suborder Heteroptera

Heteroptera

Heteroptera is a group of about 40,000 species of insects in the Hemiptera. Sometimes called "true bugs", that name more commonly refers to Hemiptera as a whole, and "typical bugs" might be used as a more unequivocal alternative since among the Hemiptera the heteropterans are most consistently and...

) are commonly called semiaquatic bugs or shore-inhabiting bugs. The Ochteroidea of the true water bugs (infraorder Nepomorpha

Nepomorpha

Nepomorpha is an infraorder of insects in the "true bug" order . They belong to the "typical" bugs of the suborder Heteroptera. Due to their aquatic habits, these animals are known as true water bugs. They occur all over the world outside the polar regions, with about 2,000 species altogether...

, a far more advanced lineage) are also found in shore habitat, while Gerromorpha are actually most often encountered running around on the water surface, being kept from sinking by surface tension

Surface tension

Surface tension is a property of the surface of a liquid that allows it to resist an external force. It is revealed, for example, in floating of some objects on the surface of water, even though they are denser than water, and in the ability of some insects to run on the water surface...

 and their water-repellent legs. Well-known members of the Gerromorpha are the namesake Gerridae (water striders).

Systematics

The 8 family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 families that are usually recognized are arranged in 4 superfamilies. The 2 small or monotypic

Monotypic

In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

 ones of these are basal lineages, the two larger ones form a more advanced clade

Clade

A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

. The phylogenetic sequence of superfamilies and families of Gerromorpha is:

• Mesovelioidea – water treaders
  • Madeoveliidae (sometimes included in Mesoveliidae)
  • Mesoveliidae
• Hebroidea – velvet bugs
  • Hebridae (Hyrcaninae might arguably be considered a good family as the superfamily is monotypic otherwise.)
• Hydrometroidea
  • Paraphrynoveliidae
  • Hydrometridae
    Hydrometridae
    Hydrometridae is a family of semi-aquatic insects, known as marsh treaders or water measurers. They have a characteristic elongated head and body which makes them resemble a yardstick for measuring the water surface.-Appearance:...
    
     – water measurers
  • Macroveliidae
• Gerroidea
  • Hermatobatidae
  • Gerridae – water striders
  • Veliidae
    Veliidae
    Veliidae is a family of predatory insects in the suborder Heteroptera. They are commonly known as riffle bugs, smaller water striders or broad-shouldered water striders because the segment immediately behind the head is wider than the rest of the abdomen, unlike in the typical water striders ,...
    
    – riffle bugs