Byrrhoidea is a superfamily of beetles belonging to
Elateriformia
Elateriformia is an infraorder of polyphagan beetles. The two largest families in this group are buprestids, of which there are around 15,000 described species, and click beetles, of which there are around 10,000 described species.
The infraor ...
that includes several families which are either aquatic or associated with a semi-aquatic habitat. Other than the superfamily Hydrophiloidea, most of the remaining
Polyphaga
Polyphaga is the largest and most diverse suborder of beetles. It comprises 144 families in 16 superfamilies, and displays an enormous variety of specialization and adaptation, with over 350,000 described species, or approximately 90% of the be ...
n beetles which are aquatic are in this superfamily.
Description
Adults of many Byrrhoidea have exocone eyes (with expanded corneal lens). The anterior edge of the scutellar shield is often abruptly elevated (except in Psephenidae and Cneoglossidae). A variety of byrrhoids have the first three abdominal ventrites solidly fused together.
Larvae of most Limnichiidae have one pair of anal hooks on the tenth abdominal segment, while Cneoglossidae and Ptilodactylidae have three or more hooks on each side of this segment. Larvae of Lutrochidae and Elmidae, as well as the limnichiid genus ''Hyphalus'', have anal gill tufts. Almost all byrrhoid larvae have anterior abdominal spiracles that are biforous (or bilabiate) in shape.
The degree of
wing
A wing is a type of fin that produces lift while moving through air or some other fluid. Accordingly, wings have streamlined cross-sections that are subject to aerodynamic forces and act as airfoils. A wing's aerodynamic efficiency is e ...
development varies among Byrrhoidea, with macroptery (wings fully developed), brachyptery (wings reduced), microptery (wings reduced to small remnants) and
aptery
Aptery is the anatomical condition of an animal completely lacking any kind of wings. An animal with this condition is said to be apterous.
Most animal species belong to and are phylogenetic descendants of apterous taxa. These groups are said to ...
(no wings) all occurring in the superfamily. Within family
Elmidae
Elmidae, commonly known as riffle beetles, is a family of beetles in the superfamily Byrrhoidea described by John Curtis in 1830. Both adults and larvae are usually aquatic, living under rocks in fast-flowing shallow areas of streams, such as r ...
, subfamily
Larainae
Larainae is a subfamily of riffle beetles in the family Elmidae. There are more than 20 genera and 160 described species in Larainae.
Genera
These 28 genera belong to the subfamily Larainae:
* '' Disersus'' Sharp, 1882
* '' Dryopomorphus'' Ham ...
has only macropterous wings, while other wing types are common in subfamily
Elminae
Elminae is a subfamily of riffle beetles in the family Elmidae. There are at least 120 genera and more than 1,300 described species in Elminae.
Genera
These genera belong to the subfamily Elminae.
* '' Aesobia'' Jäch, 1982
* '' Amazonopsis'' ...
. Within family Dryopidae, the genera with aquatic or semiaquatic adults are almost always macropterous, while genera with terrestrial adults are almost always apterous and the subterranean ''
herbivorous
A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpar ...
, feeding on
algae
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular micr ...
,
moss
Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta ('' sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and ...
,
liverworts
The Marchantiophyta () are a division of non-vascular land plants commonly referred to as hepatics or liverworts. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of ...
,
lichens
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.grass
Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns a ...
roots.
Phylogeny
Byrrhoidea in its current state may not be
monophyletic
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gr ...
. Multiple studies have found
Buprestoidea
Buprestoidea is a superfamily of beetles.
It contains two families:
* Buprestidae Leach 1815, the jewel beetle
Buprestidae is a family of beetles known as jewel beetles or metallic wood-boring beetles because of their glossy iridescent colo ...
to be nested within it. Recent phylogenies have split out the grouping Dryopoidea, including Dryopidae, Elmidae, Limnichidae, Heteroceridae, Chelonariidae, Eulichadidae, Callirphidae, Ptilodactylidae and the extinct family Mastigocoleidae., with phylogenies finding the group more closely related to
Elateroidea
The Elateroidea are a large superfamily of beetles. It contains the familiar click beetles, fireflies, and soldier beetles and their relatives. It consists of about 25,000 species.
Description
Elateroidea is a morphologically diverse group, ...