family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
of the wall lizards, true lizards, or sometimes simply lacertas, which are native to
Afro-Eurasia
Afro-Eurasia (also Afroeurasia and Eurafrasia) is a landmass comprising the continents of Africa, Asia, and Europe. The terms are compound (linguistics), compound words of the names of its constituent parts. Afro-Eurasia has also been called th ...
. It is a diverse family with at about 360
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
in 39
genera
Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...
. They represent the dominant group of reptiles found in Europe.
Habitat
The European and Mediterranean species of lacertids live mainly in
forest
A forest is an ecosystem characterized by a dense ecological community, community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, ...
and scrub habitats. ''Eremias'' and ''Ophisops'' species replace these in the
grassland
A grassland is an area where the vegetation is dominance (ecology), dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes such as clover, and other Herbaceo ...
and
desert
A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the la ...
habitat
In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...
s of Asia. African species usually live in rocky, arid areas. ''
Holaspis
''Holaspis'' is a genus of equatorial African lizards in the family Lacertidae. These lizards are capable of gliding flight for distances of 30 meters (98 feet).
Etymology
The Neo-Latin word "''Holaspis'' " is derived from the Greek words " as ...
'' species are among the few
arboreal
Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally (scansorial), but others are exclusively arboreal. The hab ...
lacertids, and its two species, ''
Holaspis guentheri
''Holaspis guentheri'', also commonly known as the neon blue-tailed tree lizard, the sawtail lizard, and the western neon blue-tailed tree lizard www.reptile-database.org. is a species of lizard in the family Lacertidae. The species is native t ...
'' and ''
Holaspis laevis
''Holaspis laevis'', commonly known as the eastern serrate-toed tree lizard or eastern neon blue-tailed tree lizard is a species of lizard occurring in Sierra Leone, Ghana, Nigeria, Cameroon, Equatorial Guinea, Democratic Republic of the Congo, U ...
'', are gliders (although apparently poor ones), using their broad tail and flattened body as an
aerofoil
An airfoil (American English) or aerofoil (British English) is a streamlined body that is capable of generating significantly more lift than drag. Wings, sails and propeller blades are examples of airfoils. Foils of similar function designed ...
.
Description
Lacertids are small to medium-sized lizards. Most species are less than 9cm long, excluding the tail. The largest living species, ''
Gallotia stehlini
The Gran Canaria giant lizard (''Gallotia stehlini'') is a species of lizard in the family Lacertidae. The species is found in the Canary Islands.
Etymology
The specific name, ''stehlini'', is in honor of Swiss paleontologist Hans Georg Stehl ...
'', reaches 46cm, and some extinct forms were larger still. They are primarily
insectivorous
A robber fly eating a hoverfly
An insectivore is a carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects.
The first vertebrate insectivores we ...
. An exception is '' Meroles anchietae'', one of the few wall lizards that regularly eat
seed
In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...
s – an appropriate food for a lizard of the harsh
Namib Desert
The Namib ( ; ) is a coastal desert in Southern Africa. According to the broadest definition, the Namib stretches for more than along the Atlantic coasts of Angola, Namibia, and northwest South Africa, extending southward from the Carunjamba Ri ...
.
Lacertids are remarkably similar in form, with slender bodies and long
tail
The tail is the elongated section at the rear end of a bilaterian animal's body; in general, the term refers to a distinct, flexible appendage extending backwards from the midline of the torso. In vertebrate animals that evolution, evolved to los ...
s, but have highly varied patterns and colours, even within the same species. Their scales are large on the head, which often also has
osteoderm
Osteoderms are bony deposits forming scales, plates, or other structures based in the dermis. Osteoderms are found in many groups of extant and extinct reptiles and amphibians, including lizards, crocodilians, frogs, temnospondyls (extinct amph ...
s, small and granular on the back, and rectangular on the underside. Most species are
sexually dimorphic
Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...
, with the males and females having different patterns.
At least eight species from the
Caucasus
The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, i ...
are
parthenogenetic
Parthenogenesis (; from the Greek + ) is a natural form of asexual reproduction in which the embryo develops directly from an egg without need for fertilization. In animals, parthenogenesis means the development of an embryo from an unfertiliz ...
,Darevskii IS. 1967. Rock lizards of the Caucasus: systematics, ecology and phylogenesis of the polymorphic groups of Caucasian rock lizards of the subgenus ''Archaeolacerta''. Nauka: Leningrad n Russian: English translation published by the Indian National Scientific Documentation Centre, New Delhi, 1978Tarkhnishvili DN (2012) Evolutionary History, Habitats, Diversification, and Speciation in Caucasian Rock Lizards. In: Advances in Zoology Research, Volume 2 (ed. Jenkins OP), Nova Science Publishers, Hauppauge (NY), p.79-120 and three species give birth to live young, including the
viviparous
In animals, viviparity is development of the embryo inside the body of the mother, with the maternal circulation providing for the metabolic needs of the embryo's development, until the mother gives birth to a fully or partially developed juve ...
Lacertids are suspected to have originated in Europe, due to their earliest fossils being found in the region, alongside those of their
sister group
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree.
Definition
The expression is most easily illustrated by a cladogram:
Taxon A and ...
, the extinct
Eolacertidae
Eolacertidae is an extinct family of lacertoid lizards known from the Paleocene and Eocene of Europe. They are the closest known relatives of Lacertidae.
Genera
* '' Eolacerta'' Nöth, 1940 Conglomérat de Cernay, France, Paleocene, Tiene ...
. Fossils possibly attributable to lacertids are known from the
Paleocene
The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), ...
of France and Belgium. The oldest definitive lacertid is known from the early
Eocene
The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...
(
Ypresian
In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by th ...
Paris Basin
The Paris Basin () is one of the major geological regions of France. It developed since the Triassic over remnant uplands of the Variscan orogeny (Hercynian orogeny). The sedimentary basin, no longer a single drainage basin, is a large sag in ...
. Lacertids dispersed into Asia by the early
Oligocene
The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...
. The timing of the colonisation of Africa is uncertain, ranging from the Eocene to the
Miocene
The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...
.
Classification
The classification into subfamilies and tribes below follows one presented by Arnold ''et al.'', 2007, based on their
phylogenetic
In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...
analysis.
Family Lacertidae
*Subfamily Gallotiinae
**Genus ''
Gallotia
The genus ''Gallotia'' are the lacertids (wall lizards) of the Canary Islands. This genus consists of a group that has been evolving there ever since the first islands emerged from the sea over 20 million years ago. The endemic species and sub ...
Holaspis
''Holaspis'' is a genus of equatorial African lizards in the family Lacertidae. These lizards are capable of gliding flight for distances of 30 meters (98 feet).
Etymology
The Neo-Latin word "''Holaspis'' " is derived from the Greek words " as ...
'' (2 species)
***Genus ''
Ichnotropis
''Ichnotropis'' is a genus of African lizards in the family Lacertidae. Species in the genus ''Ichnotropis'' are commonly called rough-scaled lizards."''Ichnotropis'' ". The Reptile Database. www.reptile-database.org.
Species
The following six s ...
Mesalina
''Mesalina'' is a genus of wall lizards of the family Lacertidae.
Species
The following 20 described species are recognized as being valid."''Mesalina'' ". The Reptile DatabaseReptile-database.cz/ref>
*'' Mesalina adramitana'' – Hadramaut sa ...
Philochortus
''Philochortus'' is a genus of lizards of the Family (biology), family Lacertidae. Species of this genus are distributed in Egypt, Algeria, Libya, Mali, Niger, Ethiopia, Djibouti, Eritrea, Somalia, Kenya, Yemen, and Saudi Arabia.
Etymology
''Phi ...
Darevskia
''Darevskia'' is a genus of wall lizards of the family (biology), family Lacertidae. Member species are native to the Caucasus, Iran and Turkey, living in forest and grassy habitats with numerous rock outcrops. Among rock lizards, seven parthenog ...
Podarcis
''Podarcis'' is a genus of lizards, known colloquially as wall lizards, in the Family (biology), family Lacertidae. Its members look very similar to lizards of the genus ''Lacerta (genus), Lacerta'', to which they were considered to belong until ...
Takydromus
''Takydromus'' is a genus of lizards, commonly called grass lizards or oriental racers. Species of the genus ''Takydromus'' are Endemism, endemic to a large part of Asia. Members of this genus are noticeable because of their slender appearance ...
'' (24 species)
***Genus '' Teira'' (1 species)
***Genus '' Timon'' (6 species)
***Genus '' Vhembelacerta'' (1 species)
***Genus '' Zootoca'' (2 species)
The latest extensive phylogenetic lacertid tree was made by Baeckens ''et al.'' in 2015.
Baltic amber
Baltic amber or succinite is amber from the Baltic region, home of its largest known deposits. It was produced sometime during the Eocene epoch, but exactly when is controversial. It has been estimated that this forested region provided the re ...
Mallorca
Mallorca, or Majorca, is the largest of the Balearic Islands, which are part of Spain, and the List of islands in the Mediterranean#By area, seventh largest island in the Mediterranean Sea.
The capital of the island, Palma, Majorca, Palma, i ...
,
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Quercycerta'' France, Eocene
* †'' Janosikia'' Germany, Miocene
* †'' Escampcerta'' France, Eocene
* †'' Mediolacerta'' France, Germany, Oligocene
* †'' Pseudeumeces'' France, Germany, Spain, Oligocene-Miocene
* †'' Amblyolacerta'' France, Czech Republic, Miocene
* †'' Ligerosaurus'' France, Miocene
* †'' Miolacerta'' Germany, Austria, Czech Republic, Oligocene-Miocene
* †'' Edlartetia'' Augé and Rage 2000 Germany, France Austria, Miocene
* †'' Escampcerta'' France, Eocene
* †'' Cernaycerta''? France, Paleocene (questioned by some authors)
* †'' Dormaalisaurus'' France, Belgium, Spain, Eocene