The earless monitor lizard is a semiaquatic, brown lizard native to the Southeast Asian island of Borneo. It is the only living species in the family Lanthanotidae and it is related to the true monitor lizards.
The Helodermatidae or beaded lizards are a small family of lizards endemic to North America today, but formerly more widespread in the ancient past. Traditionally, the Gila monster and the Mexican beaded lizard were the only species recognized, although the latter has recently been split into several species.
Heloderma is a genus of toxicoferan lizards that contains five species, all of which are venomous. It is the only extant genus of the family Helodermatidae.
Arend Friedrich August Wiegmann was a German zoologist and herpetologist born in Braunschweig.
The Mexican beaded lizard is a species of lizard in the family Helodermatidae, one of the two species of venomous beaded lizards found principally in Mexico and southern Guatemala. It and the other member of the same genus, the Gila monster, are the only lizards known to have evolved an overt venom delivery system. The Mexican beaded lizard is larger than the Gila monster, with duller coloration, black with yellowish bands. As it is a specialized predator that feeds primarily upon eggs, the primary use of its venom is still a source of debate among scientists. This venom has been found to contain several enzymes useful for manufacturing drugs in the treatment of diabetes, and research on the pharmacological use of its venom is ongoing.
Toxicofera is a proposed clade of scaled reptiles (squamates) that includes the Serpentes (snakes), Anguimorpha and Iguania. Toxicofera contains about 4,600 species, of extant Squamata. It encompasses all venomous reptile species, as well as numerous related non-venomous species. There is little morphological evidence to support this grouping, however it has been recovered by all molecular analyses as of 2012.
Autarchoglossa is a clade of squamates that includes skinks, anguimorphs, snakes, and relatives. Autarchoglossa is supported as a monophyletic grouping by morphological features in living and extinct lizards and snakes. Some phylogenetic analyses based on molecular features such as DNA sequences in living squamates do not support Autarchoglossa.
The Asian water monitor is a large varanid lizard native to South and Southeast Asia. It is one of the most common monitor lizards in Asia, ranging from coastal northeast India, Sri Lanka, mainland Southeast Asia to Indonesian islands where it lives close to water. It is listed as Least Concern on the IUCN Red List. It was described by Laurenti in 1768 and is among the largest squamates in the world.
Ctenosaura palearis, commonly known as the Motagua spiny-tailed iguana, is a species of spiny-tailed iguana endemic to the Motagua Valley in Guatemala.
The Anguimorpha is a suborder of squamates. The group was named by Fürbringer in 1900 to include all autarchoglossans closer to Varanus and Anguis than Scincus. These lizards, along with iguanians and snakes, constitute the proposed "venom clade" Toxicofera of all venomous reptiles. The oldest definitive record of the group is Dorsetisaurus from the Late Jurassic of Europe and North America.
The Gila monster is a species of venomous lizard native to the Southwestern United States and the northwestern Mexican state of Sonora. It is a heavy, typically slow-moving reptile, up to 56 centimetres/22 inches long, and is the only venomous lizard native to the United States. Its venomous close relatives, the four beaded lizards inhabit Mexico and Guatemala. The Gila monster is sluggish in nature, so it is not generally dangerous and very rarely poses a real threat to humans. Yet, its exaggeratedly fearsome reputation has led to it sometimes being killed, in spite of the species being protected by state law in Arizona.
Ctenosaura acanthura, is a species of iguanid lizard found in eastern Mexico and extreme western Guatemala. The standardized English name is the Mexican spiny-tailed iguana. Confusingly however, an earlier edition of standardized names for Mexican herpetofauna called Ctenosaura acanthura the northeastern spinytailed iguana and applied the name Mexican spinytailed iguana to Ctenosaura pectinata, which was called the western spiny-tailed iguana in the second edition. It has also been referred to as the Veracruz spiny-tailed iguana and Gulf Coast spiny-tailed iguana. It is an egg laying species that is mostly herbivorous, and a moderately large lizard commonly growing over one meter in total length.
The Guatemalan beaded lizard, also called commonly the Motagua Valley beaded lizard, is a highly endangered species of beaded lizard, a venomous lizard in the family Helodermatidae. The species is endemic to the dry forests of the Motagua Valley in southeastern Guatemala, an ecoregion known as the Motagua Valley thornscrub. It is the only allopatric beaded lizard species, separated from the nearest population by 250 km (160 mi) of unsuitable habitat. The Guatemalan beaded lizard is the rarest and most endangered species of beaded lizard, and it is believed that fewer than 200 individuals of this animal exist in the wild, making it one of the most endangered lizards in the world. In 2007, it was transferred from Appendix II to Appendix I of CITES due to its critical conservation status.
Platynota is a polyphyletic group of anguimorph lizards and thus belongs to the order Squamata of the class Reptilia. Since it was named in 1839, it has included several groups, including monitor lizards, snakes, mosasaurs, and helodermatids. Its taxonomic use still varies, as it is sometimes considered equivalent to the group Varanoidea and other times viewed as a distinct group. It is phylogenetically defined as a clade containing Varanidae. It also includes many extinct species.
Monstersauria is a clade of varanoid lizards, defined as all taxa more closely related to Heloderma than Varanus. It includes Heloderma, as well as several extinct genera, such as Estesia, Primaderma and Gobiderma, but it was found to be polyphyletic in the most recent and complete squamate phylogenetic analysis by Reeder et al. (2015).
Helothermine is a toxin from the venom of the Mexican beaded lizard Heloderma horridum horridum. Helothermine inhibits ryanodine receptors, calcium channels and potassium channels. Helothermine can cause lethargy, partial paralysis of rear limbs and lowering of the body temperature.
The Sinaloan dry forests is a tropical dry broadleaf forest ecoregion in western Mexico. It is the northernmost ecoregion of the Neotropical realm.
The Sierra de Álamos–Río Cuchujaqui Flora and Fauna Protection Area, also known as the Sierra de Álamos–Río Cuchujaqui Biosphere Reserve, is a protected area and biosphere reserve in western Mexico. It is located in southeastern Sonora state, along the boundary with Sinaloa and Chihuahua states.
Heloderma alvarezi, the Chiapan beaded lizard or black beaded lizard, is a species of lizard of the Helodermatidae family. It is found in Mexico and Guatemala.
