''Hemirrhagus'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of Mexican

tarantulas Tarantulas comprise a group of large and often hairy spiders of the Family (biology), family Theraphosidae. , 1,100 species have been identified, with 166 genera. The term "tarantula" is usually used to describe members of the family Therap ...

that was first described by Eugène Louis Simon in 1903. It is considered a senior synonym of ''Spelopelma''. Species of the genus ''Hemirrhagus'' are 5 to 12 cm long, usually black in colour, the

urticating hair Urticating hairs or urticating bristles are one of the primary defense mechanisms used by numerous plants, almost all New World tarantulas, and various lepidopteran caterpillars. ''Urtica'' is Latin for "nettle" (stinging nettles are in the genu ...

s on the

opisthosoma The opisthosoma is the posterior part of the body in some arthropods, behind the prosoma ( cephalothorax). It is a distinctive feature of the subphylum Chelicerata (arachnids, horseshoe crabs and others). Although it is similar in most respects ...

are arranged in one dorsomedian patch, two dorsal paramedian patches, or two lateral patches. It is unique amongst the theraphosine genera because of the retrolateral coxal heels, the shape of the male

palpal bulb The two palpal bulbs – also known as palpal organs and genital bulbs – are the copulatory organs of a male spider. They are borne on the last segment of the pedipalps (the front "limbs" of a spider), giving the spider an appearance often descr ...

, and the urticating hairs on the abdomen are reduced or completely missing. It is the only genus with epigean,

troglophile Troglofauna are small cave-dwelling animals that have adapted to their dark surroundings. Troglofauna and stygofauna are the two types of subterranean fauna (based on life-history). Both are associated with subterranean environments – troglofa ...

and troglobitic species.

Distribution

Hemirrhagus

are all found in

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

all of them are largely distributed from

Tamaulipas Tamaulipas, officially the Free and Sovereign State of Tamaulipas, is a state in Mexico; one of the 31 states which, along with Mexico City, comprise the 32 federal entities of Mexico. It is divided into 43 municipalities. It is located in nor ...

in the north to

Chiapas Chiapas, officially the Free and Sovereign State of Chiapas, is one of the states that make up the Political divisions of Mexico, 32 federal entities of Mexico. It comprises Municipalities of Chiapas, 124 municipalities and its capital and large ...

in the south, primarily in the mountainous regions of

Sierra Madre Oriental The Sierra Madre Oriental () is a mountain range in northeastern Mexico. The Sierra Madre Oriental is part of the American Cordillera, a chain of mountain ranges (cordillera) that consists of an almost continuous sequence of mountain ranges that ...

, Eje Volcánico Transversal,

Sierra Norte de Oaxaca La Sierra Norte de Oaxaca is a heavily wooded region in the state of Oaxaca, Mexico. It is 62 km from the city of Oaxaca on Federal highway 175, heading east towards Tuxtepec. The region is divided into three districts: Ixtlán, which ha ...

, and Sierra Madre Sur. All of this

are found in individual

caves Caves or caverns are natural voids under the Earth's surface. Caves often form by the weathering of rock and often extend deep underground. Exogene caves are smaller openings that extend a relatively short distance underground (such as rock ...

, some

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), ...

living in the same

cave Caves or caverns are natural voids under the Earth's Planetary surface, surface. Caves often form by the weathering of rock and often extend deep underground. Exogene caves are smaller openings that extend a relatively short distance undergrou ...

. The species are found in cave systems between 100m to 1900m

above sea level Height above mean sea level is a measure of a location's vertical distance (height, elevation or altitude) in reference to a vertical datum based on a historic mean sea level. In geodesy, it is formalized as orthometric height. The zero level ...

. Most of them are found in central Mexico and the northern part of south Mexico. HemirrhagusDistributionMap

Species

* it contains twenty-seven species, all found in

: * ''

Hemirrhagus akheronteus ''Hemirrhagus akheronteus'' is a tarantula which is part of the ''Hemirrhagus'' genus. It is found in Mexico, in the state of Queretaro, and is one of many Mexican cave tarantulas. It was first described by Mendoza and Francke in 2018. It is nam ...

'' Mendoza & Francke, 2018 –

* ''

Hemirrhagus benzaa ''Hemirrhagus'' is a genus of Mexican tarantulas that was first described by Eugène Louis Simon in 1903. It is considered a senior synonym of ''Spelopelma''. Species of the genus ''Hemirrhagus'' are 5 to 12 cm long, usually black in colour, th ...

'' Mendoza, 2014 – Mexico * ''

Hemirrhagus billsteelei ''Hemirrhagus billsteelei'' is a tarantula in the ''Hemirrhagus'' genus of Mexican cave tarantulas. This tarantula is found in the Mexican state of Oaxaca. This tarantula was first described by Mendoza and Francke in 2018, and is named in honou ...

'' Mendoza & Francke, 2018 – Mexico * '' Hemirrhagus cervinus'' (Simon, 1891) (

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * ...

) – Mexico * ''

Hemirrhagus chilango ''Hemirrhagus'' is a genus of Mexican tarantulas that was first described by Eugène Louis Simon in 1903. It is considered a senior synonym of ''Spelopelma''. Species of the genus ''Hemirrhagus'' are 5 to 12 cm long, usually black in colour, th ...

'' Pérez-Miles & Locht, 2003 – Mexico * ''

Hemirrhagus coztic ''Hemirrhagus'' is a genus of Mexican tarantulas that was first described by Eugène Louis Simon in 1903. It is considered a senior synonym of ''Spelopelma''. Species of the genus ''Hemirrhagus'' are 5 to 12 cm long, usually black in colour, th ...

'' Pérez-Miles & Locht, 2003 – Mexico * ''

Hemirrhagus diablo ''Hemirrhagus diablo'' is a tarantula in the ''Hemirrhagus'' genus, it is found in Mexico, in several caves in the state of Morelos. It is named after a cave it is found in, "Cueva del diablo" which translated to "Devil's cave", diablo being devi ...

'' Mendoza & Francke, 2018 – Mexico * ''

Hemirrhagus elliotti ''Hemirrhagus'' is a genus of Mexico, Mexican Theraphosidae, tarantulas that was first described by Eugène Simon, Eugène Louis Simon in 1903. It is considered a senior synonym of ''Spelopelma''. Species of the genus ''Hemirrhagus'' are 5 to 12 c ...

'' ( Gertsch, 1973) – Mexico * '' Hemirrhagus embolulatus'' Mendoza, 2014 – Mexico * '' Hemirrhagus eros'' Pérez-Miles & Locht, 2003 – Mexico * '' Hemirrhagus franckei'' Mendoza, 2014 – Mexico * '' Hemirrhagus gertschi'' Pérez-Miles & Locht, 2003 – Mexico * '' Hemirrhagus grieta'' (Gertsch, 1982) – Mexico * '' Hemirrhagus guichi'' Mendoza, 2014 – Mexico * '' Hemirrhagus kalebi'' Mendoza & Francke, 2018 – Mexico * '' Hemirrhagus lochti'' Estrada-Alvarez, 2014 – Mexico * '' Hemirrhagus mitchelli'' (Gertsch, 1982) – Mexico * '' Hemirrhagus nahuanus'' (Gertsch, 1982) – Mexico * '' Hemirrhagus ocellatus'' Pérez-Miles & Locht, 2003 – Mexico * '' Hemirrhagus papalotl'' Pérez-Miles & Locht, 2003 – Mexico * '' Hemirrhagus perezmilesi'' García-Villafuerte & Locht, 2010 – Mexico * '' Hemirrhagus pernix'' ( Ausserer, 1875) – Mexico * '' Hemirrhagus puebla'' (Gertsch, 1982) – Mexico * '' Hemirrhagus reddelli'' (Gertsch, 1973) – Mexico * ''

Hemirrhagus sprousei ''Hemirrhagus'' is a genus of Mexican tarantulas that was first described by Eugène Louis Simon in 1903. It is considered a senior synonym of ''Spelopelma''. Species of the genus ''Hemirrhagus'' are 5 to 12 cm long, usually black in colour, th ...

'' Mendoza & Francke, 2018 – Mexico * '' Hemirrhagus stygius'' (Gertsch, 1971) – Mexico * '' Hemirrhagus valdezi'' Mendoza, 2014 – Mexico

References

Theraphosidae genera Endemic spiders of Mexico Theraphosidae {{Theraphosidae-stub

Distribution

Species

See also

References