''Hemirrhagus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Mexican Mexican may refer to: Mexico and its culture *Being related to, from, or connected to the country of Mexico, in North America ** People *** Mexicans, inhabitants of the country Mexico and their descendants *** Mexica, ancient indigenous people ...

tarantulas Tarantulas comprise a group of large and often hairy spiders of the family Theraphosidae. , 1,040 species have been identified, with 156 genera. The term "tarantula" is usually used to describe members of the family Theraphosidae, although m ...

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 to a ...

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 In vertebrate anatomy, hip (or "coxa"Latin ''coxa'' was used by Celsus in the sense "hip", but by Pliny the Elder in the sense "hip bone" (Diab, p 77) in medical terminology) refers to either an anatomical region or a joint. The hip region is ...

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 – troglofau ...

and

troglobitic A troglobite (or, formally, troglobiont) is an animal species, or population of a species, strictly bound to underground habitats, such as caves. These are separate from species that mainly live in above-ground habitats but are also able to live u ...

species.

Distribution

Hemirrhagus

are all found in

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

all of them are largely distributed from

Tamaulipas Tamaulipas (), officially the Free and Sovereign State of Tamaulipas ( es, Estado Libre y Soberano de Tamaulipas), is a state in the northeast region of Mexico; one of the 31 states which, along with Mexico City, comprise the 32 Federal Entiti ...

in the north to

Chiapas Chiapas (; Tzotzil language, Tzotzil and Tzeltal language, Tzeltal: ''Chyapas'' ), officially the Free and Sovereign State of Chiapas ( es, Estado Libre y Soberano de Chiapas), is one of the states that make up the Political divisions of Mexico, ...

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 f ...

, 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 has ...

, and Sierra Madre Sur. All of this

are found in individual

caves A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...

, some

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

living in the same

cave A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...

. The species are found in

cave systems A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...

between 100m to 1900m

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

. 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'' 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, the ...

'' Mendoza, 2014 – Mexico * '' Hemirrhagus billsteelei'' Mendoza & Francke, 2018 – Mexico * '' Hemirrhagus cervinus'' (Simon, 1891) ( type) – Mexico * '' Hemirrhagus chilango'' Pérez-Miles & Locht, 2003 – Mexico * '' Hemirrhagus coztic'' Pérez-Miles & Locht, 2003 – Mexico * '' Hemirrhagus diablo'' Mendoza & Francke, 2018 – Mexico * ''

Hemirrhagus elliotti ''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, the ...

'' ( 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 ''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 ...

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

Hemirrhagus valdezi ''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 ...

'' Mendoza, 2014 – Mexico

References

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

Distribution

Species

See also

References