Volcano rabbit

Romerolagus diazi was first described by the head of the Mexican Geographical and Exploring Commission, Fernando Ferrari-Pérez, in 1893 as a member of the hares (genus Lepus), using the scientific name Lepus diazi and common name (volcano rabbit). Since then, the scientific name and authority of the volcano rabbit has been Romerolagus diazi (Ferrari-Pérez in A. Díaz, 1893). Another common name, teporingo, likely derives from Classical Nahuatl, combining (), () and the suffix - referring to location. Phylogeny No subspecies of the volcano rabbit are recognized, alongside Pentalagus, Pronolagus, and the extinct Alilepus and Palaeolagus. The following cladogram is based on mitochondrial genome analysis of the volcano rabbit, the European rabbit, the snowshoe hare (Lepus americanus), and the black-tailed jackrabbit (Lepus californicus), as well as a broader phylogenetic tree produced by biologist Leandro Iraçabal Nunes and colleagues: |2= }} == Characteristics ==

The volcano rabbit is one of the smallest rabbits in the world, The dark coloration of the volcano rabbit's fur blends in with the volcanic soils in its habitat. This adaptation may help it evade predators. Its coat does not change color from one season to the next. However, it does undergo molting in four stages over the course of the year. First, hair is lost, then melanin disappears, then melanin is deposited at the site of hair loss, after which hair regrows. The skull of the volcano rabbit has small triangle-shaped projections from the brow ridge towards the back of the head. It has a long palate, and a distinctly separated interparietal bone. The cheekbones are wide, larger towards the back of the head, and the auditory bullae (bony structures that enclose the external structure of the ear) are large compared to those of other leporids, larger than the foramen magnum (the hole at the base of the skull that the spinal cord passes through). It has a strong curve to its pelvis. The hip bones of the volcano rabbit are more similar to another extinct species, Limnolagus, aside from being thinner and more pronounced towards the front and bottom part of the spine. == Distribution and habitat ==

, one of four volcanoes around which the volcano rabbit lives. Forests of Pinus hartwegii, a species of conifer found in habitats suitable for the rabbit, The plants Festuca tolucensis and Pinus hartwegii are abundant in volcano rabbit habitats. Populations exist elsewhere within the Trans-Mexican Volcanic Belt and in captivity. By 2019, the International Union for Conservation of Nature no longer mentioned the Nevado de Toluca as a current or potential site for the distribution of this species. == Behavior and ecology ==

Volcano rabbit groups consist of between two and five members. The rabbit creates runways similar to those made by microtine rodents to navigate their habitat. Its burrows consist of tunnels with the entrances beneath dense grass clumps or in cracks in the soil, and can have a length of up to and depth of up to under the soil's surface. The reproductive behavior of volcano rabbits has been infrequently observed, with most records coming from captive individuals. Males often select a single female from a group to mate with, though when that mate is removed, they choose another. The mating process begins with the male following closely behind its partner until the female turns around, at which point the two start circling each other. After a few turns, the male mounts the female and begins copulation. The species has a very narrow gestational period. In a 1985 study, all females gave birth between 39 and 41 days after coitus; and Cheyletiella parasitovorax, which is notable as there is usually only one species of Cheyletiella mite found on a given host species. Other species-specific parasites are Boreostrongylus romerolagi, Dermatoxys romerolagi, Lamothiella romerolagi, Anoplocephaloides romerolagi, Cediopsylla tepolita, and Hoplopsyllus pectinatus. == Status and conservation ==

, a highway in the Mexican state of Puebla. The construction of similar highways has contributed to declines in volcano rabbit populations due to habitat fragmentation. The International Union for Conservation of Nature (IUCN) currently lists the volcano rabbit as an endangered species and, in 2019, estimated that roughly 7,000 rabbits remained in the wild, noting that the population was decreasing. Hunting, livestock grazing, and fires can harm R. diazi even within the boundaries of national parks; Conservation File:Taxidermied romerolagus diazi.JPG|thumb|right|A taxidermied female volcano rabbit born in Jersey Zoo in the mid-1980s the impact humans have on the volcano rabbit, and proposed remedial actions, but by 2018 no part of the plan had been implemented. Some populations have been able to recover due to volcanic activity at Popocatépetl, which has restricted incursions by herders and tourists. == References ==