Puerto Rican boa

It is extremely similar to the Jamaican boa (Chilabothrus subflavus) which was seen as conspecific for some fifty years until they were split in 1901 by Leonhard Hess Stejneger.[6]

The taxon Piesigaster boettgeri was described from Mindanao in the Philippines, by the Spaniard es:Víctor López Seoane in 1881, but was identified as a synonym of this species by Stejneger. Seoane's brother was an officer in the Spanish Navy and thus the localities of the group of specimens Seoane had obtained were confused during their passage to Spain.[6]

Although it has been known under the name E. inornatus for over a century, having been moved to the genus Epicrates (which had been created in 1830 by Johann Georg Wagler) by the Belgian zoologist George Albert Boulenger in 1893 when cataloguing the specimens in the Natural History Museum, London, a number of authors decided to it move to Chilabothrus inornatus in 2013. It had first been moved to Chilabothrus inornatus from the genus Boa in 1844 by either the French herpetologists André Marie Constant Duméril and Gabriel Bibron,[4] or the Italian snake expert Giorgio Jan,[6] only a year after it had been described in that genus by the Dane Johannes Theodor Reinhardt in 1843. Reinhardt had three snakes of this species to study for his description, these are the syntypes and are stored in Copenhagen. They were collected by a certain Dr. Ravn from Puerto Rico.[4][7] It is often still known as Epicrates inornatus in many publications.

A characteristic of the species is the irregular parietal scales. It can grow to some 1.9 m (6.2 ft), with 261 to 271 ventral scales and 67 to 75 caudal scales, according to Stejneger in 1904, who only knew of at least twelve specimens at the time. The colours of the three live specimens he knew of were variable; two he describes as "bistre" (deep, dark, grayish brown), the other as "chestnut" with a darker colour near the tail, the first had a darker ventral surface, the second he describes as "slate" coloured, and the last had a lighter slate-brown underside with the ventral scales having paler edges. The first was patterned with seventy to eighty indistinct dusky cross bars consisting of a row of spots, these cross bars increasing in width to the end of the snake; in the second these patterns were much more distinct, with the crossbars having pale centres but being outlined in blackish colour, the lateral spots being so aligned as to form a blackish line in the front third of its body, but in the last snake there was little evidence of patterning with only a few scattered and obscure darkish spots on its sides. The iris he describes as "silvery gray clouded with dusky".[6]

It grows to 1.8–2.7 m (5.9–8.9 ft) in total length.

The Puerto Rican boa is endemic to Puerto Rico.[1][4][8]

Historic records, some dating back to the 18th century, indicate that during the first few centuries of Spanish colonization in Puerto Rico the boa was relatively abundant, and oil produced from the snake's fat was utilized extensively as an export (see snake oil). Impacts to the boa resulting from the oil trade were undoubtedly heightened by a concurrent reduction of habitat. Deforestation of the island began during this period and continued until, by the early 20th century, very little natural forest remained. Predation by the mongoose, introduced into Puerto Rico in the 19th century, has been postulated as a further cause for the boa's present status, but there is no direct evidence to support this idea.

In 1904 Stejneger mentions that during his time the snake was rather rare, he himself, as well as a number of other collecting parties in the newly acquired territory, were unable to see one during their expeditions on the island, although a trail of one was seen. Other collecting parties were able to collect five specimens in 1900 and in those first few years the island became a possession of the United States, and bring these to the mainland, almost doubling the specimens known at the time. In the previous century only six other specimens had been secured, these were all in Europe -one in Milan (used by Jan), one in Paris (studied by Duméril and Bibron from Bayamón, there was also a second specimen from Haiti, but this one is now thought to have been misidentified), two or more somewhere in Spain (those of Seoane supposedly from Mindanao), and the three original syntypes used by Reinhardt in Copenhagen.[6]

After the invasion and annexation of the territory by the United States a few years before Stejneger and numerous other Americans were able to collect on the island, there was a subsequent economic decline due of the loss of traditional agricultural markets for sugar, and much of the forests have regrown on the island. There is an indication that the boa has recovered somewhat in recent years, although not to the degree that protective measures can be dropped. To prevent its extinction, a few conservation efforts have been attempted, including a conservation area for it in San Patricio State Forest in Puerto Rico.

• List of reptiles of Puerto Rico
• Fauna of Puerto Rico
• List of endemic fauna of Puerto Rico

• Reinhardt JT. 1843. "Beskrivelse af Nogle nye Slangearter ". Danske Vidensk. Selsk. Afhandl. 10: 233–279. (Boa inornata, pp. 253–257, plate i, figures 21–23)