The Corallus hortulanus - complex:

The revision of this complex is a bit older than some of the other revisions we have described, but we feel that it has quite some relevance, while a lot of Tree Boas still are treated as Corallus enydris or Corallus hortulanus without differentiating between the seperat species.

In 1996 (McDiarmid et al.) the species known by many as Corallus enydris (Linnaeus, 1758) was determined again to be a junior synonym of Corallus hortulanus (Linnaeus, 1758). The two species was described as Boa Enydris and Boa Hortulana in the 10th edition of Systema Naturae on respectively page 215 and 215-216. As the original describtion of both species was quit similar and without any significant differences to tell the species apart, the first revision of the species as Corallus hortulanus with Corallus enydris as a synonym by Duméril and Bibron in 1844 is to be used as the designation of the senior synonym.

The species Corallus hortulanus (or Corallus enydris as it was mainly called) was generally split into the two subspecies hortulanus (or enydris) and cookii.

Then in 1997 the major worker on this complex without a doubt, Robert W. Henderson, who has worked with these species for nearly to decades, published a taxonomic review of the hortulanus Complex, based on analyses of morphological characters and mtDNA (Henderson & Hedges, 1995) from over 600 specimens from the entire range of the complex. The result of this review was that the complex had to be split into the four species Corallus hortulanus (Linnaeus, 1758) , cooki Gray, 1842, grenadensis (Barbour, 1914) and ruschenbergerii.(Cope, 1876).

The data usefull for separating the species are seen in the following scheme based on data taken directly from Henderson (1997):

Morphology/species
hortulanus
cooki
grenadensis
ruschenbergerii
Dorsal scale rows
47-63
39-48
37-46
38-48
Ventrals
258-297
257-278
257-278
250-272
Subcaudals
105-137
100-122
100-119
94-115
Scales between supraoculars
5-14
7-13
3-9
3-10
Infraloreals
0-9
0-4
0-4
0-6
Circumorbital scales
8-17
10-14
8-14
11-16
Dorsal ground color
Variable (yellow, gray, taupe, brown, pind, or reddish)
Always taupe, groay, or brown
Variable (yellowish, orange, gray, taupe, brown)
Yellow brown to deep copper brown
Distribution Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname and Venezuela St. Vincent Baliceaux, Bequia, Canouan, Carriacou, Grenada, Ile Quatre, Mayreau, Mustique, Petit Martinique and Uniion Island Colombia, Costa Rica, Panama, Tobago, Trinidad, Venezuela

This new taxonomy of course gives some problems for hobbyists and scientists used to the old definition of the complex as a species with two subspecies. The old taxonomy for the complex had the nominatform living in the same area as is now the case for Corallus hortulanus. The subspecies cooki on the other hand has with this new taxonomy been split into three seperat species, which is the cause of confussion. What we used to call Corallus enydris cooki or C. hortulanus cooki could now be three different species. And probably the all belong to the nominat species, as both cooki and grenadensis has rather limited distributions and most of the contries in the range of C. ruschenbergeri are no large exporters of wildlife.

Literature:

  • Henderson, R.W. 1997. A Taxonomic Review of the Corallus hortulanus Complex of Neotropical Tree Boas. Carib. J. Sci., 33(3/4): 198-221.
  • Henderson, R.W. & S.B. Hedges. 1995. Origin of West Indian Populations of the Geographically Widespread Boa Corallus enydris Inferred from Mitochondrial DNA Sequences. Molec. Phylogen. Evol., 4: 88-92.
  • McDiarmid, R.W., T. Touré & J.M. Savage. 1996. The Proper Name of the Neotropical Tree Boa Often Referred to as Corallus enydris (Serpentes: Boidae). J. Herpetol., 30(3): 320-326.