CAENOPHIDIA 1
ADVANCED SNAKES
[page 2] [page 3]

The Infraorder Caenophidia contains all advanced snakes although the precise phylogenies within this complex infraorder are in continual flux as different authors propose different cladograms. The one applied here is not necessariy the correct one and certainly not the only one available. One thing that is certain is that the old simple arrangement of Acrochordidae (filesnakes), Elapidae (fixed fanged venomous snakes), Viperidae (hinge-fanged venomous snakes) and Colubridae (all other advanced snakes) is out-dated and inaccurate. The huge former 'dustbin taxa' Colubridae has been split into several families (former subfamilies in some cases) while the evolutionary tree Colubridae to Elapidae to Viperidae is without doubt an out-moded and unrealistic view of the evolutionary relationships of these higher taxa.

The Caenophidia, as currently recognised, contains eleven families, eight of which are represented in the photo library:

1. Acrochordidae

2. Xenodermatidae

3. Pareatidae

4. Viperidae

5. Homalopsidae

Elapoidea:
6. Elapidae; 7. Lamprophiidae

Colubroidea:
8. Colubridae; 9.Dipsadidae; 10.Natricidae; 11. Pseudoxenodontidae

Phylogeny of the Caenophidian Snakes (adapted from the diagram in O'Shea 2005 Venomous Snakes of the World) based on phylogenies by Vidal 2002, Fry & Wüster 2004, and adopting the latest phylogeny by Vidal et al 2007 (click on figure to enlarge and view references)

Legend:
Photographic locality. Wherever possible precidence is given to wild specimens from known localitions, wherein the 'photographic locality' relates to the origin of the photographed specimens, rather than the taxon's entire range. The only exceptions are indicated by (captive) or (preserved specimen). These are either specimens photographed in captivity, where the locality given is a general distribution for the taxon, or preserved specimens photographed as biological voucher specimens.

Column D1. Digitized images - the bulk of the library consists of 35mm transparencies (mostly Kodachrome or Velvia) which are gradually being digitized [using Nikon CoolScan 4000 or Plustek OpticFilm 7600i] and stored on hard disc. 'X' indicates that digitized images are available, '[]' indicates that the transparencies of this taxon have yet to be digitized.

Column D2. Digital images - since 2005 digital images have also been taken [using Canon EOS 30D, 40D or 7D]. 'X' indicates that digital images are available in addition to digitized images for this taxon.

ACROCHORDIDAE
FILESNAKES

The Acrochordidae is a unique Australo-Asian taxon which is sometimes omitted from the Caenophidia. It contains one genus and three species, all of which are present in the photo library.

Acrochordidae Filesnakes

LITTLE FILESNAKE Acrochordus granulatus Hey-Emblem estuary, Weipa, Queensland, Australia

click on image to enlarge

HOMALOPSIDAE
AUSTRALO-ASIAN MUD & MANGROVE SNAKES

The Homalopsidae was formerly a subfamily of the Colubridae but is now considered a distinctly separate famil. It contains forty species, in twelve genera, of mildly venomous rear-fanged and nonvenomous freshwater and estuarine, mud and mangrove snakes from Australo-Asian Archipelago. The photo library contains seven species from six genera.

Homalopsidae Mud & mangrove snakes

RICHARDSON'S MANGROVE SNAKE Myron richardsonii Sigabaduru, Western Prov., Papua New Guinea

click on image to enlarge

ELAPOIDEA
(for Elapidae click here)

A recent phylogeny of the Colubroidea (Vidal et al 2002) removes the Xendermatidae, Pareatidae and Homalopsidae from the Colubridae and splits the remaining families between the superfamily Colubroidea (Colubridae, Natricidae, Pseudoxenodontidae and Dipsadidae) and the superfamily Elapoidea (Elapidae, and the Lampropeltiidae, the latter formerly a subfamily of the Colubridae). The suggestion is that the Lamprophiidae is closer to the Elapidae than to the Colubridae etc. This raises interesting questions about venom delivery mechanisms in these snakes.

LAMPROPHIIDAE
SANDSNAKES, HOUSESNAKES & STILETTO SNAKES

The Lamprophiidae is primarily an African-Malagasy family, although some species range into southern Europe, the Middle East and Asia. It contains four subfamilies (Atractaspidinae; Lamprophiinae, Psammophiinae and Pseudoxyrhophiinae) all of which are represented in the photo library by three genera and six species; six genera and 14 species; four genera and eleven species (12 taxa), and three genera and five species, respectively. One monotypic species genus is incertae sedis.

	Atractaspidinae Stiletto snakes and their allies
	CORPULENT STILETTO SNAKE Atractaspis corpulenta corpulenta Korup National Park, Southwestern Prov., Cameroon
Lamprophiinae Housesnakes and their allies	Psammophiinae Sandsnakes and their allies	Pseudoxyrhophiinae Malagasy snakes
LAKE TANGANYIKA WATERSNAKE Lycodonomorphus bicolor Isanga Bay, Lake Tanganyika, Zambia	EASTERN BARK SNAKE Hemirhagerrhis nototaenia Chitili, Lake Tanganyika, Zambia	GIANT MADAGASCAN HOGNOSE SNAKE Leioheterodon madagascariensis Madagascar
click on images to enlarge

COLUBRIODEA

The Colubroidea retains four families, three of which are represented in the photo library, only the Asian Pseudoxenodontidae being absent.

COLUBRIDAE
TYPICAL SNAKES

Despite the splitting of the Colubridae resulting in the removal of large numbers of taxa to other families, this family remains one of the largest in the Serpentes. The Vidal et al (2002) revision recognises three subfamilies, two of which are represented in the photo library (the Grayiinae from Africa is absent). The Calamariinae is Asian and represented by a single species, while the Colubrinae is virtually worldwide in distribution and represented by 156 species (177 taxa) from 67 genera.

Calamariinae Reed snakes	Colubrinae Typical snakes
VARIABLE REED SNAKE Calamaria lumbricoidea Ulu Ulu, Temburong, Brunei	COMMON PARADISE FLYING SNAKE Chrysopelea paradisi paradisi Rakata Is., Krakatau Is., Indonesia
click on images to enlarge

NORTHERN RUFOUS EGG-EATING SNAKE Dasypeltis medici medici S.Africa	RHINOCEROS RATSNAKE Rhynchophis boulengeri Vietnam	BLANDING'S TREESNAKE Toxicodryas blandingi Tropical Africa
click on images to enlarge

DIPSADIDAE
AMERICAN ODD-TOOTHED SNAKES

A major family removed from the Colubridae is the New World Dipsadidae (at one time known as the Xenodontidae), the odd-toothed snakes. This family is divided into three subfamilies depending on the origin of the genus concerned and its phyogenetic relationships, ie. North America (Heterodontinae), Central America (Dipsadinae) or South America (Xenodontinae). The photo library represents these subfamilies as two genera with four species (five taxa); ten genera and 16 species, and 14 genera with 26 species (30 taxa) respectively.

Dipsadinae Central American odd-toothed snakes	Heterodontinae North American odd-toothed snakes	Xenodontinae South American odd-toothed snakes
BROWN BLUNT-HEADED TREESNAKE Imantodes inornatus Liverpool, Rio Blanco, Costa Rica	PLAINS HOGNOSE SNAKE Heterodon nasicus nasicus USA	AMAZONIAN FALSE CORALSNAKE Erythrolamprus aesculapii aesculapii Ilha Maraca, Roraima, Brazil
click on images to enlarge

NATRICIDAE
KEELBACKS & WATERSNAKES

The keelbacks or freshwater watersnakes of the Natricidae are a natural group although not all watersnakes belong to the Natricidae, ie Homalopidae of Austral0-Asia, Grayia of Africa, Helicops of S.America, and not all members are aquatic. The photo library contains 13 genera and 35 species (44 taxa).

Natricidae Keelbacks & watersnakes

LONG-TAILED COMMON KEELBACK Tropidonophis multiscutallatus Girigarande, Western Prov., Papua New Guinea

click on image to enlarge