ALBI Albino Recessive amelanistic mutation. T- (tyrosinase-negative): tyrosinase enzyme activity is eliminated; eumelanin (black) pigment cannot be synthesized. Phaeomelanin and other pigments are unaffected, producing the characteristic yellow-and-white-with-red-saddles phenotype. Pink eyes due to absence of eumelanin in the iris. Recessive Line-specific ›
ANAC Anaconda Pattern reduction gene with dosage-dependent expression. This locus is correctly classified as incomplete dominant (often called "co-dominant" in the hobby — see note below): heterozygous and homozygous animals look visually distinct.
Heterozygous Anaconda (one copy): Significantly reduced and broken dorsal pattern. The typical bold saddle marks of wild-type are replaced by reduced, irregular, or fragmented patterning. The pattern often appears as broken bands, reduced spots, or heavily faded saddles along the dorsum. The lateral and ventral patterns are similarly reduced. Some Anaconda hets retain more pattern than others (variable expressivity), but the reduction is consistent and diagnostic.
Homozygous Anaconda / Super Anaconda (two copies): Dramatically reduced pattern approaching near-patternless. Dorsal is largely uniform in color with minimal to absent saddle marks. Most Super Anacondas appear nearly solid in color, with only faint ghosted pattern or scattered small markings. This is one of the most visually dramatic expressions of any hognose mutation.
HOBBY TERMINOLOGY NOTE: This locus is called "co-dominant" by most western hognose breeders, using the hobby convention where any mutation with a visually distinct het is labeled "co-dominant." The correct genetic term for a mutation where het and super are distinct (dosage effect) is "incomplete dominant." This file uses the correct terminology. Breeder-facing UI may wish to display "co-dominant (Anaconda / Super Anaconda)" as the label.
No health defects (neurological or developmental) have been documented for Super Anaconda in western hognose snakes. Co-dominant Common ›
AXAN Axanthic Reduces or eliminates xanthophore pigment (yellow and red pigment). Homozygous Axanthic animals display a silvery-gray to blue-gray coloration with reduced or absent yellow and orange tones. The typical warm orange-brown of wild-type is replaced by cool gray tones. Dark pattern elements (saddle marks) are retained but appear in contrasting dark gray to black against the silvery base.
Melanin is fully retained — eyes remain dark, and the animal can appear quite striking in its silver-gray and black patterning. Axanthic is independent from Lavender (the two produce distinct phenotypes and complementation crosses produce wild-type-appearing double hets).
When combined with Albino, produces the Snow morph — the absence of both melanin and xanthophores results in a near-white animal. Line-specific ›
CARA Caramel Shifts overall pigmentation toward warm brown and caramel tones. Homozygous Caramel animals display a warm golden-brown to caramel background color with brown saddle marks. The typical orange-brown of wild-type shifts to a warmer, more uniform brown-caramel tone with reduction of contrasting dark pigment elements. Melanin is retained but appears in warmer brown rather than dark gray-black tones.
Caramel is a distinct locus from Albino, Axanthic, and Evans Hypo. The mutation appears to affect the balance of eumelanin and phaeomelanin, shifting pigmentation toward brown/yellow-brown rather than removing pigment classes entirely.
Participates in combo morphs including Lemon Ghost (Caramel + Evans Hypo; exact genetic basis may vary by breeding line) and various Anaconda combos. Line-specific ›
EVHY Evans Hypo Reduces melanin production (hypomelanistic). Homozygous Evans Hypo animals display a general lightening and brightening of coloration — darker pigment elements are reduced in intensity, producing a cleaner, higher-contrast appearance with brighter orange and yellow tones and lighter, less dark-edged saddle marks. Unlike Albino, Evans Hypo does not eliminate melanin; it reduces it, so eyes remain dark and some dark pigment persists in patterning.
The "Evans" designation distinguishes this hypomelanistic line from other hypo lines that have been claimed in western hognose. Named after Randy Evans, who established and documented the original line. Community complementation testing confirms this line is genetically distinct from any other hypo lines produced by different breeders (Hypo A x Hypo B = wild-type-looking double hets when from different lines, confirming independent loci).
When combined with Albino, produces the Coral morph — a vivid orange-coral animal where Evans Hypo's melanin reduction works synergistically with complete albinism to produce intense warm coloration. Line-specific ›
LAV Lavender Produces distinctive grey-lavender coloration. Homozygous Lavender animals display a soft gray background with lavender, lilac, or purple-gray undertones. The warm orange tones of wild-type are reduced and shifted toward cool lavender and gray. Saddle marks typically appear as darker lavender to brownish-purple against the lighter lavender base.
Lavender is independent from Axanthic: the two mutations produce visually distinct phenotypes (Lavender has a warmer purple-gray vs. Axanthic's cooler silver-gray), and complementation testing confirms they are at different loci. Some older sources erroneously conflate Lavender with Axanthic; they are distinct mutations.
Lavender participates in combo morphs including Arctic (Axanthic + Lavender, producing an icy pale animal) and various Anaconda combos. Line-specific ›
TOFB Toffee Belly Modifies belly coloration and patterning. Homozygous Toffee Belly animals display a distinctive yellow-toffee or golden-amber coloration on the ventral surface, replacing the typical black-and-white checkered belly pattern of wild-type western hognose snakes. The dorsal pattern may also show some modification, typically appearing slightly lighter or with modified contrast.
The belly modification is the primary and most diagnostic feature of this mutation. The toffee/golden-amber belly color creates a striking visual contrast with the dorsal pattern and is immediately recognizable in visual animals. Toffee Belly is independent from all other listed loci.
Creates the Toffeeconda combo when combined with Anaconda, where the modified belly coloration meets the reduced dorsal pattern. Line-specific ›
• Albino Homozygous Albino. Removes all melanin. Bright yellow-orange background with white or cream saddle marks and red/pink eyes. No dark pigment anywhere on the body. The most common western hognose morph and the foundation of the morph market. Common ›
• Anaconda Heterozygous Anaconda. Significantly reduced and broken dorsal saddle pattern. Typical bold hognose saddle marks are replaced by reduced, irregular, or fragmented patterning. Lateral pattern similarly reduced. Variable expressivity — some individuals show more reduction than others — but the broken/reduced dorsal pattern is consistently diagnostic. Called "co-dominant" in the hobby; correctly classified as incomplete dominant. Co-dominant Common ›
• Axanthic Homozygous Axanthic. Removes yellow and red pigment; melanin fully retained. Silvery-gray to blue-gray background with bold dark gray to black saddle marks. Cool-toned, striking silver and black coloration. Dark eyes. Line-specific ›
• Caramel Homozygous Caramel. Shifts coloration to warm golden-brown and caramel tones. Background becomes a warm toffee-brown; saddle marks appear warm brown rather than dark gray-black. Overall warm, earthy coloration. Dark eyes. Line-specific ›
• Evans Hypo Homozygous Evans Hypo. Reduces melanin production without eliminating it. Produces a brighter, cleaner animal with reduced dark pattern elements, lighter-edged saddle marks, and more vivid orange and yellow tones. Dark eyes are retained (distinguishing it from Albino). Named after Randy Evans who established the line. Line-specific ›
