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Dark Locus: Black Phenotypes
The allele that is responsible for the black coloration in black phenotypes is referred to as the “dark” allele and is designated with the symbol D. 

Possible black phenotypes are:
Double Dark Black (D/D)
Hybrid Black (D/g, D/Gm, D/M)
Black Lace (D/+)

Black dd

 Black (D) exhibits co-dominance with the wild type allele (+).  It is dominant to marble (M), gold marble (Gm), and gold (g) alleles.

Three distinct phenotypes of black occur: black, hybrid black and black lace.  Black angelfish are homozygous for the dark allele (D/D) and are commonly called “double dark” blacks.  Hybrid blacks have one allele for dark and one for marble, gold marble or gold.  Black lace angelfish contain one dark allele and one wild-type allele.  The table below summarizes how the allele for dark interacts with other alleles at this locus to form the black phenotypes. 



Double Dark Black

Hybrid Black

Black Lace



D/M, D/Gm, or D/g


Pattern of inheritance:


Dark is dominant to  Marble, Gold Marble, and Gold 

Dark is co-dominant with wild type (blending of traits)

Factors that Affect Expression of the Black Phenotype
The dark allele is constant in its expression, meaning that if it is present in the genotype, it will always express in the phenotype (except in an albino).

Changes in the Phenotype as the Angelfish Matures
In both double dark blacks and hybrid blacks, the black coloration is initially a light gray in the fry and young juveniles, allowing underlying striping to show through clearly.  The dark color deepens as they mature, masking the stripes under normal lighting.

Double Dark Black
A double dark black is homozygous for the dark allele, with the genotype D/D.  A good quality double dark black will be nearly carbon black, and stripes will not be visible.  However, if a photo is taken with a flash, or if a flashlight is shined directly at the fish, underlying stripes can be seen.  As it matures, it often develops a blue hue in the gill area.

Black dd
This photo of a double dark black was taken with a flash, which reveals the underlying stripes.


A double dark black generally grows more slowly than a hybrid black or a black lace, although more vigorous strains are being raised today as a result of good breeding programs.   

Hybrid Black
Hybrid black angelfish have one dark allele paired with a marble (D/M), gold marble (D/Gm), or gold allele (D/g).  The most popular choice for a hybrid black is to pair the dark allele with gold.  This results in a deep creamy black color. With hybrid black angelfish, an underlying pattern can be seen under a bright light or in a photograph taken with a flash.  The genotype D/g will have underlying darker stripes, whereas the genotypes D/M and D/Gm will have underlying darker marbling. A hybrid black will generally grow faster than a double dark black.  A good quality hybrid black will be nearly as dark as a double dark. 

Hybrid Black

Black Lace
The black lace is an attractive phenotype that is formed by combining one dark allele with one wild allele: D/+.  The dark and wild alleles are co-dominant, resulting in a blending of the two traits. This results in coloration in which the body is somewhat darkened to a light charcoal color, but not a deep black.  The wild type stripes show clearly.  The tail and fins have a lacy pattern.  The stripes will fade or darken with the mood of a black lace, as in a silver angelfish.  The overall charcoal coloration of the body, however, will remain constant.       

Photo: Black Lace – The body is darker than the wild type silver angelfish, but lighter than a black angelfish.  The black stripes of the wild type are clearly seen.  The tail and fins have a lace pattern.


 Gene Interactions
Many popular and attractive phenotypes are formed when black phenotypes are combined with non-wild alleles for other genes.

Interactions with the Zebra/Stripeless Locus
The table below shows phenotypes that result when black phenotypes are combined with alleles at the zebra/stripeless locus.  A zebra lace, for example, results when one or two zebra alleles are added to the genotype for a black lace. 

Phenotypes resulting from Black + Zebra (Z) and/or Stripeless (S)




D/M, D/Gm, D/g

Z/+, Z/Z

Zebra Lace
Zebra Lace

Zebra Black



Black Ghost

Black Ghost
Black Ghost

Hybrid Black Ghost



Turquoise BlushingTurquoise Blushing

Black Blushing (velvet)
Black Blushing

Hybrid Black Blushing (velvet)


Clown Black

Black Clown

Hybrid Black Clown

Interactions with the Smokey Locus
This next table shows phenotypes that result when black phenotypes are combined with alleles from the smokey locus. 

Phenotypes resulting from Black + Smokey (Sm)




D/M, D/Gm, D/g


Smokey Lace

Smokey Black

Smokey Hybrid Black


Chocolate Lace

Chocolate Black

Chocolate Hybrid Black

Interactions with the Albino Locus or Halfblack Locus
The albino trait is recessive, so it will only express when present in the homozygous form (a/a).  Albino will suppress the development of dark pigment, resulting in an albino angelfish.

Halfblack is also a recessive trait that will only express when present in homozygous form (h/h).  The halfblack trait will be visible when added to the black lace phenotype.  However the black and hybrid black phenotypes are already black colored, so even if the halfblack trait expresses, it won’t be discernable against the black pigment from the dark allele.  

Phenotypes resulting from Black + Albino (a) or Halfblack (h)




D/M, D/Gm, D/g


Albino Black Lace

Albino Black

Albino Hybrid Black


Black Lace Halfblack

Black Halfblack

Hybrid Black Halfblack


Interactions with the Streaked Locus, Pearlscale Locus, or Veil Locus
When alleles from the streaked locus, pearlscale locus, or veil locus are added to a black phenotype the color the black phenotype is not altered.  Instead, the non-wild alleles at each of these loci adds an additional effect. 

The streaked allele is dominant, so one or two streaked alleles (St/+ or St/St) will result in addition of a white stripe to the body, dorsal fin and anal fin.

Pearlscale is a recessive trait, so will only express when present in the homozygous form (p/p).  Even in homozygous form, the pearlscale trait does not always express.  If it does express, the reflective characteristic of the scales doesn’t show up very well against the black coloration.  Pearlscale will be more apparent in the black lace phenotype than in a black or hybrid black. 

Veil tail is a partially dominant trait that will result in lengthening and broadening the tail, and in lengthening the dorsal and anal fins when present in heterozygously (V/+) to produce a veil tail angelfish.  When present homozygously, the tail and fins are further lengthened to produce a super veil tail.

Phenotypes resulting from Black + pearlscale or veil




D/M, D/Gm, D/g

St/+, St/St

Streaked Black Lace

Streaked Black

Streaked Hybrid Black


Black Lace Pearlscale

Black PearlscaleBlack Pearl Scale

Hybrid Black Pearlscale


Black Lace Veil Tail

Black Veil Tail

Hybrid Black Veil Tail


Black Lace Super Veil Tail

Black Super Veil Tail

Hybrid Black Super Veil Tail

 Links to more information about black phenotypes
Dr. Joanne Norton, FAMA: July 1984; Vol. 7, #7
Dr. Joanne Norton, FAMA: May 1989, Vol.12, #5

Approved by The Angelfish Society Standards Committee on February 11, 2007.