GUPPYPEDIA / DIRECT CROSS EVIDENCE
Seven specific reported crosses: five firsthand breeding reports and two controlled genetics studies. Original source-labeled diagrams illustrate those claims, not inventor status or universal commercial pedigree.
1988 · Diana Walstad
Observed: F1 were described as combining the male's brighter blue coloration with the female's improved finnage; subsequent colony breeding did not isolate a single formally tested genetic mechanism.
Evidence scope: Not documentation of the worldwide creator or origin of Blue Delta.
Original source (PDF page 1, Fig. 1)
Related existing catalog labels: GUP-030
2017 · Diana Walstad
Observed: F1 males combined their sire's iridescent blue body with their dam's grass/delta tail and large dorsal. Subsequent sibling F1 matings yielded both double-sword and delta-tail F2 males.
Evidence scope: Not proof that all commercial Japan Blue uses exactly the same Y-associated Ca allele or offspring ratios.
Original source (PDF pages 6–7, Figs. 10–13)
2017 onwards · Diana Walstad
Observed: After selected F1 males were backcrossed to Blue Grass females, 4 batches from one mating yielded Blue Grass, Red Grass and multicolor Christmas-pattern males. A separate sibling mating yielded a yellow snakeskin phenotype.
Evidence scope: Not a universal strain pedigree or guaranteed distribution; the follow-up includes distinct backcross and sibling matings.
Original source (PDF pages 8–9, Figs. 14–20)
Related existing catalog labels: GUP-032 | GUP-033 | GUP-022
2017 onwards · Diana Walstad
Observed: F1 included two snakeskin-patterned males; an F1 sibling mating produced F2 males without the father's desired snakeskin body-and-tail pattern in the breeder's observed batch.
Evidence scope: Not evidence that any named commercial Snakeskin line was invented by this cross.
Original source (PDF pages 5–6, Figs. 8–9)
2016 account · Igor Dusanic / Tropical Basement
Observed: After three generations of inbreeding within both lines, the author reports crossing a Line 1 male with a Line 2 female, yielding blue, dark blue, black, purple, green and dark green phenotypes. Selected purple males were crossed back to Line 1 females and selected green males to Line 2 females. The Line 1 account separately reports a 2010 Hawaiian Moscow x Shubel Full Blue Delta origin and 2015 return cross.
Evidence scope: Not a controlled Mendelian genotype test, independently verified F1 count, creator certification for Moscow generally, or current availability. This is an author-reported breeding program, with no licensed fish photos reused.
Original source (Dusanic, Tropical Basement, 13 September 2016, introduction and cross program)
Related existing catalog labels: GUP-071
1989 · V. P. E. Phang, L. N. Ng and A. A. Fernando
Observed: Controlled reciprocal single-pair crosses found dominant wild-type B versus recessive blond bb backgrounds. The studied male snakeskin body and tail patterns involved closely Y-linked factors Ssb and Sst; the green-yellow tail factor Grt was X-linked.
Evidence scope: Not a molecular genotype verification of every guppy sold as Snakeskin or Cobra; original investigators described possible X–Y recombination.
Original source (Journal of Heredity 80(5), 393–399, PubMed abstract)
Related existing catalog labels: GUP-022
1991 · V. P. E. Phang and A. A. Fernando
Observed: F2 segregation from reciprocal single-pair crosses supported non-allelic dominant X-linked tail-color factors Grt (green) and Blt (blue), with an average estimated distance of 19.4 map units.
Evidence scope: Not a universal X-linked classification of all blue or green guppies, nor measured physical genomic distance for retail stocks.
Original source (Zoological Science 8(5), 975–981, official abstract)
Related existing catalog labels: GUP-022
No matching crosses.
Parent lines not documented for generic commercial stock. Solid lines here depict only the explicit matings in the linked publication or firsthand account. They are not authenticated parent IDs or breed-origin genealogies for Moscow, Grass, Snakeskin, Japan Blue, Full Red or Koi at large. Stock-level genotypes, current breeder offers and photo permissions remain unresolved. First-person hobbyist claims and controlled studies are labeled as different evidence classes; no copyrighted fish photos are reproduced.