Moby Big

Fact vs. legend

There is a lot of folklore around this strain. Here is which bits are real, side by side.

What we actually know

• Moby Big is a plain Psilocybe cubensis. The name refers to a hobbyist-bred line, not a separate species or a wild collection.
• It is reportedly a hybrid: the leucistic Moby Dick crossed with the well-known B+, then back-crossed and stabilised. That makes it a hybrid of a hybrid.
• Moby Dick, one of its reputed parents, is a leucistic line (itself said to descend from Albino A+ crossed with Golden Teacher), which is why Moby Big tends to lean pale and frosted in the cap.
• Because it is leucistic and not albino, the body loses pigment but the spores do not. It still drops a dark purplish-brown print, which is unusual for such a pale-looking mushroom.
• It is a relatively modern vendor name with very little documented, verifiable history. Most of what circulates traces back to the seller's own catalogue copy.

What the community says

• The line is widely attributed to MushMush, a Dutch spore vendor also linked to the early releases of White Rabbit and to Moby Dick itself. Treat the specific breeding claims as their own account rather than independently verified record.
• The standard story is that Moby Dick and B+ were crossed, back-crossed and stabilised to fix the look. That is a plausible hobbyist breeding path, but no public lab pedigree backs the exact steps.
• Some sellers bill it as a notably strong cube on the strength of its lineage. There is no reliable testing behind that ranking, and as the saying goes, a cube is a cube.
• The name is almost certainly a simple play on its parents: the Moby of Moby Dick plus the Big of a chunky fruitbody, or a nod to B+. Nobody has documented an official explanation, so the etymology is guesswork.
• Through Moby Dick and Albino A+, its family tree is sometimes traced back to the same anonymous Mr. G associated with B+ folklore. That is a fun bit of lineage gossip, not established fact.

A hybrid of a hybrid, with a paper trail that runs out fast

Moby Big is one of those names that sounds like it has a long pedigree and then, the moment you start pulling threads, turns out to be quite young and quite undocumented. By most accounts it is a modern release attributed to MushMush, a Dutch spore vendor better known for Moby Dick and for the early White Rabbit drops. The widely repeated story is that someone took the ghost-pale Moby Dick, crossed it with the dependable old B+, then back-crossed and stabilised the result until the look held true. It is a believable hobbyist breeding path, but almost everything written about it traces back to seller copy rather than any independent record.

What makes the lineage genuinely interesting is that Moby Big is a hybrid of a hybrid. Moby Dick is itself reportedly Albino A+ crossed with Golden Teacher, which is why it carries that frosted, low-pigment look. Stir in B+, the big easygoing classic, and you get a mushroom that leans pale and chunky at once. Follow the family tree far enough and, through Albino A+, you even bump into the same anonymous Mr. G who haunts B+ folklore, though that connection is gossip rather than gospel.

The version is that Moby Big is a recent vendor line with a thin paper trail. The breeding story is plausible and widely repeated, but it is the seller's account, not documented history.

Leucistic, not albino, and that matters in the lab

Here is the part collectors actually care about. Moby Dick, and the Moby Big that follows it, are leucistic rather than true albino. Leucistic means the fruitbody loses most of its pigment, going pale to faintly blue, while the spores keep their colour. So despite a body that can look bleached or frosted, Moby Big still drops a dark purplish-brown print, which is the opposite of what a true albino does. For anyone putting it under glass, that is good news: dark, well-pigmented spores are far easier to find and study than the faint, near-transparent spores an albino line tends to give up.

Meet Psilocybe cubensis

Moby Big is a collector's line of a single, well-travelled species. Psilocybe cubensis was first written up in 1906 by the American mycologist Franklin Sumner Earle, from a specimen found in a cattle field in Cuba, which is where the name comes from. He originally called it Stropharia cubensis; Rolf Singer moved it into the genus Psilocybe in 1948.

The genus name is a tidy bit of Greek: psilos ("bare") plus kubē ("head"), for the smooth, peelable skin of the cap, so the full name reads roughly as "the bare-headed mushroom from Cuba."

Family

Hymenogastraceae (older books say Strophariaceae)

Genus

Psilocybe (Fr.) P. Kumm., 1871

Species

Psilocybe cubensis (Earle) Singer, 1948

Basionym

Stropharia cubensis Earle, 1906

This product

Moby Big, a collector's cultivar of the species

Type locality

Cuba (where it was first named)

Field marks

These describe the mature mushroom for reference and identification.

Pale, frosted cap

Tends toward Moby Dick's reduced-pigment look: pale to faintly light-blue, often appearing frosted or bleached rather than golden. Conical when young, opening to convex or flat with age, and reportedly inclined to chunky, generous fruitbodies in line with the Big in the name.

Thick ivory stem

Stout, meaty and fibrous, ivory to white, in keeping with both reputed parents. A leftover partial veil usually leaves a ring-like annulus around the upper stipe that catches a dusting of falling spores.

Gills that darken to the print

Crowded and pale grey when young, deepening toward near-black as the spores ripen. The contrast against the pale cap is part of the leucistic look, and the maturing gills are what load the dark print this line still produces.

Blue bruising on the pale flesh

Like other cubensis, handled or damaged tissue bruises blue-green as an enzyme converts psilocybin to psilocin, which oxidises into blue pigments. On Moby Big's bleached flesh that bruising can read especially vivid against the pale background.

A dung-lover with a wanderer's history

Psilocybe cubensis is coprophilic, a fancy word for dung-loving. In the wild it lives on the droppings of big grazing animals, classically cattle and water buffalo, fruiting from warm, humid pasture. It does not grow on wood and it does not partner with tree roots.

You'll find it across the warm parts of the world: the Gulf Coast of the United States, Mexico, Central and South America, Southeast Asia and Australia. It was named from Cuba, but where the lineage truly began is an open question. A 2026 study describing its closest wild relative in southern Africa suggests the deep roots are Old-World, the mushroom having apparently travelled with grazing herds long before anyone gave it a Latin name.

Under the microscope

This is what you actually bought the spores for. Put a print or a drop from a syringe on a slide and here's what shows up.

• Shape & size. Smooth, thick-walled and subellipsoid, like a slightly squashed rugby ball, roughly 11.5–17 µm long by 8–11 µm wide (the figures Paul Stamets settled on).
• The germ pore. Look for a single pale, flattened dot at one end. That's the one thin spot in the wall where, in nature, a mushroom would begin, and a real cubensis hallmark.
• Pale alone, dark in a crowd. A single spore looks honey-amber with the light behind it; only in a mass do they read deep purple-brown to black. So a near-black print but pale spores on the slide is normal optics, not a dud.
• Expect a dark sample despite a pale mushroom. Moby Big is leucistic rather than albino, so the fruitbody loses pigment but the spores do not. Unlike a true albino line, which tends to drop faint or near-transparent spores that are hard to locate, this one deposits well-pigmented purple-brown spores that read clearly under the scope, so a methylene blue stain is optional rather than near-essential.
• What you'll need. Find the field at 100×, study shape and the germ pore at 400×, and get the wall crisp at 1000× under oil. A touch of methylene blue or KOH lifts the contrast.
• The legal bit, and why it's true. A dormant spore carries no psilocybin or psilocin at all; that chemistry only appears later in living tissue. That is exactly why the spores are legal to own and study in the UK.

Print, syringe, vial or swab?

Same lab-grade genetics in every option. The honest difference is shelf life versus how soon you're at the scope.

Spore print

Keeps longest

Spores dropped straight onto sterile foil. Stored cool and dry it outlasts everything else here, so it's the one to reach for if you're building a collection to keep for years.

Spore syringe

Ready tonight

Spores suspended in sterile water, ready to go straight onto a slide. The quickest way to be looking down the microscope this evening. Comes in 3 mL and 12 mL.

Vial & swab

Compact

A sealed glass vial is a tidy middle ground; a sterile swab is the most travel-friendly, robust little format for adding a strain to your reference set.

The spec sheet

Species

Psilocybe cubensis

Strain

Moby Big (collector's cultivar)

Spore print

Dark purple-brown to near-black, heavy depositor

Spore shape

Subellipsoid, smooth, thick-walled, with a germ pore

Spore size

~11.5–17 × 8–11 µm

Basidia

Mostly 4-spored, ~20–30 × 7–10 µm

Wild habitat

Coprophilic, on herbivore dung & warm pasture

Climate

Subtropical to tropical

Intended use

Microscopy, research & collecting only

Further reading

Independent, non-commercial sources, no shops, just good information.

• Psilocybe cubensis on Wikipedia: the species overview.
• The genus Psilocybe: taxonomy and the family reshuffle.
• Index Fungorum: the formal nomenclature record.
• Proc. Royal Society B (2026): the African wild-relative study.