Mirror Carp

By Alex Clayton · Updated 23 October 2026

The heaviest carp on the ratified British record list is a mirror, at 68lb 1oz (30.875kg). Yet a mirror carp is not a separate species. It is Cyprinus carpio, the same fish as the common, leather and ghost carp, carrying a scale mutation that leaves large, irregular, reflective scales scattered over otherwise bare skin.

This guide covers how to tell a mirror from its relatives, what linear and fully scaled mirrors are, how big they grow, the rules that apply and how to handle a big one. For the wider family, see our guide to UK carp species.

What Is a Mirror Carp?

A mirror carp is not a hybrid and not a species of its own. It is a common carp, Cyprinus carpio, with a different scale pattern.

Biologists treat mirror, scaled, linear and leather carp as scale types of one species, controlled by a small number of genes (Casas et al., PLoS One, 2013). If a fish is a carp and carries big, uneven plates of scale with bare skin between, it is a mirror, whatever its size or colour.

The name comes from those plates, which are large and shiny enough to catch the light along the flank. The form came out of continental fish-pond culture. Carp were domesticated across Europe and spread by monastic fish farming between roughly the 13th and 16th centuries, and the mirror type is usually traced to German farm stock.

Carp are not native to Britain, and nobody knows exactly when they arrived. The Fishing Museum concludes the 14th century is most likely, tied to the medieval fashion for stew ponds, while older accounts give dates from 1496 to 1614. There is no good evidence for the popular story of a Roman introduction.

Most mirrors in UK lakes today are there because a fishery or club stocked them. Telling one from a common carp on the bank comes next.

Mirror Carp vs Common Carp (and Leather and Ghost): How to Tell Them Apart

One look along the flank tells you which carp you have. Check how much of the body is scaled and how even the scales are.

Variety	Scales	Other clues
Common	Full, even covering of uniform scales in neat rows	Bronze to olive, the “wild” look
Mirror	Large, irregular scales in patches, often along the back and near the lateral line, bare skin between	Scale pattern differs on each fish
Linear mirror	One continuous row of scales along the lateral line, sometimes a second along the back	Covered in the next section
Leather	Nearly bare, but usually keeps a few scales near the back or tail	Anal fin typically 3 to 4 rays, against 5 to 6 in mirrors
Ghost	Can be fully scaled or mirror-patterned	Metallic white, silver or gold sheen from koi crossing

Body shape is a weak clue. Mirrors are often described as fuller and rounder than commons, but shape varies so much between waters and stock that it misleads as often as it helps.

The hard call is a sparsely scaled mirror against a leather carp. Count the rays on the anal fin, the fin on the underside just in front of the tail. Simon Scott, writing in CARPology, gives 3 to 4 rays as typical for leathers and 5 to 6 for mirrors. That makes the count a strong guide, not a guarantee.

Ghost carp are a colour question rather than a scale one, so a ghost can also be a mirror. For crucians, bream and other fish that get mistaken for carp, use our freshwater fish identification guide.

For mirror carp vs common carp: even scales everywhere means common, uneven patches with bare skin means mirror.

Mirror Carp Scale Patterns: Scattered, Linear and Fully Scaled

“Fully scaled mirror” sounds like a contradiction, and in one sense it is. Anglers use three main labels for mirror carp patterns, and each means something specific.

Scattered (classic) mirror

This is the default mirror carp: irregular scales of different sizes dotted over the body, often clustered along the back, around the tail root and near the lateral line. Scientists call it the “scattered” class. No two look quite the same.

Linear carp

A linear carp has one continuous, unbroken row of scales running along the lateral line, from behind the gill plate to the tail. Some fish also carry a neat row along the back. The rest of the flank is bare. Many carp anglers rate a clean linear among the most attractive fish they can catch.

Fully scaled mirror carp

A fully scaled mirror carp is angler shorthand for a fish covered in scales, but scales of mixed, irregular sizes rather than the neat uniform rows of a common. In the genetic model covered below, a fully scaled body is the wild type, which is the common carp. So the label describes irregular scale size, not a separate mirror genotype. A fish like this sits between the two, and anglers argue about what to call it.

Whatever the pattern, it stays essentially the same through the fish’s life. That is why well-known big mirrors are recognised and given names, and why the pattern works almost like a fingerprint for an individual fish.

If you want to know whether you have caught a fish before, photograph the same flank every time.

Why Mirrors Look Like That: Scale Genetics in Brief

A mirror carp’s scale pattern largely comes down to two genes, and one combination of them is thought to be lethal. The classic model, set out by Kirpichnikov, uses two loci, S and N.

Pattern	Kirpichnikov genotype
Scaled (common)	SS/nn or Ss/nn
Linear	SS/Nn or Ss/Nn
Scattered mirror	ss/nn
Leather (nude)	ss/Nn
Any NN fish	Thought to be lethal

Treat this as a simplified model, not settled fact. Casas et al. (PLoS One, 2013) re-tested it on Hungarian stocks and found they did not show the expected lethality. They also showed that the “scattered” class contains classical mirrors plus several irregular sub-types.

The table does settle one thing anglers ask about. A leather is a genotype, not simply a mirror that has lost its scales. According to Simon Scott in CARPology, leathers tend to have fewer pharyngeal teeth and fewer white blood cells than commons, regrow only about 20 per cent of a damaged fin where a common regrows it fully, and survive less well in low oxygen. Those trade-offs help explain why leathers are scarcer than mirrors.

How Big Do Mirror Carp Grow? The British Record and Specimen Weights

Search for the British record mirror carp and you will find several different weights. Only one of them is on the official list.

The British Record (rod caught) Fish Committee coarse list, dated 30 January 2026, shows the carp record at 68lb 1oz (30.875kg). It is a mirror, caught by Dean Fletcher from Cranwell’s Lake on the Wasing Estate, Berkshire, in 2016 (BRFC coarse listings, Angling Trust).

Heavier mirrors do get reported. A 75lb 2oz (34.08kg) mirror from Holme Fen, caught by Wayne Mansford in October 2020, was reported at the time as yet to be verified by the BRFC. The 2026 list still shows 68lb 1oz, so it is not the ratified record. A fish only becomes the British record when the committee ratifies the claim, and older figures such as 67lb 14oz still circulate online long after they were beaten.

For everyday context, UK carp anglers talk in milestones: a double (10lb, about 4.5kg), a twenty, a thirty and a forty. These are angling convention, not official categories, and what counts as a good fish depends heavily on the water.

Mirrors dominate the big-fish lists, but nobody has shown that mirrors grow bigger than commons. Stocking choices may play a part, and the question remains open. For how the record has moved over the decades, see our British record carp history.

Where to Catch Mirror Carp and the Rules That Apply

No bait or rig selects mirrors over commons, so skip the hunt for a special mirror carp bait. Mirrors share water and feeding habits with commons and are widely stocked in commercial fisheries, club lakes and day-ticket stillwaters. Fish for them as you would any carp, using the methods in our common carp guide.

The rules matter more than the tactics.

Rod licence (England and Wales): needed from age 13, including on private fisheries. It is free for 13 to 16 year olds. The standard licence covers 2 rods and a 3-rod version is available. Prices change each April, so check GOV.UK and our fishing licence guide.
Close season (England): 15 March to 15 June inclusive on rivers, streams and drains, on most SSSI stillwaters and on some canals. Most lakes, ponds, reservoirs and canals have none, but local byelaws differ, so check with the fishery and the Environment Agency. See our fishing seasons guide.
Rods (England): the EA national byelaws allow up to 4 rods for coarse fish, with the outermost rods no more than 3m apart, and you must never leave a baited rod unattended. Many fisheries set a lower limit.

Scotland and Northern Ireland have their own rules, so check with the relevant authority before you fish there.

Handling a Big Mirror Carp

Care on the bank matters as much as the fight. A big mirror carp is heavy and awkward to hold, so set up before you cast and keep it out of the water briefly:

Use a large landing net with fine mesh. The byelaws ban knotted or metallic mesh in landing nets.
Unhook on a thick, padded unhooking mat, soaked with water first.
Transfer the fish to a wet weigh sling, zero the scales with the sling on, and weigh quickly.
Keep the fish wet and check it for damage.
Support it upright in the water until it swims away strongly.

The Environment Agency byelaws for England add three hard rules. Release any foul-hooked fish (hooked anywhere but the mouth or throat) straight away. Keepnet mesh holes must be no larger than 25mm in circumference. Any fish you cannot legally keep must go back unharmed. Carp fisheries often set their own keepnet and carp sack rules, so check first.

If the fish is tired, rest it in the net in the margin before you lift it.

Frequently asked questions

Is a mirror carp the same species as a common carp?

Yes. Mirror and common carp are both Cyprinus carpio. The only difference is the scale pattern: commons have an even covering of uniform scales, while mirrors have large, irregular scales with bare skin between. The identification section above has the full comparison.

What is a linear carp?

A linear carp is a mirror with one continuous row of scales along the lateral line, sometimes with a second row along the back. In Kirpichnikov's simplified two-gene model it is an Nn fish. The rest of the flank is usually bare, and a clean, unbroken line is the pattern many anglers prize. See the scale patterns section above for scattered and fully scaled mirrors.

Are mirror carp rare in the UK?

No. Mirrors are common on UK stillwaters because fisheries and clubs stock them widely. No reliable national figures exist for mirrors compared with commons, so treat any quoted ratio with caution. To find out what a lake holds, ask the fishery what it has stocked.

Do you need a licence to fish for mirror carp?

In England and Wales, yes. Anyone aged 13 or over needs an Environment Agency rod licence, including on private fisheries, and it is free for 13 to 16 year olds. See our fishing licence guide. Scotland and Northern Ireland have different rules.