# How Many Species of Fish?

**URL:** <https://boards.straightdope.com/t/how-many-species-of-fish/320443>\
**Category:** Factual Questions\
**Created:** [September 7, 2005, 12:37am UTC](https://boards.straightdope.com/t/how-many-species-of-fish/320443 "2005-09-07T00:37:16Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![shelbo](https://avatars.discourse-cdn.com/v4/letter/s/3d9bf3/32.png) [@shelbo](https://boards.straightdope.com/u/shelbo)\
**Post date:** [September 7, 2005, 12:37am UTC](https://boards.straightdope.com/t/how-many-species-of-fish/320443/1 "2005-09-07T00:37:16Z")

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Third grade stumper of the day:

How many fish species are there?

Obviously, there are probably many unidentified species, so I think the question must be read to include only identified species. I guess I’d also rule out extinct species. Even so, I’d think there should be a precise number of currently identified species.

Anyone have a decent answer?

(Don’t worry, it’s not homework!)

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**Author:** ![wevets](https://avatars.discourse-cdn.com/v4/letter/w/e9a140/32.png) [@wevets](https://boards.straightdope.com/u/wevets)\
**Post date:** [September 7, 2005, 12:46am UTC](https://boards.straightdope.com/t/how-many-species-of-fish/320443/2 "2005-09-07T00:46:12Z")

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IIRC from Ichthyology, there are about 24,000 identified species of fish.

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**Author:** ![wevets](https://avatars.discourse-cdn.com/v4/letter/w/e9a140/32.png) [@wevets](https://boards.straightdope.com/u/wevets)\
**Post date:** [September 7, 2005, 12:52am UTC](https://boards.straightdope.com/t/how-many-species-of-fish/320443/3 "2005-09-07T00:52:06Z")

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I was pretty close. Consulting Nelson, JS. 1994. Fishes of the World (3rd Ed.) there are about 25,000 identified species and 55,000 named species and subspecies. That’s over 10 years old, so it must be more than that by now (depending on the splitters, not the lumpers, winning the taxonomic battle).

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [September 7, 2005, 12:52am UTC](https://boards.straightdope.com/t/how-many-species-of-fish/320443/4 "2005-09-07T00:52:41Z")

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According to [this page](http://biology.usgs.gov/s+t/SNT/noframe/cr135.htm), there were 24,618 known fish species as of 1994 as tabulated by one researcher.

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**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\
**Post date:** [September 7, 2005, 2:32am UTC](https://boards.straightdope.com/t/how-many-species-of-fish/320443/5 "2005-09-07T02:32:39Z")

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It’s never possible to come up with a precise number of species for any group, since different authorities may disagree as to which forms are full species and which are subspecies. However, 25,000 is a good estimate for the total of described species, with estimates of about 30,000 or so for total species including undescribed forms.

Note that “fishes” include members of 4 different vertebrate classes: Myxini, or hagfish; Cephalaspidomorphi, or lampreys; Chodrichthyes, or cartilaginous fishes; and Osteichthyes, or bony fishes.

The number of species in each group, from [here](http://users.tamuk.edu/kfjab02/Biology/Vertebrate%20Zoology/b3405_ch01.htm):

```auto

Myxini
Myxinoidea 40 hagfish

Cephalaspidomorphi
Petromyzontia 41 lampreys

Chondrichthyes                        
        Elasmobranchii 810 sharks, skates, rays
        Holocephali 30 ratfish (=chimaeras)

Osteichthyes
Actinopterygii
        Brachiopterygii 13 reedfish, bichirs
        Chondrostei 25 sturgeon, paddlefish
        Lepistosteus 7 gar
        Amia 1 bowfin (=choupique)
        Teleostei 25,000 tarpon, herring, perch, etc.
Actinistia 2 coelacanth (Latimeria)
Dipnoi 6 lungfish

```

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**Author:** ![Stan\_Doubt](https://avatars.discourse-cdn.com/v4/letter/s/53a042/32.png) [@Stan\_Doubt](https://boards.straightdope.com/u/Stan_Doubt)\
**Post date:** [September 7, 2005, 4:09am UTC](https://boards.straightdope.com/t/how-many-species-of-fish/320443/6 "2005-09-07T04:09:24Z")

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You/your student(s) might have some fun looking at [Fishbase.org](http://www.fishbase.org), which lists a number disturbingly close to those posted by **Colibri**. I like this site because it tends to attract contributors from around the globe, not just U.S. / Western researchers.