giant sized fish…

[Magnum Man]

yes, I know there are barbs, that get as large as a man… but I guess I’m talking about “little giants”, fish that have arrived or grown much larger than they are supposed to get , by published standards… I’ve had giant Oto’s before, that had arrived nearly double the size they were supposed to get… easily explained by being an unusual fish, so little is known about them… but I have several other examples, some have grown larger, some arrived larger… my newly rediscovered wild caught Limia Islai arrived about 1/3 bigger than the larger size listed on any found published data… and I just saw one of my dwarf orange cray fish, that has grown in my hillstream tank, to every bit of 2 inches, a giant among dwarfs…

any possible explanations for these anomalies???

and any fish you have either acquired, or grown that are much larger than published data???

and is there a practical way to update the published size range on some of these fish??? I expect in this “day and age”,of “copy and paste”, is standard practice so making an effective change to fish information like this has become challenging…

but in some cases, like my limia example, correct information could be vital to choosing the correct tank size, for example… had I known the true potential size of my tiger limia, I likely would not have chosen them to share a 10 gallon with my cherry neocardia shrimp, both from the potential predation, and over stocking of a tank…

 

[GaryE]

This can happen often. There are a few reasons - nutrition, seasons (in some extreme climates adults die young due to warm water), linebreeding for size, lack of predators, etc.

There's also lousy data - I have had Xiphophoris maeyi swordtails that were huge, but if the original catchers got young ones and thought they had X helleri, they would have sold them as such and people would have thought they had fish raising skills that were impossible!

If you see a wild platy and look up the species size, it seems wrong. But I have seen huge pet shop platys that were farm produced hybrids with swordtails, sold as platys. They ARE platys in the commercial sense, but any data for Xiphophorus maculatus doesn't apply to the hybrids.

Plus there's this - the local pet store owner's parents are people I've met. The Dad is above six foot tall, and the Mom around 5"10. He's six foot eight. You're going to get individual variation.

I've had killie females of extraordinary size, oversized wild-type swordtails, a few Cichlids that didn't read their own care sheets and big tetras. But how many wild tetras get to 5 or 10 years old? It might be the potential's there, but predatory fish, insects, birds and mammals take care of that.

 

[TwoTankAmin]

This may be of interest.

Gavriloaie, C. and Oroian, F.C., 2022. Geographic distribution of the genus Limia Poey, 1854. Poeciliid Research, 12(1).

In this paper we propose to present the species of the genus Limia, their geographical distribution and the novelties of the taxonomy within the genus. The genus Limia comprises a group of freshwater livebearers belonging to the family Poeciliidae. Limia species are native to freshwater streams and rivers from Central America and Venezuela. In 2020, two new Limia species were included in the genus: Limia islai, Rodriguez-Silva & Weaver, 2020 (tiger limia), endemic to Lake Miragoâne, Haiti, and Limia mandibularis Rodriguez-Silva, Torres-Pineda & Josaphat, 2020, known from Lake Miragoâne, Haiti. There is currently a total number of 23 recognized species within this genus.
Gavriloaie, C. and Oroian, F.C., 2022. Geographic distribution of the genus Limia Poey, 1854. Poeciliid Research, 12(1).

At one point in the paper you will read this: "Size: Limia species are generally small, with adult sizes ranging from 2 to 6 inches
in length."

I found anpother paper which covers this and here is sizing info:

Rodriguez‐Silva, R. and Weaver, P.F., 2020. A new livebearing fish of the genus Limia (Cyprinodontiformes: Poeciliidae) from Lake Miragoane, Haiti. Journal of Fish Biology, 96(6), pp.1360-1369.

3.1 | L. islai, sp. nov (Figures 2–7)

Holotype: OMNH 86867, adult male 29.5 mm standard length
(SL) (Figure 2). Haiti, Nippes Department, Miragoane, Lake
Miragoane's northern bight, on the roadside of Route Nationale
2. Coordinates 18 25035.400N, 73 02057.700W; R. Rodriguez-Silva,
J. Josaphat, P. Torres-Pineda, B. Pierre Michard, 5 June 2019.
Paratypes: Same origin, collection date and collectors as holotype.
OMNH 86868, 1 female, 35 mm SL and 1 male, 33 mm SL; OMNH
86869, 1 female, 29 mm SL and 1 male, 31.5 SL; OMNH 86927,
1 female, 29 mm SL and 1 male, 25.5 mm SL (cleared and stained
specimens). MNHNSD 22.10650, 1 male, 31 mm SL; MNHNSD
22.10651, 1 female, 33.5 mm SL; MNHNSD 22.10652, 1 male,
28.5 mm SL and 1 female, 32 mm SL; MNHNSD 22.10653, 1 male,
28 mm SL (cleared and stained specimen).

this paper can be found here: https://www.researchgate.net/profil...mes-Poeciliidae-from-Lake-Miragoane-Haiti.pdf

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