Otocinclus ID

[Barb ManParticipant]

I was wondering if these might be different species. Not super important I just didn’t know there was a possibility that they were different species and I noticed that there is only one profile so I couldn’t identify by myself. The first one is a little smaller and I got it after the second and there is one more that I might add later when they want to pose for me seeing as the pictures aren’t that good. Not really sure if anyone can help but any help is good help. I only have three at the time but I am thinking of getting more later

 

[Byron HoskingParticipant]

There is considerable confusion among “otos,” first because there are so many species (and all fish are wild caught), and second because the genus Otocinclus has undergone reclassification with undoubtedly more to come.  Presently, there are 18 accepted described species; names assigned to the fish in stores are not always accurate, and to make it more confusing, there are several species with very similar patterns.  All fish are wild caught (so far as I know) but ascertaining where they may originate is not an easy task in most cases unless one knows the exporter.  There are also other genera with very similar species; some of these are easy to differentiate, such as those in Paratocinclus which have an adipose while no Otocinclus species possesses an adipose.

Otocinclus macrospilus is probably the species most often encountered in the hobby, according to most sources; this species is often mis-identified as O. affinis [see comments below]. It is strikingly similar to O. vestitus and can be distinguished by the markings on the caudal fin. O. macrospilus has a dinstinctive large round black blotch at the base of the caudal fin; on O. vestitus the horizontal black band extends onto the caudal fin with no significant enlargement into a blotch. O. vittatus is another near-identical species, but the upper edge of the black horizontal band along the sides of the fish is bordered by a distinct white clear band separating the black band from the mottled pattern; on O. macrospilus the white band is less distinct in places and on O. vestitus the mottled pattern adjoins the black band with no definable white band.

Concerning Otocinclus affinis, I.J.H. Isbrucker et.al. (2001) proposed the genus Macrotocinclus for O. affinis and O. flexilis on the basis that these two species form a clade according to S.A. Schaefer’s 1997 study; the latter is now regarded as remaining in Otocinclus but Macrotocinclus affinis is accepted [see the California Academy of Sciences database for some comments].  Apparently this species is very rare at least in the hobby.

I would suggest the two fish pictured are the same species.  As to which…O. macrospilus seems likely, but I won’t argue it.  Hope this helps.

Byron.

[BallAquaticsParticipant]

My vote would be for Otocinclus mariae.  Looks similar to te ones I worked with here ==>> http://www.seriouslyfish.com/forums/freshwater-and-brackish-water-fishes/spawning-otocinclus/

The middle fish in the photo is the Otocinclus mariae, the other two are the Otocinclus vestitus.

Dennis

[torsoParticipant]

found this

http://www.remowiechert.de/otobestimmung.html

one question remains for me: how many species? according to fishbase.org 19. didn’t check the list found here (Cas …)

Cheers Charles

[Byron HoskingParticipant]

@torso said:
found this
http://www.remowiechert.de/otobestimmung.html
one question remains for me: how many species? according to fishbase.org 19. didn’t check the list found here (Cas …)
Cheers Charles

I did answer this in my previous post…there are presently 18 described species recognized in the genus Otocinclus.  There are other genera with very similar fish.

Byron.

[Barb ManParticipant]

I think I have two that I can’t really identify and one is probably a little different because the stripe doesn’t connect with the larger section on the tail. I do think that the one is mariae as suggested and the others are probably macropilus. 

Thanks all. I might add some better pictures later to see if anyone can confirm

[MattKeymaster]

Please avoid our Otocinclus profiles for the time being – they need help! 

[JK91Participant]

Taken from PlanetCatfish, a post from Mike_Noren:

“No, vittatus and vestitus can, apparently, only be separated by the number of pore-bearing plates along their sidelines, a character best seen in electron microscope – it is not possible to see in a photo, and very difficult to see even under a stereo microscope (I’ve tried).

However, vittatus is the most common and widespread of all otos, while vestitus has a distribution which suggests it may really be three different species, all with extremely restricted distribution, none of which is in areas where aquarium fish are collected.

In other words, I can’t rule out that your fish is a vestitus, but assuming vestitus and vittatus are not in reality one and the same species, it’s a good bet it isn’t.”

The Oto in the picture doesn’t show the white spot at the end of the tail, so I think we can rule out O. mariae. My bet would be O. vittatus.

[Barb ManParticipant]

I already said that there is another fish that I have along with those two and he looks to be O. mariae because he does have the white spot

[Byron HoskingParticipant]

@jk91 said:
Taken from PlanetCatfish, a post from Mike_Noren:

“No, vittatus and vestitus can, apparently, only be separated by the number of pore-bearing plates along their sidelines, a character best seen in electron microscope – it is not possible to see in a photo, and very difficult to see even under a stereo microscope (I’ve tried).
However, vittatus is the most common and widespread of all otos, while vestitus has a distribution which suggests it may really be three different species, all with extremely restricted distribution, none of which is in areas where aquarium fish are collected.
In other words, I can’t rule out that your fish is a vestitus, but assuming vestitus and vittatus are not in reality one and the same species, it’s a good bet it isn’t.”

The Oto in the picture doesn’t show the white spot at the end of the tail, so I think we can rule out O. mariae. My bet would be O. vittatus.

I would tend to disagree here, meaning with the conclusion that this pictured species [in this present thread] is O. vittatus.  Even accepting that O. vittatus and O. vestitus are impossible to differentiate externally as the cited passage says, there is still the issue of the black blotch on the caudal peduncle and the clear caudal fin.  This would suggest O. macrospilus and not O. vittatus/vestitus for the fish in the photos in this thread, and these two fish appear to be the same to me.

Byron.

[Author]

Posts