We all know how difficult it is to identify the sex of these fish, so please post a picture in here and we'll try to help you (or at least give an educated guess!).
I recently acquired two fish of which this is one and which were acquired as both being males ready to spawn. They spent about a month in a Q tank which was well wooded and planted and into which I had placed 3 different caves. The tank has 3 filters- 2 HOBs and a large sponge.
For the first week both fish hid under or alongside the sponge. Then one took up residence in one of the caves which it basically claimed until the fish were moved into my primary breeding tank. the other fish which is the subject of this thread never even went into either of the other caves. It would hide under the sponge or under some of the wood. It was this lack of caving that made me question its sex.
Despite all of the various pleco spawns I have had over the years I am still awful at sexing my fish. I mostly rely on behavior as the way. Females lay the eggs males own caves and raise the kids.
One note- the fish were acquired because it was my feeling i had lost a few males over the years and my colony was short of them. So I decided to add two new males to spur some competition. Instead of spawning all I was seeing was fighting between 2 males. It seems to have had some effect as an unsuccessful almost 2 day trapping ended without success this week. It was the first action in the tank since I lost the last spawn/eggs in the tank in April this year.
What makes the common person uncommon is common sense.
IMO it's a young male....with a little more growing to do.
I have some males that spends most of their time under slates and wood, rarely do they go into caves.