Ubeto, who joined Lampre this year, returned a sample that showed traces of GW1516, also known as GW501516, following an out-of-competition test taken on April 16, the UCI said in a statement.
"The provisional suspension of Mr. Miguel Ubeto Aponte remains in force until a hearing panel convened by the Venezuelan Cycling Federation determines whether he has committed an anti-doping rule violation," the UCI said.
Ubeto can ask to have the B sample tested.
WADA issued a warning about the once developmental drug in March, saying it had been withdrawn from research but was available on the black market and contained "serious toxicities".
A Lampre team statement said: "Ubeto Aponte had not yet made his debut with the team jersey, due to an injury.
"While waiting to receive information and any clarification from Ubeto Aponte and evaluate additional measures, the team reiterates its support for all efforts to make cycling more clean and credible, severely condemning any behaviour violating anti-doping rules."
European track champion Valery Kaikov of Russia last month became become the first rider to test positive for GW1516 .
- Sports & Recreation
- Venezuelan Cycling Federation