It is possible that it is one of the five subs built in Shreveport. One was disassembled, and shipped by rail, to either Houston or Galveston. I have never heard anything else as to its fate.

However, in Lt. Jonathan Carter's letterbook , there are two entries.

Jan. 17th 1865, to Sec. of the Navy, Hon. S.R. Mallory
(second paragraph)
"...A torpedo boat is now in course of construction near Houston by the Engineer Department. She will probably be completed by spring."

April 5th 1865, to Hon. S.R. Mallory
(seventh paragraph)
"I have ordered Lieut. Phillips to Texas to take command of a Torpedo boat built near Galveston by the Engineer Department."

It seems more than mere coincidence that this vessel is the fifth torpedo boat built in Shreveport. Especially with Carter's involvement. It is, or course, possible that a separate torpedo boat was built in the Houston area, but, given to the circumstances of the time, it seems unlikely.