What longitude is the Pisces constellation on a star map?

In the celestial coordinate system on the map of the sky, the most visible of the stars
in Pisces ... those that are used when we 'connect the dots' to make the constellation ...
are concentrated roughly between 23h and 2h in Right Ascension, and between the
Celestial Equator and +10° Declination.

The equivalent of "longitude" in the sky is called "right ascension". The center of the constellation goes approximately through right ascension 1 h.