Also in addition to Page 5 there, unless otherwise specifically noted Templates are excluded. For instance, Summon Monster II can Summon an an Untemplated Lemure or a Celestial Eagle, not Half-Dragon versions of either.
And like Summon Monster, Summon Serpents contains no rules saying you can summon a Templated Creature, and it very much has a defined list that doesn't include any Templates or Templated Creatures on it. IE is says Flame Snake, not Paragon Fire Snake of Legend. Even lacking a defined list, it said Serpents, not Fiendish Serpents or Half-Dragon Serpents as the name change of Templated Creatures requires.