- head ed ▁s nake ▁T ant illa ▁at rice ps ▁ ▁S out he astern ▁crown ed ▁s nake ▁T ant illa ▁coron ata ▁ ▁Trans - P ec os ▁black - head ed ▁s nake ▁T ant illa ▁c uc ull ata ▁ ▁( former ly ▁in ▁T ant illa ▁rub ra ) ▁Fl at - head ed ▁s nake ▁T ant illa ▁g rac ilis ▁ ▁Smith ' s ▁black - head ed ▁s nake ▁T ant illa ▁h ob art sm ith i ▁ ▁Pla ins ▁black - head ed ▁s nake ▁T ant illa ▁n igr ice ps ▁ ▁R im ▁rock ▁crown ed ▁s nake ▁T ant illa ▁o olit ica ▁ ▁Western ▁black - head ed ▁s nake ▁T ant illa ▁plan ice ps ▁ ▁Florida ▁crown ed ▁s nake ▁T ant illa ▁re lic ta ▁ ▁Ch ih u ah uan ▁black - head ed ▁s nake ▁T ant illa ▁wil co xi ▁ ▁Ya qui ▁black - head ed ▁s nake ▁T ant illa ▁ya quia ▁ ▁Ly re ▁sn akes ▁Son or an ▁ly res nake ▁Tr im orph odon ▁lambda Cal iforn ia ▁ly res nake ▁Tr im orph odon ▁ly ro phan es Tex as ▁ly res nake ▁Tr im orph odon ▁vil kin son ii ▁ ▁( former ly ▁in ▁Tr im orph odon ▁bis cut atus ) ▁Sub family : ▁Nat ric inae ▁Sh ov el - n osed ▁sn akes ▁K irt land ’ s ▁s nake ▁Cl