SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f4cf0ee7f2d458d08238e932fafb00d9a3689f04ce5a9d8f9361964485686c2' 
  AND token = '7zNtkWIKj1ttZ5M6Ob8koYq3GXSHaRJud+rz4pjeNbk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables