SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97770a3d75ac2d96e76df90cd077334f709f69173556b81509b24863248c69d8' 
  AND token = 'dC79a2oYBywGy7n3tUeVxQfm6FYrweIIKzKyCViZmdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}