SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0271711f9b5f5564dc24f0d97084fb61393221d5c4b8943fe76f12ee4e6c8442' 
  AND token = 'jmHSBgAyHiuNZ5TK00bziIjli4owsdKGJHdZYjKDiq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}