SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f90326b6d01f705aab9f94295c24cdf493b3b16f58e0b5d8c3576f1efc8b636e' 
  AND token = '/AK6aL+0yEHwdloNfcb3uCE+qhlhjV5AhBj1ZqRkPg8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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