SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79da99a67b8991ab0187a2684d74d3b6e85d0232f7ec8d9626eb5cbebd5887b5' 
  AND token = 'pn3nrjW+zWAJLg09HJwYZPXP66GkGJ8f/lvvvi9xxUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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