SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05c62346588e86c70a8745e2d094c6a36a3c79f93e1cdb689e0df86af9893d5e' 
  AND token = 'efZkONiIglnqNmSLuxi6TZoabLye4edqiHOABZkIH18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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