Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8015c90e2a3bb0127a44ebdceabda8521ed5393bba92baf64496d54398c40c0' 
  AND token = 'k8U6/jgbFUp+1ml/Tk+d+tiKWb3XLh8YBn08eXWbUbY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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