SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1c67db1c755364a49d0a8fc93f694035df23dc3308aff57140c2acf669a25e5' 
  AND token = 'WqB4xBdXN997+jG4CH3WipRfsxcGomIFyExCD/cK3+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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