SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f505bd4b9298d57129a7b12fde8c174cb993c6f1b2b479b59df89ddd0ed860f0' 
  AND token = 'WnpebgZhGr2PTi2UHidDAqpU5Vrv5wRxRgh+uFrQRAo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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