SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85f6d446b10cb0ef91cc59347b8b1955bf6ddf27a1aea95cb7a37e91168464cf' 
  AND token = '2ZXoRG8/VIwKeHRPexK+T8O+vGi5nCylZzm9T3BN+B4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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