SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1e17cae989e14975d29e4cafc70d6b84eb619da18af07fba521793a6a391008' 
  AND token = '44DVhzVOYJk7pxAZBhfW22AN9wIwKKSRKeQ/xb/0Hv8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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