SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdc8c090b3ff9abeba9beba2463a9436f46830d8349f02815443ae7dd5acb735' 
  AND token = '3sIFO2dygohBesESA52H/O0GPuuHwNjAyLzsYaeC/8M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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