SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e24955ff3af712ebcb7f3a16994517299167030da72a249f4afea35cd1688b3' 
  AND token = 'TMPr1UBSS2IXwGxRoGkQFpmFHO0As8GJ+0ecu89tlig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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