SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd971db989a58de197786751729fed2224ea1dc9575735d92c54d9e807be2877a' 
  AND token = '6ar8/9Cu8cmz/ovI4++XkypjHmnvA1ijLO0kvYF3jSs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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