SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e57af60b090558215b77f93729b868097c31e07353c838a33653d01712d325a3' 
  AND token = 'klsIlhkhARyCW/UtgCdwncjmsPSjSWd55uRUWuWv+XU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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