SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '244bc5b0a8d12c1f4f7d85399f8d2e269bbe7b84525ad9aa7e19510187b46a7e' 
  AND token = 'lC1+g0ioiqnncTVNDUftALyuyjXlcN+P4NDakjR0rK4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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