SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '979612b80226d4bb4600c2b5a8e8667b33bb4ec5c986570bfd8f47701ca041ae' 
  AND token = '63gPnL8oKH4YMNP3K0+bEwqvLHqQJw+HZnRVWRnMGKg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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