SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'edc5bd124f14393fbe376b508096f8861c6dca647bcdcadd43094bd0e36b91e0' 
  AND token = 'QmMNyBSrhABeaOz+04pomkX+UjOnC7qv9Fm/GIoQG6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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