SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1572cd7f74c83a88afe95ae40118c600a7a4d7f4c0a2985a65defdab1874827' 
  AND token = 'I9m8kdkljQcRNQfa3gcF719Lw4HsQGcNrEw7fOE6e4E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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