SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '42d16a72b2ce54873371c53e4bdba900c5c4969691a499e87ab1534f7de4d83c' 
  AND token = 'jU/Z/H9aJIbQWqP9miBzJImcRPZsuKB5KCfxH9lAJ7w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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