SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0fddfd05877d977325c9a24c303d0c726597b23926b0adc1491fb2811e629440' 
  AND token = 'KbFGTX6jHV03GWdMAHSnJM4DkhRTOoqWAv+XRqqiZMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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