SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '160a5146c7f9c6b946bfcce802f5bd9104e18c20672a228873336603034316a9' 
  AND token = 'nRho56i54wMNmhHLzFxqxHWuPoUk0QWAsml/IW4uGP4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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