Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab6e20c91c547ce20c6ad6bc876b51118f48cf17b9be6d62003de30e0bcaedbc' 
  AND token = 'R3XmznpIeRx5azyigu3KXyGq1X11fscSqFJ/jA60BJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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