SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '645b67c8f979fcec2b464cd59fd679a65d9c1372fff254c54ab93dcd18a97c84' 
  AND token = 'a+zfwJA6mf3xEBBTFe/gJJYD7fxTsKewRnV9mNLE7uc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}