What species of squash is this?

Volunteer squash grew up in an out-of-the-way part of the garden. Its got one pretty-looking fruit of decent size.

I am wondering what species it is- a pepo or a maxima.   Any thoughts?  Below are pictures. The flowers have an unusual sort of nectar-well that insects crawl into.

Here is just one place that Joseph Lofthouse talks about how to ID squash families.

Thanks Joylynn! I knew that I had seen that before and just could not find the thread!

Crookneck squash (Cucurbita moschata)