Can't really tell the variety of a volunteer squash. -If the squash you purchased, and then later tossed in the bin, came from a garden where several squash varieties were planted, they will have cross-pollinated and your offspring plant will not necessarily be like the parents. They may be tasty, or they may not be, but they won't kill you if you try them... The silvery markings on the leaves are something that happens in squash plants sometimes.

It is my understanding that all squash are edible. Some that develop hardshells later on are only palatable when young.

Your volunteer almost certainly comes from a pumpkin, a gourd, or winter squash (acorn, butternut, etc.) of some type. These are the types of squashes that have mature seeds that people buy. The summer squashes like zucchini, patty pan and others are usually eaten at unripe, immature stages so no viable seeds for the heap.

From shape, color, and seed cavity at this stage, I'd suspect a pumpkin. Pie pumpkins are very sweet and tasty. Ones grown for carving at Halloween, less so. But roasting and adding some brown sugar and butter will improve the flavor dramatically!

FataMorgana

Here is a link that might be useful: Wikipedia - Squash

Thank you both for the information. Now I can peacefully eat it and give it to friends.
Best,
Viji

It was immature when you picked it but it is known as la estrella.

weirdtrev,
Thank you much. It tasted like the Indian Pumpkin variety that we eat; might have come from the seeds of that Pumpkin that we bought from the local Indian store last year. The skin color was the one that threw as off. The Indian Pumpkin has orange outer skin.
Thanks everyone.

Here is a link that might be useful: