Slimy Yellow Bolbitius

Native to Australia, the Bolbitius titubans is widespread and common, but varies in size depending on its location.   These are beside the horse poo compost piles which is why they are so “robust”.    According to MushroomExpert.com:  Robust specimens are found on dung and in heavily fertilized soil, while flimsy specimens can be found in grassy areas with less nitrogen.  They are usually short lived and collapse down to a glutinous blob by the end of the day- although these lasted for about three days.   The young mushrooms have a yellow, egg-shaped cap but soon begin to fade and flatten.   The yellow cap is really slimy, but the stem isn’t which means it is grouped as a Phlegmacium (as opposed to Myxacium like the Purple Cortinar which has a slimy cap and stem).   The flesh is also yellow and the gills are
brown.  It is sometimes called the yellow field cap and used to be known as Bolbitius vitellinus.

Rogers Mushrooms says they are Poisonous/Suspect and Bill Leithhead describes the Egg-yolk Toadstool as thin, Mycena-like fungi found near grass and/or dung.