In 2021 I had an amazing experience when exploring North Yilliminning Nature Reserve. There were thousands of cowslip orchids flowering and I discovered fifty cowslip/little pink fairy orchid hybrids (Caladenia flava subsp flava x Caladenia reptans subsp reptans). The reserve is a hybrid hotspot, which occurs when a lot of one parent flowers (cowslip orchid)  are intermixed with a few of the other parent (little pink fairy orchid). In contrast, Foxes Lair has only two hybrids but they are not uncommon in in other reserves, including Claypit Nature Reserve. 
Note. Strong regrowth after fire in 2022 has suppressed orchid flowering in in parts of North Yilliminning Nature Reserve.
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Apparently orchid hybridisation has become more common since the introduction of European honeybees.
​Orchid hybrids tend to be more common in spots where there are lots of one parent and fewer of another. Generally cowslip orchids greatly outnumber little pink fairy orchids, and normally flower for much longer. I noticed that hybrids are much more common on shallow sandy gravel soils, which hold less water than deep sands and sands over clay.  I suspect that hybidisation is enhanced by periodic water shortages. which reduce the flowering period in these soils. In drier seasons, the flowering period for the cowslips on these soils is shortened to that of earlier flowering little pink fairies. Here pollinators are more likely to visit both species together and create hybids.
Hybrids are generally sterile, but expand asexually from root tubers into clumps.

I arranged over 50 images in this Google Photos album. Notice that every plant is different, often in subtle ways.  Differences included flower colour and intensity, colour pattern such as stripes, dots and on tips, and intermixing of column and labellum features from each species . It is a great visual illustration of the complex mixing of genes in offspring of two parents.

Images below show a range of colours and shapes

​Last July I was excited to find my first false truffle (a Rossbeevera species) at Candy Block, which resembled a small half-submerged, blue-tinted potato. False truffles (also known as false puffballs) differ from true truffles in being basidiomycetes rather than ascomycetes.
The smell of the false truffle after cutting was legendary. Think Eau de Dead Roo with a hint of turpentine! This type of fungi sits below soil level, or sometimes at soil level buried under leaf litter. They don’t have a cap that opens up to release spores, but instead, the spores are formed inside the body of the fungus. False truffles resemble puffballs which don’t release their spores. They rely on birds and animals to eat them, the spores passing through the animal’s digestive tract and deposited in their scats.
The woylie has a largely fungivorous diet and will dig for a wide variety of their fruiting bodies.  Although it may eat tubers, seeds, insects the bulk of its nutrients are derived from underground fungi, which it digs out with its strong fore-claws. The fungi can only be digested indirectly. They are consumed by bacteria in a portion of its stomach. The bacteria produce the nutrients that are digested in the rest of the animal's stomach and small intestine. Before white settlement woylies were abundant so there are lots of false truffles around. We neither see nor smell them because they are usually just beneath the ground or leaf litter

A few weeks later I discovered lots of little yellow Rhizopogon species false truffles on the ground adjoining pine trees in the arboretum. Nearly all false truffle species are mycorrhizal fungi, and Rhizopogon was deliberately introduced into pine plantations with slippery Jacks (Suillus luteus) to improve tree growth. These also resembled tiny yellow potatoes, which eventually collapsed into an unbelievably horrible smelling mush (due to them getting wet through borer holes).

​Early fungi classification was very logical with above-ground capped fungi such as agarics and boletes being in a different group to puffballs, earthballs and false truffles. Alas DNA analysis reveals  more complicated relationships with puffballs and earthballs and false truffles spread across groups. One would think that there is a big difference between  capped and ball type fungi, but one overseas agaric rarely fails to open due to a single recessive gene. I can imagine a gradation in the images below.

The very simplified chart below shows that puffballs, earthballs and false truffles have evolved from/with a range of cap fungi. 
Further reading