I spend a lot of time on iNaturalist changing identifications of Robust Bracket (Fomitiporia robusta). It seems many people think any perennial brown bracket is Fomitiporia robusta (or are directed to do so by the software suggestions), so decided to make a general post to clarify the issue.

There are two main problems with using Fomitiporia robusta for Australian species:
(1) there are MANY species (and many genera) of perennial brown brackets (Hymenochaetaceae) in Australia, not just one;
(2) The type locality of Fomitiporia robusta is Finland, and there are no confirmed (DNA-confirmed) collections of Fomitiporia robusta from Australia - so it is very likely that the name does not even apply. There are however several native species of Fomitiporia, and records of F. robusta are probably misidentifications of those.

So at least the majority of past Australian records of ‘Fomitiporia robusta’ are not this species, and some are not even Fomitiporia. The reason for misunderstanding is probably that, in most Australian field guides, the only perennial Hymenochaetaceae species covered is called "Phellinus robustus" (=Fomitiporia robusta). However single species does injustice to the wide diversity of medium to large perennial Hymenochaetaceae in Australia, which includes at least 40 species of Inocutis, Fomitiporia, Fomitiporella, Fulvifomes, Phellinus, Pseudoinonotus, Pseudophylloporia, Sanghuangporus, and Tropicoporus.

So merely knowing that you have a perennial brown bracket is insufficient even to place it to genus, and the best identification is simply "Hymenochaetaceae".

to go further than family, you need to know additional information. Host plant, spore colour (white, yellow or brown), pores per mm, cap cracking, and flesh consistency are necessary characters to identify perennial Hymenochaetaceae to either genus or species. For full species identification microscopic characters (spore dimensions, spore wall thickness, and setae) are often necessary.

For perennial, pileate, medium to large species:
Spores white = Fomitiporia, Phellinus, Pseudoinonotus, also compare Fuscoporia and Pyrroderma
Spores yellow = Fulvifomes, Inocutis (plus a few odd species of other genera)
Spores brown = Fomitiporella, Fulvifomes, Pseudophylloporia, Sanghuangporus, and Tropicoporus

Beyond that, key characters to distinguish species are: plant host (especially whether Eucalyptus, Melaleuca, Acacia or other), whether host is living or dead, pore dimensions, cap surface cracking, internal flesh colour, whether there is a granular or marbled core at the base in section, whether the flesh is homogenous or divided into two layers separated by a thin dark line, and whether tropical or temperate distribution. Tropical and subtropical areas have the greatest diversity.

Fortunately most genera have only a few pileate species, so knowing the above characters gets you a long way to identifying to species. Unfortunately, many species remain undescribed, and new species or new Australian records are discovered regularly, so we are a way off having a comprehensive key to them all.

For now, please just use Hymenochaetaceae if you are unsure, and when collecting, do your best to locate spore deposit under the bracket. You can often see spore colour by spore caught in spider web just below the fruitbody close to the trunk. If you can see spores, please record it, along with the host tree identify, when making your iNaturalist record.

A good discussion on current (unpublished) knowledge of Fistulina can be found under this observation: https://inaturalist.ala.org.au/observations/112243045

Here is a link to my recent presentation on Australian polypores, collection and identification tips to the Queensland Mycological Society, ~1 hour.
Thanks Wayne Boatwright and the QMS for arranging and recording this talk!

https://www.youtube.com/watch?v=t1JhuzeGzfA

Since people keep asking about Trametes specifically, I have written a PRELIMINARY key to Australian species.

Note: this is preliminary only, several other species may occur but are not confirmed, and characters may not always work, especially in older specimens. Since so many records turn out to be different from what they were initially identified as, I only accept species that are vouchered by herbarium collections AND have sequence information - otherwise the list of Trametes would be unrealistic and full of errors. But almost certainly we have more species than what is keyed below - but the missing species are probably mostly rare and tropical.

Note that many other genera ("Coriolopsis", Datronia, Fomitopsis, Funalia, Neofomitella, Rhodofomitopsis and others) can be mistaken for Trametes - this key is ONLY to the core Trametes clade, which is not easy to delimit, even with microscopy. A larger key to all genera species is some time away.

Note that there is an ongoing argument among experts about how to treat genera in the Trametes-lineage. Some people argue for a large Trametes, including Pycnoporus, and this has been taken up by iNaturalist (at least pro tem). Other people argue for splitting Trametes into Artolenzites, Cellullariella, Coriolopsis, Cubamyces[=Leiotrametes], Pilatoporia, Sclerodepsis, and Trametes s.s. [including Lenzites], which means keeping the popular scarlet bracket genus Pycnoporus intact. I have keyed them all together as Trametes, but indicated alternate genera as well (if not alternate genus is mentioned, they are Trametes in the strict sense).

Preliminary, unpublished key to Trametes in Australia.
Key to informal morpho-groups:

1. Context and pores bright red or orange Group 1 [Pycnoporus]
   1: Context and pores white, buff, yellow or pink. 2

2. Lamellate or elongate-pored. Group 2 ["Lenzites"-like forms, which are not a natural group]
   2: Pored, the pores at most 3x longer than wide. 3

3. Pileus distinctly hairy, at least in some zones (handlens required, look at youngest specimens). Group 3
   3: Pileus glabrous to scrupose or granular-tuberculate (check youngest specimens). Group 4

Key to Group 1 [Pycnoporus clade]

1. Pores 1-4 per mm [usually > 5 mm thick at base]. 2
   1: Pores 4-8 per mm. 3

2. Fruitbodies small (up to 5 cm diam.), ??6-10 mm thick; pileus surface usually scrupose, dark orange- red. Rare tropical species. Trametes/Pycnoporus puniceus
   2: Fruitbodies usually larger; mosly boreotemperate; pileus surface matt, smooth, bright orange. Trametes/Pycnoporus cinnabarinus (VERY rare in Australia, known from a single specimen near Darwin)

3. Fruitbodies thin, 1-4(-5) mm thick at base, often narrowly attached to pseudo-stipitate; pileus smooth to sub-varnished, usually weakly zonate, colour not fading except in extreme age, most specimens not or scarcely faded; pantropical, strictly tropical in Australasia (not occurring in SA, NSW, VIC, TAS, southern WA, or central deserts - all records in these states are T. coccineus). Trametes/Pycnoporus sanguineus
   3: Fruitbodies thicker, usually > 5 mm thick at maturity, always broadly attached; pileus surface azonate, when fresh dull and minutely velvety, becoming smooth and sub-agglutinated in age; mostly temperate Australia and NZ, rare in tropical areas of Australia, Australasia and Oceania. 4

4. QLD, SA, NSW, VIC, TAS, southern WA, or central deserts. Extremely common except in tropical areas. Trametes/Pycnoporus coccineus
   4: Kimberley, Top End (possibly also Cape York). Very rare. 5

5. Trametes/Pycnoporus sp. Kimberley, and rare Trametes/Pycnoporus coccineus (DNA sequencing is required to be certain of identity)

Key to Group 2 [lamellate forms]

1. Elongate-poroid, labyrinthine, the elongate pores / lamellae 10-30 per cm when measured transversely; pileus ±glabrous, usually white to cream. Trametes/Artolenzites repanda
   1: Elongate pores / lamellae 5-8(10) per cm when measured transversely. 2

2. Pileus mostly pale to dark brown; context and/or hymenium often with brownish to tan colours. Trametes tenuis [=Lenzites acutus, Cellullariella acuta] [Poorly characterised in Australia, this step may not work for all forms]
   2: Pileus white to cream, or in age pale brown in centre only. 3

3. Pileus whitish with asperulate tufts of agglutinated hyphae, often in zones. Common in wet tropics, mostly in rainforest, possibly more widespread in wetter tropical areas of Australia. Trametes vespacea
   
   3: Pileus whitish aging pale brown in centre, smooth, matt, azonate. Common and widespread in, tropical and subtropical Australia. Trametes/?Cellullariella warnieri

Key to Group 3 [Pileus tomentose to hispid hairy]

1. Pores 1-3 per mm. Only known from Wet Tropics in Australia. Trametes pocas [if pileus VERY hairy, compare Funalia leonina and F. subgallica]
   1: Pores 3 or more per mm. 2

2. Hymenium becoming greyish or black with age (From Li et al 2011, need to confirm is a reliable character in Australia). Southern and eastern Australia. Trametes hirsuta
   2: Hymenium remaining pale. 3

3. Pileus distinctly coloured, with a black line between context and tomentum. Southern and eastern Australia, mostly temperate. Trametes versicolor
   3: Pileus white to ochraceous, or pale brown, without a dark line between context and tomentum. Northern and Eastern Australia, mostly tropical and subtropical. 4

4. Context pale brownish, surface ±hispid??. Trametes/Coriolopsis polyzona
   4: Context white to cream. Trametes pavonia

Key to Group 4 [Pileus ±smooth, granular, scrupose, tuberculate but not hairy]

1. Pileus 1-2 per mm. Trametes/Cubamyces lactinea
   1: Pores more than 3 per mm. 3

2. Pileus smooth or sometimes irregularly tuberculate near centre. common in tropical and subtropical Australia. Trametes/Pilatoporus muelleri/marianna [this is what has been called T. marianna in Australia, but I am uncertain whether the two species are really the same, or closely relate sister species - until resolved i prefer to use the Australian name muelleri]
   2: Pileus strongly granular over most of surface. Rare, so far only known from Wet Tropics, but may be more widespread. Trametes ?manilaensis [exact identity awaiting DNA sequence]

Like mushrooms, polypore fungi release spores from their under-surface (hymenium) that can be collected, either naturally below the fruit body or artificially on a paper or glass surface - a 'spore print'. However, there are a few tricks with polypores.

Most polypore have colourless spores, and produce a white spore print. The spore print COLOUR is therefore of limited utility for some groups (spore size, shape, ornamentation and iodine / dye reactions provide many characters, but require a high-powered compound microscope, at least 400X magnification, preferably 1000X). However in other polypore groups (especially the rusty-brown-fleshed Hymenochaetaceae, which includes Inonotus, Phellinus and their relatives) the spore print can be white, yellow or brown, and is extremely useful for distinguishing between these otherwise feature-poor fungi. So white spore deposits are useful to know, but yellow to brown is more diagnostic, as they are the more rare condition.

The first thing I do, before disturbing the fruitbody, is examine the surrounding area immediately below the pore surface to see if there is a dusting of spores. It can sometimes be on the upper surface of caps when they are shelving in layers, or on the wood closest to the base, or often on spiderweb on the underside of the fruitbody. Specimens fruiting on the underside of logs can drop their spores directly onto the soil surface. If you find such deposits, photograph it if possible, or at least make a note of it and add it to the iNaturalist post.

If there is no spore deposit and you want to try to make a spore print, the procedure is basically the same as for mushrooms: use a piece of white paper or better a glass slide (it is easier to see weak and white deposits on glass) and place the fruit body directly above it, then cover the whole thing with a cup or bowl to prevent air currents dispersing the spores - you are trying to get a good seal all around the edges. Leave it for 4-14 hours; any longer and you are likely to encourage molds. Cutting the fruit-bodies to make them fit is ok, but the less cutting the more likely it is to drop spores.

However, you must consider humidity in this process. Polypores, especially the tough ones, can dry out completely, before suddenly reviving and releasing spores - in some cases after being picked, air-dried, then re-wet months later! Conversely, sometimes they do not release spores even under seemingly optimal conditions. So if the fruitbody seems fresh and actively growing you have a reasonable chance of getting a spore print, provided you keep the fruit body moist but not wet in transit. Either collect into a fishing-tackle box, or wrap in grease-proof paper. Never put it in a zip-loc bag for more than a few minutes, as it will sweat and start to grow molds, or else start to rot. Unless it is really fresh, I recommend putting a small vial of water (e.g. an overturned bottle cap) under the covering bowl

If the fruit body is too dry, you can TRY re-moistening it in water; dunking the non-pore surface in water can help, or just drip water gradually onto the non-pore surfaces until it seems rehydrated, but NOT DRIPPING, as fungi shut down when waterlogged. Do the spore print as above, and definitely include the vial of water to maintain humidity.

If you are using paper, outline where the fruit body sat, shine incident light on the print, and change the viewing angle to visualise the spore deposit, which can be subtle.

Another very useful method, which is sometimes the only way possible: tape paper or a glass side under the fruit-body in-situ, still on its tree, leave overnight and examine the next morning. You must leave at least a small air-gap to prevent sweating and just collecting water-drops - any condensation must be able to evaporate. Sometimes it can take several days for exactly the right conditions.

If you are collecting the fruit body for a herbarium, making a spore print is VERY beneficial, because many polypores drop all their spores, leaving nothing in the fruit body, and spores can be absolutely essential for identification. So even if it doesn't seem useful, someone identifying the fungus later will be extremely grateful!

If you have got to this post, you are hopefully interested in learning more about polypore fungi, and contributing to the knowledge on this fascinating but difficult group of organisms. It is my intention that this project can be a central source for methods on photographing, collecting and identifying Australian polypores.

Unfortunately data on Australian polypores lags behind the rest of the world. The only whole-sale treatment is that of Gordon Cunningham from 1965, more than 50 years ago! And even then the Australian species were treated more as background information for New Zealand species. Most of the collections he studied were housed in Kew, UK, from 19th-century collectors. Very few tropical species were included, and no field-work was conducted.

Since the work of Cunningham, there have been scattered revisions of some groups, a range of type studies by Peter Buchanan (NZ) and Leif Ryvarden (the Norwegian polypore guru), and some localised all-taxa surveys (e.g. Genevieve Gates and David Ratkowsky in Tasmania, and Neale Bougher in Perth) that resulted in records of new species, or collaborations with overseas taxonomists to describe new polypores. A recent (and ongoing) flurry of work by Chinese polyporologists (especially Yucheng Dai, Li-Wei Zhou and others) has improved our knowledge for certain groups.

However, none of these are long-term systematics projects evaluating polypores Australia-wide. After 25 years of accumulating data on Australian polypores, and making >1000 collections, I have concluded that the Australian polypore 'flora' consists of well over 500 species, probably 700-1000 species. Numerous species known from south-east Asia also occur in northern Australia. Many of the names previously reported from Australia are incorrectly identified, or part of species complexes that ultimately mean the Australian species is not as reported. So nothing less than a systematic revision can clear up the innumerable problems of polypore taxonomy in Australia.

In order to make progress, it is necessary to validate each name in turn, based on:
-Permanent reference specimens housed in a herbarium, that have associated:
--Photographs of all parts
--Microscopic description
--DNA sequence(s)
Once all this data is accumulated (ideally from multiple collections to assess within-species diversity), it requires careful comparison with the world literature to ensure that the correct name is applied (or a new species described). This data needs to be published in a peer-reviewed journal to ensure there is a permanent record and (taxonomic) community consensus.
Only when we have done this for a significant proportion of our species can we be reasonably sure of how many species we have, and what are the diagnostic characters we need to distinguish them.

In spite of these knowledge limitations, iNaturalist is a perfect place to collect image galleries for identification, either now, or later update when we know more. However, I strongly advise following a simple procedure of photographing specimens to maximise the likelihood that the specimen can be identified. That includes images from above (cap) and below (pores), flesh (section), attachment to the substrate, host plant (if identifiable, much dead wood is not recognisable), and habitat. In handling the fruit body you can often notice other diagnostic characters, such as bruising colour changes, colour of spore deposits below the pores, smells, or variation between fruit-bodies.

There are some weird and wonderful fungi out there, and some amazing discoveries to be made, even in urban parks. Happy exploring, and I hope this project is a useful resource for you.

Matt Barrett
Australian Tropical Herbarium, Cairns, Queensland