Numbers of Living Species in Australia and the World

Detailed discussion by Group

Others

The other groups are difficult to determine and characterise. Many are generally included among the protists—a loose assemblage of primarily single-celled, both autotrophic and heterotrophic, eukaryotic organisms of which the colourless forms were previously called protozoa (Brusca and Brusca 2003, Hallegraeff pers. comm.¹⁴³). It is often difficult to know what constitutes a species in many groups, and to determine in what Kingdom the various phyla should be placed or whether (as in the case of Chromista etc) they form a Kingdom of their own. Molecular phylogenetic and cladistic studies have resulted in major reorganisations of eukaryotic groups of organisms (see Meeûs and Renaud 2002). Many species previously included with algae or fungi have now been split from those groups and are included in this report under the Chromista, Cyanophyta or Protoctista. The green algae, red algae and glaucophytes, etc treated under the ‘Others’ section in the previous report, have been included under plant algae in this report. The fungi that were treated under the ‘Others’ section in the previous report, have been placed in a separate section of their own, excluding the chromistan and protoctistan fungi which are treated separately.

Prokaryota (Bacteria [Monera] of previous report¹⁴⁴)

The estimates of numbers of Prokaryota in the world (and in Australia) are complicated by many factors. It is generally believed that many species cannot be cultivated or identified, using existing techniques. The Cyanophyta (Cyanobacteria) have been treated separately.

The estimated number of described bacteria species in the world varies from 3 000–4 000 (Hawksworth and Colwell 1992) through 4 000 (Hawksworth and Kalin-Arroyo 1995), 4 760 (McNeely et al. 1990), 5 432 (Euzéby 2004), 7 643 (Euzéby 2009) to 10 000 (Groombridge and Jenkins 2002). I have accepted the figures of Euzéby (2009). Shimura (2004) provided a figure of 8 500 species, but from Euzéby (2004) it is obvious that these are names, and as stated by Euzéby (2009) of the 9 435 currently validly published species names, these apply to just 7 643 currently accepted species names.

Estimates of the total number of species (described and undescribed) vary from 50 000 to 3 million (Hawksworth and Kalin-Arroyo 1995) with generally accepted figures varying from 400 000 (Groombridge and Jenkins 2002) to 1 million (Hawksworth and Kalin-Arroyo 1995).

Figures for Australia are virtually non-existent other than an estimate of 40 000 for the total number of species in Australia by Saunders et al. (1996). These authors also gave a figure of 0.1% described which would indicate a figure of about 40 species. This appears to be a gross under-estimate for the number of described species. No further information has become available since the previous report (Chapman 2006).

World Described/ Accepted minimum		World Described/ Accepted maximum		World Described/ Accepted		World Estimate		Australia Described/ Accepted		Australia Percentage		Australia Estimate		Australia Endemic		World Threatened 145		Australia Threatened		Australian Threatened as % of World Threatened
3 000		10 000		7 643		400 000–1 000 000		~40		0.5%		40 000		unknown		0		0		–

Cyanophyta (Cyanobacteria)

The Cyanophyta are an important group in Australia, although comparatively little is known of them.

Watanabe et al. (2004) gave the number of described species in the world at about 3 234. Groombridge and Jenkins (2002) reported that there are about 1 000 genera. Hoek et al. (1995) gave 150 genera and about 2 000 species for the Class Cyanophyceae, whereas AlgaeBase (Guiry and Guiry 2009) lists 2 664 species in the Class. I have accepted the figure from AlgaeBase which is lower than the figure I cited in the previous report (Chapman 2006).

Actual diversity is very difficult to determine, but the total number of species of cyanobacteria in Australia is unlikely to exceed 500 (McCarthy pers. comm.).

Entwisle and Huisman (1998) provided an estimate for the blue-green algae (Cyanobacteria) in Australia of 270 made up of 10 Chamaesiphonales; 60 Chroococcales and 200 Nostocales/Oscillatoriales.

Order	World (AlgaeBase) Described/Accepted	Metting (1996) Estimate	Australia (Entwisle & Huisman 1998)
Chroococcales	711		60
Nostocales	686	1 000	200
Oscillatoriales	584	1 000
Pseudanabaenales	325		–
Stigonemetales	3		–
Synechococcales/Chamaesiphonales	355		10
TOTAL	2 664	unknown	270

World Described/ Accepted minimum		World Described/ Accepted maximum		World Described/ Accepted		World Estimate		Australia Described/ Accepted		Australia Percentage		Australia Estimate		Australia Endemic		World Threatened 146		Australia Threatened		Australian Threatened as % of World Threatened
3 234		3 234		2 664		unknown		270		10%		~500		unknown		0		0		–

Chromista (including some species previously included under either algae or fungi)

Again, it is difficult to estimate the number of species of chromistans, partly due to varying circumscriptions of the group. Summaries for the various classes and phyla, where available, are given in the accompanying table.

Estimates for the number of described species of chromistan ‘algae’ (i.e. chromistan species previously regarded as algae) are difficult to determine due to the circumscriptions of different authors, and the separation into Plantae and Chromista by some but not others. The biggest deficiency is in the Bacillariophyta (diatoms) where AlgaeBase (Guiry and Guiry 2009) records just 5 530 species ‘but no clarity on what is what’ (Guiry pers. comm.¹⁴⁷). Guiry (pers. comm.) goes on to estimate that there are about 20 000 published species of diatoms. Hallegraeff (pers. comm.¹⁴⁸) states that diatoms exhibit prominent morphological diversity of characters but molecular sequencing is now indicating that they have been overclassified. I have used the figure of 23 605 for the world for the chromistan ‘algae’ based on the numbers in AlgaeBase—see table below. Chromista species previously regarded as fungi (chromistan ‘fungi’) are also not well known. Kirk et al. (2008) report 1 039 species for the world. Recently, Class Opalinea has been moved into the Chromista (Nishi et al. 2005) but with little certainty of where it is placed within the group. Some authors (e.g. GBIF 2009b) still retain it in the Protoctista under the Phylum Sarcomastigophora. Both Corliss (2000) and Adl et al. (2007) reported figures of 400 published species of Opalinea, while Patterson (pers. comm.¹⁴⁹) suggests that there are about 300 species worldwide.

Few estimates of the total number of chromistan ‘algae’ have been found, however Hawksworth and Kalin-Arroyo (1995) gave a figure of 400 000 (for all algae) with cited estimates ranging from 150 000 to 1 million, while Biodiversity: the UK Action Plan (Anon. 1994) suggested that there could be up to 10 million species of diatoms. Michael Guiry (pers. comm.¹⁴⁷), the manager of AlgaeBase (http://www.algaebase.org), reports that there are about 20 000 described species of diatoms with about another 80 000 undescribed species. The data from AlgaeBase indicate that a figure of 400 000 is too high, and I have settled on a figure of about 200 000 (assuming 100 000 species of diatom) which is at the lower end of the range reported by Hawksworth and Kalin-Arroyo (1995). For Opalinea, Adl et al. (2007) provided an estimate of about 500 species. I have no estimates for the total number of world Chromista species previously regarded as fungi.

I have found no comprehensive list of Australian species of Chromista. For the species previously regarded as algae I have relied largely on AlgaeBase (Guiry and Guiry 2009), but not all species there have distribution records, so where other data are available, I have cited those in preference. Scott and Marchant (2005) list 187 species of diatoms in the Class Bacillariophyceae for the Australian Antarctic Territory.

Estimates for the total number of species of chromistan ‘algae’ in Australia have been taken largely from Entwisle and Huisman (1998). Patterson (pers. comm.¹⁴⁹) states that there are about 20 species of Opalinea in Australia. It would appear that most of the Australian species occur as parasites of the intestines of frogs. May (pers. comm.¹⁵⁰) provided the figures for chromistan species previously regarded as fungi.

DEH (2001) and ABRS (2004) reported that there are 10 000–12 000 species known for Australia, but ABRS (2004) suggested that ‘this is certainly an underestimate’. I have followed the figures of Entwisle and Huisman (1998), but using the higher of their estimates in most cases.

	World Described/ Accepted minimum		World Described/ Accepted maximum		World Described/ Accepted		World Estimate		Australia Described/ Accepted		Australia Percentage		Australia Estimate		Australia Endemic		World Threatened 151		Australia Threatened		Australian Threatened as % of World Threatened
Chromistan ‘algae’	23 605		44 000		~23 605		200 000		2 044		8.7%				unknown		6 (0.03%)		0		0%
Opalinea	300		400		400		500		~12		3.0%		~20		unknown		–		0		–
Chromistan ‘fungi’	1 039		1 039		1 039		unknown		74		7.0%		unknown		unknown		–		0		–
TOTAL	24 944		45 439		~25 044		~200 500		~2 130		8.5%		>15 000		unknown		6 (0.02%)		0		0%

Chromistan ‘algae’ (species previously included in the algae)

Phylum	Class	World Described/Accepted						World Estimate		Australia Described/Accepted		Australia Estimate
		AlgaeBase (Guiry & Guiry 2009)		Corliss (2000)		Adl et al. (2007)		Adl et al. (2007)		AlgaeBase (Guiry and Guiry 2009) unless otherwise noted		Entwisle & Huisman (1998)
Bacillariophyta (diatoms)	Bacillariophyceae	4 256								187152
	Coscinodiscophyceae	933								57153
	Fragilariophyceae	339
	ENTIRE GROUP	~20 000154		10 000–20 000		10 000–20 000		200 000		1 300155		13 000
Cryptophyta (cryptomonads)	Cryptophyceae	127								14		50
	ENTIRE GROUP	127		~200		70		200		14		50
Haptophyta (yellow brown algae)	Haptophyta (incertae sedis)	123								10		–
	Pavlovophyceae	15								1		4
	Prymnesiophyceae	273								42		155
	ENTIRE GROUP	411		500		350				53		159
Heterokontophyta (golden and brown algae)	Aurearenophyceae	1		–		–		–		0		–
	Bicosoecophyceae	21		~40		72		100		3156		16162
	Bodonophyceae	28		–		–		–		1156		–
	Bolidophyceae	2		–		–		–		0		–
	Chrysophyceae	374		~1 250		1 000		2 000		80157		300
	Dictyochophyceae	44		~200		15		30		4		20
	Eustigmatophyceae	35		–		15		30		4		–
	Pelagophyceae	10		–		12		20		0		–
	Phaeophyceae (Fucophyceae)	1 778				1 500–2 000		2 000		451158		308–318
	Phaeothamniophyceae	26		–		25		40		1		–
	Pinguiophyceae	6		–		5		20		1159		10
	Raphidophyceae	23				20		40		2		–
	Schizocladiophyceae	4		–		–		–		0		–
	Synchromophyceae	1		–		–		–		0		–
	Synurophyceae	284		–		200		350		60160		40
	Tribophyceae/ Xanthophyceae	430		–		600		800		70161		25
	ENTIRE GROUP	3 067		3 126		3 464–3 964		5 430		677		790–800
TOTAL		~23 605		~13 826–23 826		~13 884–24 384		~206 030		2 044		~13 999–14 009

Opalinea

Phylum	Class	World Described/Accepted				World Estimate		Australia Estimate
		Corliss (2000)		Adl et al. (2007)		Adl et al. (2007)		Patterson (pers. comm.162)
Incertae sedis	Opalinea	400		400		500		~20
	TOTAL	400		400		500		~20

Chromistan ‘fungi’ (species previously included in the fungi)

Phylum	World Kirk et al. (2008)	Australia (May pers. comm.163)
Hyphochytriomycota	24	1
Labyrinthista	56164	0
Oomycota (water moulds and downy mildews)	956	73
Incertae Sedis	3	0
TOTAL	1 039	74

Viruses

The main problem in estimating the number of species of viruses is knowing just what constitutes a species in the group. In general, virus species are taken as being a collection of isolates with similar characteristics (ICTV 2002). There are many more virus names than there are ‘species’. There are about 2 000–2 500 species currently recognised by the ICTV, but there are more than 40 000 to 50 000 recorded virus names. Most publications do not differentiate between virus species and virus names (Büchen-Osmond pers. comm.¹⁶⁵). A full list of virus species can be found at http://www.ictvonline.org/virusTaxonomy.asp?version=2008. Many viruses occur in the marine areas of the world, but very few of these are as yet specified (Büchen-Osmond pers. comm.¹⁶⁵).

Estimates for the number of described species of viruses range from about 2 000 (Mayo et al. 2005) through 2 085 (ICTV 2008), 4 000 (Hawksworth and Kalin-Arroyo 1995) to 5 000 (Anon. 1994), with estimates of the total number at about 400 000 (varying from 50 000 to 1 million) (Hawksworth and Kalin-Arroyo 1995). I have accepted the official numbers from the International Committee on the Taxonomy of Viruses (ICTV 2008).

The only figure I have been able to find for Australia is a list of 178 plant viruses (Büchen-Osmond 1988). I have not come across a similar list for animal viruses so, extrapolating, one obtains a figure of about 400 species in total. Büchen-Osmond (pers. comm.¹⁶⁵) suggests that 10–20% of the total would occur in Australia at one time or another, with less than 5% Australia/Australasia specific. Those figures suggest about 200–400 Australian species with somewhat less than 50% of those endemic. These figures are very inaccurate and should not be relied upon.

There are no species of virus listed as threatened.

World Described/ Accepted minimum		World Described/ Accepted maximum		World Described/ Accepted		World Estimate		Australia Described/ Accepted		Australia Percentage		Australia Estimate		Australia Endemic		World Threatened 166
2 000		5 000		2 085		400 000		200–400		9.6–19.2%		unknown		40–50%		–

Protoctista (mainly Protozoa—others included under fungi, algae, Chromista, etc)

The main problem in estimating numbers of Protoctista is in identifying the inter-relationship between different treatments—see following table. There is considerable overlap between what some authors include under Protoctista and what others include as algae, fungi or Chromista. Trying to sort out relationships between the treatments of different authors has not been easy, but the following table is used to enable comparisons with the previous report. For the summary, I have used the data from this table along with data from a number of other sources.

The order of arrangement in the summary table below is to allow for comparisons only and is not meant to imply a taxonomic classification. A lot more work needs to be done to determine accurate numbers for the Protoctista, and the numbers given here are very rough and not to be relied upon. Estimates for the number of Protoctista range from >20 000 (Anon. 1994) through 30 800 (Tangley 1997) to 34 000 (Adl et al. 2007), but these often depend on what groups are included or excluded.

Since the previous report a paper has been published that gives some detailed figures for the protists (Adl et al. 2007), and I have relied heavily (but not exclusively) on the figures given therein for this report. The Dictionary of the Fungi (10^th edition) (Kirk et al. 2008) includes 1 165 Protoctista that were previously included as fungi.

The following table has beeen created from information in Corliss (2000), Groombridge and Jenkins (2002), Brusca and Brusca (2003), and Adl et al. (2007). Groombridge and Jenkins (2002) estimated that there are 80 000 described Protoctista with an estimated total of 600 000 species, however these figures include non-protoctistan taxa such as the diatoms, Chlorophyta, and some fungal groups.

Figures for the number of Australian species have been hard to find, however there are estimates for the total number of species in Australia of 65 000 (Saunders et al. 1996) and 80 000 (ACIL Consulting 2002). See Scott and Marchant (2005) for information on Antarctic marine protists. Patterson (pers. comm.¹⁶⁷) prepared a list of known species and collections for Australia prior to 2005. I have used that unpublished list to determine some of the numbers in the table below, but again, I have found difficulties in fitting the numbers from various sources into the different classifications. It is also obvious that the list contains a number of nomenclatural synonyms and orthographic variants that have not been combined. With the Patterson list there are many undescribed species, and it is clear that the list is far from complete for some groups. It is, however, a good starting point. May (pers. comm.¹⁶⁸) reports that there are 192 Australian species of fungoid protoctista (predominantly Mycetozoa, and a few Plasmidiophorales).

Names as used by					Numbers
Groombridge and Jenkins (2002)	Corliss (2000) (except for species included under Fungi, Algae or Chromista)		Brusca and Brusca (2003)		Groombridge and Jenkins (2002)		Corliss (2000)		Brusca and Brusca (2003)		Adl et al. (2007) (estimates in brackets) See other species under Algae169
Archaeoprotista (Amitochondriates)	Archamoebae (Karyoblastea)		Diplomonadida		accepted?		10		~100		–
Discomitochondria (flagellates, zoomastigates)	Neomonada		(under Diplomonadida)		accepted?		30		–		120 (300)170
Rhizopoda (amastigote amoebae and cellular slime moulds)	Rhizopoda (Amaeobozoa)		Rhizopoda (amoebas)		~200		5 000		~200		>3 006 (~13–23 000)
Myxomycota (Plasmodial slime moulds)	Mycetozoa		Excluded (fungi?)		~500		900		–		Peronosporomycetes 676 (103–104), Mesomycetozoa 47 (thousands)
Granuloreticulosa (Foraminifera and reticulomyxids)	Foraminifera (Granuloreticulosa)		Granuloreticulosa		~4 000		~5 000		~40 000 (incl. many fossils)		>10 000 (15 000)
Xenophyophora (Xenophyophores)	(under Foraminifera)		(under Granuloreticulosa)		42		–		–		–
(under Actinopoda)	Heliozoa		(under Actinopoda)		–		~4 000		–		–
Actinopoda (Radiolarians)	Radiozoa (Radiolaria)		Actinopoda (incl. Polycistina = Radiolaria, Phaeodaria, Heliozoa, Acantharia)		~4 000		1 700–4 000		~4 240		Rhizaria171 (excl. Foraminifera) 1 556–1 876 (thousands)
	Percolozoa		Excluded (fungi?)		–		100		–		–
	Euglenozoa		Euglenida		–		1 600		1 600		–
	(under Euglenozoa)		Kinetoplastida (trypanosomes)		–		–		600		–
					–		–		–		Excavata (except Parabasala)172 1 852 (2 720)
Dinomastigota (Dinoflagellates)	Dinozoa		Dinoflagellata		~4 000		~2 000		4 000		2 000 (
	Metamonada		(under Dinoflagellata)				300		–
	Parabasala		Parabasilida (Trihomonads and Hypermastigotes)				400		~300		466 (500)
Apicomplexa (Sporozoa)	Apicomplexa		Apicomplexa		~5 000		~5 000		~5 000		6 000 (1.2–10 million)
Haplospora	(under Apicomplexa)				33
Plasmodiophora	(under Apicomplexa)				29
Paramyxa	(under Apicomplexa)				6
Ciliophora (Ciliates)	Ciliophora		Ciliophora		~10 000		7 800		12 000		3 500 (30 000)

Summary Table¹⁷³

	Other names and inclusions	World Described/ Accepted	World Estimate	Australia Described/ Accepted	Australia Percentage	Australia Estimate	Australia Endemic
Amoebozoa (incl. cellular slime moulds, excl. fungoid protists)		~3 006	13 000–23 000	~305	10.1%	–	–
Apicomplexa	(parasitic protists)	~5 000	>1 000 000	unknown	unknown	–	–
Ciliata	(protists with cilia)	~4 000	~30 000	151174	3.8%	–	–
Flagellata	(protists with flagella)	~2 200	~3 300	675	25.9%	–	–
Foraminifera	(foraminiferans incl. Radiolaria	>13 500	>18 000	>23	0.2%	–	–
Fungoid protists	Mycetozoa, Myxomycota, Plasmodiophoromycota	1 165	thousands	192	16.5%	–	–
TOTAL		~28 871	>1 000 000	>1 346	4.7%	~65 000	unknown

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