A paper published online today in volume 29 of the journal Nuytsia, provides a dichotomous identification key for 93 species currently recognised in Western Australia. Check it out: A key to Ptilotus (Amaranthaceae) in Western Australia.
A new species of Ptilotus (Amaranthaceae) has recently been described and name Ptilotus unguiculatus T.Hammer. The species is known from a collection in 1970 on Edaggee Station, SSE of Carnarvon, Western Australia.
The species is an annual herb with conspicuously clawed whitish-green sepals, for which it is named unguiculatus (‘having claws’).
Hammer, T.A. 2018. The Ptilotus murrayi species group: synonymisation of P. petiolatus under P. murrayi and description of the new Western Australian species P. unguiculatus (Amaranthaceae). Swainsona 31(6): 93–100.
Ptilotus angustifolius (Benl) T.Hammer is a rare species of Ptilotus (Amaranthaceae) from South Australia (see below map). It has recently been erected as a species from P. nobilis subsp. angustifolius (Benl) Lally & W.R.Barker in Hammer et al. (2018). It is a long-lived rounded shrub or perennial herb with above ground stems becoming basally woody (i.e. a subshrub).
Hammer TA, Macintyre PD, Nge FJ, Davis RW, Mucina L & Thiele KR (2018) The noble and the exalted: a multidisciplinary approach to resolving a taxonomic controversy within Ptilotus (Amaranthaceae). Australian Systematic Botany 31(3), 262–280. https://doi.org/10.1071/SB17062
Photos from our new study on the Ptilotus nobilis species group are on the cover of Australian Systematic Botany volume 31, issue 3. On pages 262–280, you can find our study, The noble and the exalted: a multidisciplinary approach to resolving a taxonomic controversy in Ptilotus (Amaranthaceae).
A new species of Ptilotus (Amaranthaceae) has been described in Volume 29 of Nuytsia. The new species, Ptilotus yapukaratja R.W.Davis & T.Hammer, is a shrub with succulent leaves and pink flowers (pictured) that occurs near Lorna Glen Station (Matuwa) in the Gascoyne bioregion of Western Australia. The specific epithet was proposed by the Elders from the Tarlka Matuwa Piarku Aboriginal Corporation, the traditional custodians of the Matuwa Kurrara Kurrara Indigenous Protected Area and is derived from their words yapu (rock) and karatja (belonging to), referring to the rocky habitat on which it is found. The species is rare and listed as Priority One under Conservation Codes for Western Australian Flora. Further information can be found in the publication:
Davis, R.W. & Hammer, T.A. (2018) Ptilotus yapukaratja (Amaranthaceae), a new and rare species from the Gascoyne bioregion of Western Australia. Nuytsia 29: 157–160. [pdf]
A new and rare species, Ptilotus actinocladus T.Hammer & R.W.Davis, has been recently published in volume 29 of the journal Nuytsia (Hammer & Davis, 2018). The new species is endemic to the Gascoyne bioregion of Western Australia and known from several collections, mostly around Doolgunna Station.
Specimens currently within P. actinocladus were previously assigned to P. pseudohelipteroides Benl, constituting the only specimens of this species from Western Australia. The type of P. pseudohelipteroides is from Queensland, with the typical variety of this species occurring in the Northern Territory, Queensland and South Australia. Ptilotus pseudohelipteroides was described by Gerhard Benl (1959), based on the variety Trichinium helipteroides F.Muell. var. minor J.M.Black described by John M. Black (1924) and latter the combination made within Ptilotus by Hansjörg Eichler (as P. helipteroides var. minor). Benl separated P. pseudohelipteroides from P. helipteroides (F.Muell.) F.Muell. based on it varying in floral and vegetative characters.
When examining the specimens from Western Australia for the identification key to the Ptilotus (available on KeyBase), it was clear that these were different from P. pseudohelipteroides. The morphological variation and geographical disjunction between the two entities clearly showed that the specimens from Western Australia deserve to be placed within its own species. The new species does overlap with P. helipteroides, but is also morhologically distinct from that species in multiple floral and vegetative characters, including the habit, leaf and stem indumentum, and size of the floral parts (which are more similar to P. pseudohelipteroides). The specific epithet of the new species refers to the radiating (actino-) stems (cladus) that are prostrate and characteristic of this species. Please feel free to read it in more detail on FloraBase, at https://florabase.dpaw.wa.gov.au/nuytsia/article/877.
- Benl, G. (1959). New species and varieties of Ptilotus R.Br. (Amaranthaceae). Muelleria 1(2): 105–107.
- Black, J.M. (1924). Casuarinaceae – Euphorbiaceae. Flora of South Australia 2: 212.
- Eichler, Hj. (1965). Supplement to J.M.Black’s Flora of South Australia (Second Edition, 1943-1957): 130.
- Hammer, T.A. & Davis, R.W. (2018). Ptilotus actinocladus (Amaranthaceae), a new and rare species from the Gascoyne bioregion, Western Australia. Nuytsia 29: 145–149. (pdf)
Ptilotus helipteroides (F.Muell.) F.Muell., commonly called ‘hairy mulla mulla’, was described by Ferdinand von Mueller in Fragmenta Phytographiae Australiae (1862) as Trichinium helipteroides F.Muell. The type specimen was collected from near Nichol Bay, present-day Karratha, Western Australia. It is a widespread small herb with papery pink flowers, that can be seen to flower en masse in many of the drier parts of Western Australia and central Australia. The specific epithet refers to its similarity with the paper daisy genus Helipterum DC. (Asteraceae), which can also have papery pink flowers and can form large stands of flowering displays. Many of the species of Helipterum have be transferred to other genera (e.g. Rhodanthe Lindl.). This choice of a specific epithet is perhaps unfortunate, as I do not think that the two plants share a close affinity.
I suppose that the common name ‘hairy mulla mulla’ probably refers to the hairs that cover the leaves and stems of the species, apart from other ‘mulla mulla’ species (like Ptilotus exaltatus Nees, ‘tall mulla mulla’), which tend to be glabrous on the stem and leaves. Since many Ptilotus spp. have a persistent indumentum on the vegetative surface, I think this common name can potentially lead to confusion, as common names tend to do.
Ptilotus helipteroides has an interesting floral morphology. It has 4 fertile stamens opposite to the lower sepals (or ‘tepals’) and one staminode opposite the upper sepal. This staminode is coloured orange at its base, and it is flanked by two staminal cup appendages that are also coloured orange and decorated with coloured fringed hairs. Smaller, uncoloured staminal cup appendages alternate with the stamens. These features no doubt serve as signals for pollinators to land in a specific orientation, probably with insects’ head orientated towards to the staminode and probing the staminal cup for nectar. The stamens are curved and orientated to place the pollen on the under section of the pollinator. The flowers appear to be protandrous. A similar pollination mechanism has been observed in Ptilotus gaudichaudii (Steud.) J.M.Black, though the arrangement of the stamens in relation to the style and colours of the flowers varies between these species (Hammer et al., 2018). The P. gaudichaudii species group (also including P. modestus T.Hammer and P. eremita (S.Moore) T.Hammer & R.W.Davis) has been found to be closely related to P. helipteroides on recent molecular phylogenies of the genus (e.g. Hammer et al., 2015). Also closely related to P. helipteroides is P. pseudohelipteroides Benl.
- Hammer, T., Davis, R. & Thiele, K. (2015). A molecular framework phylogeny for Ptilotus (Amaranthaceae): Evidence for the rapid diversification of an arid Australian genus. Taxon 64(2): 272–285. http://dx.doi.org/10.12705/642.6
- Hammer, T.A., Davis, R.W. & Thiele, K.R. (2018). The showy and the shy: reinstatement of two species from Ptilotus gaudichaudii (Amaranthaceae). Australian Systematic Botany 31: 1–7. https://doi.org/10.1071/SB17026
- Mueller, F.J.H von (1862). Fragmenta Phytographiae Australiae. Vol. 3. (Government Printer: Melbourne)