A recent trip to Western Australia’s Mid West region

New Ptilotus species from the Gascoyne

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]

Ptilotus actinocladus

Ptilotus actinocladus
The new species, Ptilotus actinocladus T.Hammer & R.W.Davis. Photo by G. Byne.

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.

Ptilotus pseudohelipteroides
Ptilotus pseudohelipteroides Benl in South Australia. Photo by T. Hammer.

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.

Ptilotus actinocladus map
Map the distribution of Ptilotus actinocladus (triangles), P. helipteroides (vertical shading) and P. pseudohelipteroides (horizontal shading).

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)

Royal mulla mulla

Royal mulla mulla
Ptilotus rotundifolius near Tom Price in the Pilbara, Western Australia. Photo by T. Hammer.

One of my favorite species is Ptilotus rotundifolius (F.Muell.) F.Muell, the royal mulla mulla, which is found in the Pilbara, Gascoyne and Murchison bioregions of Western Australia. This long-lived shrub can reach > 2 m high. The specific epithet (rotundifolius) refers to the large and broad leaves (> 3 cm wide), which are covered in the a dense, velvety indumentum. These leaves make it one of the most cuddly Ptilotus species. The species was originally described by Mueller (1862) in the genus Trichinium, which was later included within Ptilotus by Mueller (1868).

Ptilotus rotundifolius
Ptilotus rotundifolius on a hill with exposed banded iron formation rocks near Cue, Western Australia. Photo by T. Hammer.

Ptilotus rotundifolius is closely related to P. marduguru Benl (Benl, 1980; Hammer et al., 2015), a rare species from Southesk Tablelands in the Great Sandy Desert, Western Australia. These two species do not overlap in distribution and can be easily differentiated based on P. rotundifolius having pink flowers and spiciform inflorescences > 30 mm wide. Ptilotus marduguru has cream-green flowers and inflorescences that are < 21 mm wide. Like P. marduguru and other closely related species (e.g. P. auriculifolius (A.Cunn. ex Moq.) F.Muell.), P. rotundifolius has 5 fertile stamens and a centrally placed style on the ovary. These characters were found to be associated with the basal clades of Ptilotus (Hammer et al., 2015) and are probably pleisiomorphic within the genus.

Ptilotus rotundifolius
An open flower of Ptilotus rotundifolius (F.Muell.) F.Muell. Photo by T. Hammer

The pink flowers and densely wooly indumentum on the interior surface of the sepals (sometimes “tepals”) of P. rotundifolius are shared with more distantly related species such as P. drummondii (Moq.) F.Muell., P. exaltatus Nees and Ptilotus manglesii (Lindl.) F.Muell., all of which have been observed to be pollinated by native Australian bees (pers. obs.). These characters may be indicative of a bee pollination syndrome in the genus. The close relatives to P. rotundifolius that have green flowers (i.e. P. marduguru and P. auriculifolius) may be pollinated by moths like more distantly related green-flowering species, such as P. macrocephalus (R.Br.) Poir. and P. polystachyus (Gaudich.) F.Muell. (pers. obs.). Shifts in pollination syndromes from bees to moths (or vice versa) may be an important driver of speciation throughout the genus.

  • Benl, G. (1980). Five new taxa of Ptilotus (Amaranthaceae) from Western Australia. Nuytsia 3: 157-161. https://florabase.dpaw.wa.gov.au/nuytsia/article/53
  • 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
  • Mueller, F.J.H von (1862). Fragmenta Phytographiae Australiae. Vol. 3, p. 122. (Government Printer: Melbourne)
  • Mueller, F.J.H von (1868). Fragmenta Phytographiae Australiae. Vol. 6, p. 230. (Government Printer: Melbourne)

Pom poms

Ptilotus manglesii habit
The habit of Ptilotus manglesii near Bindoon in Western Australia. Photo by T. Hammer.

Ptilotus manglesii (Lindl.) F.Muell. (commonly called mulla mulla or pom poms) is a perennial herb endemic to the south-west of Western Australia and common in the hills around Perth, typically occurring in Eucalyptus woodlands and forests. It was described as Trichinium manglesii by John Lindley in Edwards’ botanical register in 1839 from “Swan River Colony” (probably near present-day Perth). It was later transferred to Ptilotus R.Br. by Mueller (1868). The species was named for Captain James Mangles of the Royal Navy, who was interested in botany and horticulture in colonial Western Australia and had collected plant specimens for Lindley.

Ptilotus manglesii
An inflorescence of Ptilotus manglesii (Lindl.) F.Muell. Photo by T. Hammer

Ptilotus manglesii has been found to be closely related to P. nobilisP. exaltatus species group on the molecular phylogeny of the genus (Hammer et al., 2015). Ptilotus exaltatus overlaps slightly in distribution with P. manglesii around Geraldton, Western Australia. It can be easily distinguished from P. exaltatus by its perennial, decumbent habit, as well as multiple floral characters. Two phrase-names at the Western Australian Herbarium, Ptilotus sp. Beaufort River (G.J. Keighery 16554) and Ptilotus sp. Porongurup (R. Davis 10805), that are morphologically similar to P. manglesii are currently being investigated as putative new species. More to come about these two!

  • 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
  • Mueller, F.J.H von (1868). Fragmenta Phytographiae Australiae. Vol. 6, p. 230. (Government Printer: Melbourne) http://dx.doi.org/10.5962/bhl.title.287

Ptilotus benlii

Ptilotus benlii
Flowering inflorescences of Ptilotus benlii. Photo by R. Davis.

Ptilotus benlii R.W.Davis & T.Hammer was recently described in the journal Nuytsia as a new species for Western Australia (Davis & Hammer, 2017). It is a perennial herb found from south of Kalbarri to north of Merridin, WA.

Ptilotus benlii is closely related to P. calostachyus F.Muell., P. drummondii (Moq.) F.Muell., P. aphyllus Benl and P. schwartzii (F.Muell.) Tate. It shares the character with these species of possessing staminal cup appendages, but can be easily differentiated by its larger, green-white flowering spikes and bright pink filaments and stamens. Ptilotus benlii is also quite close to the southwestern species P. esquamatus (Benth.) F.Muell., with which it differs in that the latter lacks staminal cup appendages and has much smaller inflorescences of pinkish flowers and a decumbent habit.

Ptilotus benlii
The habit of Ptilotus benlii. Photo by R. Davis.

The species was named in honour of German botanist Gerhard Benl (1910–2001), who contributed significantly to the taxonomy of Ptilotus throughout his career, naming upwards of 30 species and various infraspecific taxa.

Davis, R.W. & Hammer, T.A. (2017). Ptilotus benlii (Amaranthaceae), a new species from Western Australia. Nuytsia 28: 299–302. https://florabase.dpaw.wa.gov.au/nuytsia/article/853