Bromus lithobius is a species of brome grass known by the common name Chilean brome in English.[1][2] It is native to Chile and Argentina, but is introduced in Australia and New Zealand.[2]
| Bromus lithobius | |
|---|---|
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Embryophytes |
| Clade: | Tracheophytes |
| Clade: | Spermatophytes |
| Clade: | Angiosperms |
| Clade: | Monocots |
| Clade: | Commelinids |
| Order: | Poales |
| Family: | Poaceae |
| Subfamily: | Pooideae |
| Genus: | Bromus |
| Species: | B. lithobius |
| Binomial name | |
| Bromus lithobius Trin. | |
It is one of several species in the Bromus catharticus complex within the Bromus section Ceratochloa, all of which are hexaploids with the chromosome count 2n=42.[3][4]
Description
editBromus lithobius is a short, tufted pasture grass with spreading culms. Its culms bare an open panicle inflorescence, 10-20 cm long. Its spikelets are 2-3.5 cm long, with five to seven flowers. Its lemmas are pubescent and usually purple-suffused. The lemmas have a 4-6 mm awn.[2]
Bromus lithobius is part of Bromus section Ceratochloa, which are separated from other Bromus sections by their strongly keeled (folded, like the keel of a boat)[5] lemmas, which make the spikelets laterally-compressed.[6]
It can be separated from other members of the section Ceratochloa by the longer awns and distinctly pubescent hairs on its lemmas.
- From Bromus catharticus, B. lithobius has a more compact seed-head with upright or spreading branches. It has pubescent hairs, rather than being glabrous or scabrid.
- From B. cebadilla, B. lithobius has a longer lower glume (6-7.5mm rather than 4-4.5mm), is hairier, and is evenly green rather than green and yellow.[7][8]
Distribution
editBromus lithobius is native to Chile and Argentina, but introduced to New Zealand and Australia.[1][2] In Chile, it is found from the IV to the XI Region, and in Argentina is found in the Andean-Patagonian region, southern Neuquén and northern Río Negro.[9]
In New Zealand, it is found in North Island throughout south of Auckland City; in the South Island it is found in Nelson, Marlborough, and Canterbury.[2]
In Australia, B. lithobius is found in Victoria and Tasmania. It is uncommon in Victoria, with most collections from domestic gardens in the vicinity of Melbourne.[10] In Tasmania it in known only from around Hobart.[11] One specimen listed from New South Wales has more recently been determined as Bromus coloratus.[11]
Habitat
editIn Chile, B. lithobius grows from sea level up to 1,800 metres above sea level in natural grasslands and roadsides.[9] In Australia and New Zealand, B. lithobius is largely associated with pastoral habitats, lawns, and other exotic-dominated habitats.[2][10] In Manawatu, New Zealand, its habitat is described as "edges of lawns and berms, and in urban waste spaces".[12]
Ecology
editBromus lithobius reproduces with either cleistogamous (selfing) or chasmogamous (out-crossing) wind-pollinated flowers.[2] In Australia it flowers from October-January, and in New Zealand from September-February.[11][13] In New Zealand it goes to seed from September-June.[13]
B. lithobius is a host of the bacterion Xanthomonas bromi Vauterin, which causes wilt on species of Bromus.[14]
On Motukahakaha Island in the Hauraki Gulf, it is described as forming dense swards in black backed gull (Larus dominicanus) colonies.[15]
References
edit- 1 2 "Bromus lithobius Trin. | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2026-06-14.
- 1 2 3 4 5 6 7 Connor (2000). "Bromus lithobius Trin".
- ↑ STEBBINS Jr., G. Ledyard (1949). "The Evolutionary Significance of Natural and Artificial Polyploids in the Family Gramineae". Hereditas. 35 (S1): 461–485. doi:10.1111/j.1601-5223.1949.tb03355.x. ISSN 1601-5223.
- ↑ Klos, Joanna; Sliwinska, Elwira; Kula, Adam; Golczyk, Hieronim; Grabowska-Joachimiak, Aleksandra; Ilnicki, Tomasz; Szostek, Krzysztof; Stewart, Alan; Joachimiak, Andrzej J. (2009). "Karyotype and nuclear DNA content of hexa-, octo-, and duodecaploid lines of Bromus subgen. Ceratochloa". Genetics and Molecular Biology. 32: 528–537. doi:10.1590/S1415-47572009005000046. ISSN 1415-4757.
- ↑ "A Grammatical Dictionary of Botanical Latin". www.mobot.org. Retrieved 2025-10-18.
- ↑ "Bromus - FNA". floranorthamerica.org. Retrieved 2025-10-18.
- ↑ "Bromus catharticus". keyserver.lucidcentral.org. Retrieved 2026-06-24.
- ↑ "Bromus L. - Flora of New Zealand Series". floraseries.landcareresearch.co.nz. Archived from the original on 2026-03-06. Retrieved 2026-06-24.
- 1 2 Matthei, Oscar (1961). "The Genus Bromus L. (Poaceae) in Chile". Gayana. 43: 94.
- 1 2 "VicFlora: Bromus lithobius". vicflora.rbg.vic.gov.au. Retrieved 2026-06-24.
- 1 2 3 Atlas of Living Australia. "Profile". profiles.ala.org.au. Archived from the original on 2025-04-06. Retrieved 2026-06-24.
- ↑ Duguid, Prances C. (1990). "Botany of northern Horowhenua lowlands, North Island, New Zealand". New Zealand Journal of Botany. 28 (4): 381–437. doi:10.1080/0028825X.1990.10412326. ISSN 1175-8643.
- 1 2 "Chilean Brome (Bromus lithobius)". iNaturalist. Retrieved 2026-06-24.
- ↑ "National Collection of Plant Pathogenic Bacteria Catalogue". ncppb.fera.co.uk. Retrieved 2026-06-24.
- ↑ De Lange, Peter (1995). "Additions and comments on the flora and fauna of Motukahakaha Island Hauraki Gulf Auckland" (PDF).