Juncus microcephalus

Plate 1 figs. a–h · 6 observations

This species has been photographed under an open licence only 6 times, so some figures below are different views of the same plant, taken on the same day, rather than different individuals. They are usually different parts of it: the leaf, the flower, the bark.

Juncus microcephalus, photographed by Ann Bentley — fig. a Ann Bentley, CC BY 4.0 / 2021-10-17 / obs. 163955268

Juncus microcephalus, photographed by John Steel — fig. b John Steel, CC BY 4.0 / obs. 3218266

Juncus microcephalus, photographed by naturewatchwidow — fig. c naturewatchwidow, CC BY 4.0 / obs. 176106131

Juncus microcephalus, photographed by Khands — fig. d Khands, CC BY 4.0 / obs. 174474195

Juncus microcephalus, photographed by Leon Perrie — fig. e Leon Perrie, CC BY 4.0 / obs. 110894759

Juncus microcephalus, photographed by Joe Potter Butler — fig. h Joe Potter Butler, CC BY 4.0 / obs. 128094634

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

The specimen a real sheet, in a real collection

Herbarium: The New York Botanical Garden
Accession: 382856
Filed as: Juncus microcephalus Kunth
Det. by: H. Balslev 1987-01-01
Collected: G. G. Hatschbach 1983-01-26
Origin: BR
The sheet: View the digitised specimen (CC BY 4.0)

A real pressed plant, in a real collection, under the accession number above. Not an illustration of one. The holding institution does not serve this sheet’s image to third parties, so there is no photograph here. The record is real and the link goes to it. Where we hold no openly licensed sheet for a species this section is simply absent, and where a sheet never recorded who determined it, that field stays empty rather than being filled in. Roughly half of all herbarium sheets never recorded a determiner, which is ordinary.

Native range 24 botanical countries

Native distribution of Juncus microcephalus, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows.

Region	TDWG code	Continent
Argentina Northeast	AGE	SOUTHERN AMERICA
Argentina Northwest	AGW
Argentina South	AGS
Bolivia	BOL
Brazil Northeast	BZE
Brazil Southeast	BZL
Chile Central	CLC
Colombia	CLM
Costa Rica	COS
Ecuador	ECU
Guatemala	GUA
Honduras	HON
Nicaragua	NIC
Panamá	PAN
Paraguay	PAR
Peru	PER
Uruguay	URU
Venezuela	VEN
Mexico Central	MXC	NORTHERN AMERICA
Mexico Gulf	MXG
Mexico Northeast	MXE
Mexico Northwest	MXN
Mexico Southeast	MXT
Mexico Southwest	MXS

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Where it actually grows measured, from 94 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	2.0 °C	7.9 °C	11.6 °C
Warmest month, mean daily high	17.9 °C	23.1 °C	31.2 °C
Annual rainfall	670 mm	1,170 mm	2,160 mm
Rainfall in the driest quarter	35 mm	201 mm	364 mm

It is found where winters are cool but frost is light or absent. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 94 research-grade observations of Juncus microcephalus that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.

Also published as 15 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

Juncus floribundus Kunth
Juncus floribundus Phil.
Juncus involucratus Steud. ex Buchenau
Juncus luzoloxiphium Griseb.
Juncus microcephalus f. conglobatus Barros
Juncus microcephalus var. floribundus (Kunth) Kunth
Juncus microcephalus var. floribundus (Kunth) E.Mey.
Juncus microcephalus var. intermedius E.Mey. ex Schult. & Schult.f.
Juncus microcephalus var. major Schult. & Schult.f.
Juncus microcephalus var. microcephalus
Juncus microcephalus var. typicus Buchenau
Juncus microcephalus var. virens Griseb.
Juncus rudis Kunth
Juncus sellowianus Kunth
Juncus timotensis Barros

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.