Poikilospermum
Poikilospermum suaveolens
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Rosales
Family:	Urticaceae
Tribe:	Urticeae
Genus:	Poikilospermum Zipp. ex Miq.
Species
Between 4 & 41, see text

Poikilospermum is a genus of shrubs or tall woody climbers, consisting of at least 33 accepted species. The plants are found from India and China (Yunnan), the Sino-Himalayan region to Sulawesi and Jawa in Indonesia. Some of the plants are used by people.

Common names in the genus include the Chinese 锥头麻属 (zhui tou ma shu) and 陈家瑞 (chen jiarui or chen chia-jui),^[1] and the Khmer krâpë rô.^[2]

The classification of the genus was dynamic and the in past was linked to the status of the family Cecropiaceae. At present, consensus places it in the family Urticaceae.^[3][4][5] One recent phylogenetic study placed it in a clade with Urtica, though two slightly older studies placed it as a sister clade to the Cecropieae (the former Cecropiaceae s. str.) and Urticaeae (Urticaceae s. antiq.).^[5] Older, nonphylogenetic, work placed the genus in Cecropiaceae, a family regarded as intermediate between Urticeae and Moraceae^[1]

Alexander Zippelius (1797-1828) is given authorship of the genus, publishing in Annales Musei Botanici Lugduno-Batavi (Amsterdam), 1: 203, in 1864. His work superseded that of Friedrich Anton Wilhelm Miquel (1811-1871). In 1978, Berg placed it in Cecropiaceae. Most recent work has been by Datwyler & Weiblen (2004), Zerega et al. (2005), and Hadiah et al. (2008) place the genus in Urticaceae.

Members of Poikilospermum are shrubs or tall woody climbers (also known as lianas).^[1] The petiolate leaves are alternate; their stipules are often caducous, intrapetiolar, connate, and leathery; their veins are often prominently pinnate; cystoliths occur adaxially in circular groups, abaxially along veins, either punctiform or linear. The inflorescences are solitary and axillary dichotomously branched cymes, they are unisexual (the plants are dioecious). The glomerules are capitate and either on swollen peduncular receptacles (in P. subgen. Ligulistigma, continental Asia group), in agglomerations, or are free (in P. subgen. Poikilospermum, E Malaysia group). The male flowers are with 2-4 perianth lobes, free or slightly connate; there are two to four stamens, the filaments are straight (in P. subgen. Ligulistigma) or inflexed; a rudimentary ovary is present. The female flowers have four perianth lobes, and are clavate-tubular and decussate-imbricate. The ovary in this genus is enclosed, with a short style, a capitate or ligulate (in P. subgen. Ligulistigma) stigma; the ovule is orthotropous. The seeds have little or no endosperm. The cotyledons are ovate.

Plants of the genus occur naturally from India across to Southeast Asia, China and Indonesia.^[3][1] Countries and regions in which plants of the genus grow include: Indonesia (Maluku, Sulawesi, Kalimantan, Jawa, Sumatera); Philippines; Malaysia (Sabah, Sarawak, Peninsular Malaysia); Thailand; Cambodia; Vietnam; Zhōngguó/China (South-central); Laos; Myanmar; India (including Nicobar Islands, Andaman Islands, Assam); Bangladesh; Tibet; East Himalaya. The genus has also been introduced to Jamaica. In China there are 3 species. Species often have high moisture requirement, occurring in Monsoon forests and rain forests, often near streams or other we places, at altitudes ranging from 500m to 1800m. In Cambodia P. suaveolens grows in the undergrowth of dense forests.^[2]

One species is used to produce ties (as in to tie things together).^[2]

These species are accepted, as of February 2021:

Wikispecies has information related to Poikilospermum.