{{Short description|Genus of plant in the family Crassulaceae}} {{Speciesbox | status = CR | status_system = IUCN3.1 | status_ref = <ref name=IUCN>{{cite iucn |last1=Rabarimanarivo |first1=M. |year=2024 |title=''Perrierosedum madagascariense'' |volume=2024 |article-number=e.T216490147A216492956 |access-date=3 August 2024}}</ref> | genus = Perrierosedum | parent_authority = (A.Berger) H.Ohba | species = madagascariense | authority = (H.Perrier) H.Ohba | synonyms = *''Sedum madagascariense'' <small>H.Perrier</small> | synonyms_ref = <ref name=POWO>{{cite web |title=''Perrierosedum madagascariense'' (H.Perrier) H.Ohba |url=https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A274683-1 |website=Plants of the World Online |publisher=Royal Botanic Gardens, Kew |access-date=3 August 2024}}</ref> }}
'''''Perrierosedum''''' is a genus of succulent plant in the family Crassulaceae containing only one species, '''''Perrierosedum madagascariense'''''. It is a critically endangered species endemic to Madagascar.<ref name=POWO/>
==Taxonomy and history== ''Sedum madagascariense'' was described by French botanist Joseph Marie Henry Alfred Perrier de la Bâthie in 1923. ''S. madagascariense'' was placed in ''Sedum'' section ''Perrierosedum'', named in honour of Perrier de la Bâthie, in 1930 by Alwin Berger.<ref>{{cite book |last1=Burkhardt |first1=Lotte |title=Verzeichnis eponymischer Pflanzennamen – Erweiterte Edition |trans-title=Index of Eponymic Plant Names – Extended Edition |publisher=Botanic Garden and Botanical Museum Berlin, Freie Universität Berlin |year=2018 |volume=2 |page=P-10 |isbn=978-3-946292-26-5 |url=https://www.bgbm.org/sites/default/files/verzeichnis_eponymischer_pflanzennamen_2018_teil_2.pdf |language=German |location=Berlin |doi=10.3372/epolist2018 |access-date=4 August 2024}}</ref> ''Sedum'' sect. ''Perrierosedum'' would later be elevated to genus by Japanese botanist Hideaki Ohba in 1978, re-designating the species ''Perrierosedum madagascariense''.<ref name=BD2005>{{cite journal |last1=Descoings |first1=Bernard |author-link1=Bernard Descoings |year=2005 |title=Le genre ''Perrierosedum'' (Berger) H. Ohba (Crassulaceae) à Madagascar |journal=Acta Botanica Gallica |volume=152 |issue=3 |pages=289–292 |doi=10.1080/12538078.2005.10515491|bibcode=2005AcBG..152..289D }}</ref>
This species is known as {{lang|mg|maroatody}} in Malagasy.<ref name=IUCN/><ref name=BD2005/>
==Distribution and habitat== ''P. madagascariense'' is known only from Andringitra Massif in the Haute Matsiatra and Ihorombe regions of south-central Madagascar. It grows on rocky outcrops at altitudes of {{cvt|1600|m}} to {{cvt|2659|m}}.<ref name=IUCN/>
==Description== ''P. madagascariense'' is a small perennial shrub growing {{cvt|50-80|cm}} tall. The branches are hairless and quadrangular. The fleshy leaves are sessile, borne opposite one another, measuring {{cvt|2.5-5|cm}} by {{cvt|1.5-2.5|cm}} with finely toothed margins. The inflorescence is a terminal corymbose cyme bearing three to ten flowers. The flowers measure approximately {{cvt|10|mm}} across and are hexamerous or, rarely, pentamerous. The petals are white with a red to orange tint and purple veins.<ref name=BD2005/><ref name=Handbook>{{cite book |editor-last1=Eggli |editor-first1=Urs |year=2003 |chapter=Crassulaceae |title=Illustrated Handbook of Succulent Plants: Crassulaceae |publisher=Springer |page=196 |doi=10.1007/978-3-642-55874-0 |isbn=978-3-642-62629-6 }}</ref>
==Conservation status== ''P. madagascariense'' is listed as critically endangered by the International Union for the Conservation of Nature under criterion B2ab(iii), based on its small area of occupancy and the decline of its habitat. It is known only from a single location within Andringitra National Park, and the size of the population is unknown. Despite occurring within a protected area, it is threatened by wildfires, grazing, and human disturbance from hikers and rock climbers.<ref name=IUCN/> This species has been planted at the Botanical and Zoological Garden of Tsimbazaza in Antananarivo, Madagascar.<ref name=IUCN/>
==References== {{Reflist}}
{{Taxonbar|from1=Q15899910|from2=Q149913}}
Category:Crassulaceae Category:Crassulaceae genera Category:Monotypic Saxifragales genera Category:Endemic flora of Madagascar Category:Critically endangered flora of Africa Category:Plants described in 1923 Category:Taxa named by Alwin Berger Category:Taxa named by Joseph Marie Henry Alfred Perrier de la Bâthie