Sabicea floribunda var. paludosa O. Lachenaud, Zemagho & Sonké, 2020

Lachenaud, Olivier, Zemagho, Lise & Sonké, Bonaventure, 2020, A synopsis of the Sabicea floribunda group (Rubiaceae) from Central Africa, including three new species, Candollea 75 (1), pp. 115-143 : 129-130

publication ID

https://doi.org/ 10.15553/c2020v751a12

DOI

https://doi.org/10.5281/zenodo.6315759

persistent identifier

https://treatment.plazi.org/id/5F1C9F17-8C1C-4E1A-4247-F02480255032

treatment provided by

Carolina

scientific name

Sabicea floribunda var. paludosa O. Lachenaud, Zemagho & Sonké
status

var. nov.

3c. Sabicea floribunda var. paludosa O. Lachenaud, Zemagho & Sonké , var. nov.

Holotypus: DEMOCRATIC REPUBLIC OF CONGO. Tshopo: Lilanda ( Yangambi ), 15.VIII.1940, fl., Germain 449 ( BR!; isotype: K!).

Ab alteribus varietatibus differt bracteis ± obovatis utrinque dense pubescentibus (nec orbicularibus, ovatis vel late ellipticis, glabris vel pilis sparsis munitis).

Etymology. – The epithet paludosa refers to the fact that this taxon is most commonly found in swamp and riverine forests, while other varieties usually grow on drained soils.

Distribution, ecology and phenology. – This taxon occurs in northeastern Gabon, and in D. R. Congo where it is found mostly in the central depression of the Congo basin (“cuvette congolaise”) with isolated records further east (Kivu) and south (near the border with Angola) ( Fig. 8 View Fig ). Its range closely approaches that of var. anisostegia in both Gabon and D. R. Congo. It grows mostly in swamp and riverine forest, but apparently also in secondary forest regrowth on drained soils, 350–1000 m in elevation.

Flowers have been recorded in January, from April to June and from August to October; fruits from April to October.

Conservation status. – The extent of occurrence ( EOO) of S. floribunda var. paludosa is calculated to be 759,404 km ², well above the limit for “Vulnerable” status under subcriterion B 1. Its area of occupancy is estimated to be 64 km ², which falls within the limit for “Endangered” status under subcriterion B 2, but is an obvious underestimation, given the low collecting density in most of its range. The taxon occurs in eastern Gabon and the Democratic Republic of Congo, and is known from 21 specimens representing 15 subpopulations, one of which occurs in a protected area (Kahuzi-Biega National Park in D. R. Congo). It is found in swamp forest and secondary forest regrowth, and appears to be not rare in its range. Given its ecology and wide distribution there is no evidence of a particular threat, and it is here assessed as Least Concern [LC] using the IUCN Red List Categories and Criteria ( IUCN, 2012).

Notes. – This taxon differs from other varieties by its more or less obovate and densely pubescent bracts (vs. orbicular, ovate or broadly elliptic, with indumentum sparse or absent) which are also usually narrower in proportion – hence a similarity with S. segregata , but that species does not occur in its range. In all other characters, especially leaves and indumentum, it comes very close to var. floribunda .

Paratypi. – DEMOCRATIC REPUBLIC OF CONGO. Bandundu : Iküma , 13.X.1948, fl., Jans 807 ( BR). Equateur : Ikelemba , VI.1934, fl., Dubois 423 ( BR); rte Bikoro-Inongo, km 27, 17.X.1957 , imm.fr., Evrard 2674 ( BR); rte Flandria-Makako (territoire Ingende ), 9.IV.1959, fl., Evrard 6054 ( BR); Bondombe, 9.IX.1942, buds, Hulstaert 843 ( BR); Lac Tumba-I.R.S.A.C. Mabali , 20.VI.1958, imm.fr., Thonet 221 ( BR, K). Kwango: entre Popokabaka et Kimabaka , près rivière Pumbu , 18.IV.1959, fl., Pauwels 2495 ( BR, P). Kwilu: vallée de la Djuma , VII.1902, imm.fr., Gentil s.n. ( BR); région de Bampumu, X.1922, fl., Vanderyst 12481 ( BR). Sud-Kivu: Kiaselela , territoire Shabunda , 19.IV.1959, imm.fr., A. Léonard 3900 ( BR, P). Tshopo: Opala , 15.VI.1949, imm.fr., Germain 5116 ( BR, WAG); Yabahondo ( rive gauche du Lomami ), 15.X.1952, fl. & imm.fr., Germain 8116 ( BR); Yangambi , 3.VI.1958, imm.fr., A. Léonard 759 ( BR, K); env. de Kisangani , à 3 km à l’E de Kabondo, 24.X.1977, buds, Lisowski 47453 ( BR, K); Kisangani, Kabondo , 6.V.1979, fl. (fallen), Lisowski 52401 ( BR, K); 20 km à l’W de Yangambi, 27.X.1938, fl., J. Louis 12110 ( BR). Tshuapa: Befale , IX.1934, imm.fr., Dubois 767 ( BR); Befale-Tolongote , 5.VI.1958, fl., Evrard 4185 ( BR, K, WAG). Sine loco: sine loco, s.d., fl., Pauwels 660 ( BR).

GABON. Ogooué-Ivindo: 10 km on road Malassa to Madouma, 8.I.2001, fl., Wieringa et al. 4028 ( LBV, WAG).

WAG

WAG

LBV

LBV

BR

Embrapa Agrobiology Diazothrophic Microbial Culture Collection

K

Royal Botanic Gardens

R

Departamento de Geologia, Universidad de Chile

B

Botanischer Garten und Botanisches Museum Berlin-Dahlem, Zentraleinrichtung der Freien Universitaet

P

Museum National d' Histoire Naturelle, Paris (MNHN) - Vascular Plants

WAG

Wageningen University

LBV

CENAREST

Kingdom

Plantae

Phylum

Tracheophyta

Class

Magnoliopsida

Order

Gentianales

Family

Rubiaceae

Genus

Sabicea