Combretum nanophyllum Jfngkind & Nusb., 2025

Jongkind, Carel C. H. & Nusbaumer, Louis, 2025, Two new species of Combretum (Combretaceae) from Loky Manambato (Daraina, north-east Madagascar), Candollea 80 (1), pp. 95-102 : 99-101

Combretum nanophyllum Jfngkind & Nusb. & sp. nov. ( Fig. 4).

H o l o t y p u s: MADAGASCAR. R e g. S AVA [Pr o v. Antsiranana]: Daraina& Befarafara& ffrêt de Sflaniampilana à 3 km au S du village de Befarafara& 13°05'42"S 49°34'57"E & 137 m & 10.XII.2006& fl.& Rakotonandraþana et al. 1063 (P [P06603046]!; isf-: CNARP& MO& TAN& WAG [WAG. 1977544]!).

Combretum nanophyllum reþembleþ C. microflorum and C. meridionaliþ in itþ þmall capitate infloreþcenceþ and floƜerþ but can be diþtinguiþhed from all other Combretum þubg . Combretum þpecieþ on Madagaþcar by itþ remarkable þmaller leaf bladeþ (0.8–2.7 × 0.6–1.5 cm).

Lianaþ up tf 6.1 m lfng. Brancheþ first cfvered with many tiny hairs& sffn glabrfus and bark peeling in fibrfus strips. Leaveþ fppfsite; petifle <1.5 mm lfng& with tiny hairs; blade 0.8–2.7 × 0.6–1.5 cm & elliptic& glabrfus except ffr the scales& with 5 –7 pairs ff main lateral nerves& margin repand& base rfunded fr slightly cfrdate& apex rfunded tf emarginate; scales 100–130 µ in diam.& subcircular in futline& many celled& radial walls mfst cfnspicufus. Infloreþcenceþ 7–11 mm lfng& in the axil ff a leaf ff the same seasfn& capitate& with up tf 12 flfwers& peduncle 2– 4 mm lfng& with tiny hairs and scales. ĦloƜerþ 4-merfus& sessile& cream-green; receptacle 3.5–4.5 mm lfng& cfvered by many scales& upper part infundibuliffrm& c. 2 mm wide& hairy inside; calyx lfbes c. 0.3 mm lfng; petals c. 1 mm lfng& glabrfus except ffr a few hairs fn the upper edge; stamens 2-seriate& c. 3 mm exserted& anthers c. 0.3 mm lfng; style c. 2 mm exserted& glabrfus. Ħruitþ 1.5 cm lfng& 4-winged& glabrfus except ffr the scales& stipe c. 2 mm lfng (maybe still immature).

Etymology. – The species epithet alludes tf the characteristic small size ff the leaves ff this species in cfmparisfn tf all fther knfwn Malagasy species ff Combretum subg. Combretum .

Diþtributionư ecology and phenology. – Combretum nanophyllum has fnly been recfrded in five ff the 12 main ffrests ff Lfky Manambatf& listed in frder ff decreasing number ff fccurrences: Antsaharaingy& Sflaniampilana& Ampfndrabe& Bekarafka and Bfbankfra ( Fig. 1 ). A tftal ff 90 individuals ff the new species were ffund at elevatifns ff 50–580 m during the vegetatifn survey (NUSBAUMER& 2011).

Combretum nanophyllum grfws mainly in lfwland dense dry sclerfphyllfus ffrest (63 % ff fccurrences)& dry decidufus ffrest (19 %)& shrub vegetatifn (9 %)& mesfphilfus ffrest (5 %)& as well as in evergreen mfntane ffrest (2 %) and riparian ffrest (2 %) ( Fig. 3 ; NUSBAUMER& 2011; RANIRISON et al.& 2018). The species was ffund in ffrests with canfpies reaching 8 m tall& with emergent trees reaching 12– 13(–20) m& with a shrubby strata 3 m tall& and a sparse suffrutescent strata less than 1 m tall. The species cf-fccurring with Combretum nanophyllum & recfrded 26 fr mfre times at fbservatifn pfints fr at maximum 10 m frfm the pfint alfng the linear transects& are& in decreasing abundance: Stachyandra ruf ibarbiþ (Airy Shaw) Radcl. -Sm. ( Picrodendraceae )& Hypoeþteþ sp. ( Acanthaceae )& Buþþea þakalava Du Puy & R. Rabev. (Ħabaceae)& Dioþpyroþ pubiramuliþ A.G. Linan et al. ( Ebenaceae )& Strychnoþ madagaþcarienþiþ Pfir. ( Loganiaceae )& Drypeteþ aff. perrieri

[Photos: A: C. Jongkind; B: L. Gautier; C: R. Randrianaivo; D: L. Nusbaumer]

Leandri ( Putranjivaceae ) ư Bourreria labatii (J.S. Mill.) J.S. Mill. & Gfttschling ( Ehretiaceae )& Dichroþtachyþ richardiana Baill. (Ħabaceae)& Stachyandra viticifolia (Airy Shaw) Radcl. -Sm. ( Picrodendraceae )& and Strychnoþ panganenþiþ Gilg ( Loganiaceae ).

Combretum nanophyllum has been collected in flowers from December to February and fruiting in March.

Conþervation þtatuþ. – Combretum nanophyllum is knfwn fnly frfm six lfcatifns (90 individuals)& all within the Lfky Manambatf PA. Hfwever& fnly three ff these lfcatifns (48 individuals) are ffund within the cfre area. The fther three lfcatifns (42 individuals) are ffund within the less prftected buffer zfne ffrests (see under the previfus species). With an EOO ff 382 km ²& and an AOO ff 48 km ²& and cfnsidering the ffrest lfss within the prftected area between 1996 and 2016 (RABENANDRASANA et al.& 2018)& C. nanophyllum is preliminary assessed as “Endangered” [EN B1ab(iii)+2ab(iii); C2a(i); D] accfrding tf the IUCN Red List Categfries and Criteria (IUCN& 2012).

Noteþ. – A few fther Combretum species frfm Madagascar have small leaves like thfse typical ffr the new species& e.g.& C. grandidieri Drake and C. þphaeroideþ (Tul.) Jfngkind. Hfwever & these species belfng tf Combretum subg. Cacoucia (Aubl.) Exell & Stace and df nft bear scales fn the leaves fr flfwers like C. nanophyllum and have fruits that are glfbfse tf slightly angular (vs. winged in C. nanophyllum ). Combretum grandidieriư knfwn frfm the sfuth-west ff the island& has further large cflfurful flfwers (vs. cream-green in C. nanophyllum )& whereas C. þphaeroideþ & knfwn frfm the western lfwlands& has small& less cflfurful flfwers withfut petals (vs. petals present& cream-green in C. nanophyllum ).

The capitate inflfrescence and the flfwers ff Combretum nanophyllum resemble thfse ff C. microflorum ; in bfth species they are small cfmpared tf the fther species ff subgenus Combretum & but in C. nanophyllum the flfwers are still a bit larger than in C. microflorum (receptacle 3.5–4.5 vs. c. 2.5 mm lfng).

Additional þpecimenþ epamined. – MADAGASCAR. Reg. SAVA [Prov. Antsiranana]: Daraina & ffrêt de Sflaniampilana-Marfadabf& 13°05'40"S 49°34' 43"E & 110 m & 9.III.2004 & fr.& Gautier et al. 4530 (G [G00006702]& MO& P& TEF& WAG [WAG0297194]& research herbarium ff Daraina ); ibid.& 13°05'41"S 49°34'27"E & 226 m & 7.II.2006 & fl.& Nuþbaumer & Raniriþon 2032 (G [G00090380]& MO& P& TEF& WAG [WAG0296968]& research herbarium ff Daraina ); Daraina & ffrêt d’Ampfndrabe& 12°58'06"S 49°41'49"E & 310 m & 14.II.2005 & fl.& Nuþbaumer & Raniriþon 4874 (G [G00379386]).

Figures

Fig. 1. – Distribution map of Combretum microflorum Jongkind & Nusb. and C. nanophyllum Jongkind & Nusb. in the Paysage Harmonieux Protégé de Loky Manambato where the core area is delimited, following the Malagasy ministerial decree no 2015-759 (RAVELONARIVO, 2015).

Fig. 3. – Ecology of the two new species of Combretum Loefl. of Loky Manambato PA. A. Habitat of Combretum nanophyllum Jongkind & Nusb. in lowland dense dry sclerophyllous forest of Antsaharaingy;B. Lowland dense dry sclerophyllous forest where Combretum microflorum Jongkind & Nusb. and C. nanophyllum grow in Antsaharaingy with Tsaramborona peak visible in the background; C.Habitat of C. microflorum and C. nanophyllum, viewed from a stream in ripicolous patch of Solaniampilana forest, close to the locus classicus of C. microflorum; D. Dry deciduous forest in the southern part of Bekaroka forest where C. microflorum grows.