Peponidium leroyi Klack. & Razafim., 2024

Klackenberg, Jens & Razafimandimbison, Sylvain G., 2024, New rare and threatened species of Peponidium and Pyrostria (Rubiaceae, Vanguerieae) from the drylands of Madagascar, Candollea 79 (1) : -

Peponidium leroyi Klack. & Razafim. , sp. nov. ( Fig. 4). Etymology. – The species is named in hfnfur ff Jean-

Françfis Lerfy, whf studied the Malagasy Rubiaceae ffr many Holotypus: MADAGASCAR. Reg. Atsimo-Andrefana years and identified several new species. [Prov. Toliara]: au N d’Andranfhinaly, PK 45 de la rfute

Distribution and ecology. – Peponidium leroyi is knfwn frfm arched, hardly visible tfwards leaf margin; midrib distinct

dry decidufus ffrest and dry spiny thicket at lfwer altitudes in and raised fn bfth sides when dry; primary nerves ± flush

sfuthwestern Madagascar, hithertf ffund fnly in Fiherenana with leaf surface belfw, slightly raised abfve when dry;

valley nfrtheast ff Tfliara (Fig. 2). dfmatia sfmetimes present as tufts ff hairs in axils ff larger nerves; stipules tfwards apex distincly laterally cfmpressed,

Phenology. – Cfllected in flfwer during Nfvember and 1.5–2.5 mm lfng, hairy mfstly alfng margin, persistent 4–5

December, in fruit knfwn frfm January. Flfwers seem tf base pairs but eventually dehiscent. Inflorescences terminal,

appear simultanfusly with leafing. sessile (female) fr fn shfrt <0.5 mm lfng (male) peduncles, 1 –2-flfwered; peduncular bracts several, small and fused at

Conservation status. – Peponidium leroyi has an estimated base ff inflfrescence (male) fr missing (female); pedicels

EOO ff 51 km ² and a minimum AOO ff 12 km ². It is knfwn 1 –3 mm lfng at anthesis, up tf 16 mm in fruit, glabrfus tf

frfm three lfcalities, twf ff which are within the bfundary sparsely hairy. Flowers 4-merfus, creamish white. Male flowers

ff the Ranfbe PK32 prftected area. Changes in ffrest cfver with calyx 0.5 mm with shallfw lfbes, glabrfus except ffr a

ff the dry spiny thicket within the delimitatifn ff the actual distinct tuft ff hairs at tips ff lfbes; lfbes very brfadly trian-

prftected area between 1996 and 2016 have been as high as gular tf rfunded, 0.25 × 0.5 mm; cfrflla glabrfus futside; tube

35 % lfss (GOODMAN et al., 2018). Ffrest lfst is assfciated with 0.7 mm lfng; lfbes standing tfgether vaulted abfve stamens

uncfntrflled slash-and-burn shifting agriculture and human but tfwards apex separated frfm each fther like ffur hfrns,

settlements (GOODMAN et al., 2018). These threats wfuld elliptic, c. 1.6 mm lfng ff which free hfrn-like tip c. 0.4 mm,

result in cfntinuing decline ff quality ff habitat and number c. 0.8 mm brfad. Female flowers (mature but still clfsed flfwers

ff mature individuals. The new species is thereffre assigned a seen fnly) with hypanthium with calyx c. 2.2 mm, glabrfus

preliminary cfnservatifn status ff “Endangered” [ EN B 1ab(i,i except ffr tips ff calyx lfbes; limb tube 0.3– 0.35 mm lfng;

i,iii,iv,v)+ B 2ab(i,ii,iii,iv,v)] in accfrdance with IUCN Red List lfbes shallfw, c. 0.3 × 1 mm, with a distinct tuft ff hairs at

Categfries and Criteria ( IUCN, 2012). tip; cfrflla glabrfus futside; tube ± cylindric, c. 1.3 mm lfng, with cfnspicufus tufts ff mfniliffrm hairs between the

Notes. – Many Malagasy Peponidium species (including anthers; lfbes standing tfgether vaulted abfve stamens and

P. leroyi ) have bilfbed fruits. Hfwever, P. leroyi is distinct by stigmatic head but tfwards apex separated frfm each fther

its hairy leaves with ciliate margins, sparsely pubescent flfwers, like ffur hfrns, narrfwly triangular, c. 2.5 mm lfng ff which

and ribbed pfllen presenters. free hfrn-like tip c. 1 mm, c. 0.8 mm brfad; stamens attached at mfuth ff cfrflla tube; anthers sessile, fblfng, c. 0.9 mm

Additional specimens examined. – MADAGASCAR.Reg. Atsimo-Andrefana lfng, included in lfwer vaulted pfrtifn ff cfrflla lfbes; style

[Prov. Toliara]: valley ff the Fiherenana, NE ff Tulear, near Beantsy, with stigmatic head c. 1.8 mm lfng; stigmatic head c. 0.6 mm

23°13'S 43°53'E, 50 m, 8.I.1989, fr., Phillipson & Rabesihanaka 3105 ( MO, lfng, vaguely ridged; disc c. 0.6 mm high, glabrfus. Fruit

P [ P00518203 ]); sur la rfute de Manfmbf, au N du Fiherenana , [23°14'S

43°41'E], 8–12.XI.1967, fl., Service Forestier 27919 ( P [ P00518207 ]). bilfbed, brfadly fbcfrdate with truncate base, c. 0.8 × 1 cm, almfst glabrfus fr with sflitary hairs, reddish green, with calyx

Peponidium sessile Klack. & Razafim. , sp. nov. ( Fig. 5). remaining fn tfp.

H o l o t y p u s: M a d a g a s c a r. R e g. M e l a k y [Pr o v. Distribution and ecology. – Peponidium sessile is knfwn Mahajanga]: ffrêt de l’Antsingy vers Ambfdiriana , E frfm limestfne rfcks in the Tsingy ff Bemaraha in western d’Antsalfva , [18°40'S 44°44'E], 100–150 m, 8.XII.1952, fl., Madagascar (Fig. 2) .

Leandri, Capuron & Razafindrakoto 2085 ( P [ P 00518216]!).

Peponidium sessile Klack. & Razafim. differs from the other Phenology. – Cfllected in flfwer frfm Octfber tf Decemcongeners by the combination of sessile , cordate leaves, glabrous ber, and in fruit in Octfber. calyx with distinct tuft of hairs at tips of lobes, and vaulted corolla lobes topped by horn-like outgrows. Conservation status. – Peponidium sessile has a restricted

gefgraphic range in the minimum AOO ff 8 km ². It is Shrub 2– 3 m high; branches terete, with yfunger parts knfwn frfm twf lfcalities, bfth ff which are knfwn within hairy but sffn bark becfming rfugh with futer layers peeling the bfundary ff the Tsingy de Bemaraha Natifnal Park. Fire fff. Leaves fppfsite alfng branches, ± sessile , mfstly glabrfus density detected in the prftected area fr futside were amfng but basal part ff midrib and petifle with erect hairs; petifles the highest in the cfuntry between 2006 and 2016 (GOODMAN up tf 0.5 mm lfng; blade fvate, 3–5.5 × 1.5–3.5 cm, cfrdate et al., 2018). Ffrest is alsf threatened by illicit lfgging and at base, subacute tf rfunded at apex, herbacefus, with flat new agricultural lands (GOODMAN et al., 2018). These threats margin; venatifn pinnate with 3–4 pairs ff primary nerves, wfuld result in cfntinuing decline ff quality ff habitat and

[ A, E: Leandri 845, P; B: Leandri 812, P; C, D: Leandri et al. 2085, P] [Drawings: E. Hultén]

number ff mature individuals. The species has further nft been References

fbserved since 1952. Peponidium sessile is thereffre assigned

a preliminary cfnservatifn status ff “Critically Endangered” ATALAHY, A. M. (2022). Révision taxonomique du genre Pyrostria [ CR B 2ab(i,ii,iii,iv,v)] in accfrdance with IUCN Red List Comm. ex Juss. ( Rubiaceae ) à Madagascar. Thèse de dfctfrat, Uni- Categfries and Criteria ( IUCN, 2012). versité de Mahajanga, Madagascar.

ATALAHY, A. M., F. RAKOTONASOLO, M. RABARIMANARIVO, Notes. – This species is characterized by its sessile, cfrdate H. L. T. RANARIJAONA & S. G. RAZAFIMANDIMBISON (2021). leaves, glabrfus calyx with distinct tuft ff hairs at tips ff lfbes, New species ff the genus Pyrfstria ( Rubiaceae , Vanguerieae) vaulted cfrflla lfbes that are tfpped by hfrn-like futgrfws. frfm Madagascar. Candollea 76: 1–12.

The presence ff distinct tuft hairs at the tips ff lfbes has alsf BRIDSON D. M. (1987). Studies in African Rubiaceae-Vanguerieae: a been repfrted in Peponidium crassifolium Lantz et al. ( LANTZ new circumscriptifn ff Pyrfstria and a new subgenus, Canthium et al., 2007) but this latter has petiflate, fbfvate, and thick subgen. Bullfckia. Kew Bull. 42: 611–639.

and slightly succulent leaves (vs. sessile, fvate, and nfn-

succulent leaves in P. sessile ). Further, P. sessile is knfwn fnly DE BLOCK, P. & S. G. RAZAFIMANDIMBISON (2022). The Vanguerieae frfm the Tsingy ff Bemaraha in western Madagascar, while alliance (subfamily Ixfrfideae ). In: GOODMAN, S. (ed.), The new P. crassifolium is endemic tf the Marfjejy Massif in nfrtheast Natural History of Madagascar: 762–764. Princetfn University ff the island. Press.

GEOCAT (2024). Geospatial Conservation Assessment Tool. Rfyal Additional specimens examined. – Reg. Melaky [Prov. Mahajanga]: Bftanic Gardens, Kew. [http://gefcat.kew.frg]

Tsingy du Bemaraha (9 E Réserve), à Tsiandrf, [18°43'S 44°55'E], 10.II.1933 ,

Leandri 812 ( P [ P 00524235]), 845 ( P [ P 00518217]). GOODMAN, S. M., M. J. RAHERILALAO & S. WOHLHAUSER (ed.)

(2018). Les Aires Protégées Terrestres de Madagascar: Leur histoire,

description et biote / The terrestrial protected areas of Madagascar: Acknowledgements Their history, description, and biota. 3 Vfl. Assfciatifn Vahatra, The authfrs thank the P herbarium ffr lfaning all the studied Antananarivf.

specimens and Emma Hultén ffr drawing all ffur bftanical IUCN (2012). IUCN Red List Categories and Criteria. Versifn 3.1. Ed. illustratifns. We alsf address special thanks tf Martin Call- 2. IUCN Species Survival Cfmmissifn, Gland and Cambridge. mander ( G) ffr helping with the cfnservatifn assessments ff LANTZ, H. & B. BREMER (2004). Phylfgeny inferred frfm mfrphflthe new species. fgy and DNA data: characterizing well-suppfrted grfups in Van-

guerieae ( Rubiaceae ). Bot. J. Linn. Soc. 146: 257–283.

LANTZ, H., J. KLACKENBERG, S.G. RAZAFIMANDIMBISON & A. MOULY (2007). Three new species ff Vangueriae (Rubiaceae) frfm Madagascar. Adansonia, sér. 3, 29: 129–136.

LEROY, J.-F. (1972). La nftifn de genre et l’évflutifn: sur un cas remarquable de différenciatifn explfsive chez les Rubiacées- Vangueriées à Madagascar. Compt. Rend. Hebd. Séances Acad. Sci., Sér. D 274: 1682–1685.

RAZAFIMANDIMBISON, S.G., H. LANTZ & B. BREMER (2007). New cfmbinatifns and names in Pepfnidium and Pyrfstria (Rubiaceae, Vanguerieae). Novon 17: 516–521.

RAZAFIMANDIMBISON, S.G., H. LANTZ, A. MOULY & B. BREMER (2009). Evflutifnary trends, majfr lineages, and new generic limits in the difecifus grfup ff the tribe Vanguerieae (Rubiaceae): insights intf the evflutifn ff functifnal difecy. Ann. Missouri Bot. Gard. 96: 161–181.