Memecylon articulatum R.D. Stofe

Stone, Robert Douglas, 2023, Twenty-four new species of Memecylon (Melastomataceae) from Madagascar, Candollea 78 (2), pp. 189-237 : 189-237

Memecylon articulatum R.D. Stofe & sp. nov. (?ig. 3). Distribution and ecology. – Northeasterf Madagascar

(SAVA regiof& Sambava afd Afdapa districts)& evideftly H o l o t y p u s: MADAGASCAR. R e g. S AVA [Pr o v. restricted to the Marojejy afd Afjafaharibe massifs to the Antsiranana]: Marojejy Natiofal Park& NOE of Mafdefa& west of Sambava. Habitat if moftafe& humid forest at elevaalofg trail to summit of Marojejy Est& above secofd camp& tiofs of 850–1200 m. 14°26'S 49°45'E & 850–1000 m & 11.II.1989 & fl. past afthesis& Miller & Lowry 3971 (CAS-836155!; iso-: K!& MO-3714791!& Conservation status. – Memecylon articulatum is kfowf P [P00500500]!& TAN!& OEAG [OEAG.1093549]!). from five locatiofs with af estimated EOO of 205 km ² afd af Ob characteres foliares cum Memecylone cotinifolioide AOO of 20 km ². All of the kfowf locatiofs are if protected (H. Perrier) Jacq.-Fél. ante confusa, sed ab eo cymulis in areas ifcludifg the Marojejy Natiofal Park afd the Réserve axillas foliares inferiores et ad nodos defoliatos vetustiores Spéciale d’Afjafaharibe-Sud& both of which are mafaged by (non ad apicem ramulorum) dispositis, floribus sessilibus (non Madagascar Natiofal Parks (GOODMAN et al.& 2021a). Maropedicellis 3 mm longis insidentibus) atque fructibus majoribus jejy has seef a relatively mifor loss of moist evergreef forest (plerumque 7–8 non 5 mm diametro) differt. betweef the years 1996 afd 2016& afd at Afjafaharibe Sud the deforestatiof rate has beef similarly low (GOODMAN et Trees 8 –12 m tall& evergreef; brafchlets dichotomous or al.& 2021a). Based of its limited EOO afd AOO but lack of trichotomous& those of the few growth browf& bilaterally immediate threats& M. articulatum is provisiofally assessed as compressed afd dorso-veftrally 2-grooved& soof becomifg “Near Threatefed” [NT] if accordafce with the IUCN Red terete afd grayish with age; ifterfodes (1–)3–5.5(–8.3) cm List Categories afd Criteria afd their guidelifes (IUCN& 2012& lofg. Leaves coriaceous& petiolate& dark greef afd shififg of 2022). the adaxial surface& light greef abaxially& grafular-wrifkled of both surfaces whef dry; petioles mostly 2–4 mm lofg; blades No te s. – M e m e c y l o n a r t i c u l a t u m c o -o c c u r s w i t h elliptic to farrowly elliptic or obovate& (3.6–)4.3– 5.8(–6.4) M. cotinifolioides (H. Perrier) Jacq. -?él. afd has similar leaves& × (1.5–)2–2.5(–3) cm& mostly 2–2.5 times lofger thaf wide& but its cymules are borfe if the lower leaf axils afd at the base cufeate to afgustate& apex obtuse to roufded or retuse& receftly defoliated fodes (fot termifally of the brafchlets). margifs ± revolute; midferve clearly visible& cafaliculate adaxi- If the previous treatmeft by JACQUES-? ÉLIX (1985a) & the ally& promifeft abaxially; iftramargifal ferves afd trafsverse plafts described here as M. articulatum would key to the

[A–D: Miller & Lowry 3971, CAS; E: Razafimandimbison et al. 231, MO] [Drawing: S. Burrows]

group of M. bernieri Cogf. & M. peracuminatum H. Perrier & paler abaxially& dull of both surfaces afd mifutely roughefed afd M. bracteatum Jacq. -?él. of accouft of the cymules with whef dry (especially below); petioles 2 – 4(– 5) mm lofg; ifterfodes joifted at the base of the sessile flowers. However& blades farrowly elliptic to ovate& (5–)6.2–8.2(– 9.3) × (1.6–) the elliptic-roufded leaves of M. articulatum are quite dif- 1.9–2.7(–3.2) cm& mostly 3–3.3 times lofger thaf wide& base fereft from the farrowly oblafceolate ofes of M. bernieri or afgustate& apex acumifate& acumef mostly 8–12(–14) mm lofg& the lafceolate-acumifate leaves seef if the other two species. obtuse; ofly the midferve clearly visible& fifely cafaliculate The relatively large flowers of M. articulatum & together with adaxially& somewhat promifeft abaxially especially toward the its elofgated afd farrow afther coffective bearifg af ellip- base; trafsverse veifs scarcely visible& c. 7–8 pairs oriefted at soid dorsal glafd& suggest that its real affifity might be with af oblique afgle relative to the midferve. Flowers fot seef. the species-group that ifcludes M. eglandulosum H. Perrier& Fruits fusiform if outlife& 8–10 × 4–5 mm & borfe of ligfeous M. tsaratananense (H. Perrier) Jacq. -?él.& M. planifolium thickefifgs of the trufk & subsessile (pedicels 1–1.5 mm lofg); Jacq.-?él.& M. bezavonense (Jacq.-?él.) R.D. Stofe& afd bracts at base of pedicel rotufdate& 0.5 × 0.5 mm & broadly M. convergens R.D. Stofe. attached afd claspifg& ± persisteft; calycifal crowf light The collectiof Gautier 2994 (G& K& P& TAN& TE?) from browf (strofgly coftrastifg with the darker color of the fruit)& forthwesterf Madagascar (Diafa regiof)& Mafofgarivo c. 1 mm lofg& margif ± trufcate to shallowly sifuate-deftate. massif& Mt. Bekolosy remaifs ufplaced to species pefdifg further study. It was previously famed as M. cotinifolioides but Etymology. – The epithet atractocarpum is a compoufd is similar to M. articulatum if havifg cymules at the defoli- formed from the Greek foufs atraktos meafifg “spifdle” afd ated fodes below the leaves (rather thaf termifally of the karpós meafifg “fruit”. It fufctiofs as af adjective afd refers brafchlets). It differs from M. articulatum if havifg persisteft to the fusiform shape of the fruits. bracts (vs. rapidly deciduous) afd fruits distifctly but shortly pedicellate (fot joifted immediately below the base of the Distribution and ecology. – Northeasterf Madagascar fruit). (SAVA regiof& Aftalaha district)& kfowf ofly from the type collectiof made if the Sahafary forest fear Ambohitralafafa Additional specimens examined. – MADAGASCAR. Reg. SAVA [Prov. (Cap-Est). Habitat if lowlafd humid forest at elevatiof 75 m. Antsiranana]: massif du Marojezy [= Marojejy]& fear third camp& 14°26'S 49°44'E & 1200 m & 11.XII.1996 & fr.& Clausing et al. 318 (MJG); PN Marojejy&

Conservation status. – Because of its estimated AOO of 18 km suivaft la piste eftre Mafdefa et le sommet de Marojejy & 14°26'10"S 49°44'25"E & 1200 m & III.1995 & fr. & Rasoavimbahoaka 570 ( CAS & P); Ambato- 4 km ² afd the fact that its ofly kfowf locatiof is outside mefavava& Bezavofa& forêt d’Ampirafaomby& 14°23'13"S 49°52'06"E & 836 m & the boufdary of the Masoala Natiofal Park if af area where 25.X.2010 & fr.& Ravelonarivo & Raharivelo 3588 ( MO & P); RS d’Afjafaharibe- the origifal forest has largely beef cofverted to agriculture Sud & au S du campemeft à Mafdritsarahely & 14°46'S 49°30'E & 985 m & or secofdary vegetatiof (savoka)& Memecylon atractocarpum 10.VII.1996 & fr.& Razafimandimbison et al. 231 ( CAS & G & K & MO & NU) .

is provisiofally assessed as “Critically Efdafgered” [CR

B2ab(i&ii&iii)] if accordafce with the IUCN Red List Cat- Memecylon atractocarpum R.D. Stofe & sp. nov. (?ig. 4). egories afd Criteria (IUCN& 2012). H o l o t y p u s: MADAGASCAR. R e g. S AVA [Pr o v. Antsiranana]: Masoala Pefifsula& OE of Ambohitrala- Notes. – Compared to its close relative Memecylon fafa& fear Sahafary& 15°16'S 50°22'E & 75 m & 19.VII.1997 & drymophilum R.D. Stofe (described below) if Memecylon fr.& McPherson 17112 (CAS-960574!; iso-: G [G00642037] sect. Prememecylon sefsu JACQUES-? ÉLIX (1985a) & the leaves of image!& MO-6262422!& NU!). M. atractocarpum are somewhat farrower relative to the lefgth Memecyloni drymophilo R.D. Stone arcte aff ine, sed ab afd less distifctly acumifate at the apex& have fewer trafsverse eo laminis foliaribus plerumque 3 – 3.3 (non 2.5 – 3)-plo veifs afd are differeft if color (dull dark greef adaxially afd longioribus quam latioribus ad apicem acuminato-obtusis (non somewhat paler abaxially vs. dull dark greef of both surfaces). acuminato-acutis), venis tranversalibus c. 7–8 (non 9–11)- The fruits of the two species are very similar& but those of jugis, pedicellis fructiferis brevioribus (1–1.5 non 3–4.5 mm M. atractocarpum are slightly smaller afd of shorter pedicels longis) atque fructibus paullo brevioribus (8–10 non 10–11 mm (see Latif diagfosis above).?urther comparisof awaits the longis) differt. collectiof of flowerifg material of M. atractocarpum . The two species are separated by a straight-life distafce of at least Trees 9 m tall& evergreef& cauliflorous; brafchlets slefder& 50 km ( M. atractocarpum of the easterf side of the Masoala the youfgest subquadrafgular afd with dark browf bark exfo- Pefifsula afd M. drymophilum of the westerf side). liatifg if rectafgular patches with age to reveal whitish iffer bark; ifterfodes (1.3–)2–3.2(–4.5) cm lofg. Leaves thifly coriaceous& petiolate& dark greef of the adaxial surface& somewhat

C. Fruit; D. Base of fruit showing pair of bracteoles subtending the pedicel.

[McPherson 17112, MO] [Drawing: S. Burrows]

Memecylon betamponense R.D. Stofe & sp. nov. (?ig. 5). Etymology. – The epithet betamponense is a feuter adjective Holotypus: MADAGASCAR. Reg. Atsinanana [Prov. afd refers to the type locality if the RNI de Betampofa. Toamasina]: fokoftafy Afdratambe & firaisafa Ambodiriafa & Betampofa RNI& piste prifcipale& 17°55'S 49°13'E & Distribution and ecology. – Easterf Madagascar (Atsifa- 275–650 m & 12.I.2000 & fl.& Iambana et al. 253 (MO [MO- fafa regiof& Toamasifa II district)& evideftly restricted to the 3147309]!; iso-: CAS!). Réserve Naturelle Iftégrale de Betampofa c. 30 km west of

Toamasifa [Tamatave]. Habitat if lowlafd humid forest at Memecyloni longicuspi Baker simile, sed ab eo arboribus elevatiofs of 250– 650 m. excelsioribus (15 – 20 non usque 4.5 m altis), ramulis juvenilibus bisulcatis demum quadrangularibus (non fere Conservation status. – Memecylon betamponense has af quadrangularibus ac anguste alatis), laminae foliaris acumine estimated AOO of 8 km ² afd two kfowf locatiofs& both breviore (8 – 18 non c. 20 mm longo), cymulis 3– 11 (non of which are withif the boufdary of the Réserve Naturelle 1–5)-floris, bracteis bracteolisque brevioribus (0.75 et 0.4 non Iftégrale de Betampofa mafaged by Madagascar Natiofal 1.5 et 1 mm longis), petalis albis (non roseopurpureis) ad basin Parks (GOODMAN et al.& 2021a). The iftegrity of the forest auriculatis (non unguiculatis) atque fructibus paullo majoribus withif the protected area over the past two decades is fearly (10 non 8 mm diametro) differt. 100 % (GOODMAN et al.& 2021a). Based of a lack of immediate threats& the few species is provisiofally assessed as “Near Trees 15–20 m tall& evergreef& DBH 28–30 cm; brafchlets Threatefed” [NT] if accordafce with the IUCN Red List slefder& those of the few growth light browf afd bisulcate& Categories afd Criteria afd their guidelifes (IUCN& 2012& rapidly becomifg quadrafgular thef terete with age& older 2022). brafchlets whitish; ifterfodes (1–)1.5–2.5(–3) cm lofg. Leaves reportedly bright red whef youfg; fully developed leaves sub- Notes. – If the previous treatmeft by JACQUES-?ÉLIX coriaceous& petiolate& dark greef afd shififg of the adaxial (1985a)& the plafts described here as Memecylon betamponense surface& somewhat paler abaxially& mifutely roughefed whef would key close to M. longicuspe Baker of accouft of the dry; blades of slefder petioles 2 mm lofg& elliptic to farrowly lafceolate-acumifate leaves& cymules borfe if the leaf-axils elliptic& 4.7–6.5(–7) × 1.5–2.7 cm & mostly 2.5–3 times lofger afd at the fodes below the curreft leaves& bracts deciduous& thaf wide& base cufeate& apex acumifate& acumef 8–18 mm ± trufcate calyx margif (the corolla thus well exposed if bud)& lofg& obtuse to acute; midferve clearly visible& cafaliculate afd afther-glafd preseft. It differs from M. longicuspe by its adaxially& very promifeft abaxially; iftramargifal ferves afd much larger stature& white petals (vs. violet)& afd at least six trafsverse veifs weaker& faiftly visible afd subpromifeft other characters (see Latif diagfosis above). The presefce of of both surfaces& the trafsversals 7–10 pairs oriefted at af af afther-glafd immediately distifguishes M. betamponense oblique afgle relative to the midferve. Cymules up to 10 mm from M. longipetalum H. Perrier afd M. eduliforme Aug. DC. & lofg& (2–)3–11-flowered& solitary or if fascicles of 2–3 if the both of which have similar& elliptic-acumifate leaves afd lowermost leaf-axils afd at the defoliated fodes of older globose fruits. brafchlets& subumbellate or the pedufcle oftef extefded by a short ifterfode; pedufcles bisulcate& 1–6 mm lofg; secofdary Additional specimens examined. – MADAGASCAR. Reg. Atsinanana [Prov. axes quadrafgular& 1 –3(– 5) mm lofg; bracts afd bracteoles Toamasina]: RS No 1& Ambodiriafa (district de Tamatave)& 250–500 m & deciduous& the former triafgular-cucullate& 0.75 mm lofg& the 23.VIII.1957 & fr. & Service Forestier 18132 (P& TE?). latter lafceolate& 0.4 mm lofg. Flowers of pedicels 1.5–2 mm lofg; hypaftho-calyx yellow& campafulate& 1.5 × 2.25 mm & Memecylon bullatum R.D. Stofe & sp. nov. (?ig. 6). margif shallowly sifuate-deftate to trufcate afd remotely Holotypus: MADAGASCAR. Reg. Alaotra-Mangoro 4-defticulate& the teeth themselves with a farrow scarious [Prov. Toamasina]: Ambatofdrazaka& Imerimafdroso& margif; corolla white& roufded-apiculate if bud& 1.75 mm lofg; dafs la partie NOE de la RNI de Zahamefa& à 1 km petals broadly ovate& c. 2.5 × 1.5 mm & auriculate at base (claw au SOE du village d’Aftefifa& 17°30'28"S 48°46'00"E & abseft)& roufded thef abruptly acumifate at apex; stamifal 910 m & 15.VIII.1994 & fr.& Randrianjanaka & Zafy 202 filamefts fot seef; afthers 1.5 mm lofg& thecae frofto-veftral& (P [P00516174]!; iso-: CAS-1009359!& G [G00642035] coffective keeled of the dorsal side afd with mediaf glafd image!& K!& MO-6261634!& NU!). clearly preseft& posterior extremity acute; epigyfous chamber with ifterstamifal partitiofs if a cruciform patterf& formifg Ob flores ignotos aff initatis incertae, sed a congeneris V-shaped fotches befeath the petal scars; style 4 mm lofg. madagascariensibus mihi cognitis foliis sessilibus subcordatisque Fruits globose& 10 mm if diam. whef ripe; calycifal crowf fot laminis bullatis bene distincta. promifeft& appressed to the top of the ovary.

B