Revision of Eugenia and Syzygium (Myrtaceae) from the Comoros archipelago Author Byng, James W. Author Barthelat, Fabien Author Snow, Neil Author Bernardini, Benedetta text Phytotaxa 2016 2016-03-14 252 3 163 184 http://dx.doi.org/10.11646/phytotaxa.252.3.1 journal article 10.11646/phytotaxa.252.3.1 1179-3163 13673290 3. Eugenia comorensis H. Perrier (1952: 174) Type: — MAYOTTE [ FRANCE ]. Forêt de Combani , April 1884 , Humblot 1406 ( holotype P! [barcode P00118102]; isotype P! [barcode P00118101]). Figure 5 . Eugenia anjouanensis H. Perrier (1952: 172) . Type : — UNION OF THE COMOROS . Anjouan , Humblot 1486 ( holotype P! [barcode P00101246]; isotype P! [barcodes P00101247, P00466141]), syn. nov . FIGURE 5. Eugenia comorensis H.Perrier. A lower leaf surface; B upper leaf surface; C immature fruits; D inflorescence; E male flower; F functionally female flower; G functionally female flower, arrow indicating style and stigma. ( A–E from Byng 109 ; F–G from Byng 111 ). Scale bar = 2 cm ( A–B ) or 5 mm ( D–G ). Trees or shrubs to 15 m ; bark brown to grey. Branchlets 1–4 mm in diameter, drying light brown to grey, glabrous. Petiole 3–13 mm long, thick, somewhat reddish to violet when young. Leaves opposite or subopposite, coriaceous, drying pale olive green beneath, olive green to dark greenish-brown above. Blades 4–21 × 2–8 cm , oblong, elliptic, elliptic-lanceolate or lanceolate; base round or cuneate, apex acute to acuminate; midvein pale green or brown when dry; secondary vein pairs 7–14, parallel, obscure to visible above but distinct beneath; intramarginal vein 1–6 mm from the margin. Inflorescences axillary, sometimes ramiflorous, solitary or fascicled, 2–12-flowered. Bracteoles deltoid to narrowly triangular, 0.5–1 mm long, tinged magenta to dark purple, persistent or caducous. Pedicels 1–12 mm . Flowers 5–10 mm in diameter at anthesis, buds ca. 3 mm in diameter. Calyx lobes ca. 2 × 2–3 mm , semi-orbicular, equal, sometimes tinged magenta when young, gland-dotted. Petals 2–5 × 2–3 mm , orbicular, creamy-white, gland-dotted. Stamens> 40, filaments ca. 2–5 mm long, white; anthers ca. 1 mm long, oval, basifixed. Style in female flowers ca. 4 mm long, stigma bifid, ‘Y’-shaped, ca. 2.2 mm wide at apex. Style in male flowers rudimentary, ca. 1 mm long. Fruits 0.7–3 × 0.7–3 cm , globular to ellipsoid, green or yellow to reddish becoming purplish to black at maturity, crowned by persistent calyx. Distribution:— Endemic to the Comoros archipelago ( Union of the Comoros , Mayotte [ France ]). Habitat and ecology:— Dense humid secondary forests, lowland hill forests, to montane forests and ridges from 200‒1000 m elev. Vernacular names:— Fandrabone, (dialect Mohelien), N’songoma msinou, Sary soaravo (dialect Shibushi), Shivisasheu (dialect Shindzuani), Sari Soua Ravou (dialect Shibushi & Shimaoré). Additional specimens examined:— MAYOTTE [ FRANCE ]. Benara, 3 August 1999 , C. Mas 345 (P!). Hachiroungou, 26 October 2001 (fl.), F. Barthelat 570 (K!, MAYOTTE !, MO, P!). Mlima Choungi, 19 July 1996 (fr.), O. Pascal 562 ( MAYOTTE !, P!). Mont Combani, 10 April 2002 (fr.), F. Barthelat 829 (K!, MAYOTTE !, MO) ; 25 November 2000 (fl.), J.-N. Labat 3295 (G, K!, MAYOTTE !, MO, WAG, P!) ; November 2011 (fl., fr.), J.W. Byng 109 ( PG !, P!) ; November 2011 , Byng 111 ( PG !, P!). Sohoa , 11 December 1995 (fl.), O. Pascal 273 (K!, MO, P!). Tchaourembo , 19 March 1996 (fr.), O. Pascal 428 ( MAYOTTE !, P!). Vahibé , 1 July 1997 (fl., fr.), O. Pascal 945 ( MAYOTTE !, P!) . UNION OF THE COMOROS . Anjouan : southern ridge of Mont Tringi , 16 November 2011 , J.W. Byng 117 ( PG !, P!). Col de Poby , 14 October 1968 (fr.), H.J. Schlieben 11133 (K!) ; Dzialandze , 3 March 2006 (fr.), J.-N. Labat 3758 (P!, CNDRS, G, K!, MO). Grande Comore : Forêt de la Grille , bord de la RR 105 à 2 km de Maoueni vers Oussoudjou, 17 July 2000 , S. Brionnaud et al. 9 (CNDRS, K!, MO, P!) ; Plateau de Dibwani , 23 November 2009 (fl.), C. Loup 519 (G!, HKM!, K!, P!) ; Massif de la Grille , 1 December 2004 (fl.), F. Barthelat 1415 ( MAYOTTE !, P!) ; 4 December 2004 (fl.), F. Barthelat 1440 ( MAYOTTE !, P!) ; 8 June 2006 (fr.), J.-N. Labat 3792 (CNDRS, G, K!, MO, P!); 9 January 1975 (with flowers and fruits), J.J. Floret 609 (CNDRS, P!); 9 November 2008 (fl.), M. Pignal 3531 (G, K!, MO, P!). Forêt de Karthala , au-dessus de Djoumamilima , 27 January 1975 (fl.), J.J. Floret 676 (P!). Mohéli: Forêt de Crête à l’ouest du chalet Saint Antoine, 28 February 1975 (fr.), J.J. Floret 1236 (CNDRS, P!) ; 28 February 1975 , J.J. Floret 1239 (CNDRS, P!). Piste du Radjo au sommet du plate du M’ze, Koukoule, 12 November 1970 (fl.), H. Jacquemin 862 (CNDRS, P!). Forêt de St. Antoine , Miringoni, 20 March 1957 (fr.), Service Forestier 16752 (P!). Forêt du mont Kimbonana, 27 February 1975 (fr.), J.J. Floret 1212 (CNDRS, P!). Ravines boisées des montagnes de Moëly , March 1850 (fr.), L.H. Boivin s.n. (P!) . Conservation status:— This species is known from several locations in natural (mostly dry) forests but also in sunny clearings and forest edges in humid zones. Much of the native forest on the islands is under threat from small scale agricultural expansion and invasive species, which are having a detrimental effect on the native flora. This species is known from numerous localities with a total AOO of about 65 km 2 . Eugenia comorensis should be considered Endangered (EN B2ab(iii)) according to the IUCN Red List Criteria ( IUCN 2014 ). Notes:— Eugenia anjouanensis is here synonymised based on the molecular, morphological and palynological evidence presented above. As both species were published simultaneously, the name E. comorensis is retained because it is widespread across the archipelago, whereas the name E. anjouanensis implies a distribution centred on or restricted to Anjouan . 4. Eugenia pascaliana Byng, Bernardini & N. Snow , sp. nov. Type : — MAYOTTE [ FRANCE ]. Boungoudranavi , 9 December 1996 (fl.), O. Pascal & J.-N. Labat 774 ( holotype P! [barcode P00144734]; isotypes G, K!, MO!, WAG). Figure 6 A low elevation species similar to E. comorensis but differing in the markedly coriaceous leaves, unequal calyx lobes, pink petals, and the fasciculate, cauliflorous inflorescence. FIGURE 6. Eugenia pascaliana Byng, Bernardini & N. Snow. A cauliflorous inflorescence on raised clumps composed of functionally female flowers; B close-up of functionally female flowers and buds, arrows indicating style and stigma. ( A–B from O. Pascal & J.-N. Labat 774 ; C–D from Barthelat 1690 ; E from J.-N. Labat 2711 ). ( A–E MNHN). Scale bar = 5 mm ( A–B ) or 1 cm ( C , E ). Shrubs or small trees to 5 m ; bark grey. Branchlets 1–4 mm in diameter, drying light grey to light brownish, compressed, glabrous. Petioles 3–5 mm long, reddish-purple when young. Leaves opposite or sub-opposite, markedly coriaceous, drying dull light brown or green beneath, dark green to brownish-green above. Blades 5.5–10.7 × 2.5–5 cm , elliptic; base round, apex acute or broadly acuminate; mid-vein reddish when dry; secondary vein pairs 7–10, parallel, obscure to noticeable above and beneath; inner intramarginal veins 2–5 mm from the margin, outer intramarginal vein ca. 1 mm and obscure. Inflorescences cauliflorous on raised clumps on parts of the trunk, 1–many-flowered. Bracteoles triangular, ca. 0.5 mm long, tinged magenta, persistent. Pedicels up to 1 mm in male flowers, 3–4 mm in female flowers. Flowers ca. 3–4 mm in diameter at anthesis, buds ca. 1–2.5 mm in diameter. Calyx lobes ca. 1 × 1 mm , orbicular, unequal, slightly tinged crimson when young, becoming almost completely crimson to magenta after anthesis, gland-dotted. Petals 1–2 × 1–2 mm , orbicular, pink, gland-dotted. Stamens few, <50; filaments 1–2 mm long, pink; anthers < 1 mm long, oblong, sub-basifixed. Style in female flowers ca. 3 mm long, stigma bifid (‘T’-shaped), ca. 1.5 mm wide at apex (horizontal part). Style in male flowers rudimentary. Fruits ca. 1 × 0.8 cm , globular to ellipsoid, yellow or green becoming reddish-black at maturity, crowned by persistent calyx. Distribution:— Endemic to Mayotte [ France ]. Habitat and ecology:— Lower hill forest from 150–300 m elev. Vernacular name:— Sary suara vu lahi keli (dialect Shibushi). Etymology:— The species is named after Olivier Pascal, who collected the type specimen and undertook extensive surveys on the flora of Mayotte . Paratypes :— MAYOTTE [ FRANCE ]. Mtsamboro Grange Terre , Réserve Forestière d’ Hachirongou , 15 November 2006 (fl.), F. Barthelat 1690 ( MAYOTTE !, P!) ; 16 November 1996 (with immature fruits), O. Pascal 835 ( MAYOTTE !, P!) ; Forêt de Dapani , 11 April 1996 (fr.), J.-N. Labat 2711 (K!, MAYOTTE !, MO, P!) . Conservation status : — The species is only known from four individual mature trees at three subpopulations with a total AOO of 1 km 2 . Each locality is threatened by invasive species and small scale agricultural practices. Eugenia pascalia should be considered Critically Endangered (CR C2a(i,ii); D) according to the IUCN Red List Criteria ( IUCN 2014 ). Notes : — The species is similar to Eugenia comorensis but differs notably by the few-flowered inflorescences that arise from raised outgrowths along the lower portions of the stem. The specimens Pascal & Labat 774 and Barthelat 1690 , which respectively represent male and female forms, are recognised here as a single species. They differ vegetatively in the dried colour of the leaves, green in Barthelat 1690 , and with Pascal & Labat 774 drying pale brown below darker above and having slightly longer petioles and pedicels in the former. Florally they are remarkably similar except for the absence of a style in Pascal & Labat 774 and the conspicuous bifid stigma and prominent style on Barthelat 1690 . We conservatively recognise these as being one species but further fieldwork and collections are needed to test whether they should be considered different entities.