A synopsis of the Sabicea floribunda group (Rubiaceae) from Central Africa, including three new species Lachenaud, Olivier Zemagho, Lise Sonké, Bonaventure Candollea 2020 2020-06-17 75 1 115 143 4TVFK 172256 var. floribunda [836,1190,374,398] Magnoliopsida Rubiaceae Sabicea Plantae Gentianales 11 126 Tracheophyta variety floribunda floribunda   ( Fig. 7A).   Distribution, ecology and phenology. – This taxon occurs in Atlantic Central Africa, mostly from southern Cameroonto east-central Gabonwith a disjunct occurrence in southeastern Nigeriaand adjacent western Cameroon( Fig. 8). Its distribution marginally overlaps with those of var. paucinervisin the west of its range and of var. anisostegiain the east. It occurs in forest edges and regrowth, often along roads, 0–510 min elevation, and is locally abundant. Flowers probably all year (recorded from all months except March, June and September); fruits from February to June.   Conservation status. – The extent of occurrence (EOO) of  S. floribundavar. floribundais calculated to be 187,299 km², well above the limit for “Vulnerable” status under subcriterion B1. Its area of occupancy (AOO) is estimated to be 84 km², which falls within the limit for “Endangered” status under subcriterion B2, but is an obvious underestimation, given the low collecting density in most of its range. The taxon occurs in Central Africa from Nigeriato Gabon, and is known from 26 specimens. It is a locally common plant of secondary forest habitats, and not in any way threatened; consequently it is here assessed as “Least Concern” [LC] using the IUCN Red List Categories and Criteria ( IUCN, 2012).   Notes. – This taxon is morphologically (and also geographically) intermediate between  S. floribundavar. paludosaand var. paucinervis, differing from the former in the shape and indumentum of its bracts, and from the latter by its stems and leaves being more hairy, the latter with more numerous secondary veins.   Additional material studied. –   CAMEROON. Reg. South: au S de Zingui,  20.I.1962, fl.,  Letouzey4043( BR, K, P, WAG, YA);  Ebemwok(  55 kmW Ebolowa),  13.III.1963, imm.fr.,  J. & A. Raynal10435( P, YA);  Bebai, Campogebiet,  14.XII.1908, buds,  Tessmann716( K);  Bipindi, 1898, buds,  Zenker1820( BM, G, K, P, WAG);  Bipindi, 1904, fl.,  Zenker3232( BM, BR, K).   Reg. Southwest: Abonando,  5.V.1902, buds,  Rudatis52( K).    EQUATORIAL GUINEA. Centro-Sur: Monte Mitra,  28.XI.1997, fl.,   Obama315( BRLU, WAG);  SE of Bata c. 50 km, Oborobikó,  25.II.1969, fl. (fallen),  Sanford6034( K);  Ayaguening( Akonangui),  11.VIII.2001, buds,   Sonké2518( BR, BRLU);   8 kmN de Mitong,  13.XII.2003, buds,   Sonké3157( BR, BRLU, K).   Litoral: rte d’exploitation chantier SEMGE vers le 1er pont sur Mitemelé,  13.VI.1988, fr.,  Dibata451( BR, K, WAG);  de Sendje à Ongamnsok,  19.II.2001, imm.fr.,  Lejoly01/08( BRLU);  rte de Nco vers Misobong au niveau de la grande cascade,  9.I.1998, fl.,  N. Nguema& Lejoly206( BRLU).    GABON. Estuaire: Forêt de Mondah on road Libreville-Cap Esterias,  26.II.1999, imm.fr.,  Andersson& Nilsson2277( BR); c.  20 kmNNE of Libreville,  11.III.1987, fr.,  J.M. Reitsma& B. Reitsma3142( LBV, WAG);  Crystal Mountains N.P.,  8 kmon road from Kinguélé to Tchimbélé,  26.III.2013, imm.fr.,  Wieringa et al. 7801( WAG).   Moyen-Ogooué: Mboumi. 0°18–0°30S/10°45–10°48E,  16.I.2000, fl.,  Champluvier6019( BR, K, WAG).   Ogooué-Lolo: Chantier Bambidie, c.  52 kmon the road to Okondja-Lelama, along Sebe river,  31.X.2005, fl.,  Sosef et al. 2122( BR, LBV, WAG).   OgoouéMaritime: Région du Lac Alombié, ±  7 kmau N de Mpaga,  18.X.2014, buds,  Lachenaud et al.2007( BRLU, LBV, MO).   Woleu-Ntem: SEEG road near Tchimbélé, pylone 7,  6.II.2008, buds,  Dessein et al. 1724( BR, LBV, WAG);  Angoum,  28.VII.1933, fl.,  Le Testu9198( BM, P);  Monts de Crystal, Tchimbélé,  14.IV.2006, imm.fr.,  Leal et al. 1109( BR, LBV).   Fig. 6. –  Sabicea couteroniiO. Lachenaud, Zemagho & Sonké: A.Node with inflorescences; B.Fruiting stem; C.Mature infructescence.  Sabicea dichrosepalaO. Lachenaud, Zemagho & Sonké: D.Inflorescence; E.Mature infructescence. [  A:  Sonké& Zemagho 6341;  B–C:  Sonké& Zemagho 6334; D: Bidault et al. 4401;  E: Dessein et al. 2028] [Photos:  A–C: B. Sonké; D: E. Bidault;  E: S. Dessein]   Table 1. –Diagnostic characters between  Sabicea couteroniiO. Lachenaud, Zemagho & Sonké,  S. dichrosepalaO. Lachenaud, Zemagho & Sonké,  S. proselyta(N. Hallé) Razafim. et al.,  S. rubiginosaO. Lachenaud, Zemagho & Sonkéand  S. sanguinosa(N. Hallé) Razafim. et al.      S. couteronii   S. dichrosepala   S. proselyta   S. rubiginosa   S. sanguinosa   Indumentum of stems +/– appressed, buff, with straight & crisped hairs intermingled appressed, whitish, with straight hairs only appressed, whitish to brownish, with long straight & shorter uncinate hairs appressed, rufous-brown, with long straight & shorter uncinate hairs  hirsute, whitish, with straight hairs only   Leaf surface (in life) +/– flat +/– flat +/– flat +/– flat  bullate   Indumentum of leaves (upper side) mostly on veins, long and +/– appressed mostly on veins, short and appressed mostly on veins, short and appressed mostly on veins, short and appressed  uniform, long and hirsute   Indumentum of leaves (lower side)  buff, woolly and very dense(with additional straight appressed hairs on the veins) whitish, straight and appressed, mostly on veins whitish, straight and usually appressed (sometimes erect except on veins)  long rufous hairs mostly on veins + short erect whitish hairs all over whitish, straight and hirsute   Tertiary leaf veins (on lower leaf surface) raised, much stronger than 4° veins  nor or hardly raised, only slightly stronger than 4° veins raised, much stronger than 4° veins raised, much stronger than 4° veins raised, much stronger than 4° veins   Base of stipules not auriculate  auriculate not auriculate not auriculate not auriculate   Indumentum of stipules (outside) appressed, dense, uniform appressed, minute and very sparse appressed, dense at least in central part appressed, dense, uniform  hirsute, rather sparse, uniform   Colour of stipules pale green pale green pale green dark red-brown pale green / wine red   Inflorescences densely cymose  glomerulate at anthesis, laxer and cymose in fruit cymose, rather lax cymose or rarely glomerulate at anthesis cymose,+/– dense at anthesis and laxer in fruit   Peduncle 0.5–2.5 cm  0–0.3 cm 0.5–3.8 cm 0.3–3.5 cm 0.3–5 cm   Size of largest bracts 6–14 × 3–7 mm 7–8.5 × 2.5–4 mm 4.5–8 × 1.5–5 mm 4–11 × 1.3–3.5 mm 8–22 × 3–11 mm   Colour of calyx lobes uniformly pale green  pinkish-red at base and green at apex uniformly green to brownish green dark red (sometimes greenish/white at base) pale green / wine red   Size of calyx lobes 1.5–2.5 × 0.8–1.5 mm 2.5–4 × 1.5–2.3 mm 1.3–2 × 0.7–1.3 mm 1.5–3 × 0.5–1.2 mm 2.5–5 × 0.6–2 mm   Apex of calyx lobes rounded rounded obtuse/rounded obtuse/rounded acute   Indumentum of calyx lobes villose on both sides puberulous on both sides puberulous on both sides villose outside, puberulous inside hirsute on both sides   Inside of calyx tube villose sparsely and shortly pubescent villose glabrous glabrous / sparsely pubescent   Fruit colour  purplish-red (young) to blackish (mature) white greyish white greyish white greyish white   Granules in mesocarp present  absent present present present   Seed surface reticulate coarsely reticulate coarsely reticulate finely striolate finely striolate   Distribution SE Cameroon, central Gabon, SW Congo Republic Gabon (Cristal Mts & Chaillu massif) south Cameroon to Congo Republic west-central Gabon coastal Gabon    NIGERIA. Cross River State: Oban, 1911, buds,  Talbot228( BM, K);  New Ndebiji,  30.IV.1952, fl.,  Ejiofor FHI21883( FHI, K). 3698751554 1962-01-20 BR, K, P, WAG, YA Letouzey Cameroon au S de Zingui au S de Zingui 11 126 1 Reg. South 3698751327 1963-03-13 P, YA J. & A. Raynal Ebemwok Ebemwok 11 126 1 3698751558 1908-12-14 K Tessmann Campogebiet Bebai 11 126 1 3698751399 BM, G, K, P, WAG Zenker Bipindi Bipindi 11 126 1 3698751338 [1052,1452,1536,1555] BM, BR, K Zenker Bipindi Bipindi 11 126 1 3698751451 [801,1311,1562,1582] 1902-05-05 K Rudatis Abonando 11 126 1 Reg. Southwest 3698751356 1997-11-28 BRLU, WAG Obama Equatorial Guinea Monte Mitra Monte Mitra 11 126 1 Centro-Sur 3698751616 1969-02-25 K Sanford Oborobiko 11 126 1 3698751482 2001-08-11 BR, BRLU Sonke Akonangui Ayaguening 11 126 1 3698751452 2003-12-13 BR, BRLU, K Sonke 11 126 1 3698751586 1988-06-13 BR, K, WAG Dibata rte d'exploitation chantier SEMGE vers le 1 er pont sur Mitemele 11 126 1 Litoral 3698751582 2001-02-19 BRLU Lejoly de Sendje a Ongamnsok 11 126 1 3698751506 1998-01-09 BRLU N. Nguema & Lejoly rte de Nco vers Misobong au niveau de la grande cascade 11 126 1 3698751377 1999-02-26 BR Andersson & Nilsson Gabon Foret de Mondah on road Libreville-Cap Esterias 11 126 1 Estuaire 3698751446 1987-03-11 LBV, WAG J. M. Reitsma & B. Reitsma 11 126 1 3698751309 2013-03-26 WAG Wieringa et al Crystal Mountains N. P. 11 126 1 3698751492 2000-01-16 BR, K, WAG Champluvier Mboumi Mboumi 11 126 1 Moyen-Ogooue 3698751489 2005-10-31 BR, LBV, WAG Sosef et al along Sebe river Chantier Bambidie 14 129 1 Ogooue-Lolo 3698751303 2014-10-18 BRLU, LBV, MO Lachenaud et al. Region du Lac Alombie Ogooue- Maritime 14 129 1 3698751352 2008-02-06 BR, LBV, WAG Dessein et al SEEG road near Tchimbele 14 129 1 Woleu-Ntem 3698751663 [136,555,410,430] 1933-07-28 BM, P Le Testu Angoum Angoum 14 129 1 3698751339 2006-04-14 BR, LBV Leal et al Tchimbele Monts de Crystal 14 129 1 3698751341 [174,742,464,483] 1952-04-30 BM, K, FHI Talbot & Ejiofor FHI Nigeria New Ndebiji Oban 14 129 1 Cross River State 3698751662 1952-04-30 BM, K, FHI Talbot & Ejiofor FHI Nigeria New Ndebiji Oban 14 129 1 Cross River State