Campylospermum occidentalis Biss., 2013

Bissiengou, P., Chatrou, L. W., Wieringa, J. J. & Sosef, M. S. M., 2013, Taxonomic novelties in the genus Campylospermum (Ochnaceae), Blumea 58 (1), pp. 1-7 : 6

Campylospermum occidentalis Biss. , sp. nov. — Fig. 2 ; Map 4

Diagnosis — A species similar to C. paucinervatum Sosef , but leaf blade papery, with an acuminate apex, entire to serrulate margin and 7–11 main lateral veins on either side of the midrib; inflorescence lax, 4–8(–12) cm long, with 1–4(–6) racemes of 1–7(–11) cm long; pedicels 10–15 mm, articulating at 2–5 mm from the base.

Type. Haegens & v.d. Burgt 106 (holo WAG; iso LBV), Gabon, Ogooué-Maritime, Rabi-Kounga, road to Divangui , S1°54', E9°55', 6 Dec. 1993 .

Treelet up to 4 m tall. Stipules caducous, 2–3 mm long. Leaves: petiole 2–5 mm long; leaf blade narrowly elliptic to narrowly elliptic-obovate, 6–15 by 1.5–4.5 cm, base cuneate, apex acuminate, papery, margin entire to serrulate, glossy dark green above, paler green below; midrib slightly prominent above, prominent below, main lateral veins 9–10 mm apart, 7–11 on either side, curved upward to run parallel to the margin, tertiary venation distinct on both sides, scalariform, running perpendicular to the midrib thus causing the formation of a series of slightly prominent intermediate lateral veins. Inflorescences terminal, lax, 4–8(–12) cm long; peduncle slender; racemes 1–4(–6), 1–7(–11) cm long, held ± horizontally, not seldom with secondary branches; pairwise scales at the base of peduncle absent; bracts early caducous; cymules (5–) 10–15 mm apart, 1–2(–3)-flowered. Flowers: pedicel 4–10(–15) mm, articulated at 1–6 mm from the base; sepals ovate, in flower 5–7 by 2–3 mm, greenish yellow, in fruit 6–7 by 3–3.5 mm, persistent and accrescent, red; petals obovate, 5–11 by 4–7 mm, cuneate at base, rounded to emarginate at apex; stamens 10, yelloworange, filaments less than 1 mm long, anthers 3–4 mm long; ovary c. 2 mm wide; style slender, curved, c. 4 mm long. Fruits: receptacle a ± flattened-globose shape, c. 3 mm wide, red; drupelets 1–3 well developed per receptacle, ellipsoid, c. 8 by 5 mm, orange to orange-red at maturity; cotyledons incumbent, similar in size.

Distribution — Endemic to Gabon, only found in the coastal plain, in the Ogooué-Maritime (Rabi-Kounga) and Estuaire (Mondah forest and Bikele) provinces.

Ecology — Primary and secondary,moist forest,near swampy areas; on sandy soil; at 5–30 m altitude.

Phenology — Flowers collected from August to November, coinciding with the end of the long dry season and start of the main rainy season; mature fruits from November to December.

IUCN conservation status — VU. B1ab(ii, iii, iv). EOO = 5959 km 2, AOO = 3388 km 2, locations = 4 (cell width = 29.10 km). This species seems to have a disjunct distribution, but this is uncertain because the area between the two occupied areas is not well explored. In a situation involving a disjunct distribution the sliding scale grid size method leads to an overly large estimation of especially the AOO. Some of the occurrences in the vicinity of the capital Libreville are under threat of habitat destruction due to urbanization and overexploitation. This is likely to lead to a decline in the area of occupancy and/or number of populations or even extent of suitable habitat and hence we propose the category ‘Vulnerable’.

Additional material. GABON, Estuaire: A.M. Louis 1201 ( WAG),secondary forest ± 17 km E of Libreville, S of Bikelé village, N0°23' E9°35', 7 Dec. 1983 (fr); Bissiengou 815 ( LBV, WAG), Mondah forest,parcelle des conservateurs, N0°35' E9°20', 10 Nov. 2009 (fl); Breteler & J.J.F.E. de Wilde 386 ( BR, C, K, LBV, MO, P, PRE, SRGH, WAG), Mondah forest , 25 km along the road Libreville-Cap Esterias , N0°32' E9°23', 5 m, 2 Sept.1978 (fl); de Saint Aubin 2076 (P), 18 km E de Libreville,c. N0°24' E9°34', Oct.1961 (fl); Reitsma 1328 ( MA, WAG), between Cap Santa Clara and Cap Esterias, N0°34' E9°22', 15 Aug. 1985 (fl); Wilks 1632 ( MO, WAG), Forêt de Mondah , N0°35' E9°20', 16 Sept. 1987 (fl, fr); Wilks 2090 ( LBV, MO, P, WAG), Nyonyie survey, around 1600 m on transect S, S0°02.9' E9°23.0', 3 July 1990 (fl, fr); Wilks 2097 ( MO, WAG),Nyonyie survey, 2710 m on transect S, S0°03.5' E9°23.0', 4 July 1990 (fl). Ogooué-Maritime: Breteler 10161 ( LBV, WAG), Rabi-Kounga, Echira road, c. S2°00' E9°50', 27 Oct. 1991 (fl); J.J.F.E. de Wilde 9725 ( WAG), 1 km on the road Rabi-Divangui, S1°54' E9°53', 25 Nov. 1989 (fr); Schoenmaker 135 ( WAG), Rabi-Kounga, direction Echira, c. S1°59' E9°51', 11 Nov. 1991 (fl).

Figures

Map 4 Distribution of Campylospermum occidentalis Biss. Background indicates altitude.

Fig. 2 a. Campylospermum gabonensis Biss.; b. C. gabonensis subsp. australis Biss.; c. C. glaucifolium Biss. d. C. occidentalis Biss. (a: Breteler 13124; b: Wieringa 2852; c: J.J. de Wilde 10165; d: Haegens 106; all holo WAG).