Paracephaelis grandifructa De Block, 2022

Block, Petra De, 2022, Monograph of the western Indian Ocean genus Paracephaelis (Rubiaceae - Pavetteae), with description of thirteen new species, European Journal of Taxonomy 801, pp. 1-99 : 45-48

Paracephaelis grandifructa De Block sp. nov.

urn:lsid:ipni.org:names:77260709-1

Figs 3 , 11

Diagnosis

Differing from Paracephaelis capitulifera sp. nov. by having larger fruits (15–20 × 10–15 mm vs 10–13 × 8–10 mm), hair tuft domatia (vs domatia absent), stipules with acute tips or more rarely acuminate with awn up to 2.5 mm long (vs acuminate with needle-like awn 1.5–4 mm long), longer calyx tubes (6.5–12 mm vs 3–8 mm long), shorter bracteoles (1.5–2.5 mm long, with acute tips vs 3–3.5 mm long, with acuminate tips), and calyx lobes with rounded to obtuse tips (vs acuminate, reflexed tips).

Etymology

The species epithet is based on the robust fruits.

Type material

MADAGASCAR – Toamasina Province, Analanjirofo Region, Mananara District • commune Vanono , fkt. Anjian’ny Madiorano , suivant la piste vers Ambodimanga Sahavalanana, à environ 1 km de vol d’oiseau SE d’Anjian’ny Madiorano; 834 m a.s.l.; 21 Jul. 2007; fr; Ravelonarivo et al. 2570; holotype: MO; isotypes: BR[BR0000022757630], P[P05402966], TAN .

Other material studied

MADAGASCAR – Toamasina Province, Alaotra-Mangoro Region, Moramanga District • Phelps Dodge project site, ca 15 air-km NE of Moramanga, ca 11 km E of Antanambao, Ambatovy-Sud ; 975 m a.s.l.; 15 Feb. 1997; fl; Andriatsiferana et al. 2148; MO, P . – Analanjirofo Region, Soanierana-Ivongo District • Andapafito, Iampirano, Ambatovaky RS, 4 km S of village; 520 m a.s.l.; 14 Dec. 2003; fl; Rakotonasolo, Beentje, Ralimanana & Rakotoarinivo 700; BR, K, P online, TAN . – Vavatenina District • Ambohibe, Ambatoharanana, Moango , le long de la piste vers Antevibe, Zahamena PN; 697 m a.s.l.; 15 Jul. 2004; fr; Andriamihajarivo, Ratovoson, Andrianjafisoa & Rapaoly 309; K, MO, P online • Beranomaso, fir. Sahatavy ; 16 Jan. 1958; fl; Ramarokoto 9466-RN; P online, TEF . – Antananarivo Province, Vakinankaratra Region, Ambatolampy District • 16.2 km SE de Tsinjoarivo, forêt d’Ankilahila , le long de la rivière d’Andrindrimbola ; 1450 m a.s.l.; 21 Jan. 1999; fl; Messmer & Andriatsiferana 748; G, K, P online . – Fianarantsoa Province, Vatovavy-Fitovinany Region, Ifanadiana District • Ranomafana PN, Vohipara , 38.3 km NE of Fianarantsoa; 1100 m a.s.l.; 2 Nov. 1997; fl, fr; Davis, Andriantiana, Gower & Malcomber 1041; BR, K, P online, TAN • Ranomafana PN, parcelle 3 , S of RN 25 at 7 km W of Ranomafana; 950–1150 m a.s.l.; 7 Oct. 1993; fr; Solo & Randrianasolo 25; BR, K, MO, P, TAN .

Description

Tree, 4–15 m tall, dbh to 20 cm, more rarely large shrub; pubescence tawny. Young shoots reddish brown, densely covered with short erect hairs; older branches reddish brown, often flaking, glabrescent. Petioles 1.2–2.2 cm long, densely covered with short erect hairs. Leaf blades occasionally anisophyllous (Solo & Randrianasolo 25; Rakotonasolo et al. 700), elliptic, somewhat obovate or somewhat ovate, 5–20 × 2.5–9 cm, coriaceous, drying brown and hardly discolorous, upper surface somewhat glossy, moderately covered with short erect hairs (with pubescence on midrib and secondary veins somewhat denser), lower surface densely covered with somewhat longer erect hairs; base cuneate to obtuse; tip acuminate with acumen 0.5–2 cm long; hair tuft domatia present; 10–15 secondary veins on each side of midrib, raised below; higher order venation hardly visible above, somewhat raised below. Stipules triangular, keeled, gradually tapering into an acute tip or, more rarely, with short needle-like awn, outer surface densely covered with short erect hairs, inner surface glabrous with 2–3 rows of colleters at the base; sheath 8–12 mm long; awn, if present, up to 2.5 mm long. Inflorescences sessile, capitate, 1.5–2(– 4 in fruit) × 3–4(– 8 in fruit) cm, with 15–40 flowers; inflorescence parts densely covered with short erect hairs; first order axes 0.2–0.8 cm long; higher order bracts with stipular parts reduced or absent, foliar parts narrowly triangular and vaulted, faintly keeled, 3–5 mm long, tips acute; bracteoles at base of ovary, opposite, stipular parts absent, foliar parts triangular, 1.5–2.5 mm long, tips acute. Flowers sessile. Calyx densely covered with short erect hairs outside, inner surface densely covered with minute appressed hairs all over but most dense at the base; tube 6.5–12 mm long, longitudinally ribbed (when dried); lobes ovate, 1–2 mm long, faintly keeled, margins ciliate, tips obtuse to rounded. Corolla tube 12–20 mm long, inner surface unknown; lobes 5–12 mm long. Ovary ca 3 mm long, strongly ribbed longitudinally (when dried), densely covered with short erect hairs; per locule 7–14 ovules arranged at periphery of placenta attached to middle of septum. Style and stigma unknown. Fruits ovoid, 15–20 × 10–15 mm, strongly ribbed longitudinally (when dried), densely covered with short erect hairs; fruit wall well-developed, with multi-layered anastomosing network of sclerified vascular bundles; pyrenes sub-hemispherical, ca 9 × 8 mm, thin, crustaceous, with rounded base, rounded tip, small adaxial opening somewhat below the middle and faint longitudinal central ridge running from the apex to the top of the adaxial opening and continuing into a longitudinal depression below it. Seeds 4–8 per fruit, 4.5–5.5 × 3–4 mm.

Distribution

Restricted to eastern Madagascar. Present in: Moramanga District, Alaotra-Mangoro Region, and Soanierana-Ivongo and Vavatenina Districts, Analanjirofo Region (Toamasina Province); Ambatolampy District, Vakinankaratra Region (Antananarivo Province); Ifanadiana District, Vatovavy-Fitovinany Region (Fianarantsoa Province) ( Fig. 23A ).

Habitat and phenology

Mid-elevation humid forest; elev. 500–1450 m. Flowers: November–February; Fruits: July–November.

Vernacular names

Lelanangaka, molotrangaka (Andriatsiferana et al. 2148); voatalanina (Ramarokoto 9466-RN).

Provisional IUCN assessment

Vulnerable: VU B1ab(iii) B2ab(iii). This assessment is based on 8 herbarium specimens collected between 1958 and 2007. The EOO of P. grandifructa sp. nov. is estimated to be 8777 km 2, which complies with the Vulnerable category under criterion B1. The AOO is 32 km 2, which complies with the Endangered category under criterion B2. The species occurs in 6 locations, which complies with the Vulnerable category under subcriterion ‘a’ of criterion B2. Paracephaelis grandifructa sp. nov. occurs in the Ranomafana and Zahamena National Parks and the Ambatovaky Special Reserve. These protected areas suffer from clearing of forest for subsistence agriculture, grazing of cattle, human settlement (Zahamena), and artisanal gold mining (Ranomafana). Furthermore, illegal logging, production of charcoal, collection of non-timber forest products, and hunting take place ( Nicoll & Langrand 1989; Thompson & Evans 1992; Wright 1997; Hannah & Boltz 2003; Jones 2018; BirdLife International 2020a). Outside the protected areas, these threats are even more prominent. Because of the above-mentioned facts, a reduction in the extent and quality of the habitat of P. grandifructa sp. nov. is inferred. This fact, in combination with the low EOO and AOO and the low number of locations, qualifies P. grandifructa sp. nov. as Vulnerable.

Note

1. Paracephaelis grandifructa sp. nov. resembles P. capitulifera sp. nov. by the similar pubescence on vegetative and reproductive parts, the stipular sheaths of the same size, the capitate inflorescences, the sessile flowers, the well-developed calyx tubes and the large ovoid fruits. The two species differ by the shape of the tips of the stipular sheaths (usually acute, more rarely with short awn up to 2.5 mm long in P. grandifructa sp. nov. vs with needle-like awn 1.5–4 mm long in P. capitulifera sp. nov.), the absence/presence of hair tuft domatia (present in P. grandifructa sp. nov. vs absent in P. capitulifera sp. nov.), the shape and size of the bracteoles (1.5–2.5 mm long and tips acute vs 3–3.5 mm long and tips acuminate), the length of the calyx tube (6.5–12 mm vs 3–8 mm long), the shape of the tip of the calyx lobes (round to obtuse and not reflexed vs acuminate and reflexed) and the size of the fruits (15–20 × 10–15 mm vs 10–13 × 8–10 mm). Paracephaelis grandifructa sp. nov. occurs in mid-elevation humid forest, elev. 500–1150 m, whereas P. capitulifera sp. nov. occurs in high plateau and gallery forest, elev. 1200–1700 m.

2. Two specimens with (near-)mature flowers were seen online (P). In Ramarokoto 9466-RN, the corolla tube is ca 20 mm long and the corolla lobes 6–7 mm long. In this specimen, the corolla tubes are split longitudinally over their entire length. In Messmer & Andriatsiferana 748, the flowers are mature buds, with the corolla tube ca 12 mm and the corolla lobes ca 5 mm long. The flowers of these two specimens could not be studied.

Figures

Fig. 3. Seed and seed-coat of Paracephaelis grandifructa De Block sp. nov. A. Lateral view of seed, showing the elongate, shallow hilum. B. Transverse section through seed, showing embryo sac. C. Longitudinal section through seed, showing embryo sac and embryo. D. Seed-coat in surface view. E. Section through seed-coat on the abaxial side of the seed, showing plate-like thickenings along outer tangential and lateral walls of the exotesta cells. F. Section through seed-coat in the region of the hilum, showing elongation of the exotesta cells. Drawn by Mr A. Fernandez. From Solo & Randrianasolo 25. Abbreviations: en = endosperm; ent = endotesta; ext = exotesta; h = hilum; pl = placenta; sc = seed-coat.

Fig. 11. Paracephaelis grandifructa De Block sp. nov. A. Flowering branch. B. Stipules. C. Bracteole, ovary and calyx. D. Fruit. Drawn by Mr A. Fernandez. From Rakotonasolo et al. 700 (A–C) and Solo & Randrianasolo 25 (D).

Fig. 23. Distribution maps of Malagasy species of Paracephaelis. A. P. aristata De Block sp. nov. (black dot), P. bardotiae De Block sp. nov. (blue dot), P. capitulifera De Block sp. nov. (green dot), P. gautieri De Block sp. nov. (red dot), and P. grandifructa De Block sp. nov. (yellow dot). B. P. cinerea (A.Rich. ex DC.) De Block (black dot). C. P. longipedicellata De Block sp. nov. (black dot), P. orientalis De Block sp. nov. (blue dot), P. pauciflora De Block sp. nov. (green dot), P. ranirisonii De Block sp. nov. (red dot), and P. seyrigii De Block sp. nov. (yellow dot). D. P. russata De Block sp. nov. (black dot), P. sambavensis De Block sp. nov. (blue dot), P. saxatilis (Scott Elliot) De Block (green dot), P. sericea (Arènes) De Block (red dot), and P. tiliacea Baill. (yellow dot).