Paracephaelis sericea De Block
Creators: name: Block, Petra De
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Gentianales
Rubiaceae
Paracephaelis
Paracephaelis sericea

description: Paracephaelis sericea (Arènes) De Block
Figs 1D, 19
Taxon 64: 92 (De Block 2015).
Basionym
Homolliella sericea Arènes, Notulae Systematicae 16: 17, Pl. 4, 19–25 (Arènes 1960).
Type: MADAGASCAR – Toamasina Province, Alaotra-Mangoro Region, Moramanga District • forêt d’Analamazaotra; Feb. 1919; fl; Thouvenot 122; holotype: P [P00551271]; isotypes: BR [BR00000904508], P [P00551270]. See Note 1.
Other material studied
MADAGASCAR – Antsiranana Province, Sava Region, Andapa District • Anjialavabe, Ankiakabe, near Tsaralanto village; 1030 m a.s.l.; Feb. 2006; fl; Antilahimena, Randriamandimby & Falison 4610; BR, MO, P, TAN • Anjialavabe, Ankiakabe, forêt d’Antsahaberaoka, 11 km NW d’Anjialavabe; 1002 m a.s.l.; 21 Feb. 2007; fl; Rakotovao, Razakamalala, Ravelonarivo & Jacky 3703; BR, G n.v., P online, TAN • Anjanaharibe-Sud RS; 1116–1424 m a.s.l.; 21 Mar.–7Apr.1994; fr; Ravelonarivo, Rasoavimbahoaka, Rafaliarimanana, Rasitefanonirina & Raymond 29; K, MO, P, TAN • Anjanaharibe-Sud RS, commune Bealampona, quartier de Befingotra, village d’Andranotsarabe, suivant la route d’Andapa vers Bealanana, piste de l’est 1 km à côté droite du ruisseau Andranotsarabe; 890–1041 m a.s.l.; 14 Sep. 1994; fr; Ravelonarivo, Rabesonina & Ramainty 358; BR, K, MO, P, TAN • Doany, Tsaralanto, Andongozabe, Ankiakabe; 1293 m a.s.l.; 1 Mar. 2006; fl; Ravelonarivo, Patriode, Mobel & Germain 1680; BR, MO, P online, TAN. – Toamasina Province, Alaotra-Mangoro Region, Ambatondrazaka District • Didy, forêt de Tsarahonena environ 7 km de Didy; 1108 m a.s.l.; 14 Jan. 2010; fl; Andrianaivoravelona, Ralimanana, Rakotoarinivo, Rajaonarison, Rakotoroalahy & Ramaherimana 227; K n.v., P online, TAN n.v. • Mitanonoka, fir. Manakambahiny-Est; 18Jan.1963;fl; Laibosaka 12599-RN; P, TEF • Manakambahiny- Est; 3 Mar. 1950; fl; Ramanantoavina 1963-RN; BR, P, TAN • fir. Manakambahiny-Est, entre Laindrotra et Onibe, 5 km E de Manakambahiny-Est; 900 m a.s.l.; 19 Sep. 2002; fr; Ratovoson, Rakotondrajaona, Randrianasolo, Rasolohery, Razakanirina & Mananjara 679; BR, K, MO. – Toamasina Province, Alaotra-Mangoro Region, Amparafaravola District • Anony, N du pays Sihanaka; 3 Sep. 1937; fr; coll. ignot. (Herbier Jardin botanique de Tananarive) 2939; P. – Toamasina Province, Alaotra-Mangoro Region, Moramanga District • Sandrangato, PK 27 route d’Anosibe; 26 Oct. 1964; fl, fr; Abraham 187; TEF • Ambohibary, Ampitambe, Ambatovy, forêt d’Analamay, campement Mahatakatra; 1110 m a.s.l.; 15 Dec. 2004; fr; Andriamahefarivo, Antilahimena, Ranaivojaona & Edmond 41; BR, MO, P, TAN • Ambatovy Dynatec; 1115 m a.s.l.; 16 Jan. 2005; fl; Andriantiana 349; BR, MO, P • commune Andasibe, fkt. Menalamba, Ambatovy forest; 996 m a.s.l.; 16 Jan. 2005; fl; Antilahimena 3173; BR, MO, P, TAN • commune Ambohibary, fkt. Ampitambe, Vavanaomby forest; 1025 m a.s.l.; 11 Feb. 2007; fl; Antilahimena, Edmond & Tojoniaina 5277; MO n.v., P online, TAN n.v. • commune Ambohibary, fkt. Ampitambe, Sahaviana forest; 987 m a.s.l.; 22 Feb. 2007; fl; Antilahimena & Edmond 5389; MO n.v., P, online TAN n.v. • commune Andasibe, fkt. Menalamba, Ambatovy, lac Amparihihambana; 1116 m a.s.l.; s.dat.; fl; Antilahimena, Edmond & Razadindasy 5474; MO n.v., P online, TAN n.v. • commune Ambohibary, fkt. Ampitambe, Andranovery forest, Ambatovy; 995 m a.s.l.; 21 Oct. 2007; fr; Antilahimena & Marcelin 5857; MO n.v., P online, TAN n.v. • Andasibe, Menalamba, forêt d’Analamay; 1142 m a.s.l.; 6 Jun. 2007; fr; Bernard, Antilahimena & Marcelin 524; BR, MO, P, TAN • Ambatovy; 996 m a.s.l.; 24 Oct. 2007; fr; Bernard 692; BR, MO, P, TAN, TEF • Ambohibary, Ampitambe, Ambatovy, zone de défrichement 22; 1093 m a.s.l.; 26 Apr. 2010; fr; Bernard, Ratodimanana, Ramahenina, Edmond & Randrianasolo 1556; MO n.v., P online, TAN n.v. • Befoza, Perinet; 14 Jun. 1950; fr; coll. ignot. 2610-SF; P, TAN, TEF • Sahamaloto-Perinet; 10 Jul. 1951; fr; coll. ignot. 3836-SF; P, TEF • Sahamaloto-Perinet; 2 Sep. 1952; fr; coll. ignot. 5748-SF; P, TEF • Menalamba, Perinet; 27 Feb. 1959; fl; coll. ignot. 14958-SF; BR, K, P, TEF • Sahamaloto, Perinet; 18 Jun. 1955; fr; coll. ignot. 15012-SF; P, TEF • Analamazaotra, village le plus proche Perinet; 800 m a.s.l.; 6 Apr. 1958; fr; coll. ignot. 17946-SF; P, TEF • fir. Marovoa, au bord du ruisseau Andrevodrevoka, village le plus proche Sakalava-Ambany, forêt d’Ankeramadinika; 1100 m a.s.l.; 19 Sep. 1964; fr; coll. ignot. 21855-SF; K, P, TEF • réserve Sandrangato, PK 27 route d’Anosibe; 900 m a.s.l.; 26 Oct. 1964; fr; coll. ignot. 21948-SF; BR, G, K, P • station forestière d’Analamazaotra, environs de la parc des orchidées; 880 m a.s.l.; 23 Feb. 1999; fl; De Block & Rakotonasolo 849; BR, G, K, MO, P, TAN, WAG • ibid.; 880 m a.s.l.; 23 Feb. 1999; fl; De Block & Rakotonasolo 850; BR, K, MO, P, TAN • Analamazaotra; 19 Apr. 2010; fr; De Block, Groeninckx & Razanatsoa 2532; BR, K, MO, TAN, WAG • forêt d’Analamazaotra; Oct. 1923; fl; Louvel 182; P • Andasibe, Menalamba, forêt d’Antsampanandrano; 1114 m a.s.l.; 4 Jun. 2007; fr; Miandrimanana, Ravelonarivo & René d’Ampitambe 224; MO n.v., P online, TAN n.v. • forêt d’Analamazaotra; 800 m a.s.l.; Feb. 1912; fl; Perrier de la Bâthie 8621; P • Phelps Dodge project site, ca 15 air-km NE of Moramanga, ca 11 km E of Antanambao, between Ambatovy-Sud and Analamy-Est, Torotorofotsy River, Berano; 1000 m a.s.l.; 20 Feb. 1997; fl; Rakotomalaza, Razafimanantsoa & Andriatsiferana 1152; MO, P • Ambohibary, Ampitambe, Andranovery, Ambatovy, clearing zone 5; 1000 m a.s.l.; 13 Feb. 2008; fl; Rakotondrafara, Rakotondrajaona, Rabearivanona, Ratovomanana & Rajerison 586; MO n.v., P online, TAN n.v. • ibid.; 985 m a.s.l.; 15 Feb. 2008; fl; Rakotondrafara, Rakotondrajaona, Rabearivanona, Ratovomanana & Rajerison 628; MO n.v., P online, TAN n.v. • ibid.; 1024 m a.s.l.; 4 Mar. 2008; fl; Rakotondrafara, Rakotomazava, Ratovomanana, Raymond & Kotosoa 685; MO n.v., P online, TAN n.v. • RN 2, PK 6 after Moramanga; 900 m a.s.l.; 21 Aug. 1999; fr; Rakotonasolo 94; BR, K • Ambatovy, SW d’Ampitambe; 950–1000 m a.s.l.; 5 Oct. 2002; fr; Rakotonasolo 425; BR, TAN • Ambohibary, Ampitambe, Ambatovy, Befandrotrarana, by pass; 995 m a.s.l.; 21 Feb. 2010; fl; Ramahenina, Ravelonarivo & Razafimelison 12; MO n.v., P online, TAN n.v. • commune Amboasary, fkt. Antsily, village Mangabe, forêt d’Ampahatra; 987 m a.s.l.; 13 Nov. 2012; fl; Ramahenina, Randrianaivo, Rasoazanany, Razanakoto & Randriamialisoa 149; MO n.v., P online, TAN n.v. • Perinet, Sahamaloto; 18 Feb. 1948; fl; Ratovoarison 1337-RN; P, TAN • Befoza, Perinet; 27 May 1994; fr; Ravilonombiara s.n.; P • Ambohibary, Antsily, Andakana, forêt d’Ampahatra; 923–942 m a.s.l.; 11 Sep. 2012; fl; Razakamalala & Randrianaivo 7045; MO n.v., P online, TAN n.v. • Ambatovy forest; 1100 m a.s.l.; 1 Feb. 2006; fl; Rogers & Antilahimena 1004; BR, MO • ca 19 km S of Moramanga along road to Anosibe An’ala, ca 2 km N of road; 16 Feb. 1991; fl; Schatz, Spargur, Hines & Thomas 3162; K, MO, P, TAN • Mantadia, PK 15, site of graphite mine; 1058 m a.s.l.; 21 Jan. 2006; fl; Tosh, De Block & Rakotonasolo 248; BR, G, K, MO, P, TAN, WAG. – Toamasina Province, Analanjirofo Region, Mananara Avaratra District • forêt d’Ibanda; 500 m a.s.l.; 20 Jul. 1990; fr; Raharimalala 1077; P. – Maroantsetra District • environs de la baie d’Antongil, Antandrokolaka, entre les bassins de la Rantabe et de la Fananehana; Feb. 1954; fl; Capuron 9040-SF; K, MO, P, TEF. – Vavatenina District • Sahatavy; 25 Apr. 1960; fr; Laibosaka 10950-RN; MO, P, TEF. – Atsinanana Region, Toamasina II District • RN 3, Mangabe; 13 Feb. 1952; fl; Botoalma 3724-RN; BR, K, MO, P, TAN • RNI 1, Betampona, 1 km de la poste de Rendrirendry, piste principale, fkt. Andrantabe, fir. Ambodiriana; 20 Mar. 1999; fl; Iambana, Bernard & Birkinshaw 138; MO n.v., P online, TEF n.v. – Vatomandry District • Ambalabe, forêt de Vohibe, piste sortant du plot vers Ambinanin’i Sahamahirana; 644 m a.s.l.; 19 Sep. 2010; fr; Raharimampionona, Rasoaviety & Lezafy 365; MO n.v., P online, TAN n.v. • Ambalabe, Ambinanindrano II, Vohibe forest, WSW of Foara Toby, along trail towards Tsitondroina waterfall; 667 m a.s.l.; 20 Nov. 2013; fl; Randrianasolo, Razanatsima, Foara, Zafindrafeno & Mamy 1453; MO n.v., P online, TAN n.v. • Ambalabe, Ambinaninandro II, E de Toby Foara; 589 m a.s.l.; 11 May 2006; fr; Razanatsima 106; MO n.v., P online, TAN n.v. • Ambalabe, Ambinanindrano II, forêt de Vohibe, rivière Vakoanina; 697 m a.s.l.; 21 Aug. 2015; fr; Razanatsima 1419; MO n.v., P online, TAN n.v. • Ambalabe, Ambinanindrano II, Vohibe, Vohibe forest; 609–648 m a.s.l.; 19 Apr. 2010; fr; Rothrock, Kuhlman, Rakotoarivelo, Rasoarivety, Zafindrafeno, Yhomad & Florentin 339; BR, MO. – Mahajanga Province, Sofia Region, Mandritsara District • Tsaravilona Amparihy, Makira, suivant une ligne de crête vers le NE; 1302 m a.s.l.; 26 Feb. 2008; fr; Ravelonarivo, Gerard & Rasoanaivo 3032; BR, MO, P, TAN. – Fianarantsoa Province, Atsimo-Atsinanana Region, Vondrozo District • Vondrozo forest, along main road; 578 m a.s.l.; 5 Feb. 2006; fl; De Block, Tosh & Rakotonasolo 1994; BR, MO, P, TAN, UPS. – Ihorombe Region, Ivohibe District • Ivohibe forest, 7 km from Ivohibe village; 801 m a.s.l.; 31 Jan. 2006; fl; Tosh, De Block & Rakotonasolo 301; BR, MO, P, TAN. – Vatovavy-Fitovinany Region, Mananjary District • Ambodiramiavona; 20 Jul. 1956; fr; coll. ignot. 14733-SF; P, TEF. – Toliara Province, Anosy Region, Taolagnaro District • RNI 11, Andohahela, forêt humide prés du village Taviala-Andohavondro S d’une rivière Antsororoka, commune Ankaramena; 175–200 m a.s.l.; 29 Jun. 1995; fl; Eboroke 1043; BR, MO, P online.
Description
Tree, 5–16 m tall, dbh to 35 cm; pubescence tawny. Young shoots dark brown but rapidly becoming corky and reddish brown, densely covered with short erect hairs; older branches brown, pale or reddish brown, flaking, glabrescent. Petioles 1–3 cm long, densely covered with short erect hairs. Leaf blades obovate or, more rarely elliptic, ovate or broadly obovate, 7–21 × 4.5–12 cm, coriaceous, drying brown to dark brown above and somewhat paler below, upper surface glossy, moderately to densely covered with minute erect hairs (with pubescence on midrib and secondary veins denser), or, rarely, glabrous (with pubescence restricted to midrib and sometimes secondary veins), lower surface densely covered with short erect hairs (with pubescence on midrib and secondary veins identical to that on blade or appressed rather than erect); base cuneate, more rarely obtuse to rounded; tip acuminate (often abruptly), acumen narrow, 0.5–1.5 cm long; hair tuft domatia often present; 8–10 secondary veins on each side of midrib, raised on both surfaces; higher order venation inconspicuous above, visible below. Stipules triangular or ovate, 8–30 mm long, gradually tapering into an acute tip or, more rarely, with short awn 1–2 mm long, outer surface densely covered with short erect hairs, inner surface glabrous with row of colleters at the base; yellow or brownish mucus often present on youngest stipule pair (when dried). Inflorescences sessile, 1.5–7 × 3–9 cm, with 15 to numerous flowers; inflorescence parts densely covered with short erect hairs; first order axes 0.3–4 cm long; higher order bracts with stipular parts reduced or absent, foliar parts narrowly triangular and vaulted, 2–6 mm long (up to 10 mm long in second order bracts); bracteoles on pedicel just below ovary, opposite, stipular parts absent, foliar parts triangular, 1–2 mm long, tips acute. Flowers sessile to shortly pedicellate, pedicels 0–2 mm long (rarely up to 5 mm long in case of reduction). 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 2–5 mm long; lobes broadly ovate, 0.5–1.5 mm long, often keeled, margins ciliate, tips rounded, obtuse, acute to minutely acuminate. Corolla tube 0.6–1.7 cm long, inner surface moderately to densely covered with long erect hairs in upper half; lobes 5–8 mm long, margins ciliate. Anthers 5–6.5 mm long, completely exserted from corolla tube at anthesis; filaments 1–1.5 mm long. Ovary 1.5–2.5 mm long, longitudinally ribbed (when dried), densely covered with short erect hairs; per locule 4–7 ovules arranged at periphery of placenta attached to middle of septum. Style and stigma 12–34 mm long, exserted for 6–17 mm; style moderately covered with long erect hairs for 6–7 mm below papillate zone; stigmatic lobes 7–16 mm long. Fruits ovoid to subspherical, longitudinally ribbed (when dried), 10–12 × 8–11 mm, densely covered with short erect hairs; fruit wall well-developed with multi-layered anastomosing network of sclerified vascular bundles; pyrenes hemi-ovoid, ca 7.5 × 5 mm, thickly crustaceous, with rounded base, shortly acuminate tip, small adaxial opening just above the middle and prominent 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(–10) per fruit, 4.5–5 mm × 3.5–4 mm.
Distribution
Mostly collected from the Moramanga area, but present along the entire east coast. Present in: Andapa District, Sava Region (Antsiranana Province); Ambatondrazaka, Amparafaravola and Moramanga Districts, Alaotra-Mangoro Region, Mananara Avaratra, Maroantsetra and Vavatenina Districts, Analanjirofo Region, and, Toamasina II and Vatomandry Districts, Atsinanana Region (Toamasina Province); Mananjary District, Vatovavy-Fitovinany Region, Ivohibe District, Ihorombe Region, and, Vondrozo District, Atsimo-Atsinanana Region (Fianarantsoa Province); Taolagnaro District, Anosy Region (Toliara Province); Mandritsara District (eastern part), Sofia Region (Mahajanga Province) (Fig. 23D).
Habitat and phenology
Mid-elevation or lower montane humid forest (500–1450 m a.s.l.), rarely low-elevation humid forest (Toliara: Andohahela: 175–200 m a.s.l.); on laterite soil. Flowers: October–March, flowering peak in February; Fruits: April–December. The single specimen collected from Toliara (Andohahela) flowers in June.
Vernacular names and uses
Most commonly this species is indicated with the names molotrangaka (e.g., Antilahimena et al. 3173) or molotrangaka be ravina (“molotrangaka with large leaves”, e.g., coll. ignot. 17946-SF). Other vernacular names are: afatra (coll. ignot. 21855-RN); ampitsikahitra à grandes feuilles (Louvel 182); fisatendro (Thouvenot 122); halampona (Rothrock et al. 339); kisaka (Andrianaivoravelona et al. 227); ritsikaludambo (Botoalma 3724-RN); sadodoka à grandes feuilles (Laibosaka 12599-RN); toalanana(na) (Abraham 187, coll. ignot. 21948-RN); vandrikala (Capuron 9040-SF); vanopotsy (Laibosaka 10950- RN); voantalanana (Ramanantoavina 1963-RN); voantalanana fotsy (Ratovoson et al. 679). The species is used for firewood (coll. ignot. 14958-SF, coll. ignot. 21855-SF), tool handles (Ratovoson et al. 679), and wood for construction (Abraham 187, coll. ignot. 15012-SF, coll. ignot. 21948-SF).
Provisional IUCN assessment
Least Concern: LC. This assessment is based on 68 collections with detailed locality data, collected between 1912 and 2015. The EOO of P. sericea is estimated to be 98 231 km 2, far exceeding the upper limit of any threat category under criterion B1. The AOO is 184 km 2, which complies with the Endangered category under criterion B2. The species occurs in ca 20 locations, which far exceeds the upper limit of any threat category under subcriterion ‘a’ of criterion B2. However, over 20% of the specimens of P. sericea were collected at Ambatovy, a location which will disappear within the next thirty years as a result of mining (see P. pauciflora sp. nov. for details). This will have a negative effect on the number of locations and the AOO, but not on the EOO. Paracephaelis sericea is present in several protected areas, notably the Andasibe-Mantadia, Zahamena, and Andohahela National Parks, the Anjanaharibe- Sud Special Reserve, the Betampona Natural Reserve, the Vohibe Forest New Protected Area, and the Vondrozo Forest Reserve. Throughout Madagascar outside protected areas, clearing of forest continues at a rapid pace (Harper et al. 2007). The main causes are subsistence farming, bushfires, and grazing by cattle. Mining also impacts the natural vegetation (Cardiff & Andriamanalina 2007), e.g., graphite mining in Mantadia (https://tirupatigraphite.co.uk/madagascar-projects/), nickel and cobalt mining in Ambatovy (http://www.ambatovy.com). Unfortunately, the protected areas in which P. sericea occurs are not spared from degradation resulting from anthropogenic factors. They suffer from land clearing for subsistence farming, cattle grazing, human settlement (e.g., Zahamena: Hannah & Boltz 2003) or artisanal mining (e.g., Anjanaharibe-Sud: Garreau & Manantsara 2003). Furthermore, logging, production of charcoal, collection of non-timber forest products, and hunting take place (Nicoll & Langrand 1989; Britt et al. 2003; Fenn 2003; Garreau & Manantsara 2003; Hannah & Boltz 2003; Rasolofoson et al. 2007; Dolch 2008; Rakotoarivelo et al. 2015). The remote location of some protected areas, such as Zahamena, Makira, and Anjanaharibe-Sud, and the limited resources for their management are also negative factors. The main threat to P. sericea is the destruction of its habitat, notably for subsistence farming and the abovementioned factors. We therefore infer a reduction in the extent and quality of its habitat. In the future, there will also be a reduction in number of locations (Ambatovy). However, the species has a large EOO and occurs in a high number of locations, some of which have more intact vegetation. Therefore, P. sericea is assessed as Least Concern.
Notes
1. Arènes (1960) cited the holotype as “ Perrier 122 ”. The holotype is in fact a collection made by Thouvenot but donated to the Paris herbarium by Perrier (Thouvenot in Perrier de la Bâthie 122). One isotype was donated by Fauchère (Thouvenot in Fauchère 122). This last specimen bears a label from the Service de Colonisation listing Ramamantoavolana as collector and a printed label saying “Thouvenot 1919”. Another specimen bears only the indication “ Service de Colonisation 122 ” (BR). According to Dorr (1997), Thouvenot undertook collecting expeditions for the Service de Colonisation together with Fauchère and Ramamantoavolana.
2. Homolle recognized this species as new and wanted to name it “ Maireana sericea ”, but she never finalized the description. Since the name Maireana already existed for a genus of the Chenopodiaceae Vent., Arènes (1960) named the new genus for Homolle (Homolliella).
3. In his unpublished Révision des Rubiacées de Madagascar et des Comores, Capuron (1973: 175) considered Paracephaelis to be a section of the genus Tarenna. In this section he also placed the type species of Homolliella and introduced the combination “ Tarenna sericea ”, a combination which was never formally published.
4. The vernacular names molotrangaka or molotrangaka be ravina are also used for Robbrechtia grandifolia De Block, another species of Pavetteae characterized by large leaves, stipules and calyces, and which overlaps in distribution and habitat with P. sericea (De Block 2003).
5. In some specimens the corolla tubes are slit longitudinally over the whole length at anthesis (e.g., Antilahimena et al. 4610).
description: Published as part of Block, Petra De, 2022, Monograph of the western Indian Ocean genus Paracephaelis (Rubiaceae - Pavetteae), with description of thirteen new species, pp. 1-99 in European Journal of Taxonomy 801 on pages 72-77, DOI: 10.5852/ejt.2022.801.1685, http://zenodo.org/record/6358810