Polyscias bernardiana Lowry & Callm., 2020

Lowry Ii, Porter P., Callmander, Martin W. & Spichiger, Rodolphe, 2020, Polysciadis (Araliaceae) species nova e Madagascaria in honorem Luciani Bernardii felsinei nominata, Candollea 75 (1), pp. 107-114 : 109-113

Polyscias bernardiana Lowry & Callm. , sp. nov. ( Fig. 1 , 2 ).

Holotypus: MADAGASCAR. Reg. Alaotra-Mangoro [Prov. Toamasina]: Ambatovy, NE of Moramanga, just below Ambatovy mine pumping station , 18°50'19"S 48°19'20"E, 1080 m, 20.IV.2009, y.fr., Lowry 7065 ( MO [6 sheets: acc. no. MO-6564638 , MO-6564639 , MO-6564640 , MO-6564641 , MO-6564642 , MO-6564643 ]! ; iso-: G [5 sheets: G00341883 ]!, K [5 sheets]!, P [5 sheets: P00967621 , P00967622 , P00967623 , P00967624 , P00967625 ]!, TAN!).

Haec species quoad habitum monocaulem caule in foliorum fasciculum grandem ac inflorescentiam terminalem desinente atque flores fructusque carpellis stylisque 8 ad 10 (ad 12) praeditos Polysciadem duplicatam (Thouars ex Baill.) Lowry & G.M. Plunkett arctius simulans, sed ab ea pedicellis proxime infra ovarium manifeste articulatis (vs. inarticulatis) atque foliis foliolis auxiliaribus ad axillas foliolorum principalium carentibus (vs. eis saepe praesentibus) distinguitur.

Tree, unarmed, 7–18 m tall, 10–30 cm dbh, monocaulous or rarely sparsely branched at top, hermaphroditic, evergreen. Leaves imparipinnately compound, 55–95 cm long. Leaflets 15 to 21, lateral ones opposite, blades dark green above, venation lighter, slightly paler beneath, venation darker in vivo, usually shiny above in sicco, thick chartaceous, elliptic to broadly elliptic, ovate or obovate, (6–)6.5–11 × (9–) 13–21 cm (proximal ones usually smaller), glabrous, secondary veins 7 to 13 per side, often with inter-secondaries, distinctly raised above, slightly less so beneath, tertiary venation usually visible, often impressed above, raised beneath, base broadly cuneate to nearly rounded, lateral blades usually asymmetric, margins entire, minutely revolute, apex rounded or broadly acute; petiolules 3– 15 mm long, 1–3.5 mm in diam.; rachis distinctly articulated at petiolule bases; petiole (4–) 5–15 cm long, 6–10 mm in diam., the clasping base with scattered circular lenticels, rarely with a slightly scarious margin to 1 mm wide. Inflorescence terminal, a panicle of umbellules, glabrous, primary axis erect, 8.5–16 cm long; secondary axes c. 10 to 25, c. 35 –50 cm long, proximal and distal ones nearly equal in length, each with 9 to 28 tertiary axes (peduncles) borne evenly throughout their length, terminating in an umbellule, the proximal ones often apparently abortive, leaving an evident scar; peduncles (2–) 4–8 cm long in flower, to 20 cm in fruit, distal ones progressively shorter, each with an evident bract scar at the base; umbellules with (6 to) 12 to 21 protandrous flowers, each subtended by a caducous bract that falls well before anthesis (not seen), leaving a small scar; involucre caducous, bracts broadly ovate; pedicels 1–12 mm long, 1 mm in diam. in flower, to 23 mm long in fruit, thickening to circa 1.5 mm in diam., glabrous, with an evident articulation at the point of insertion of the ovary. Calyx a narrow scarious rim, entire or slightly erose, tinged brownish purple. Corolla globose in early bud, hemispherical to somewhat ovoid at anthesis, c. 4–5 mm in diam., sometimes to 6 mm tall; petals 8–10(12), broadly to narrowly ovate or nearly triangular, c. 5 mm long, 3–3.5 mm wide, white to yellow. Stamens 8–10(12); filaments white, anthers pink to light purple. Ovary 8–10(–12)-carpellate, green, slightly darker than pedicels, glabrous, urceolate in flower, styles erect prior to anthesis, then spreading. Fruit a drupe, widely ovoid to globose, urceolate, 8 –10 mm high, 7–8 mm in diam., yellow green when immature, turning purple at maturity, contrasting with the whitish pedicel, glabrous, unribbed in vivo, distinctly ribbed in sicco, base and apex rounded, articulation forming a ring at the point of insertion of the pedicel, calyx in fruit a low rim c. 1.5 mm high, disc flat, whitish turning purple at maturity, styles 8–10(–12), arranged in an ellipse or occasionally a circle, divergent to nearly patent, c. 1 mm; pyrenes 8–10(–12), each 1-seeded.

Etymology. – The species epithet honors Luciano Bernardi (1920–2001), a 20TH century explorer-naturalist ( Fig. 3 ). He made c. 21,000 collections, duplicates of which are distributed in dozens of herbaria, including Geneva. Many of the expeditions led by Luciano Bernardi were conducted in extremely difficult and sometimes dangerous conditions. One can’t help but think that his drive to produce results and his willingness to subject himself to considerable risk were related to his wartime experience as an officer in the paratroops of the Italian army, of which he was so proud. He also prided himself on studying only difficult plant groups, looking for challenges and disregarding the beaten track. His broad and deep scientific knowledge and culture did not prevent him from being interested in other things: for example, he knew the general and anecdotal history of all the regions he explored. Bernardi also respected botanical tradition, to the point of almost exclusively using Latin for his notes and writings, even when it was not compulsory. Deeply rooted in European religious tradition, culture and philosophy, Luciano Bernardi’s existence is reminiscent of that of Guillaume d’Occam, the hero of Il nome della rosa [The Name of the Rose] by Umberto Eco, to which Luciano liked to refer (see SPICHIGER, 2002 for a more detailed necrology).

Distribution and ecology. – Polyscias bernardiana is predominantly known from medium altitude moist evergreen forest in east-central Madagascar between 800 to 1200 m elevation ( MADAGASCAR CATALOGUE, 2020), although two collections were made below 800 m in lowland moist evergreen forest, one from the Zahamena protected area (Rakotonandrasana 496) and another from the Corridor Ankeniheny Zahamena protected area (Razanatsima 212). Our new species appears to grow on ultramafic substrate at some localities within the Ambatovy mine concession but occurs primarily on soils derived from paragneiss and schist elsewhere in its range ( ROIG et al., 2012).

Conservation status. – Polyscias bernardiana is known from 18 localities along the eastern escarpment of Madagascar ( MADAGASCAR CATALOGUE, 2020), eight of which are encompassed within the protected areas network (Analamazaotra, Corridor Ankeniheny Zahamena, and Zahamena), whereas most or all of the others are in areas impacted either by habitat degradation and loss due to land clearing for subsistence agriculture or by forest removal associated with mining. With an EOO of c. 4,600 km ² and an AOO of 72 km ², P. bernardiana falls below the threshold for Endangered status under Criterion B of the IUCN Red List Categories and Criteria ( IUCN, 2012), but despite the extirpation of at least three subpopulations at Ambatovy, it nevertheless persists at 15 locations (sensu IUCN, 2012) with respect to the most serious threat, land clearing for agriculture, and is therefore assessed as Least Concern [LC].

Notes. – Polyscias bernardiana resembles P. duplicata (Thouars ex Baill.) Lowry & G.M. Plunkett from Madagascar and the Comoro Islands in almost always forming monocaulous trees (rarely sparsely branched) that terminate in a cluster of large leaves surrounding a large, globose inflorescence/infructescence. These two species also have flowers and fruits with 8 –10(– 12) carpels and styles (rarely as few as 6 or 7 in P. duplicata ) and generally 8 –10(–12) petals and stamens, a feature shared with an as-yet undescribed species of Polyscias from the Col de Maningotry in extreme southeastern Madagascar. By contrast, most other members of the genus in Madagascar have a 5-carpellate gynoecium and 5 stamens, although a few have just 2, 3 or 4 carpels, styles, and stamens. Polyscias bernardiana can easily be distinguished from P. duplicata by the evident articulation on its pedicel at the point of insertion of the ovary, a feature found in all other species in Madagascar with the exception of P. duplicata , which has unarticulated pedicels and was therefore long placed in the segregate genus Gastonia , including by BERNARDI (1971, 1980b). Our new species also has strictly pinnately compound leaves whereas P. duplicata often has a somewhat smaller auxiliary leaflet borne in the axil of most of its main leaflets, such that 4 (rather than 2) leaflets are thus inserted at most nodes along the rachis, a feature reflected in the specific epithet.

While the geographic range of Polyscias bernardiana is rather restricted, it is often quite abundant in the areas where it grows and generally stands out due to its distinctive habit. It is thus surprising that only three fragmentary gatherings were made until the late 20TH century even though P. bernardiana occurs at Andasibe (Perinet), one of the most easily accessible and frequently visited collecting sites in the country. BERNARDI (1971, 1980b) associated one of these collections as well as several others with P. repanda (DC.) Baker , a species endemic to Réunion Island that only vaguely resembles P. bernardiana ( MARAIS, 1984, 1990), although given the poor quality of the Malagasy material available to him, this error is perhaps understandable and is in any case one of the very few details of Indian Ocean Araliaceae that Bernardi did not get right.

Paratypi. – MADAGASCAR. Reg. Alaotra-Mangoro [Prov. Toamasina]: Moramanga, Ambatovy , 18°49'S 48°18'E, 3–5.II.2004, y.fr., Andriatsiferana 2504 ( MO [2 sheets], P, TAN) ; ibid. loco, 18°49'45"S 48°18'59"E, 1240 m, 20.XII.2004, bud, Antilahimena 3075 ( MO [3 sheets], P [2 sheets], TAN) ; ibid. loco, 18°49'19"S 48°20'08"E, 1094 m, 3.II.2005, y.fr., Antilahimena 3291 ( MO, TAN) ; ibid. loco, 18°50'10"S 48°19'32"E, 1093 m, 11.II.2005, y.fr., Antilahimena 3371 ( MO [2 sheets], P [2 sheets], TAN) ; ibid. loco, 18°49'38"S 48°18'48"E, 1250 m, III.2005, y.fr., Antilahimena 3727 ( MO [2 sheets], P [2 sheets], TAN) ; ibid. loco, 18°50'14"S 48°18'39"E, 1154 m, 19.I.2007, fl., Antilahimena 5151 ( MO [2 sheets], P [2 sheets], TAN) ; ibid. loco, 18°50'18"S 48°18'36"E, 1167 m, 12.III.2007, y.fr., Antilahimena 5479 ( MO [2 sheets], P [2 sheets], TAN) ; ibid. loco, 18°50'12"S 48°19'57"E, 1177 m, 23.V.2008, fr., Antilahimena 6213 ( MO) ; ibid. loco, 18°50'10"S 48°19'10"E, 1141 m, 2.IV.2010, ster., Antilahimena 7448 ( MO, TAN) ; Lakato, Ambodigavo, forêt d’Andranotelo à 2 km W du village d’Ambodigavo , 19°03'11"S 48°21'34"E, 1063 m, 22.XII.2004, y.fr., Lehavana 237 ( MO, P [3 sheets], TAN) ; ibid. loco, fl., Lehavana 238 ( MO [2 sheets], P [3 sheets], TAN) ; along road to Lakato , c. 15 km S of RT 2, 1100 m, 17.X.2004, bud, Lowry 6539 ( MO [4 sheets]) ; forêt d’Analamazaotra , [18°56'S 48°26'E], 800 m, s.d., bud, Perrier de la Bâthie 6840 ( P [4 sheets]) ; Andasibe (Perinet), forest NE of graphite mine, [18°53'S 48°28'E], 1000 m, 23.VII.1987, fr., Phillipson 2136 ( MO [4 sheets], P [2 sheets]) ; Ambatovy Mining Site , c. 13 km NE of Moramanga , Ankitrokely forest , along road to Analamay conservation zone, 18°49'51"S 48°18'50"E, 1194 m, 16.XII.2009, bud, Plunkett 2408 ( MO, NY, P, TAN) ; Phelps Dodge project site , c. 15 airkm NE of Moramanga, c. 11 km E of Antanambao, Ambatovy , 18°51'07"S 48°18'47"E, 1100 m, 30.I.1997, bud, Rakotomalaza 1050 ( MO [2 sheets], P, TEF) ; between Ambatovy-South and Analamay-East, Torotorofotsy River , Berano , 18°50'S 48°19'E, 1100 m, 20.II.1997, fr., Rakotomalaza 1141 ( MO, P, TAN) ; ibid. loco, 18°50'01"S 48°18'47"E, 1180 m, 14.V.1997, fr., Rakotomalaza et al. 1314 ( MO [2 sheets]) ; Vavantenina, Savaharina, Zahamena PN, à côté de la rivière Ihofika , 17°41'08"S 48°59'43"E, 650 m, 14.VI.2001, fl., Rakotonandrasana 496 ( MO, P, TAN) ; Cne Manakambahiny Est, Andranohofa, à 15 km au NE d’Androrangabe , piste vers Ambodivoahangy , [17°41'S 48°49'E], 800–900 m, 24.VII.2003, y.fr., Rakotonandrasana 712 ( MO, P, TAN) ; Ambatovy , zone de conservation, 18°50'40"S 48°18'33"E, 1126 m, 22.VI.2008, ster., Rakotonandrasana 1362 ( MO) ; ibid. loco, 18°50'40"S 48°18'34"E, 1106 m, 26.IX.2008, bud, Rakotondrajaona 577 ( MO, TAN) ; Cne Ambalabe, Fkt. Ambinanindrano II, Ambinanin’ny Ampotamena stream, 19°09'01"S 48°34'55"E, 6.X. 2009, 604 m, bud, A. Randrianasolo 1109 ( MO [2 sheets], P) ; Moramanga, Andasibe, corridor forestier Analamay Mantadia , 18°47'15"S 48°24'43"E, 996 m, 24.IV.2012, y.fr., Rasoazanany 95 ( MO, P [2 sheets], TAN) ; Analamazaotra-Périnet PN, Barika-Amboasary , limite SE, 18°56'55"S 48°26'18"E, 1081 m, 13.III.2013, y.fr., Rasoazanany et al. 480 ( MO [3 sheets], P [3 sheets], TAN) ; Ambatovy , 18°52'08"S 48°20'34"E, 1019 m, 21.I.2010, Razafimelison 3 ( MO [2 sheets], TAN) ; ibid. loco, 18°49'20"S 48°20'07"E, 1071 m, 2005, fl., Razafindraibe & Antilahimena 65 ( MO [2 sheets], P [2 sheets], TAN) ; Cne Ambohibary, Fkt. Menalamba, forêt Ampangadiatrandraka , 18°51'52"S 47°59'05"E, 1063 m, 7.XII.2006, y.fr., J. Razanatsoa 231 ( MO [2 sheets], P [2 sheets], TAN) ; Analamazaotra, Andasibe RS, [18°56'S 48°26'E], 23.III.1949, fr., Service Forestier 572 ( P [3 sheets]) ; ibid. loco, 23.III.1949, fr., Service Forestier 577 ( P [3 sheets]) ; Perinet , [18°56'S 48°26'E], 31.III.1954, y.fr., Service Forestier 10342 ( P [3 sheets]) ; Berano village to the crossroad to Ambatovy , 18°50'16"S 48°19'19"E, 965 m, 11.IV.2007, fr., Wen 9690 ( MO [4 sheets], US) . Reg. Atsinanana [Prov. Toamasina]: Brickaville, Ambodilendemy, vers le sommet d’Ankerana , 18°25'37"S 48°47'02"E, 842 m, 20.III.2011, fr., Ravelonarivo 3732 ( MO [3 sheets], P [3 sheets], TAN) ; Vatomandry, Vodiriana village au NW du Toby Lemazava, 19°09'48"S 48°32'14"E, 758 m, 11.II.2007, fl., Razanatsima 212 ( MO, P [2 sheets], TAN).

Figures

Fig. 1. – Polyscias bernardiana Lowry & Callm. A. Inflorescence held by the first author; B. Immature infructescence; C. Detail of a flower; D. Branch with terminal leaves; E. Detail of an umbellule with mature fruits. [A: Lowry et al. 7065; B–C: Rasoazanany 480; D–E: A. Randrianasolo 1109] [Photos: A–C:P. Antilahimena; D–E:A. Randrianasolo]

Fig. 2. – Polyscias bernardiana Lowry & Callm. A. Inflorescence; B. Leaflet; C. Detail of leaf petioles; D. Branch with terminal leaves; E. Detail of an umbellule with mature fruits; F. Portion of an immature infructescence. [A: Lowry et al. 7065, TAN; B, D: A. Randrianasolo 1109, TAN; C: Rasoazanany 380, TAN; E: Antilahimena 6218, TAN; F: Rasoazanany 480, TAN] [Drawing: R.L. Andriamiarisoa]

Fig. 3. – Luciano Bernardi photographing the corky bark of a fire-resistant tree in the campo cerrado of Canindeyú Department (NE Paraguay) during a 1980 expedition conducted for the Coopération Technique Suisse. [Photo: R. Spichiger]