Beguea Capuron, Beguea ankeranensis G.E. Schatz & Lowry,

George E. Schatz, Roy E. Gereau & Porter P. Lowry Ii, 2017, A revision of the endemic Malagasy genus Beguea (Sapindaceae), Candollea 72, pp. 45-65: 46-47

publication ID

http://doi.org/ 10.15553/c2017v721a6

persistent identifier

http://treatment.plazi.org/id/BF6C6E20-FF89-FF9C-FCC9-125F2253FAE4

treatment provided by

Plazi

scientific name

Beguea Capuron Beguea ankeranensis G.E. Schatz & Lowry
status

 

Beguea Capuron 

in Mém. Mus. Natl. Hist. Nat., B, Bot. 19: 105. 1969.

Typus: Beguea apetala Capuron. 

Dioecious small to large trees with simple or rarely stellatefasciculate indument. Leaves alternate, trifoliolate or paripinnately compound with 4-30 alternate to subopposite, entire leaflets, the rachis usually extending slightly beyond the terminal leaflet giving the impression of an aborted leaflet; pseudostipules absent. Inflorescences axillary, sometimes borne on stems below the leaves (ramiflorous), long racemose. Flowers actinomorphic; calyx united basally, (5-)6-7(-8)-lobed; petals absent; disc cushion-shaped, the margin sinuate; stamens 6-8(-10), filaments long, slender, anthers ovate to oblong, laterally dehiscent; staminodia in female flowers resembling short stamens; ovary 3-locular, style longer than the ovary, dividing apically into 3 distinct stigmas, ovule 1 per locule; pistillode in male flowers minute. Fruit indehiscent, globose to obovoid, 1-seeded, dry to somewhat fleshy or woody, crowned by the apiculate remnant of the style; seed surrounded by a translucent, fleshy arillode, the hilar scar basal, the cotyledons highly ruminate.

Notes. – A genus of ten species, occurring in humid and subhumid forest, rarely in dry forest. The genus name honors the French botanist Louis H. Bégué, who founded the Service Forestier collection series in Madagascar.

Key to the species of Beguea 

1. Apex of leaflets retuse to deeply emarginate; fruit with mesocarp 3-4.7 mm thick; Andohahela PN......... 3. B. australis 

1a. Apex of leaflets rounded to acute or acuminate; fruit with mesocarp (when known) less than 2 mm thick ............. 2

2. Petiole and leaf rachis covered with tufts of very short golden stellate-fasciculate trichomes............................. 3

2a. Petiole and leaf rachis glabrous or with persistent indument of simple trichomes.............................................. 4

3. Apex of leaflets acute to acuminate and short-mucronate, the lamina densely punctate above, the margin slightly revolute; inflorescences unbranched........ 7. B. galokensis 

3a. Apex of leaflets rounded, not mucronate, the lamina not punctate above, the margin strongly revolute; inflorescences sometimes branched.............. 4. B. betamponensis 

4. Petiole and leaf rachis with dense persistent indument ... 5

4a. Petiole and leaf rachis glabrous or initially with sparse indument, then glabrescent ........................................... 9

5. Leaflets conduplicate, usually folded along the midvein in pressed material............................................................. 6

5a. Leaflets flat in pressed material..................................... 7

6. Leaflets 3-14, the base markedly asymmetrical, the margins usually strongly revolute, secondary veins 8-15 per side; widespread, Manakara S to Farafangana...... 2. B. apetala 

6a. Leaflets 4-6, the base symmetrical, the margins flat and minutely thickened but not revolute, secondary veins 7-10 per side; Montagne des Français................. 6. B. borealis 

7. Leaflets 6-8, the apex distinctly acuminate, the acumen acute; pedicels c. 1 mm long; anthers 2.2-2.5 mm long; Ankerana............................................. 1. B. ankeranensis 

7a. Leaflets 7-16, the apex acute or acuminate, the acumen rounded to irregularly or slightly retuse; pedicels 2.5-4 mm long; anthers c. 1 mm long .......................................... 8

8. Leaflets with secondary veins emerging at a 45 ̊ angle  to the midvein; inflorescence densely light reddish chocolate tomentose; pedicels slender, 0.2-0.5 mm in diam. in flower, sparsely light chocolate tomentulose, 0.9-1 mm in diam. in fruit, glabrous; sepals c. 0.5 mm long; fruit 1.7-1.8 cm long, c. 1.2 cm in diam., ellipsoid to obovoid; Lokobe PA ............................................................ 5. B. birkinshawii 

8a. Leaflets with secondary veins emerging at a 25 ̊ angle  to the midvein; inflorescence densely ferruginous tomentose; pedicels stout, 0.7-0.9 mm in diam. in flower, densely ferruginous tomentose, 1.3-1.5 mm in diam. in fruit; sepals c. 1.5 mm long; fruit 2.3-2.8 cm in diam., spheroid; Andohahela, Ranomafana and “Corridor forestier Marojejy- Anjanaharibe Sud-Tsaratanana Nord” .............. 9. B. turkii 

9. Leaflets with a flat margin; calyx glabrous; Tsaratanana PA ................................................... 8. B. tsaratananensis 

9a. Leaflets with a revolute margin; calyx sparsely puberulous outside; widespread, Marojejy PA S to Bemangidy (N of Tolagnaro)................................................ 10. B. vulgaris 1. Beguea ankeranensis G.E. Schatz & Lowry  , spec. nova

( Fig. 1View Fig. 1, 2View Fig. 2 A).

Typus: MADAGASCAR. Prov. Toamasina: Atsinanana Region, Brickaville, Anjahamamay, Anivoranokely, Ankerana forest , 18̊24’21’’S 48̊48’18’’E, 700 m, 19.I.2012, fl., Antilahimena 7978 (holo-: MO-6704230!;GoogleMaps  iso-: G [G00341688]!, K!, P [P00580357]! TAN).

Haec species a congeneris foliorum petiolo rhachideque indumento aureobrunneo tomentulosis, foliolis 6 ad 8 in sicco complanatis apice acute acuminatis, pedicellis c. 1 mm longis atque antheris 2.2-2.5 mm longis distinguitur.

Tree c. 15 m tall; stems densely golden brown tomentulose. Petioles 2.6-4 cm, densely golden brown tomentulose. Leaves with 6-8 subopposite to alternate leaflets; rachis 3.8-7 cm, keeled above, golden brown tomentulose; petiolule 2.5-3 mm, golden brown tomentulose; leaflet blade 2.8-7 × 1.2-2.2 cm, elliptic, papyraceous to subcoriaceous, flat in pressed material, glabrous and only slightly glossy above, sparsely light brown tomentulose on midvein and secondary veins below, base weakly to markedly asymmetrical, acute to nearly decurrent, margins minutely thickened, not revolute, apex distinctly acuminate, the acumen acute, midvein distinctly raised and knife-like above and below, secondary veins (8-)10-13 per side, flat to slightly impressed above, raised below, tertiary venation obscure above, slightly raised and evident below. Inflorescence axis 16-19 cm long, c. 1 mm in diam., unbranched, dark chocolate brown, densely golden brown tomentulose; bracts c. 1 mm, narrowly triangular, adaxially concave; pedicels c. 1 mm, c. 0.8 mm in diam., densely golden brown tomentulose. Male flowers with a shallowly cupulate, (4-)5-lobed calyx, the lobes broadly triangular, c. 1 × 1.2 mm, acute, densely golden brown tomentulose outside, densely golden setaceous inside; stamens 8, filaments 1-3 mm, glabrous, anthers 2.2-2.5 × c. 0.8 mm, ellipsoid; disc and pistillode densely golden setaceous, the trichomes to 0.5 mm. Female flowers not seen. Fruit not seen.

Conservation status. – Known only from a single collection from well within an intact forest block of the newly designated Corridor Ankeniheny Zahamena PA ( Fig. 3View Fig. 3), and lacking any additional information on population size, B. ankeranensis  is assigned a provisional status of “Least Concern” [LC] using the IUCN Red List Criteria ( IUCN, 2012), with the caution that this status is highly dependent on continued effective protection.

Notes. – Beguea ankeranensis  is known only from the type collection in humid forest at Ankerana ( Fig. 3View Fig. 3), which is included within the recently decreed Corridor Ankeniheny Zahamena PA. It can be easily distinguished from the two species most similar morphologically ( B. birkinshawii  and B. turkii  ) by its leaflets with a long-acuminate apex and an acute acumen (vs acute to short acuminate apex and rounded to retuse acumen), short pedicels c. 1 mm long (vs 2.5-4 mm long), and large anthers 2.2-2.5 mm long (vs only 1 mm long) ( Fig. 1View Fig. 1, 2View Fig. 2 A).

1. Beguea ankeranensis G.E. Schatz & Lowry  , spec. nova

( Fig. 1View Fig. 1, 2View Fig. 2 A).

Typus: MADAGASCAR. Prov. Toamasina: Atsinanana Region, Brickaville, Anjahamamay, Anivoranokely, Ankerana forest , 18̊24’21’’S 48̊48’18’’E, 700 m, 19.I.2012, fl., Antilahimena 7978 (holo-: MO-6704230!;GoogleMaps  iso-: G [G00341688]!, K!, P [P00580357]! TAN).

Haec species a congeneris foliorum petiolo rhachideque indumento aureobrunneo tomentulosis, foliolis 6 ad 8 in sicco complanatis apice acute acuminatis, pedicellis c. 1 mm longis atque antheris 2.2-2.5 mm longis distinguitur.

Tree c. 15 m tall; stems densely golden brown tomentulose. Petioles 2.6-4 cm, densely golden brown tomentulose. Leaves with 6-8 subopposite to alternate leaflets; rachis 3.8-7 cm, keeled above, golden brown tomentulose; petiolule 2.5-3 mm, golden brown tomentulose; leaflet blade 2.8-7 × 1.2-2.2 cm, elliptic, papyraceous to subcoriaceous, flat in pressed material, glabrous and only slightly glossy above, sparsely light brown tomentulose on midvein and secondary veins below, base weakly to markedly asymmetrical, acute to nearly decurrent, margins minutely thickened, not revolute, apex distinctly acuminate, the acumen acute, midvein distinctly raised and knife-like above and below, secondary veins (8-)10-13 per side, flat to slightly impressed above, raised below, tertiary venation obscure above, slightly raised and evident below. Inflorescence axis 16-19 cm long, c. 1 mm in diam., unbranched, dark chocolate brown, densely golden brown tomentulose; bracts c. 1 mm, narrowly triangular, adaxially concave; pedicels c. 1 mm, c. 0.8 mm in diam., densely golden brown tomentulose. Male flowers with a shallowly cupulate, (4-)5-lobed calyx, the lobes broadly triangular, c. 1 × 1.2 mm, acute, densely golden brown tomentulose outside, densely golden setaceous inside; stamens 8, filaments 1-3 mm, glabrous, anthers 2.2-2.5 × c. 0.8 mm, ellipsoid; disc and pistillode densely golden setaceous, the trichomes to 0.5 mm. Female flowers not seen. Fruit not seen.

Conservation status. – Known only from a single collection from well within an intact forest block of the newly designated Corridor Ankeniheny Zahamena PA ( Fig. 3View Fig. 3), and lacking any additional information on population size, B. ankeranensis  is assigned a provisional status of “Least Concern” [LC] using the IUCN Red List Criteria ( IUCN, 2012), with the caution that this status is highly dependent on continued effective protection.

Notes. – Beguea ankeranensis  is known only from the type collection in humid forest at Ankerana ( Fig. 3View Fig. 3), which is included within the recently decreed Corridor Ankeniheny Zahamena PA. It can be easily distinguished from the two species most similar morphologically ( B. birkinshawii  and B. turkii  ) by its leaflets with a long-acuminate apex and an acute acumen (vs acute to short acuminate apex and rounded to retuse acumen), short pedicels c. 1 mm long (vs 2.5-4 mm long), and large anthers 2.2-2.5 mm long (vs only 1 mm long) ( Fig. 1View Fig. 1, 2View Fig. 2 A).

Kingdom

Plantae

Phylum

Tracheophyta

Class

Magnoliopsida

Order

Sapindales

Family

Sapindaceae

Kingdom

Plantae

Phylum

Tracheophyta

Class

Magnoliopsida

Order

Sapindales

Family

Sapindaceae

Genus

Beguea