Abrahamia ibityensis (H. Perrier) Randrian. & Lowry

Randrianasolo, Armand, Lowry II, Porter P. & Schatz, George E., 2017, Taxonomic treatment of Abrahamia Randrian. & Lowry, a new genus of Anacardiaceae from Madagascar, Boissiera 71, pp. 1-152 : 74-75

13. Abrahamia ibityensis (H. Perrier) Randrian. & Lowry , comb. nova ( Fig. 11C ).

≡ Protorhus ibityensis H. Perrier in Mém. Mus. Natl. Hist. Nat. 18: 263. 1944.

Lectotypus (designated here): Madagascar. Prov. Antananarivo: Mont Ibity , quartzites, [20°07’S 47°01’E], c. 2000 m, IX.1921, fl., Perrier de la Bâthie 13976 ( P [ P00722649 ]!; isolecto-: P [ P00722650 , P00722651 ]!) . Syntypi: MADAGASCAR. Prov. Antananarivo: Ibity , [20°07’S 47°01’E], 1900-2000 m, s.d., ster., Perrier de la Bâthie 5840 ( P [ P06169079 ]!) ; ibid. loco, c. 2000 m, III.1921, fr., Perrier de la Bâthie 13571 ( P [ P00722653 , P00722654 ]!) ; ibid. loco, Perrier de la Bâthie 13571bis ( P [ P00722652 ]!) . Sine loco: s.d., Decary 13085 “ A ” ( P [ P06169081 ]!) .

Description

Shrubs 0.25-2 m tall, bark with white or translucid latex; young twigs glabrescent, with lenticels, waxy. Leaves alternate or subopposite; blades oblong to elliptic, 3-7 3 1.2-3 cm, subcoriaceous, apex retuse or emarginate, margin entire and slightly revolute, base cuneate to obtuse, adaxial surface glabrous, sometimes glossy, abaxial surface with scattered, appressed indument, more so along the midvein, venation craspedodromous, midvein prominent abaxially, secondary veins 15-30 pairs, visible, parallel, 0.5-2 mm apart, very slightly raised on both surface, tertiary veins impressed and very rarely visible on both surfaces; petiole 5-7 mm long, shallowly canaliculate on adaxial surface, pubescent when young, glabrescent. Inflorescence axillary or terminal, a thyrse, 1.5-3 cm long, pubescent. Male and female flowers 5-merous; pedicel c. 0.3-0.5 mm long, pubescent; calyx lobes ovate to deltate, 1.5-1.8 3 1.5-2 mm, imbricate, glabrous on both surfaces, margin sparesly ciliate; corolla lobes ovate, 2.5-3 3 1.5-2 mm, imbricate, glabrous, white; stamens 5. Male flowers with filaments 1-1.3 mm long, glabrous on both surfaces, white, anthers c. 1 mm long, ovoid or obloid, sterile, yellow, glabrous; disk dish-shaped, c. 2 mm in diam., glabrous; ovary rudimentary. Female flowers with filaments 1-1.5 mm long, glabrous, white, anthers 0.5 mm long, ovoid, yellow, glabrous; disk c. 1.5-2 mm in diam., glabrous; ovary very widely ovoid, 1 3 1 mm, glabrous, placentation parietal; style apical, shortly trifid, 0.5 mm long, glabrous, stigmas capitate. Fruits 1.5-1.8 3 1.5 cm, widely depressed-ovate, glabrous, with longitudinal striations, pyrenes with a few peripheral resiniferous canals, cotyledons separable.

Distribution, ecology and phenology

Abrahamia ibityensis is only known from Mt. Ibity and its surroundings, to the SW of the town of Antsirabe ( Map 2 ), at elevations between 1500 and 2000 m, where it grows mostly on rocky soil in areas that are frequently subjected to fire. Flowers have been recorded in September and October, and fruiting material has been collected in February and March.

Conservation status

With an EOO of 34 km 2, a minimum AOO of 28 km 2, and 9 known localities representing 7 locations, most of which are situated within a newly established protected area (Ibity) but are still subjected to fire and possible degradation leading to a projected decline in all quality of habitat, A. ibityensis is assigned a provisional conservation status of “Vulnerable’’ [VU B1ab(iii)+2ab(iii)] using the IUCN Red List Categories and Criteria ( IUCN, 2012).

Notes

Abrahamia ibityensis can be distinguished from all of its congeners by its oblong to elliptic leaves with inconspicuous tertiary venation and the presence of a few peripheral resiniferous canals in the seeds, which results in the two cotyledons being distinct and easily separable.

Among the syntypes of Protorhus ibityensis , we have selected Perrier de la Bâthie 13976 as the lectotype because it, along with the two isolectotypes, comprise more complete specimens than the other collections cited in the protologue (Decary 13085 “A”, Perrier de la Bâthie 5840, 13571, and 13571bis [incorrectly cited in the protologue as 1357bis]). We have added the letter “A” to the Decary specimen because this same number has been applied to a specimen of Beilschmiedia microphylla (Kosterm.) Kosterm. (Lauraceae) that bears an original label, whereas the label accompanying the syntype of Protorhus ibityensis was clearly prepared by someone else.

Additional material examined

Madagascar. Prov. Antananarivo: Antsirabe, Ibity ( S) , W of Ambohimanjaka , [20°15’S 47°03’E], 2000 m, 22.XII.1985, y. fr., Dorr & Rakotozafy 4528 ( MO, NY, P, TAN) ; Ibity , 13.X.1970, fl., Keraudren-Aymonin & Aymonin 24565 ( P) ; Ibity, Ambero, S end of Amboropotsy , 20°10’17’’S 47°02’07’’E, 1700-1800 m, 23.II.2003, fr. & fl., Koopman 170 ( MO, P, TAN) ; Ibity , 27 km S of Antsirabe, 20°05’S 47°10’E, 1500-2240 m, 13.X.1993, fl., Lewis et al. 741 ( G, K, MO, NY, P, TAN) ; Ibity , 23 km E de la cimenterie, 20°04’40’’S 47°00’10’’E, 1830 m, 3.X.1996, fl., Randrianaivo et al. 6 ( MO, P, TAN) ; ibid. loco, Randrianaivo et al. 9 ( MO, P, TAN) ; Ibity , E of Alatsinainy Ibity village and the cement factory, 20°06’S 46°59’E, 1600 m, 2.X.1996, fl., A. Randrianasolo 485 ( G, K, MO, P, TAN) ; ibid. loco, A. Randrianasolo 486 ( MO, P, TAN) ; Ibity, Falirano , 20°04’24’’S 47°00’10’’E, 1470 m, 20. I.2003, fr., Rogers et al. 82 ( G, MO, P, TAN) ; abords du sommet de l’Analabe, dans la chaine d’Ampandrianombilapa , S de l’Ibity, [20°05’43’’S 47°00’14’’E], 1900 m, 19.XI.1967, fr., Service Forestier 27394 ( P, TEF) . Prov. Fianarantsoa: Ambatofinanadrahana, Itremo , E. du Mt. Ambatoandrano , 20°05’25’’S 47°00’07’’E, 1693 m, 1.XI.2001, fl., Andriamihajarivo 49 ( MO, P, TAN) .

Figures

Map 2. Geographic distribution of species of Abrahamia Randrian. & Lowry

Fig. 11. Abrahamia humbertii (H. Perrier) Randrian. & Lowry (A-B) and A. ibityensis (H. Perrier) Randrian. & Lowry (C). A. DetaiL of Leaf base Lower surface venation and fruits [Ratovoson 1154]; B. Fruits, from side [Ratovoson 1154]; C. Fruits, from side [Andriambololonera 314].