Abrahamia pauciflora (Engl.) 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 : 111-112

26. Abrahamia pauciflora (Engl.) Randrian. & Lowry , comb. nova.

≡ Protorhus pauciflora Engl. in A. DC. & C. DC., Monogr. Phan. 4: 313. 1883.

Lectotypus (designated here): MADAGASCAR. Prov. Antsiranana: Rég. Diana , Nossibe, I.1850, fl. & y. fr., Boivin 2257 ( P [ P00580352 ]!; isolecto-: G!, P [ P00364873 , P06774888 , P06774892 ]!, MO- 6684876 !, TAN!).

Description

Trees 6-11 m tall, 11-15 cm DBH; young branch tips covered with short and appressed indument. Leaves opposite or subopposite; blade obovate, 3.9-9.2 3 1.8-4 cm, chartaceous, apex rounded to emarginate, margin undulate, base cuneate to attenuate, adaxial surface glabrous, abaxial surface with scattered short appressed indument, venation craspedodromous, midvein prominent abaxially, secondary veins 14-17 pairs, more or less parallel and ascending, 3-9 mm apart, widely spaced at leaf mid-section, raised on both surfaces or some impressed near margin, tertiary veins impressed, not very visible, especially on adaxial surface; petiole 8-15 mm, c. 1 mm in diam., canaliculate on adaxial surface, covered with short, appressed indument when young, glabrescent. Inflorescence always axillary, a panicle, very short, up to 1.5 cm long, with no more than 5 flowers, axes strigose. Male flowers unknown. Female flowers 5-merous, small, c. 1 mm long, subtended by a triangular bract with indument; pedicel 1 mm long; calyx lobes depressed ovate, very small, 0.5 3 1 mm, glabrous on both surfaces; corolla lobes ovate, thick, c. 2 x 1 mm, glabrous on both surfaces; staminodes with filaments c. 0.8 mm long, glabrous, anthers c. 0.3 mm long, ovoid, sterile, glabrous; disk cupuliform, glabrous, c. 1.5 mm in diam.; ovary spherical glabrous, style short, thick, 0.5 mm long. Fruits unknown.

Distribution, ecology and phenology

Abrahamia pauciflora is restricted to NW Madagascar, where it has been collected on the island of Nosy Be and in the Ambongo-Boina area ( Map 6 ) in humid forest. Material with floral buds and flowers has been collected in November and January (the fruiting period is not known).

Conservation status

With a minimum AOO of 4 km 2 and a single known extant subpopulation, which is within a protected area (Ampasindava), and considering that the historical locality at Maevarano was documented in 1908, well more than 3 generations ago, A. pauciflora is assigned a preliminary conservation status of “Least Concern’’ [LC] using the IUCN Red List Categories and Criteria ( IUCN, 2012).

Notes

Abrahamia pauciflora can easily be distinguished from other members of the genus by the combination of its leaves with an attenuate base and very widely spaced secondary veins (to 9 mm apart in the median section of the blade), and very short inflorescence (not exceeding 1.5 cm long) usually bearing only 1-5 flowers.

Contrary to what is indicated in many online databases, the name Protorhus pauciflora (≡ Abrahamia pauciflora ) was not treated in ENGLER (1881: 421 or 422), but rather was published two years later by the same author in his treatment of Anacardiaceae for the Monographiae Phanerogamarum ( ENGLER, 1883: 313). Curiously, ENGLER (1883) erroneously cited that name as having been published in his earlier work ( ENGLER, 1881: 421).

While one of the specimens of Boivin 2257 in the Paris herbarium has the handwritten word ‘type’ on the label, this was probably added subsequent to the publication of Protorhus pauciflora . We have chosen to designate this specimen as the lectotype because it bears Boivin’s original label. Two additional specimens of Boivin 2257 have labels indicating that they came from Mayotte in the Comoro Islands, but as indicated subsequently by Perrier de la Bâthie (in herb.), they are without question part of the same gathering as the material from Nossi Be.

Additional material examined

MADAGASCAR. Prov. Antsiranana: Ampasindava, forêt d’Andranomatavy , 13°40’40’’S 47°58’35’’E, 215 m, 2.XII.2009, bud, Ammann et al. 467 ( G, MO, P, TEF) ; ibid. loco, 13°40’04’’S 47°59’21’’E, 295 m, 25.XI.2009, fl., Madiomanana et al. 272 ( G, MO, P, TEF) . Prov. Mahajanga: Morarivo, Maevarano , près de Majunga, [15°56’S 46°31’E], VII.1908, ster., Perrier de la Bâthie 2341 ( P).

Figures

Map 6. Geographic distribution of species of Abrahamia Randrian.& Lowry