Introduction

In Madagascar six genera belong to tribe Gardenieae DC. (Rubiaceae): the characters and distributions of each genus are given in Davis & Rakotonasolo (2003). In Madagascar the Gardenieae is represented by the following genera: Gardenia Ellis (Rakotonirina et al. 2012), Melanoxerus Kainul. & B.Bremer (formerly Euclinia Salisb.; Kainulainen & Bremer 2014), Catunaregam Wolf, Mantalania Capuron ex J.-F.Leroy, Pseudomantalania J.-F.Leroy (Leroy 1974) and Hyperacanthus E.Mey. ex Bridson. Hyperacanthus (Rakotonasolo & Davis 2001) currently comprises 11 species, nine in Madagascar (Rakotonasolo & Davis 2001, 2002, 2004, 2006) and two in Africa (Bridson & Robbrecht 1985), although in Madagascar around 40 species still require scientific description (Rakotonasolo 2007). Based on the work of Rakotonasolo & Davis (2001, 2002, 2004, 2006) the salient characteristics of the genus Hyperacanthus are: evergreen leaves, stipules caducous, tightly rolled and often slightly twisted; leaves lacking domatia (except H. perrieri); inflorescences terminal but often appearing axillary (overtopped) due to shoot extension; paired bracteoles at the base of the calyx and fruit; corolla lobes overlapping to the right in bud; ovary 2- or 4-locular with axile placentation (some 4-locular ovaries with incomplete septa at the base [i.e. parietal], which become 4-locular above the basal part [transitional parietal-axile placentation]); in general the placentation patterns are complicated (Rakotonasolo & Davis 2006); anthers more or less sessile or with very short filaments (c. 0.1 mm long); and calyx persistent and obvious in fruit.

Most (c. 90%) of Hyperacanthus species grow in humid or sub-humid, evergreen forest, and have evergreen leaves. There are, however, representatives of the genus that occur in the seasonally dry, deciduous forests, in western and south-western Madagascar, and, unlike other Hyperacanthus, have deciduous leaves. These species have sometimes been informally known as ‘sofikomba’ or the ‘sofikomba alliance’ due to the fact that many of them have leaves shaped like a lemur’s ear. The translation of the Malagasy sofikomba to English is ‘lemur’s ear’ (sofi = ear and komba = lemur). Lemurs also eat the fruits of ‘sofikomba’. The vernacular name variant Sofiankomba is also used for these plants, as are other Malagasy vernacular names. These ‘sofikomba’ species differ from other Hyperacanthus, due to their deciduous leaves (vs persistent, evergreen), their characteristic ovate to orbicular or reniform leaf shape (vs elliptic to oblanceolate), thin (chartaceous to chartaceous-subcoriaceous) leaf blades (vs thick [coriaceous or subcoriaceous]) and absence of bracteoles subtending flowers and fruits (vs present). Historically, it has been difficult to determine the generic placement of species belonging to the sofikomba alliance, due to their unique morphology and general appearance.

In this study, based on morphological data, we confirm that these species belong to the genus Hyperacanthus and constitute a discrete grouping of species, in support of available molecular data, which shows that the sofikomba alliance is monophyletic but nested within Hyperacanthus (Rakotonasolo 2007). To encompass the species level variation within the sofikomba alliance, we describe four new species. We also provide a descriptive overview of morphology, (including pollen), a taxonomic account of the four species, including a key to the species, distribution maps, associated information, and provisional conservation assessments.

Materials and Methods

This revision is based on the examination of herbarium specimens, field observation of living plants and their habitats, and palynological study. Herbarium specimens were examined from six herbaria: BR, CAS, K, P, TAN and TEF (abbreviations after Holmgren et al. 1990; Thiers 2020, continuously updated). All specimen duplicates cited have been seen by the first author. Pollen grains from herbarium material were acetolysed according to the ‘wetting agent’ method (Reitsma 1969). Using a scanning electron microscope (SEM), external features were observed on grains that had been suspended in 70% ethanol and left to dry. Glycerine jelly slides were observed under a light microscope. Polar axis length (P) and equatorial diameter (E) were measured using the software programme Carnoy (Schols et al. 2002). Pollen terminology follows Punt et al. (2007). Species distribution maps were made with the software programme iMap (Schols et al. 2001). Georeferenced specimen data were imported into GeoCAT (Bachman et al. 2011) to calculate area of occupancy (AOO) and extent of occurrence (EOO) for each species. AOO and EOO results were combined with field observations to produce conservation assessments based on the IUCN Red List Categories and Criteria (IUCN 2012).

Results

Habit and vegetative morphology

Species of the sofikomba alliance (‘sofikomba’) are small to medium-sized trees, up to 16 m high, or sometimes shrubs, with a horizontal to oblique branching pattern (Fig. 1A, D, J). The bark is smooth with caducous plates, in mottled shades of light to dark grey, becoming dark brown when old. Reduced shoots (brachyblasts; Figs 1H, 2A, C) are produced during the dry season (slow growth period) and regular shoots during the wet season (fast growth period). The shoots (branchlets) are cylindrical in cross section, and pubescent to tomentose. The vegetative buds are deltoid to deltoid-ovoid, slightly woody (Fig. 2B), and covered by fine hairs and resin. The leaves are deciduous, simple, opposite, decussate, chartaceous to chartaceous-subcoriaceous, ovate to orbicular or reniform, similar in outline shape to the ear of lemur, and petiolate (Figs 1H, 2A – C). The young leaves are often pubescent (Fig. 1M), at least on the midrib, otherwise the leaves are glabrous. On the mature leaves the secondary veins are prominent, sometimes obscure, ascending at angle of 30 – 45°, eucamptodromous to cladodromous; the tertiary veins are indistinct, and (reticulate) reticulodromous. The interpetiolar stipule is triangular to deltate in outline shape, with acute apices, often pubescent on the outside faces, and with colleters on the inside face. Domatia are present or absent, depending on the species.

Fig. 1.
figure 1

A – C Hyperacanthus decaryi. A flowering tree; B flower (9-merous); C flower (6-merous). D – H H. sofikomba. D flowering tree; E flower buds; F flower (5-merous); G flower (6-merous); H fruit. J – N H. piliformis. J flowering tree; K flower (6-merous); L flower (7-merous); M young leaves; N fruit. photos: franck rakotonasolo.

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Fig. 2.
figure 2

Hyperacanthus sofikomba. A fruiting branch; B flowering shoot; C calyx and stipule detail; D flower bud; E flower dissection; F style; G stigma. From Davis et al. 2503. Scale bar: A 25 mm; B 7.5 mm; C 8 mm; D – F 12.5 mm; G 5 mm. drawn by lucy t. smith.

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Inflorescence and flowers

The inflorescences are one per shoot and terminal, single–flowered and sessile (Fig. 2A). Bracts and bracteoles are absent. The flowers are hermaphroditic, appearing before the young leaves, 5-merous to 8 (– 9)-merous, and shortly pedicellate to sessile (Fig. 2A, D). The calyx (hypanthium) is cylindrical ovoid, and glabrous or pubescent (depending on the species); the calyx tube is tubular to infundibular, with ovate to deltate lobes, each lobe is acute at the apex, glabrous to puberulous on the outside surface and green. The corolla tube is long, much longer than the corolla lobes, infundibular (Fig. 2E), glabrous or puberulous on both surfaces (depending on species), and white when mature; the corolla lobes overlap to the right in bud (Fig. 2D), are broadly elliptic to ovate or obovate, usually glabrous (puberulous in H. piliformis), and white when mature. The nectary disc is annular. The stamens are sessile to subsessile, the anther sacs linear (Fig. 2E), white, dorsifixed, introrse, longitudinally dehiscent, and are slightly exserted. The ovary is ovoid, and contains numerous ovules, embedded in a placenta matrix (Fig. 3A – C). As in some other genera of Madagascan Gardenieae, the number of locules varies from one species to another (Rakotonasolo & Davis 2006), and locule attachment changes, when moving from the base of the ovary to the top of the ovary (Rakotonasolo & Davis 2006). Thus, ascertaining the precise type of placentation in Hyperacanthus has been problematic (Hallé 1967; Robbrecht & Puff 1986; Sonké 1999; Rakotonasolo & Davis 2006). The main reason for this is because the number of the locules varies from the base to the apex of the ovary, depending on its position and length of attachment (Rakotonasolo & Davis 2006). Like many species of Hyperacanthus, in the sofikomba alliance the ovary is four-locular with axile placentation at the base and apex (Fig. 3B) but from the middle part towards both the apex and the base (Fig. 3C), the placentation becomes parietal. The style is cylindrical, glabrous, swollen in the upper part (+/- cylindrical to very narrowly conical, swollen part 4.3 – 6.6 mm long) and bifid at the apex (Fig. 2F); the stigmatic lobes are ovate to broadly ovate or elliptic to linear in outline (1 – 10 × 1 – 3.5 mm) (Fig. 2G), and slightly exserted to exserted (with respect to the throat of the corolla lobe).

Fig. 3.
figure 3

Hyperacanthus sofikomba. A LS of hypanthium, disc, and calyx, revealing ovules; B TS through mid-part of hypanthium, showing 4-locular placentation and ovules; C TS close to the base of hypanthium, showing incomplete 4-locular ovary; D fruit; E TS, middle part of fruit; F seeds, plan view (upper seed), side view (lower seed). From Davis et al. 2511. Scale bar: A 2 mm; B, C 1.5 mm; C 8 mm; D, E 2.5 mm; F 4 mm. drawn by lucy t. smith.

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Fruits and seeds

The fruit is ovoid to globose or obovoid (Fig. 3D), green for some time but purple when ripe (mature), as observed in the field. Sometimes the calyx lobes fall when the fruit matures. At maturity the locule walls degenerate and the fruit is either incompletely 4-locular or appears uni-locular with parietal placentation (Fig. 3E). The seeds are few to several per fruit and are embedded in the placenta matrix; each seed is more or less lenticular or angular-lenticular, white, with a more or less smooth (minutely and regularly rugulose) epidermis (Fig. 3F).

Pollen morphology

The pollen grains are released in monads, and are suboblate to oblate spheroidal, isopolar, with 4 – 5 (– 6) zonoporate apertures. Polar distance (P): (29 –) 31.6 – 34.5 (– 37) µm; Equatorial distance (E): (31 –) 34.5 – 37.9 (– 40) µm. The exine is reticulate, with walls sometimes interrupted on the endocolpium region. The diameter of the lumina is very large compared with the width of the muri. The pollen grains of the sofikomba alliance are of the same type as other members of Hyperacanthus, and are very similar to Hyperacanthus perrieri, i.e. with large lumina and interrupted walls on the endocolpium (Rakotonasolo 2007).

Ecology

Species of the sofikomba alliance are restricted to seasonally dry, deciduous forests of the northwestern, western, and southwestern parts of Madagascar, from the Daraina protected area in the north to the Andohahela nature reserve (réserve naturelle intégrale) in the south (Map 1). The species grow on sandy soil, lateritic soil, and limestone, at low elevations to 200 m (above sea level) or occasionally at mid-elevations 600 – 800 m (in the Horombe region; Fianarantsoa province).

Map 1.
figure 4

Distribution of A Hyperacanthus decaryi; B H. piliformis; C H. septentrionale; D H. sofikomba.

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Taxonomic Treatment

Key to deciduous species of Hyperacanthus (the sofikomba alliance)

  • 1a. Shrub to small tree, 1.5 – 5 m tall; branchlets glabrous; leaf abaxial surface glabrous, domatia absent; occurring mainly in Toliara and Fianarantsoa (Ihorombe region) provinces ……………………………………………………….…….…….….H. decaryi

  • 1b. Small tree to medium tree, 5 – 15 m tall; branchlets glabrous to pubescent; leaf abaxial surface glabrous to puberulous, domatia present; occurring in Mahajanga and Antsiranana provinces ...........……………………………………………………………2

  • 2a. Leaf abaxial surface puberulous, domatia pubescent; calyx tube puberulous to pubescent; corolla tube puberulous; occurring in Mahajanga province …………….…..H. piliformis

  • 2b. Leaf abaxial surface glabrous, domatia glabrous; calyx tube glabrous; corolla tube glabrous; occurring in Antsiranana and Mahajanga provinces ……………….………….3

  • 3a. Branchlets rough to corky, light brown; leaf blades orbicular to ovate, 40 – 65 × 35 – 50 (– 60) mm, midrib glabrous on lower (abaxial) surface; calyx tube 4 – 5 mm long; hypanthium 3 – 4 × 1.5 – 2.2 mm, slightly ribbed, densely pubescent; fruit globose to ovoid, slightly rough; occurring in Antsiranana province ……………H. septentrionale

  • 3b. Branchlets smooth, grey; leaf blades orbicular to broadly ovate, (15 –) 20 – 30 (– 45) × (15 –) 24 – 35 mm, midrib pubescent to glabrous on lower (abaxial) surface; calyx tube 1.5 – 3 mm long; hypanthium 1.5 – 2.5 × 1 – 1.5 mm, smooth, glabrous; fruit obovoid to ovoid, smooth; occurring in Mahajanga province ………………………H. sofikomba

1. Hyperacanthus decaryi Rakotonas. & A.P.Davis sp. nov. Type: Madagascar, Toliara province, RN 10, route between Beloha and Tsihombe, 6 Dec. 2008 (fl.), Rakotonasolo, Letsara & Miadana 1202 (holotype TAN; isotypes CAS, K).

http://www.ipni.org/urn:lsid:ipni.org:names:77335478-1

Small tree or shrub, 1.5 – 5 (– 8) m high, dbh 2 – 6 cm. Bark mottled, smooth, grey. Branchlets 3 – 6 mm in diam., smooth, grey to dark brown, glabrous. Brachyblasts (2 –) 5 – 15 (– 20) mm long, 1.5 – 3.5 mm in diam., base glabrous, apex pubescent. Stipules triangular to ovate, 2 – 3.5 (– 5) × 1.5 – 3 (– 4.5) mm, external surface pubescent. Leaves: petiole (8 –) 15 – 20 (– 25) mm long, brown to dark brown, puberulous when young, glabrous at maturity. Leaf blades orbicular to ovate, (12 –) 17 – 35 (– 42) × (15 –) 20 – 30 (– 35) mm, chartaceous-subcoriaceous, base truncate to obtuse, apex rounded to apiculate; abaxial surface glabrous, green, midrib slightly to prominent, pubescent or glabrous, secondary nerves manifest to prominent, 4 – 6 (– 7) pairs, ascending at an angle of 30 – 45°, eucamptodromous to cladodromous, tertiary nerves slightly obscure to obscure, reticulodromous; adaxial surface brown (when dry), glabrous, nerves manifest to obscure; domatia absent. Flowers (5 –) 6 – 8 (– 9)-merous, sessile to shortly pedicellate; calyx tube cylindrical to broadly infundibular, 2.5 – 4.5 (– 6) × (1.8 –) 2.5 – 3.8 mm, glabrous; calyx lobes (0.5 –) 1 – 2.5 × (0.5 –) 1 – 2 mm, apices acute, glabrous; corolla (25 –) 35 – 50 (– 60) mm long, white, glabrous on both surfaces; corolla tube infundibular, (20 –) 30 – 40 (– 45) mm long, (2 –) 3 – 4.2 mm in diam. at the throat; corolla lobes (7 –) 10 – 16 × (4 –) 6 – 8 mm, apices acute; disc 0.5 – 1 mm high, 1.5 – 2 mm in diam.; anther sacs 4 – 6.5 × 0.5 – 0.8 mm; ovary and hypanthium narrowly ovoid to cylindrical-ovoid, 2.5 – 4.5 × 1.5 – 2.8 mm, puberulous to pubescent; style 32 – 38 × 0.5 – 1 mm, glabrous; stigma lobes obovate to linear, (3.5 –) 6 – 9 × (1 –) 1.5 – 2.5 mm, slightly exserted, apices acute to obtuse. Fruit globose to broadly ovoid, 10 – 17 (– 25) × 8 –14 (– 18) mm, smooth, glabrous, puberulous when young. Seeds unknown.

recognition. Hyperacanthus decaryi falls in the sofikomba alliance, which can be distinguished from other members of Hyperacanthus by its deciduous habit. Hyperacanthus decaryi differs from species of the sofikomba alliance by having, glabrous branchlets, leaves without domatia and a glabrous lower (abaxial) surface, and flowers with 6 – 8 corolla lobes, exceptionally 9 or 5.

distribution. Endemic to the southern and southwestern regions of Madagascar, in Fianarantsoa and Toliara provinces (Map 1A).

specimens examined. Fianarantsoa province: Ihosy, road from Ihosy to Farafangana (9 km before Ihosy), c. PK 52, 30 Jan. 2006 (fr.), De Block 1955 (BR, K, MO, P, TAN, USP); Ihosy, restes des forêts de la vallée de la Menarahaka entre Ihosy et Ivohibe, au sud de Menarahaka, Tsimirimbo, 30 Oct. 1960 (fl.), Leandri 3463 (P); Ihosy, restes des forêts de la vallée de la Menarahaka entre Ihosy et Ivohibe, au sud de Menarahaka, Tsimirimbo, 30 Oct. 1960 (fl.), Leandri 3469 (P, TAN); loc. cit., 30 Oct. 1960 (fl.), Leandri 3475 (P); Ihosy, Menarahaka, 18 March 1955 (fr.), coll. ignot. 3786-SF (P); Ihosy, Sakalalina, Tsimirombo, Menarahaka, Analavoka, 18 March 1953 (fr.), coll. ignot. 13786-SF (P, TEF); Ihosy, entre km 12 et 13, route Ihosy–Ivohibe, à 500 m au nord de la route, sine date (st.), coll. ignot. 221 R1 (TEF); Ihosy, vallée de la Menarahaka (bassin du Mananara), 31 Oct. 1924 (fl.), coll. ignot. 3028-SF (P, TAN); Ihosy, environs d'Ihosy (centre sud), March 1934 (st.), Humbert 14468-bis (P). Toliara province: Fort-Dauphin, (Taolanaro), réserve naturelle intégrale d'Andohahela, parcelle nº 2, piste d'Ambatoabo, 16 March 1994 (fr.), Andrianarisata et al. 72 (P); Toliara II, Imanombo (centre sud), Oct. 1956 (y fr.), Bosser 10253 (P, TAN); Taolanaro, Andohahela réserve naturelle intégrale, parcelle 2, c. 50 km WNW (BRG 295º) of Taolanaro (Fort Dauphin), forest c. 2 km due E of Ihazofotsy, 30 Nov. 1997 (y fr.), Davis 1168 (P, TAN); Ambovombe, 28 Aug. 1924 (fl.), Decary 3089 (P); Antanimora, 11 July 1926 (fl.), Decary 4305 (P); Ambovombe, vallée de l'Ikonda au nord d'Ambovombe, 2 May 1931 (fl.), Decary 8926 (P); Ambovombe, au nord-ouest d'Ambovombe, 25 Sept. 1931 (fl.), Decary 9196 (P); Betroka, Beteny, limite nord-est de l'Androy, 22 Nov. 1931 (fl.), Decary 9336 (P); Betroka, Beteny, limite nord-est de l'Androy, 22 Nov. 1931 (fl.), Decary 9338 (P); Betroka, Beteny, limite nord-est de l'Androy sur des gneiss, 22 Nov. 1931 (fl.), Decary 9339 (P); Betioky, vallée de la Sakoa, 21 Oct. 1940 (fl.), Decary 15980 (P); Toliara, 1 Jan. 1956 (fr.), Descoings 1432 (TAN); Toliara II, road from Tulear to Ankilimanilika, 36.6 km N of Tuléar, 22 March 1985 (fr.), Dorr et al. 4119 (MO, P, TAN); Ranopiso, Ambatoabo, Vohidafa, forêt sèche de la réserve naturelle intégrale d'Andohahela, 2 Nov. 1994 (fl.), Eboroke 916 (MO, P, TAN); Toliara II, environs de Tuléar, delta du Fiherenana, 14 – 26 Sept. 1924 (fl.), Humbert 2418 (P, TAN); Toliara II, forêt de Besomaty entre le Fiherenana et l'Isahaina (Mangoky), 1 Oct. 1933 (fl.), Humbert 11271 (P); Toliara II, forêt d'Ampihamy au NE de Manombo (sud-ouest), 1 Oct. 1933 (fl.), Humbert 11508 (P); Amboasary, vallée moyenne du Mandrare près d'Anadabolava, Dec. 1933 (fr.), Humbert 12444 (P); Amboasary, vallée de la Manambolo, rive droite (bassin du Mandrare) aux environs d'Isomono (confluent de la Sakamalio) Mont Morahariva, Dec. 1933 (fr.), Humbert 13123 (P); Toliara II, bassin de la Malio (affluent de Mangoky), près d’Ambalabe, 23 – 27 Nov. 1946 (fr.), Humbert 19380 (P, TAN); Toliara II, environs de Manombo (sud-ouest), Isonto à l'ouest d'Ankililoaka, 28 Jan. 1947 (fr.), Humbert 20050 (P); Toliara II, plateau calcaire à 39 km de Tuléar, 1 March 1960 (st.), Keraudren et al. 544 (P); Morondava, route entre Morondava à Belo, 3 Dec. 1970 (y fr.), Keraudren et al. 25904 (P); Toliara II, 20 Feb. 1940 (fl.), Lam & Meeuse 5432 (P); Manja, N of Toliara, in forêt de Mikea, 23 – 25 road km W of Vorehe, 8 Feb. 1998 (fr.), McPherson et al. 17318 (MO, P, TAN); loc. cit., 12 Feb. 1998 (fr.), McPherson 17414 (MO, TAN); Taolanaro, réserve naturelle intégrale d'Andohahela, parcelle 2, 7.5 km de Hazofotsy, 8 Dec.1995 (fl.), Messmer et al. 64 (TAN); Betioky, Beza Mahafaly reserve, near Betioky, parcelle 2, 23 Oct. 1987 (fr.), Phillipson 2440 (MO, P, TAN); Beraketa, 15.6 km S of Beraketa on route nationale 13, series of low rock outcrops, 19 March 1992 (fl.), Phillipson 3947 (MO, TAN); Toliara II, bas Fiherenana, 20 March 1923 (fl.), Poisson 667 (P); Tsihombe, route between Tsihombe and Beloha, 6 Dec. 2008 (fl.), Rakotonasolo et al. 1202; Toliara II, route d'Ifaty, sol sableux, 1 April 1968 (fr.), Rakotozafy 751 (TAN); Betioky, commune Betioky, Fokontany Ambatofola Est, forêt à 8 km d'Ambatofolia, Anjanany, 11 Jan. 2003 (fr.), Randrianaivo 921 (MO, P, TAN); Sakaraha, Zombitse–Vohibasia, National Park, Isoko, the west part of Isoky, 4 Dec. 2003 (fr.), Razafimandimbison et al. 497 (TAN); Bekily, environs d'Ampandrandava (entre Bekily et Tsivory), rochers de Pisopiso, Nov. 1943 (fl.), Seyrig 329 (P); Tranoroa, Sud, collines gneissiques de Maroakoho, rive droite de la Manarandra, près de Tranoroa, 14 Nov. 1967 (fr.), Capuron 21969-SF (P); Toliara II, Sud (Ouest); sur la route de Manombo, au nord du Fiherenana, 8 – 12 Nov. 1967 (fl.), Capuron 27921-SF (P, TEF); Amboasary, Berenty (vallée de Mandrare), 17 Feb. 1949 (y fr.), coll. ignot. 416-SF (P, TEF); Sakaraha, 6 Feb. 1951 (fr.), coll. ignot. 2842-SF (P, TAN, TEF); Amboasary, Behara, RN XI, 23 Nov. 1951 (fl.), coll. ignot. 3459-SF (P, TAN); Toliara II, Anketa, 29 Jan. 1952 (fr.), coll. ignot. 4561-SF (P, TAN, TEF); Amboasary, Behara, 14 Oct. 1954 (fl.), coll. ignot. 6744-RN (P, TEF); Betroka, Isantsy, 28 March 1954 (fr.), coll. ignot. 9332-SF (P, TEF); Bekily, Belinda, forêtd’Anja au sud du village, 26 March 1954 (fr.), coll. ignot. 9665-SF (P, TEF); Manja, Beharona, forêt Troboampamaky au sud du village d’Ambatrinaly, 14 March 1954 (fr.), coll. ignot. 9821-SF (P, TEF); Ambovombe, Anjamalangy, Mpanavy–Antanimora, 5 March 1954 (fr.), coll. ignot. 11129-SF (P, TEF); Toliara II, Analabe, Tampibato, 18 Jan. 1955 (fr.); coll. ignot. 31465-SF (TEF), Ampanihy, Maroakoho, 14 Nov. 1964 (fr.), coll. ignot. 12811-SF (P, TEF); Morondava, forêt de Marosalaza, 50 km au nord de Morondava, 9 May 1974 (st.), Abraham 104 (P); Morondava, forest N of Morondava, 5 Jan. 1996 (fr.), Jongkind 3653 (TAN, WAG); Morondava, route entre Morondava à Belo, 3 Dec. 1970 (fr.), Keraudren et al. 25904 (P, TAN); Morondava, sine date (fr.), Rahantamalala 204 (P); Belo sur Tsiribihina, Marotaolana, 13 March 1955 (fr.), coll. ignot. 13250-SF (P, TEF); Morondava, Befasy, Tanambao, 8 Feb. 1956 (fr.), coll. ignot. 15553-SF (P, TEF); Morondava, Analaiva, Ankirijifoty, 27 Jan. 1957 (fr.), coll. ignot. 16635-SF (P, TEF); RN 10, route between Beloha and Tsihombe, 6 Dec. 2008 (fl.), Rakotonasolo, Letsara & Miadana 1202 (CAS, K, TAN).

habitat. Deciduous, seasonally dry forest, xerophytic bush or spiny forest; reddish brown sand or gneissic rock or lateritic soil, or sandy soil on limestone; 30 – 600 (– 800) m elevation.

conservation status. Least Concern (LC). The extent of occurrence (EOO) of Hyperacanthus decaryi is estimated to be 121,824 km2 and the area of occurrence (AOO) 204 km2 (using a cell width of 2 km). This species occurs in more than 25 locations, with nine of the subpopulations in protected areas (Reserve Naturelle Integrale d’Andohahela, Zombitse-Vohibasy National Park, Mikea National Park, Beza Mahafaly Reserve, and Manombo new protected area). Although this is a relatively common species, its habitats are threatened by slash and burn agriculture, uncontrolled fires, mining, illegal logging, and charcoal production.

phenology. Flowering time: October – December, rarely July – September; fruiting time: December – April, rarely October or November.

etymology. Hyperacanthus decaryi is dedicated to the French botanist Raymond Decary, who collected more specimens of this species than any other collector and undertook extensive fieldwork in southern Madagascar.

vernacular names. Fandimbitritry (13786-SF); Latakompamboly (3459-SF); Refeko (16695-SF); Sarigiavy (Humbert 13123); Sarivandrika (2842-SF); Tainoro (11129-SF, 9655-SF); Tenoro (67444-RN); Velanjioke (12811-SF); Volatsiva (9332-SF); Voligeja (4561-SF); Voligeza (4561-SF); Volivaza (2842-SF).

uses. Construction wood for houses, cattle and house enclosures, and firewood. The fruits are eaten by lemurs and children.

2. Hyperacanthus piliformis Rakotonas. & A.P.Davis sp. nov. Type: Madagascar, Mahajanga, Boriziny, Bongolava protected area, Andranomena, Betotaky, 19 Nov. 2020 (fl.), Rakotoarison et al. 1292 (holotype TAN; isotypes BR, K, MO, P).

http://www.ipni.org/urn:lsid:ipni.org:names:77335479-1

Tree, 5 – 15 m high, dbh up to 16 cm. Bark mottled, slightly verrucose, silvery grey to dark brown when old. Branchlets slightly verrucose, 3 – 6 mm in diam., grey to beige, pubescent on young branchlets. Brachyblasts 5 – 12 mm long, 2 – 3.5 mm in diam., slightly verrucose, apex pubescent to puberulous. Stipules triangular, 3 – 6 × 1.5 – 2 mm, external surface pubescent. Leaves: petiole (10 –) 18 – 30 mm long, dark grey to brown, pubescent to puberulous; leaf blades reniform to very broadly ovate, (25 –) 45 – 60 × (25 –) 35 – 50 mm, chartaceous, sometimes concolorous, base rounded to truncate, apex obtuse or rounded to apiculate; abaxial surface pubescent, beige to dark brown, midrib prominent, secondary nerves prominent, pubescent, 5 – 7 pairs, ascending at an angle 30 – 45°, eucamptodromous to cladodromous, tertiary nerves slightly prominent to obscure, slightly reticulodromous; adaxial surface puberulous, dark brown (when dry), nerves slightly distinct to obscure; domatia present at the base of secondary nerves. Flowers (5 –) 6 – 7-merous, sessile; calyx tube cylindrical to infundibular, 3 – 4.5 × 2.5 – 3.5 mm, pubescent to puberulous; calyx lobes ovate to deltate, 1 – 1.5 × 1 – 1.5 mm, apices acute, puberulous; corolla 40 – 50 mm long, puberulous, greenish to white; corolla tube infundibular, 30 – 40 (– 45) × 1 – 1.8 mm, 3.5 – 5 mm in diam. at the throat, outside surface puberulous, inside surface glabrous; corolla lobes elliptic, 12 – 16 × 6 – 9 mm, apices acute to obtuse, surfaces glabrous; disc 1 – 1.4 mm high, 2.8 – 3.5 mm in diam.; anthers 7 – 8 × 0.5 – 0.8 mm, semi-exserted; ovary and hypanthium cylindrical-ovoid, 1.3 – 2 × 1 – 1.5 mm, densely pubescent; ovules numerous; style 38 – 42 × 1 – 1.2 mm, stigma lobes elliptic, 8 – 10 × 2.8 – 3.5 mm, semi-exserted, apices acute. Fruit obovoid to ovoid, 25 – 35 × 18 – 25 mm, smooth, pubescent to puberulent. Seeds lenticular, 4 – 5 × 2.5 – 3.5 × 1.2 – 1.5 mm.

recognition. Hyperacanthus piliformis falls in the sofikomba alliance, which can be distinguished from other members of Hyperacanthus by its deciduous habit. Hyperacanthus piliformis differs from other species of the sofikomba alliance, by most parts being puberulous, including lower leaf surface, domatia, external surfaces of calyx and corolla tube (vs flower and fruits glabrous in other species, apart from the hypanthium), and pubescent fruits (vs glabrous).

distribution. Endemic to western Madagascar, in Mahajanga (Boeny and Sofia regions) and Toliara provinces (Atsimo-Andrefana region) (Map 1B).

specimens examined. Mahajanga province: Soalala, réserve naturelle intégrale Namaroka (RN 8), c. 40 km (GPS) S of Soalala, 3 Feb. 2000 (fr.), Davis et al. 2532 (K, P, TAN); Maintirano, Oct. 1932 (fl.), Perrier de la Bathie 3920 (P); Soalala, Andranomavo, RN 8, 30 April 1952 (fr.), coll. ignot. 3903-RN (P); Soalala, Andranomavo, RN 8, 28 Oct. 1952 (fr.), coll. ignot. 4612-RN (P, TAN); Soalala distr., Andranomavo, Vilanandro, 8 Oct. 1971 (fl.), coll. ignot. 30846-SF (TEF); Port–Berge, Andranomeva, à l’est du village, 29 March. 1960 (fr.), coll. ignot. 19669 -SF (P, TEF); Port-Berge, Andranomena, 16 Jan. 2018 (fr.), Rabarijaona et al. MDG 105-006 (K, TAN); Port-Berge, Marosely, Bongolava PA, 30 Nov. 2017 (fl.), Rabarijaona et al. 686 (K, TAN); Boriziny, Bongolava protected area, Andranomena, Betotaky, 19 Nov. 2020 (fl), Rakotoarison et al. 1292 (BR, K, MO, P, TAN); Marovoay, Ankarafantsika National Park, 17 March 2020 (fr), Rakotonasolo 3028 (K, TAN).

habitat. Deciduous, seasonally dry forest on limestone or sand; 100 – 200 (– 750) m elevation.

conservation status. Endangered (EN) B2ab (i, ii, iii, iv). The extent of occurrence (EOO) of Hyperacanthus piliformis is estimated to be 84,762 km2 and the area of occurrence (AOO) 32 km2 (using a cell width of 2 km). This species occurs in three locations with all subpopulations occurring in protected areas (Reserve Integrale Namaroka, Bongolava new protected area, and National Park of Zombitse-Vohibasy). Even though it occurs in these protected areas, its habitat is still threatened by uncontrolled fires (bush fires) and illegal logging. Despite the extensive EOO, locations and subpopulations of this species are few, even though considerable fieldwork has been undertaken in western Madagascar.

phenology. Flowering time: October – November; fruiting time: November – April.

etymology. The specific epithet comes from the Latin adjective piliformis (bearing hairs).

vernacular names. Sofikomba (4612–RN) and Taly Naka (Phillipson 3102). Mantalagna (Rakotoarison et al. 1292).

uses. Unknown.

3. Hyperacanthus septentrionale Rakotonas. & A.P.Davis, sp. nov. Type: Madagascar, Antsiranana, Vohemar, Ampitsikina, Antsaharaingy, Antsapile, Andavavabatobe, au sud du village d'Ankaramy, 11 Nov. 2005 (fl.), Rakotonandrafara et al. 413 (holotype K; isotypes CNARP, G, MO, P).

http://www.ipni.org/urn:lsid:ipni.org:names:77335480-1

Small tree to tree, 4 – 8 (– 12) m high, dbh 8 – 10 (– 20) cm. Bark mottled, smooth, yellowish-grey to whitish. Branchlets 3.5 – 5 mm in diam., rough to slightly smooth, grey to light brown, glabrous. Brachyblasts 5 – 25 mm long, 2.5 – 3.5 mm in diam., rough to verrucose, glabrous from base to apex. Stipules triangular to deltate, 2 – 3 × 2 – 2.5 mm, external surface glabrous to slightly hairy. Leaves: petiole (10 –) 15 – 20 (– 30) mm long, very short when plants flowering, glabrous; leaf blades orbicular to ovate, 40 – 65 × 35 – 50 (– 60) mm, chartaceous-subcoriaceous, base truncate to rounded, apex rounded to broadly obtuse; abaxial surface, glabrous, grey to light brown, midrib prominent, glabrous, secondary nerves prominent, 4 – 6 pairs, ascending at angle 30 – 40°, eucamptodromous, tertiary nerves slightly distinct to obscure, reticulodromous; adaxial surface dark brown (when dry), glabrous, nerves slightly distinct to obscure; domatia present at the base of secondary nerves. Flowers 5 (– 6)-merous, sessile; calyx tube cylindrical to broadly infundibular, 4 – 5 × 2.5 – 3 mm, glabrous; calyx lobes elliptic to ovate, 1.8 – 2.5 × 1 – 1.5 mm, apices acute to acuminate, glabrous; corolla 30 – 50 mm long, white to greenish when fresh, both surfaces glabrous; tube infundibular, 20 – 35 × 1 – 1.5 mm, glabrous on both surfaces, 2 – 4 mm in diam. at throat; corolla lobes elliptic, 9.5 – 15 × 4 – 5 mm, membranous when dried, apex acute, glabrous on both surfaces; disc 0.8 – 1.2 mm high, 1.5 – 2.2 mm in diam.; stamens sessile, slightly exserted; anthers 5 – 6.5 × 0.7 – 0.9 mm; ovary and hypanthium cylindrical-ovoid, 3 – 4 × 1.5 – 2.2 mm, slightly ribbed, densely pubescent; style 30 – 40 × 0.8 – 1 mm, glabrous; stigma bifid, glabrous, lobes ovate, 2.5 – 3.5 × 1.8 – 2.4 mm, slightly exserted, apices acute to obtuse. Fruit globous to ovoid, 28 – 33 × 15 – 25 mm, slightly rough, glabrous. Seeds unknown.

recognition. Hyperacanthus septentrionale falls in the sofikomba alliance, which can be distinguished from all other members of Hyperacanthus by its deciduousness. Hyperacanthus septentrionale differs from H. piliformis by its glabrous leaves, flowers and fruits (vs puberulous or pubescent); from H. decaryi by its tree habit (vs shrub or small tree), and from H. sofikomba by its rough to corky branchlets (vs smooth), densely pubescent hypanthium (vs glabrous) and calyx tube 4 – 5 mm long (vs 1.5 – 3 mm long).

distribution. Endemic to western of Madagascar, in Antsiranana province (Map 1C).

specimens examined. Antsiranana province: Antsiranana II, Analamerana, bank of Irodo river, near Irodo camp, 6 Jan. 2002 (fr.), De Block et al. 1088 (BR, TAN); Ambilobe, Ankarana, road from Campement des Anglais towards Campement des Américains (not beyond first savanna), 13 Jan. 2002 (st.), De Block et al. 1197 (BR, MO, TAN); Ambilobe, Marivorahona, Ambilomagodro, Ampondrabe, à 7 km à l'est de Mahamasina–Ankarana, 10 Feb. 2006 (fr.), Randrianaivo et al. 1344 (MO, TAN); Vohemar, Ouest (nord): forêt d'Analafiana, au nord de la basse Manambery (au SW de Vohemar), 11 May 1967 (fr.), coll. ignot. 27510-SF (P, TEF); Vohemar, Ampitsikina, Antsaharaingy, Antsapila, Andavavabatobe, au sud du village d'Ankaramy, 11 Nov. 2005 (fl.), Rakotondrafara 413 (CNARP, G, MO, P, TAN).

habitat. Deciduous, seasonally dry forest on limestone or sand or lateritic soil, from 5 – 210 m elevation.

conservation status. Endangered (EN) B1ab(i, ii, iii, iv) & B2ab (i, ii, iii, iv). The extent of occurrence (EOO) of Hyperacanthus septentrionale is estimated to be 2,481 km2 and the area of occurrence (AOO) 32 km2 (using a cell width of 2 km). This species occurs in five locations and four subpopulations occur in protected areas (Reserve Naturelle Integrale d’Analamerana, Reserve Naturelle Integrale d’Ankarana and Loky Manambato new protected area). Its habitats are threatened by slash and burn agriculture, uncontrolled fires, illegal logging, artisanal mining and charcoal production.

phenology. Flowering time: November; fruiting time: December – May.

etymology. The specific epithet refers to the distribution in the northern part of Madagascar.

vernacular name. Sofinakomba (27510-SF, Rakotondrafara 413).

uses. Construction wood for houses.

4. Hyperacanthus sofikomba Rakotonas. & A.P.Davis sp. nov. Type: Madagascar, Mahajanga province, Melaky region, Maintirano distr., Belitsaka, Beanka, Ambinda, Ankazoteva, 28 Oct. 2008 (fl.), Rakotonasolo, Andriamihajarivo, Razakamalala & Letsara 1466 (holotype TAN; isotype CAS, K, MO).

http://www.ipni.org/urn:lsid:ipni.org:names:77335481-1

Small tree to tree, (3 –) 5 – 8 (– 10) m high, dbh (2 –) 5 – 8 cm. Bark mottled, smooth, grey to brown. Branchlets 4 – 6 mm in diam., smooth, grey, glabrous. Brachyblasts 5 – 15 mm long, 1.5 – 3.5 mm in diam., base glabrous, apex pubescent. Stipules triangular, 1.5 – 2 × 1 – 1.5 mm, external surface puberulous. Leaves: petiole (7 –) 10 – 15 (– 20) mm long, brown, glabrous; leaf blades orbicular to broadly ovate, usually reniform, (15 –) 20 – 30 (– 45) × (15 –) 24 – 35 mm, chartaceous-subcoriaceous, base slightly reniform, rounded to obtuse, or acute, apex acute to apiculate; abaxial surface slightly green to brown, glabrous, midrib prominent, pubescent or glabrous, secondary nerves prominent, 3 – 5 pairs, ascending at an angle 45 – 50°, cladodromous, tertiary nerves slightly distinct, reticulodromous; adaxial surface brown, glabrous, nerves slightly distinct to obscure; domatia present at the base of secondary nerves. Flowers 5 (– 6)-merous, shortly pedicellate or sessile; calyx tube cylindrical to broadly infundibular, 1.5 – 3 × 1.8 – 2.2 mm, glabrous; calyx lobes ovate to deltate, 0.2 – 0.5 × 0.2 – 0.5 mm, apices apiculate, glabrous; corolla (30 –) 35 – 45 (– 50) mm long, white, glabrous; corolla tube infundibular, 25 – 30 (– 40) × 1 – 1.5 mm, glabrous on both surfaces, 2 – 3 mm in diam. at the throat; corolla lobes elliptic to obovate, 10 – 14 × 5 – 8 mm, apices acute, surfaces glabrous; disc 1 – 1.4 mm high, 1.4 – 1.8 mm in diam.; stamens sessile, slightly exserted; anthers linear, 4 – 5 × 0.5 – 0.7 mm; ovary and hypanthium ovoid, 1.5 – 2.5 × 1.3 – 1.9 mm, glabrous; style 33 – 44 × 0.8 – 1 mm, glabrous; stigma bifid, glabrous, lobes broadly ovate,1 – 1.5 × 1 – 1.2 mm, exserted, apices obtuse. Fruit obovoid to ovoid, (15 –) 20 – 30 (– 35) × (12 –) 15 – 20 (– 25) mm, smooth, glabrous. Seeds lenticular, c. 3 per fruit, 4 – 4.5(– 6) × 3 – 3.8 × 1.5 – 2 (– 2.5) mm. Fig. 2.

recognition. Hyperacanthus sofikomba falls in the sofikomba alliance, which can be distinguished from all other species of Hyperacanthus by its deciduous habit. Hyperacanthus sofikomba differs from other members of the sofikomba alliance by its usually reniform (kidney-shaped) leaves, having domatia and glabrous hypanthium.

distribution. Endemic to the western Madagascar, in Mahajanga province (Map 1D).

specimens examined. Mahajanga province: sine date, Aubreville (3-RN) (P); Marovoay, poste forestier d'Ampijoroa, Jardin Botanique (n° 4, série A), 22 Feb. 1985 (fr.), Barnett et al. 467 (P, TAN); Marovoay, réserve naturelle intégrale Ankarafantsika, station forestière d'Ampijoroa, trail C, en route to Jardin Botanique, 24 Jan. 2002 (fr.), Davis et al. 2503 (K, TAN); loc. cit., 24 Jan. 2002 (fr.), Davis et al. 2511 (K, P, TAN); Mahajanga II, station forestière Antsanitia, c. 20 km (GPS) NE of Mahjanga, 26 Jan. 2000 (fr.); Soalala, en route to réserve naturelle intégrale Namaroka, near the village of Ankerika, c. 24 km (GPS) due S of Soalala, fragment of deciduous, 6 Feb. 2000 (fr.), Davis et al. 2543 (K, P, TAN); Marovoay, Ampijoroa forestry station, Jard. Botanique, section B, 9 Feb. 1999 (fr.), De Block et al. 770 (BR, K, MO); Marovoay, poste forestier d'Ampijoroa, Jardin Botanique (n° 4, série A), 22 Feb. 1985 (fr.), Door et al. 3765 (MO, P, TAN); Port–Berge, 40 km of Port Berge, 15 May 1974 (st.), Gentry et al. 11784 (MO, TAN); Marovoay, Ankarafantsika, Ampijoroa forestry station, 8 April 1988 (st.), Gentry et al. 62115 (MO, TAN); Marovoay, Ampijoroa forest station, 15 Feb. 1987 (fr.), Nicoll 381 (P, TAN); Ouest: Soalala (Ambongo), 1 Sept. 1903 (fr.), Perrier de la Bathie 1625bis (P); Ouest: Ankirihitra, près de Tsitondroina, Déc. 1900 (fr.), 1625 (P); Ouest: Maintirano, 1 Oct. 1928 (fl.), Perrier de la Bathie 3521 (P); Ouest: Port–Berge, Bongolava, 1 Aug. 1907 (fl.), Perrier de la Bathie 3617 (P); Ouest: Port–Berge, Bongolava, 1 Jan. 1907 (fr.), Perrier de la Bathie 3687 (P); Ouest: Mahajanga, 1 Jan. 1920 (fr.), Perrier de la Bathie 13440 (P); Ambongo, 13 Feb. 1841 (fr.), Pervillé 582 (P); Boriziny, Bongolava protected area, Ankoditrihazo, 18 Nov. 2020 (fl.), Rakotoarison et al. 1228 (K, TAN); Boriziny, Bongolava protected area, Befotaka, 19 Nov. 2020 (fl), Rakotoarison et al. 1297 (K, TAN); Marovoay, station forestière d'Ampijoroa, piste botanique ouest, 8 March 1996 (fr.), Rakotomalaza et al. 632 (MO, TAN); Morovoay, Ankarafantsika, Ampijoroa, Jardin Botanique A, 6 Jan. 2000 (fr.), Rakotonasolo 124 (K, MO, P, TAN); Maintirano, Belisaka, Beanka, 28 Oct. 2009 (fl.), Rakotonasolo 1466 (CAS, MO, P, TAN); Boriziny, Bongolava protected area, Antanivaky, Antanimalandy, 20 Oct. 2020 (fl. & fr.), Rakotonasolo et al. 3183 & 3194 (K, TAN); Mahajanga II, comune Belobaka, station forestière d’Antsanitia, à 18 km au nord de Mahajanga, 7 March 1999 (fr.), Randrianaivo et al. 380 (P, TAN); Ankarafantsika, on trails W of Ampijoroa forest station, c. 4 km W of Andranofasika and c. 120 km E of Mahajanga, 14 Dec. 2003 (fr.), Razafimandimbison 547 (TAN); Ambato–Boeni, Tsaramanondroso, Bevazaha, 27 July 1948 (fl.), coll. ignot. 1631-RN (P); Ambato–Boeni, Tsaramanondroso, Ankarafantsika, 4 Jan. 1950 (fl.), coll. ignot. 2027-RN (P); Antsalova, 10 Jan. 1962 (fr.), coll. ignot. 12472-RN (P, TAN, TEF); Analalava, ouest: environs d'Antsangabe (au sud d'Ambondro–Ampasy, canton d'Antonibe), 4 Nov. 1958 (fl.), Capuron 18870-SF (P, TAN, TEF); Mitsinjo, Ouest (Ambongo), partie nord de la forêt de Tsiombikibo, au sud du Cap Tanjona, 19 Nov. 1956 (fl.), Capuron 24222-SF (P, TAN, TEF); Marovoay, Ankarafantsika (7e réserve), plateau–pentes, argileux, petite Cascade, sine date (fl. Sept., fr. Oct. – Nov.), coll. ignot. 3-SF (P); Marovoay, Tsimaloto (7e réserve), plateau, sine date (fr.), coll. ignot. 32-SF (P, TAN); Ambato–Boeni, Bevazaha, 3 Nov. 1950 (fl.), coll. ignot. 1746-SF (P, TEF); Marovoay, Réserve forestière d’Ankarafantsika, 17 Nov. 1950 (y fr.), coll. ignot, 2211-SF (P, TEF); Ambato–Boeni, Tsaramandroso, Manaratsandry, 25 April 1952 (fr.), coll. ignot. 4944-SF (P, TEF); Marovoay, Ampijoroa, 30 Dec. 1952 (fr.), coll. ignot. 7181-SF (P); Marovoay, Ampijoroa, J.B. 4, section B, 17 Dec. 1953 (fr.), coll. ignot. 8098-SF (P, TEF); Marovoay, Ampijoroa, 14 March 1954 (fr.), coll. ignot. 9625-SF (P); Ambato–Boeni, Sitampiky, Andafia, forêt de Maroaboaly, 3 March 1957 (fr.), coll. ignot. 17761-SF (TEF); Maevatanana, Kandreho, Tsindinondry, Antaliha, crête sur sol calcaire, 12 Feb. 1952 (fr.), coll. ignot. 19039-SF (P); Ambato–Boeni, Antranovato, 20 Jan. 1959 (fr.), coll. ignot. 19262-SF (P, TEF); Port–Bergé, Andranomeva, 29 March 1960 (fr.), coll. ignot. 19669-SF (TEF); Befandriana–Nord, Tsarahonenana, 17 March 1960 (fr.), coll. ignot. 19689-SF (TEF); Marovoay, Tsaramandroso, Ampijoroa, forêt tropohile à l’ouest de la station, 27 Feb. 1980 (fr.), coll. ignot. 29747-SF (TEF); Soalala, Vilanandro, 8 Oct. 1971 (fl.), coll. ignot. 30846-SF (TEF); Ambato–Boeni, Tsaramandroso, Andranofasika, Ambongamaranitra, 15 Feb. 1987 (fr.), coll. ignot. 31251-SF (TEF); Marovoay, Ampijoroa, plateau, 10 Nov. 1987 (fr.), coll. ignot. 31836-SF (TEF); Marovoay, Ampombilava, Ankarafantsika, Ampijoroa, J.B. 4, 6 Feb. 1994 (fr.), coll. ignot. 33935-SF (TEF); Marovoay, Andranofasika, Ampombilava, Ampijoroa, Jardin Botanique, 15 Dec. 1991(fr.), coll. ignot. 34341-SF (TEF); Marovoay, Andranofasika, Ampijoroa, J.B. A, 23 Jan. 1992 (fr.), coll. ignot. 34356-SF (TEF); Marovoay, Parc National d’Ankarafantsika, station d’Ampijoroa, Feb. 2000 (fr.), coll. ignot. 35157-SF (TEF); coll. ignot. 7182-SF (P, TEF), Marovoay, J.B. 4, Ampijoroa, 30 Dec. 1952 (fr.); Mahajanga II, Marohogo, forêt domaniale d'Ankarandoha à l’est du village d’Andranoboaka et d’Ambalabe, 18 June 1954 (fr.), coll. ignot. 28 R151 (P, TEF); Bealanana, 14 March 1954 (fr.), coll. ignot. 8R287 (TEF); Anjiamanitra, 20 April 1951 (fr.), coll. ignot. 67R174 (TEF); Antsohihy, Anjimangirana, Andalirana, forêt sèche claire d’Ambohaliabe, 15 Dec. 1954 (fr.), coll. ignot. 79 R78 (TEF); Marovoay, Ampijoroa, sur ligne sommière de l’école forestière, J.B. 4, section A, 14 March 1954 (fr.), coll. ignot. 22 R250 (TEF); forêt côtière près de Soahanina, 23 Nov. 1952 (fr.), Leandri 2227 (P, TAN); Maevatanana, Kandreho, Tsindinondry, Antaliha, 12 Feb. 1958 (fr.), coll. ignot. 19039-SF (P, TEF); Befandriana–Nord, Tsarahonenana, Andrafiabe, entre villages Andrafiabe et Ambato, au bord du sentier, 6 May 1958 (fr.), coll. ignot. 19069-SF (P, TEF, TAN); Befandriana–Nord, Tsarahonenana, Andrafiatsra, 17 March 1960 (fr.), coll. ignot. 19689-SF (P, TEF); Port-Berge, Bemololo, Bongolava PA, 17 Jan. 2018 (fr.), Rabarijaona et al. MDG 105-023 (TAN), Melaky region, Maintirano distr., Belitsaka, Beanka, Ambinda, Ankazoteva, 28 Oct. 2008 (fl.), Rakotonasolo, Andriamihajarivo, Razakamalala & Letsara 1466 (CAS, K, MO, TAN).

habitat. Deciduous, seasonally dry forest, littoral forest and scrubland on white or brown sand or sand soils; 5 – 250 m elevation.

conservation status. Least Concern (LC). The extent of occurrence (EOO) of Hyperacanthus sofikomba is estimated to be 66,627 km2 and the area of occurrence (AOO) of 128 km2 (using a cell width of 2 km). This species occurs in more than 15 locations and three subpopulations occur in protected areas (Ankarafantsika National Park, Beanka and Bongolava new protected areas). Despite its presence in these protected areas, its habitats are threatened by slash and burn agriculture, uncontrolled fires, illegal logging and charcoal production.

phenology. Flowering time: October – November; fruiting time: November – April.

etymology. The specific epithet comes from its vernacular name.

vernacular names. Andronosy (Perrier de la Bathie 1625); Lamotimboay (Rahantamalala 204); Malamasafohy (3-RN); Mantalana (79R174); Mantalany (8R174); Sofikomba (Davis 2443, Davis 2511, 9625-SF, 22R250, 34341-SF, 7182-SF); Sofinankomba (2027-RN, 1746-SF, 18870-SF, 31251-SF); Tainoro (29747-SF); Tanatsobaka (2211-SF); Tanatsovaka (19262-SF); Taonoly (32-SF).

uses. Construction wood for houses, cattle and house enclosures, firewood. Its fruits are eaten by lemurs and children.