Monanthotaxis maputensis P.H.Hoekstra, 2016

Hoekstra, Paul H., Wieringa, Jan J. & Chatrou, Lars W., 2016, A nonet of novel species of Monanthotaxis (Annonaceae) from around Africa, PhytoKeys 69, pp. 71-103 : 89-93

Monanthotaxis maputensis P.H.Hoekstra sp. nov. Figs 11 , 12 , Table 4

Type.

MOZAMBIQUE. Maputo, Moamba, Chinhanguanine, margem esquerda do rio Incomati , 14 December 1979, J. de Koning 7766 (holotype: WAG [WAG0349310!]; isotypes: MO [3880761!], LMA) .

Diagnosis.

Closely related to Monanthotaxis caffra (Sond.) Verdc., but differs in having long filaments which occupy more than half of the total stamen length, while Monanthotaxis caffra has short filaments and the anther cells occupy more than half of the total stamen length. Further Monanthotaxis maputensis has shorter and less hairy leaves, the fruiting pedicels are more slender and the stipes are shorter than with Monanthotaxis caffra .

Description.

Shrub, scandent shrub or liana, to 10 m tall, diameter to 3 cm; young branches reddish brown, with scattered appressed or erect light-brown hairs 0.4 mm long, quickly glabrescent, old branches dark brown with (whitish) lenticels. Leaves: petioles 2-4 × 0.7-1 mm, grooved adaxially, indumentum as branches; leaf lamina 2.8-6.7(-8.1) × 1.5-3.3 cm, length:width ratio 1.6-2.7(-3.3), elliptic to ovate or slightly obovate, base cuneate to rounded, with slightly thickened margins, apex obtuse to acute, chartaceous/coriaceous, discolorous, upper side shiny dark-green, lower side glaucous to light green, upper side soon glabrescent, lower surface with appressed yellowish/light brown hairs 0.2 mm long, glabrescent, venation eucamptodromous, midrib yellowish or reddish, secondary veins 5-8, from base curving upwards, tertiary venation reticulate, raised adaxially and slightly abaxially, or not visible abaxially, often pellucid-punctate. Inflorescences leaf-opposed, composed of a solitary flower or a 2-3 flowered rhipidium; sympodial rachis 0-3 mm; flowering pedicels 6-14 × 0.3-0.4 mm, glabrescent; lower bracts broadly ovate, 1.5 × 1.4 mm; upper bracts broadly triangular to ovate, placed near middle of pedicel, 0.5 × 0.5 mm; flower buds ovate, dried greyish yellowish with yellow margins. Flowers bisexual; receptacle 2-3 mm in diameter, flat, with short brown hairs between the carpels and stamens; sepals 3, 0.5-0.7 × 1.5-2 mm, broadly ovate, with short reddish brown pubescence near the margins, apex obtuse; petals pale yellowish to yellow, inside drying reddish brown to purple. 6 in two whorls; outer petals, 2.5-4 × 3.2-4 mm, broad ovate, shortly pubescent with yellowish hairs on the outside, more densely pubescent near margins, inside densely pubescent at the apex; inner petals, 3.0-3.4 × 1.7-2.2 ovate to elliptic, outside and inside pubescent at apex; stamens 12-15 in one or two whorls, free, obconic to clavate, 0.8-1.2 mm long, filaments 0.4-0.8 mm long, anthers latrorse, theca 0.3-0.5 mm, connective glabrous, truncate, staminodes 0; carpels 10-13, 1.2-1.6 × 0.4-0.5 mm, subcylindric to ellipsoid, glabrous except for some hairs at the base, 1 (-2) ovules, stigma elongate, 0.3-0.4 mm long, grooved, glabrous. Fruits: pedicels 8-14 × 0.4-0.9 mm; sepals persistent; stipes 2.5-4.0 mm long, slightly to strongly longitudinally grooved, sparsely covered with appressed hairs when young; monocarps 1-10, globose to elliptic with 1(-2) seed, 7.5-15 × 5 mm, 2-seeded ones to 19 mm long, slightly constricted between the seeds, apex apiculate, apex 0.5 mm, rugulose to smooth, glabrous in ripe fruits, ripe fruits bright red. Seeds 5.5-8.0 × 4.5-6.6 mm, globose to ellipsoid, both ends rounded, ochre-brown, raphe not visible, ruminations lamelliform.

Distribution.

From just South of the border of South Africa and Mozambique north to 23 degrees in the province Inhambane in Mozambique. Figure 12 .

Ecology.

Occurring in different types of thickets and forests on sandy soils, at 0-150 m altitude.

Phenology.

Flowers collected in November, December and February to April, fruits collected from March to September.

Conservation status.

Proposed IUCN Red List Category: Least Concern (LC): EOO 43433 km2, AOO 128 km2. Within the distribution range it has been collected from more than 10 different localities and at least 3 nature reserves. Furthermore it is quite common in the coastal dunes of Mozambique, therefore we suggest the status of Least Concern for this species.

Etymology.

Named after the town and province Maputo, the center of the distribution and where most collections originate from.

Additional specimens examined (all paratypes, except when noted as excluded).

MOZAMBIQUE. Gaza: Macia-Messano, 28 Aug 1980, A. Nuvunga 292 (WAG [WAG0065948]); 3 km from Gumbe, 26 May 1965, Â. Pereira 456 (MO [2177512], SRGH; excluded as paratype); between João Belo and Lumane, 6 Mar 1941, A.R. da Torre 2635 (LISC [LISC035251]). Inhambane: Massinga, Pomene, 10 km from Hotel to Rio Das Pedras, 16 Jul 1981, J. de Koning 9063 (LMA, MO [3880770]; excluded as paratype). Maputo: Marracuene, 12 km from Vila Luísa to Manhiça, M.F. Correia 578 (LISC, MO, SRGH); Ilha de Inhaca, 8 Jun 1970, M.F. Correia 1690 (LISC); Lourençco Marques, Ilha da Inhaca, 20 Jun 1973, M.F. Correia 2892 (M, MO); Maputo Reserve, 21 March 1976, M.A. Diniz 102 (MO [2830862], WAG [WAG0053942]); Goba, 23 Feb 1955, A.W. Exell 565 (LISC); Ilha da Inhaca, 19 May 1984, E.M.C. Groenendijk 1377 (MO [3877333], WAG [WAG0053945]); Ilha da Inhaca, 25 June 1984, E.M.C. Groenendijk 1426 (MO [3877334], WAG [WAG0053936]); Ilha da Inhaca, 28 Sep 1984, E.M.C. Groenendijk 1493 (MO [3877332], WAG [WAG0053944]); Ilha da Inhaca, 29 Jul 1985, E.M.C. Groenendijk 1760 (LMU, WAG [WAG0067887], WAG [WAG0067888]); Maputo, 13 Feb 1947, R.M. Hornby 2613 (L [L.1762399], P [P01954698], SRGH); Inhaca Island, 11 Aug 1980, P.C.M. Jansen 7375 (WAG [WAG0053938]); 5 km from Matola-Gare, 13 Feb 1982, P.C.M. Jansen 7808 (BR, G, LMA, WAG [WAG0243995], WAG [WAG0243996]); Rikatla, Nov 1917, H.A. Junod 105 (G [G00308289]); Delagoa Bay, 1890, H.A. Junod 255 (G [G00308287]); Delagoa Bay, 1893, H.A. Junod 522 (G [G00308290]); nearby Bobole, 24 Nov 1978, J. de Koning 7316 (LISC, LMA, MO [3878659]); between Boane and Catuane, 12 Jun 1979, J. de Koning 7379 (K, LMU, MO [3880192], WAG [WAG0375988], WAG [WAG0375989]); 4 km from Catembe, 6 May 1981, J. de Koning 8680 (BR [BR0000013186029], K, LISC, MO [3306014], SRGH); Manhica, 3.5 km from Palmeira, 15 Apr 1975, A. Marques 2725 (WAG [WAG0053940]); Salamanga, 3 Jun 1948, F.A. Mendonça 4480 (MO); Salamanga, 3 Jul 1948, F.A. Mendonça 4493 (EA, WAG [WAG0053946]); Ilha da Inhaca, 3 Jul 1975, A.R. Moura 56 (MA [ MA376952 ], WAG [WAG0053941]); Lourenco Marques, 6 Jun 1946, A. de A. Pimenta 8204 (LISC [2 sheets]); Ilha da Inhaca, 13 Feb 1965, J.E. Rodrigues 329 (WAG [WAG0053934]); Delagoa Bay, 6 Jan 1898, F.R.R. Schlechter 12006 (E [E00624364], G [G00308301], HBG, L [L 0188015], L [L 0188016], L [L 0188017], MO [3726269], P [P01954701], PH [PH00021144], US [553351]); Ilha da Inhaca, 6 Aug 1984, D. Zunguze 781 (WAG [WAG0071706]). SOUTH AFRICA. Kwazulu-Natal: Ndumu Game Reserve, 16 Feb 1969, E.S. Pooley 387 (E [E00624367], PRE); Usuthu Forest, 27 March 1969, 27 Mar 1969, E.S. Pooley 450 (E [E00624366], NU, PRE); Ndumu to Maputa km 23, 7 Mar 1973, F. White 10469 (FHO [00004050]); Tembe Elephant Park, 18 Nov 2000, P.C. Zietsman 4264 (MO [5837895], NY [00642339]).

Discussion.

Most specimens of Monanthotaxis maputensis can be readily distinguished from the similar Monanthotaxis caffra , based on the vegetative and fruiting characters (table 4). These characters overlap in areas where the species occur in close vicinity. The differences in stamen morphology, however, remains clear, even in these areas. In South Africa, close to the border with Mozambique, Monanthotaxis maputensis is confined to sandy soils at low elevations (<200m), while Monanthotaxis caffra occurs there at higher elevations (>600m). Note however that Monanthotaxis caffra occurs at sea-level too, in South Africa (Figure 12 ). Monanthotaxis caffra and Monanthotaxis maputensis are also similar to Monanthotaxis parvifolia (Oliv.) Verdc., which can be distinguished by the rounded to cuneate leaf base (vs subcordate in Monanthotaxis parvifolia ), the scattered soon glabrescent young branches (vs dense ferruginous pubescence in Monanthotaxis parvifolia ). Other characteristics to distinguish Monanthotaxis maputensis from Monanthotaxis parvifolia are the shorter pedicels and shorter petioles in the former species, and fewer carpels in the latter (10-12 vs 12-17).

Two fruiting specimens in the northern range of the distribution (A. Pereira 456 and J. de Koning 9063) were slightly aberrant. A. Pereira 456 has slightly bigger leaves and thick stipes, while the specimen J. de Koning 9063 is more hairy than other specimens and has erect hairs on the young branches. The specimens K. Balkwill 2999 and A.A. Balsinhas 3187 from Kwazulu-Natal had intermediate characters between Monanthotaxis maputensis and Monanthotaxis caffra and did not contain any stamens to verify the identification.

Figures

Figure 11. Monanthotaxis maputensis P. H. Hoekstra. A drawn from Mendonca 4480 B-J drawn from Exell 565 A Habitus with fruit B Habitus with flowers C Flower bud D Open flower with 2 petals removed E Outer petal F Inner petal G Stamen inside H Stamen lateral I Carpel inside J Carpel lateral. Illustration by E. Winkel.

Figure 12. Distribution map of Monanthotaxis maputensis (red squares) and Monanthotaxis caffra (green circles). Large squares / circles denote flowering material of which the stamens were checked, small squares / circles are fruiting or sterile material or only seen from scans. White squares are aberrant fruiting collections of Monanthotaxis maputensis, question marks are fruiting specimens which have intermediate characters between the two species.