Xylopia collina Diels, Notizbl. Bot. Gart. Berlin-Dahlem 13: 271-272. 1936.

Johnson, David M. & Murray, Nancy A., 2018, A revision of Xylopia L. (Annonaceae): the species of Tropical Africa, PhytoKeys 97, pp. 1-252 : 87-89

13. Xylopia collina Diels, Notizbl. Bot. Gart. Berlin-Dahlem 13: 271-272. 1936. Figs 3I , 4E , 21A, C, F, H, I, J

Xylopia latipetala Verdcourt, Kew Bull. 25(1): 12. 1971. Type. TANZANIA. Lindi District: Rondo Plateau, Nahoro in Albizia , Chlorophora woodland, on old termite-hill, 11 Dec 1955 (fl), Milne-Redhead & Taylor 7617 (holotype: K-2 sheets!).

Type.

TANZANIA. Lindi Region, 40 km westlich von Lindi, Lutambasee [ “Lumbatasee”], 14 Oct 1934, H.-J. E. Schlieben 5470 (lectotype, here designated: B! [10 0153136]; isotypes: B! [100153137, 100153138, 100153139], BM! [000511056], BR! [0000008824783], G! [00190716], HBG [502482, 502483, 502484], K! LISC! [000402], M! [0107918], MA! [385126], MO! [1703951], P! [00363256], PRE! [0397107-0], S! [07-13459], US! [2214646]).

Description.

Shrub or small tree up to 4 m tall, d.b.h. up to 4 cm, twigs often somewhat flexuous on new growth. Twigs brown to reddish brown, densely erect-pubescent, the hairs 1-2 mm long, becoming gray-brown, glabrate or with the hairs somewhat persistent, bark developing minute exfoliations on the leafless growth; nodes occasionally with two axillary branches. Leaf with larger blades 4-8.4 cm long, 2.1-4.4 cm wide, chartaceous, concolorous or slightly discolorous, elliptic to ovate, occasionally lanceolate or obovate, apex acute to rounded, base subcordate or rounded, uniformly pubescent with hairs persistent on both surfaces and on the margin, slightly denser on the midrib; midrib plane to slightly raised adaxially, slightly raised abaxially, secondary veins indistinctly brochidodromous, 6-13 per side, diverging at 35-70° from the midrib, these and higher-order veins slightly raised on both surfaces; petiole 2-4 mm long, shallowly canaliculate, pubescent. Inflorescences axillary, 1-flowered, pubescent; pedicels not pedunculate, 1-3 mm long, 0.6-1.5 mm thick; bracts 2, evenly spaced along pedicel, caducous or rarely persistent, 1-2.7 mm long, semicircular or crescent-shaped, apex obtuse; buds lanceolate to ovoid, apex acute. Sepals erect to slightly spreading at anthesis, 1/5-1/2-connate, 2.5-4.1 mm long, 2.5-3 (-4.8) mm wide, coriaceous, ovate, apex acute, pubescent abaxially. Petals dull red to grayish pink in vivo; outer petals erect at anthesis, 9-20.4 mm long, 2.5-8 mm wide, 1.4-3.9 mm wide at midpoint, coriaceous to fleshy, linear-lanceolate to lanceolate, apex acute, densely puberulent on both surfaces except for a glabrous patch at base adaxially; inner petals geniculate at anthesis, with the apices bent sharply outward between the outer petals, 6-15.4 mm long, 2-5.2 mm wide, wide, 0.4-2.3 mm wide at midpoint, coriaceous to fleshy, lanceolate-acuminate, apex acute, base with undifferentiated margin, transversely thickened at the widest point adaxially, bearing a band of corrugated tissue just above the claw, puberulent except for glabrous base adaxially, puberulent on narrow apical portion and medial region of base but otherwise glabrous abaxially. Stamens 120-200; fertile stamens 0.8-1.4 mm long, narrowly oblong to clavate, apex of connective 0.1-0.3 mm long, shieldlike or slightly hemispheric, overhanging the anther thecae, papillate, anthers 10-17-locellate, filament 0.3-0.4 mm long; outer staminodes 1.0-1.3 mm long, clavate, apex truncate, sometimes oblique; inner staminodes 0.8-0.9 mm long, clavate to oblong, apex rounded to truncate; staminal cone 1.7-2.8 mm in diameter, 1.0-1.7 mm high, concealing only the bases of the ovaries, rim laciniate. Carpels 3-7; ovaries ca. 1 mm long, oblong, sericeous, stigmas connivent, ca. 1.3 mm long, lanceolate to trowel-shaped, bearing a tuft of hairs at the apex. Torus flat, 2.5-3.2 mm in diameter. Fruit of up to 6 glabrate monocarps borne on a pedicel 3-7 mm long, 1.2-2 mm thick, pubescent, with sepals persistent; torus 2.5-4 mm in diameter, 2.0-2.2 mm high, globose to depressed-globose. Monocarps with yellowish or glaucous green exterior and scarlet endocarp in vivo, 1.3-3.6 cm long, 0.6-1.3 cm wide, (0.5-) 0.7-1.2 cm thick, oblong, irregularly torulose, apex obtuse to acute, rarely mucronate, contracted into a stipe 3-10 mm long, 1.7-2.2 mm thick, surface pruinose, longitudinally wrinkled and finely verrucose; pericarp ca. 0.5 mm thick. Seeds up to 7 per monocarp, in two irregular rows, lying oblique to long axis, 9.8-12.2 mm long, 5.5-7.4 mm wide, 4.5-7.0 mm thick, pyriform, narrowed into a cylindrical neck 1.6-2.3 mm long and 2.7-3.5 mm wide toward micropyle, irregularly ellipsoid in cross section, obliquely truncate at micropylar end, rounded at chalazal end, brown, smooth, shiny, raphe/antiraphe not evident, micropylar scar 1.4-1.5 mm long, 1.0-1.1 mm wide, elliptic; sarcotesta bright orange, fleshy in vivo; aril absent.

Phenology.

Specimens with flowers have been collected in February, March, October, and December, and with fruits in June and from November to March.

Distribution

(Fig. 22 ). Restricted to southeastern Tanzania and northeastern Mozambique, where it grows in thickets and open woodland on slopes and plateau surfaces, usu ally on deep white sand and less commonly on loam, often locally common on roadsides and in areas mixed with planted cashew ( Anacardium ) trees, at elevations of 200-900 m.

Local names.

Mutuka (Kimakonde, Busse 2858), nampemedi (Kiswahili, Johnson & Swedi 1914), pempantavala (Kimuera, Schlieben 5470; the same common name was reported by Schlieben as being used for Popowia (now Monanthotaxis ) trichantha, see Diels 1936).

Additional specimens examined.

TANZANIA. Lindi: Rondo Plateau, Rondo Forest Reserve, below Forest Station , 10°07'S, 39°14'E, 13 Feb 1991 (fl), Bidgood et al. 1535 (DSM, EA, K, NHT), 13 Feb 1991 (fr), Bidgood et al. 1544 (EA, K-2 sheets, MO, NHT) ; track from Nyengedi to Rondo Plateau , 10°12'S, 39°20'E, 16 Feb 1991 (fl), Bidgood et al. 1600 (DSM, EA, K, NHT) ; [" Nordwestliches Muera-Plateau, etwa 600 m ü. M., in dichter Buschenklave auf sandigen Boden ", 14 Jun 1903 (fr), ex Diels 1936], Busse 2858 (EA) ; Mchinjiri, Rondo Plateau , Nov 1951 (buds), Eggeling 6386 (K, TFD) ; track from Nyengedi (between Masasi and Mnazimoja ) to Rondo Plateau , ca. 3 km N of Nyengedi, 10°14'00"S, 39°24'00"E, 7 Mar 1996 (fl, fr), Johnson & Swedi 1906, 8 Mar 1996 (fl, fr), Johnson & Swedi 1910 (DSM, OWU) ; Lindi District, Nyangamara Forest Reserve , 10°19'S, 39°59'E, 10 Mar 1996 (fl, fr), Johnson & Swedi 1914 (DSM, OWU) ; Noto Plateau , N of Chitoa Plateau, 09°54'S, 39°24'E, 8 Jul 2008 (buds), Mwangoka et al. 5801 (OWU) ; Lindi District, Rondo Forest Reserve , 21 Jan 1968 (fr), Shabani 43 (EA, TFD) ; Lindi Rural District, Mtama Division, Namiupa Ward , Rondo Forest Reserve , NW of Mihima Village, 10°12'19"S, 39°09'21"E, 640 m, 3 Nov 2005 (fr), Simon Laizer et al. 1352 (OWU) .- Mtwara: Newala District, Mahuta , 16 Dec 1942 (buds), Gillman 1055 (EA, K) ; Mnima , 23 Mar 1943 (fr), Gillman 1293 (K) ; Newala District, road from Mtama to Mkwiti , ca. 2 km N of Mkwiti, 10°03'S, 40°11'E, 10 Mar 1996 (fl, fr), Johnson & Swedi 1913 (DSM, OWU) . MOZAMBIQUE. Cabo Delgado: Palma area, on old western road to Quionga , 10.8 km from the roundabout at the white church, 10°40'49"S, 40°26'11"E, 60 m, 12 Mar 2008 (fl buds), Burrows & Burrows 10942 (K) ; Palma area, 1 km E of Muangaza S of Palma , 10°55'25.5"S, 40°23'34.8"E, 65 m, 5 Dec 2008 (fr), Goyder et al. 5084 (K) ; Nanhamba , 7 km S of Mocimboa do Rovuma, 11°19'27"S, 39°18'55"E, 573 m, 10 Sep 2009 (fr), Lötter & Turpin 1882 (K) ; Mueda Plateau , 11°24'S, 39°23'E, 860 m, 12 Dec 2003 (yg fr), Luke et al. 10039 (K, MO) ; Niassa, Chomba, entre o cruzamento e Chomba , 20 Sep 1948 (st), Pedro & Pedrogão 5279 (EA) ; Palma District, Miculumo area , 10 km NW of Palma, 10°40'39.9"S, 40°25'08.9"E, 56 m, 6 Dec 2008 (fl), Timberlake et al. 5640 (K) .

The red flowers of Xylopia collina are unusual in the genus and, coupled with the shrub habit, the long erect hairs on the twigs and leaves, and the pruinose surface of the dried monocarps, make it a distinctive and easily recognized plant. With the examination of more extensive material, we do not maintain Xylopia latipetala Verdc. as a distinct species. The type specimen, Milne-Redhead and Taylor 7617, does indeed bear flowers with sepals and petals broader than in the type specimen of X. collina , but the gap in sizes presented in Verdcourt’s (1971a) description has now been filled by additional specimens: Bidgood et al. 1535, for example, has flowers with the outer petals 4.9-6.9 mm wide, i.e. intermediate in size between the two described species. We also observed considerable variation in petal size and shape within field populations of X. collina , suggesting that variation in petal size is a normal attribute of this species.

Although the flowers emit an ester/vinegar scent of rotting fruit during the middle of the day, suggesting small flies, nitidulid beetles, or thrips as possible flower visitors, no pollinators were found. Color cues may be important in determining the timing of pollinator behavior, as the flower buds are initially white, then become pink or pinkish orange, and finally turn pinkish red. The tips of the petals often become black or dark gray. A band of corrugated tissue crosses the adaxial surface of the inner petal at its widest extent and may provide a food reward for pollinators. As in X. arenaria , onset of anthesis is signalled by the bending of the apices of the inner petals so that they emerge through the gaps between the erect outer petals.

Associates observed at several sites included Bosqueiopsis gilletii , Milicia excelsa , Grewia conocarpa , and species of Albizia , Heinsia , Hymenocardia , Indigofera , Mimosa , and Pteleopsis . In the area of a recent burn on the Rondo Plateau in March, 1996, Xylopia collina was one of several Annonaceae , including also Dielsiothamnus divaricatus , Monanthotaxis buchananii , Monodora minor , and Uvaria acuminata , observed to be regenerating from a rootstock after fire. The indurated black bud scales on the vegetative buds may play a role in allowing shoot regeneration after fire or drought; such bud scales are unusual in Annonaceae , where dormant shoot tips are typically naked. The growth of X. collina also exhibits distinctive stem galls (Fig. 20F ) that are seen in other African species of Xylopia .

There are four sheets of the type collection, Schlieben 5470, at B. None is in exact agreement with the protologue concerning the type locality, but the sheet with detail drawings of the floral parts attached is chosen as the lectotype.

As shown in Table 1 , the AOO for this species was relatively high (76 km 2) for the size of its EOO (12,374 km 2). We found X. collina to be locally frequent along roadsides, which may make it more frequently collected. In the IUCN Red List (version 3.1), it has been classified, however, as Endangered, largely due to the small size of its global distribution and local habitat alteration.

A decoction of the leaves of Xylopia collina was reported by local informants in the Nyangamara region of southern Tanzania to be used as a treatment for hernia.

Figures

Figure 3. Flowers of representative Xylopia species. A Flower from type collection of Xylopia globosa from Gabon B Xylopia tenuipetala from Mozambique C Xylopia quintasii from Gabon D Xylopia aethiopica from Gabon E Xylopia longipetala from Mali, representing a record for the country not otherwise documented F Xylopia piratae from Ivory Coast G Xylopia odoratissima from Zambia H Xylopia arenaria from Tanzania I Xylopia collina from Tanzania. A, D by Thomas L. P. Couvreur B by Frances Chase C by Ehoarn Bidault E by Philip Birnbaum F by Celine Pirat G by Warren McClelland H and I by D. M. Johnson.

Figure 4. Fruits and seeds of representative Xylopia species. A Xylopia staudtii from Democratic Republic of the Congo B Xylopia aethiopica from Republic of the Congo C Xylopia quintasii from Cameroon D Xylopia tenuipetala from Mozambique E Xylopia collina from Mozambique F Xylopia gracilipes from Mozambique G Xylopia hypolampra from Gabon H Xylopia tanganyikensis from Tanzania. A by Quentin Luke B by David Harris C, G by Thomas L. P. Couvreur D by Jonathan Timberlake E, F by Mervyn Loetter H by Noriko Itoh. C reproduced with permission of Thomas L. P. Couvreur and of the American Society of Plant Taxonomists D reproduced with the permission of Jonathan Timberlake and of the Board of Trustees, Royal Botanic Gardens Kew.

Figure 20. Xylopia tenuipetala. A Leaf B Habit C Fruit, showing one dehisced and one undehisced monocarp D Seed, view of micropylar end E Seed, side view F Carpel, with ovary dissected to show two ovules G Stamen, abaxial view H Flower I Inner petal, adaxial view J Outer petal, adaxial view. A, F-J from Goyder et al. 6090 (K) B from photograph of same in vivo C-E from Goyder et al. 5089 (K). Reproduced with the permission of the Board of Trustees, Royal Botanic Gardens Kew.

Figure 21. Xylopia collina and X. arenaria. A, C, F, H, I, J X. collina. A Monocarp, lateral view C Flower, lateral view F Stem gall H Habit I Bud J Torus with attached ovaries, lateral view B, D, E, G X. arenaria B Fruit D Habit E Flower bud with one outer petal removed, lateral view G Bud. A, F, H from Johnson et al. 1914 (OWU) B from Johnson & Murray 1890 (OWU) C, I, J from Johnson et al. 1913 (OWU) D, E, G from Johnson et al. 1937 (OWU).

Figure 22. Distributions of Xylopia arenaria, X. collina, X. tomentosa, and X. keniensis in southern and eastern Africa. Bolder lines represent country borders, fainter lines lakes and major rivers.