Figure 1: Afrothismia korupensis Sainge & Franke

Afrothismia fungiformis Sainge, Kenfack & Afrothismia pusilla Sainge, Kenfack & Chuyong (in press) Chuyong (in press)

Afrothismia sp.nov. Three new species of Afrothismia discovered during this study.

CASESTUDY: SYSTEMATICS AND ECOLOGY OF THISMIACEAE IN CAMEROON BY SAINGE NSANYI MOSES AN MSC THESIS PRESENTED TO THE DEPARTMENT OF BOTANY AND PHYSIOLOGY, UNIVERSITY OF BUEA, CAMEROON

1.0. INTRODUCTION

The family Thismiaceae Agardh comprises five genera Afrothismia Schltr., Haplothismia Airy Shaw, Oxygyne Schltr., Thismia Griff. and Tiputinia P. E. Berry & C. L. Woodw. (Merckx 2006, Woodward et al., 2007) with close to 63 - 90 species (Vincent et al. 2013, Sainge et al. 2012). The worldwide distribution of this family ranges from lowland rain forest and sub-montane forest of South America, Asia and Africa, with a few species in the temperate forest of Australia, New Zealand, and Japan to the upper mid-western U.S.A., on an evergreen, semi-deciduous and deciduous vegetation type. In tropical Africa, they occur in two genera (Afrothismia Schltr. & Oxygyne Schltr.) with about 20 species with the highest diversity in the forest of Central Africa (Cheek 1996, Franke 2004, 2005, Sainge et al., 2005, 2010 and Sainge et al. 2012). The recent taxonomic Classification of Thismiaceae (Merckx et al. 2006) is as follows: Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Family: Thismiaceae Genera: Afrothismia Schltr., Haplothismia Airy Shaw, Oxygyne Schltr., Thismia Griff. and Tiputinia Berry & Woodward

In tropical Africa, thismiaceae was discovered over a century ago but classified as (Engler, 1905). This family is monocotyledonous, and form part of a heterogeneous group of known as the myco-heterotrophic plants (MHPs) (Leake, 1994) consisting of nine plant families: Petrosaviaceae, Polygalaceae, Ericaceae, (Geosiris), Thismiaceae, Burmanniaceae, Triuridaceae, Gentianaceae and some terrestrial Orchidaceae. MHPs receive all essential nutrients from mycorrhizal fungi, which colonize their roots and/or (Leake, 1994). Their lack of green leaves, and subterranean habits leads to the assumption that they live as a parasite on their associated fungi (Leake, 1994). In studying the Biology of MHPs of Southwest Cameroon, Sainge & Franke discovered five new species of Afrothismia, of which four species have been published (A. saingei Franke (2004), A. foertheriana Franke et al. (2004), A. hydra Sainge & Franke (2005) and A. korupensis Sainge et al. (2005)), but unfortunately no species of Oxygyne was recorded. In Africa, Afrothismia Schltr. comprises about 18 species (Sainge, in prep), and Oxygyne Schltr. with two species but only one published (Cheek in prep.). They are found in an evergreen, semi- deciduous, and deciduous forest at an altitudinal gradient of lowland and sub-montane rainforest, ranging from 100 m to 3000 m asl (Sainge, in prep.). Growing in soil at a depth of up to 20 cm (Sainge in prep) and on rotten leaf liter in the wet season (Leake, 1994, Franke, 2007). Hence, Afrothismia is represented in Cameroon with 12 species (Sainge et al., 2012), Tanzania; two species (Cowley 1988, Cheek 2005), Kenya; one species (Cheek 2003), Uganda; one subspecies (Cowley 1988), Gabon; three species (Dauby & Stévart 2008), and Nigeria; one subspecies. Oxygyne Schltr. represent two species (Maas-Van de Kamer, 1998) occurring in Southwest Cameroon [Oxygyne triandra Schltr. and Oxygyne sp.nov. (Cheek in prep.)] and 3 species in Japan. The main hypothesis of this study was to understand the species composition, ecology, distribution and diversity of Thismiaceae in Cameroon in different habitats, and to formulate new models on how to study this group of plants in other countries. This study will lead to the revision of Thismiaceae in Africa and the Flora of Thismiaceae of Cameroon.

SCOPE OF STUDY This study was a follow up research that started since 2000 based on fieldwork and herbaria search (YA, SCA, MO, B, and WAG) from 2002 – 2007. Extended Fieldwork was carried out from April – September 2011 in three vegetation types: evergreen, semi-deciduous, and deciduous, at an altitudinal range of lowland rain forest, and sub-montane forest. In Korup National Park, Diongo Community forest, Transformation Reef Cameroon (TRC) concession 1081, Forest Management Unit (FMU) 11001 at Bakogo, Mount Kupe forest area (Mbulle and Kupe III), Mount Kala, Mefou National Park, Mt. Mvile, PALISCO, FMU 10041 around Mindourou, Mt. Oku and Mbembe forest reserves. Annual species occurrences and abundance per site were assessed.

Figure 2: World Distribution of Thismiaceae (Adapted from Merckx, 2008b)

2.1. TAXONOMIC HISTORY OF AFRICAN THISMIACEAE Rudolf Schlechter, a German botanist, established the Afrothismia in 1906 based on Afrothismia winkleri (Engl.) Schltr. This species was collected in 1904 by Hurbert Winkler (German missionary) around the village of Muea (nickname „Neu Tegel‟) (Engler, 1905). It was described as Thismia winkleri Engler. Adolf Engler was a German Botanist, and in 1905, Engler and Schlechter both visited Cameroon in separate trips and Schlechter recollected T. winkleri Engl. from Moliwe and another new species from Moliwe and he re-described T.winkleri as Afrothismia winkleri (Engl.) Schltr. and A. pachyantha Schltr. In 1940, Eggeling collected a variety of Afrothismia winkleri var. budongensis Cowley from Uganda. A. insignis Cowley from Tanzania was collected by Polhill & Paulo in 1962, and she cited another species A. winkleri var. winkleri from Cameroon and Nigeria (Cowley; 1988). In 1970, Jean Louis Amiet collected another new species from Mount Kala, 20 km west of Yaounde, in the Centre Region, Cameroon while studying the diversity of butterflies. This species was preserved in alcohol and kept at the National herbarium of Cameroon (YA), till 2006 that it was described as A. amietii Cheek (Cheek, 2006). In 1995, A.J de Winter collected another new species from Nyangong in South Cameroon, which was described from spirit collection as A. gesnerioides Maas (Maas; 2003). In 2002, S. Baer collected the first Afrothismia record for Kenya, which was described as A. baerae Cheek (Cheek; 2003). In 2003, Jannerup while studying the vegetation of the eastern arc mountains of Tanzania collected a new Afrothismia, which was described as A. mhoroana (Cheek & Jannerup; 2005). Between 2000, and 2005; Franke & Sainge while studying the Biology of myco-heterotrophic plants in Southwest Cameroon as part of Franke‟s Ph.D work, came across five new species of Afrothismia; of which four species have been fully described thus: A. foetheriana Franke (Franke, 2004), A. saingei Franke (Franke, 2004), A. hydra Sainge & Franke (Sainge, 2005), and A. korupensis Sainge et al. (Sainge et al.; 2005). One new species is pending description because the alcohol material is in very bad shape. Gilles Dauby (a Belgian Botanist) discovered another new Afrothismia species in Gabon and was described as A. gabonensis Dauby (Dauby et al, 2009). Dauby (2008) reported of an unidentified species of Afrothismia from Gabon that was collected by Gentry (Gentry A. 33279) and A. insignis Cowley still from Gabon that was collected by Wilks (Wilks C. 1179). May their SOULS rest in PEACE (Gentry and Wilks). In 2010 Cheek described another new species of Afrothismia from Zambia as A. zambesiaca Cheek. In 2011 while studying the Systematics and Ecology of Thismiaceae in Cameroon, Sainge collected three new species of Afrothismia (Sainge et al, unpublished). Shortly after my study on thismiaceae in 2012, Vincent Merckx sent me some pictures of Afrothismia from Dauby in Gabon which turnout to be another new species. The genus Oxygyne was also established by Schlechter after his trip to Cameroon in 1905. Besides collecting A. winkleri and A. pachyantha, Schlechter also collected a new genus from Moliwe, Cameroon which he described as Oxygyne triandra Schltr. in 1906. Later in 1992 while studying the vegetation of Mt. Cameroon area, Duncan Thomas and Martin Cheek collected another new species of Oxygyne around Mt. Etinde which is not too far from the type locality of O. triandra Schltr.. Unfortunately this species is still unpublished. This genus is extended to Asia with three species collected from Japan: Oxygyne hyodoi Abe & Akasawa (1989), O. shinzatoi (Hatusima) Abe & Akasawa; 1989, and O. yamashitae Yahara & Tsukaya (Yahara & Tsukaya, 2008).

2.2. DESCRIPTION OF THE PLANT (GENERAL MORPHOLOGY) Habit: Afrothismia is a genus of the myco-heterotrophic herb that occurs in tropical Africa in various habitats: low land rain forest, semi deciduous forest, and sub montane forest ranging from sea level to about 3000 m above sea level, and appears between top soil and rotten leaf litter that hardly grows at a depth above 20 cm into the soil. Their entire height ranges from a few millimeters to 20 cm. The diameter ranges from 0.5 – 3 mm. The stem consists of minute scale like alternate leaves and grooves in some species. At the base of the stem is an underground stem “bulbil rhizomes” in clusters with the roots at the end. In some species, clusters of bulbil rhizomes occur at the axil of leaves along the stem. Some species have solitary stems, while others have branching stems with a conspicuous bract at the base of each flower. All species of this genus are composed of six tepals except Afrothismia hydra Sainge & Franke with some population in Korup National Park observed with seven tepals and others 10 tepals, located at the mouth region, and of various lengths in pairs of dorsal, lateral and ventral positions with basal extensions in some species. Their stamens are six except A. hydra that have 7 and 10 stamens with a club shaped anther that bends towards the stigma facing the perianth tube, filaments epipetalous (short and adnate) to the walls of the perianth-tube. Ovary inferior with numerous ovules, placentation unilocular. Fruit-pyxidium (capsule) with the placenta fixed at the receptacle forming a column that exposes the seeds. Eighteen species occurs in tropical Africa. Habit: Oxygyne is a genus of myco-heterotrophic herb that occurs in tropical Africa (Cameroon) and tropical Asia (Japan) in lowland evergreen forest occurring among rotten leaf litter. Height 1 – 4 cm tall, with stem erect or branching with alternate scale-like leaves, roots 1- 5 stout, radiating from the stem base, bracts 3 or more, involucre, scale-like at base of flowers. Flower 1 – 3 per stem, tepals 6, stamens 3, funnel – shaped, ovary inferior, 1 – locular, placenta column 3; free, fruit cup-shaped, truncate-obovoid, upper surface with persistent style.

2.3. ECOLOGY AND DISTRIBUTION Thismiaceae may be widespread in tropical forest but because little attention is given to them, and their occurrence which is mostly in the rainy season makes them very limited in forest flora, and presently occurring only in Africa with Afrothismia Schltr and Oxygyne Schltr. (Cameroon, Gabon, Nigeria, Kenya, Uganda, Zambia, Malawi, and Tanzania), and Asia (Japan) (Sainge, in prep.). The greatest diversity of Thismiaceae in Africa is found in the forest of Central Africa with Cameroon alone harboring 14 species out of the 20 species in Africa. The greatest world distribution of Thismiaceae occurs in the rain forest and sub-montane forest of South America, and Asia with a few species in the temperate forest of Australia, New Zealand, Japan and the upper mid-western U.S.A with Thismia Griff being the most abundant genus (Merckx 2006, Woodward et al., 2007) In Cameroon, Thismiaceae occur at different ecological regions with the greatest majority occurring naturally in a closed tropical sub-montane forest and is assumed to be a good indicator of a pristine and/or refugia ecosystem. Hence, Thismiaceae unlike most MHPs are highly shade tolerant species mostly growing under canopy trees, heavily shaded understorey trees with less than 1% of light reaching them (Chazdon and Fetcher 1984; Lusk et al. 2006). For plant species associated with Thismiaceae (see Sainge 2012a) Rainfall pattern greatly influences the occurrence and distribution of Thismiaceae as these species were mostly collected six weeks after the first rains (Sainge, 2012a).

3.0. MATERIALS AND METHODS

3.1. STUDY SITES This survey was carried out in Korup National park, Mt. Kupe (Kupe III and Mbulle village), Mbembe forest reserve, Mt. Oku, Transformation Reef Cameroon (TRC); Concession 1086, Forestry Management Unit 11001 Bakogo village, Mefou National Park, PALISCO; Forestry Management Unit 10041; Mindourou, Mt. Mvile, Mt. Kala, and Diongo community forest (Figure 3). At each site, two-hectare plots were established at random. Thus a total of twenty- two hectares (220,000 km2 ) were established during this study in an evergreen and semi- deciduous lowland, and sub-montane forest ranging from 0 m to 3000 m asl.

Figure 3: Exploratory Map of Thismiaceae of Cameroon (Study Sites)

3.1.1. CLIMATE The climate of the study area is that of the Equatorial Guinea type covering the Centre (Mt. Kala, Mefou National Park), East (Mindourou), and South (Mvile) region of Cameroon. Dry season is from June - July, November - March and rainy season from March – June, August – November, with about 1500 – 2000 mm of rainfall (Yerima 2005). This mostly occurs in an evergreen and semi-deciduous forest and woodland savanna with an average temperature of 25 0C (Yerima 2005, Fogwe, 2009). The equatorial Cameroon type covers Southwest (Korup National Park, Bakogo, Mt. Kupe), and Northwest (Mbembe forest reserve, Mt. Oku) region (i.e in the neighborhood of Mount Cameroon, Western, and the Bamenda highlands). The dry season range from November – March, and rainy season from March – November (Fogwe, 2009) with annual rainfall been ≥4500 mm occurring in evergreen lowland rain forest (Thomas et al., 2003, Chuyong et al., 2004,), evergreen submontane, montane forest, woodland savanna and mangrove forest with an annual temperature range of 23 – 26 0C (Fogwe, 2009). Specific annual rainfall reading in our study area is variable with the Mindourou area ranging from 1600 to 1650 mm (Fereke 2004). Bipindi to Lolodorf up to 2000 mm – 2500 mm (Olivry 1986, Waterloo et al. 2000). Korup National Park over 5000 mm (Gartlan 1994, Chuyong et al. 2004), Mount Kupe 4891 mm (Suchel 1972), Mount Oku over 2000 mm (Birdlife International, 2011), Mefou National Park 1100 mm – 2000 mm (Bakoh, 2008), Mbembe Forest Reserve 100 - 2000 mm (sainge et al. 2012). Bakogo, and Diongo Community forest had no data yet. FIELD METHODS Since Thismiaceae unlike most myco-heterotrophic plants (MHPs) flower in the wet season (Jonker, 1938, Franke 2004, Sainge, 2005), field studies were carried out in the rainy season from April – September 2011 following plots and the opportunistic sampling method. Plot selection was based on the different vegetation types (Letouzey 1985, Achoundong 2007). At each site, two one-hectare plots were established, coupled with an opportunistic sampling out of the plots. This was to boost the species list, with the exception of Korup National Park where three hectares were established, and Bakogo where only one hectare was established. Each one-hectare plot is composed of 40 x 250 m. During enumeration (evaluation), sampling was done on a transect 20 m away on both sides and 250 m length. To have an idea of their ecology with woody plants, all woody plants ≥ 10 cm in diameter within each 10 x 10 m quadrat where Thismiaceae were recorded were identified to species and soils collected for nutrient analysis. The geographical position of all recorded Thismiaceae species within the plot geo-referenced using GARMIN, GPSmap 60CSx. The number of species and individuals of Thismiaceae were recorded, and samples of each recorded species collected and stored in both 70 % alcohol and silica gel, high quality pictures of each species were taken using a digital camera (Canon, powerShot SD1400 IS), and top soil samples collected up to a depth of 20 cm where species were found. Species abundance of woody plants where Thismiaceae occurred was also sampled. All collected soil samples were thoroughly air-dried (Plate 16) prior to analysis.

3.4. LABORATORY METHODS Plant samples were studied at the Missouri Botanical Garden laboratory and herbarium, National herbarium of Cameroon (YA) Yaounde, and Southern Cameroon herbarium (SCA) in Limbe. Microscopy was carried out to measure: size, root length, tepal length, shape of perigone tube, and size of flower, size of fruit, Stamen and stigma length. Illustrations and evaluation of diagnostic features of all collected species were carried out at the Missouri Botanical Garden laboratory at St. Louis, USA. The soil samples were sent to the IITA-IRAD soil laboratory at Nkolbisson, Yaounde for analysis. Soils were further air-dried, and ground to pass through a 2 mm sieve. Soil pH in water was determined in a 1:2.5 (w/v) soil: water suspension. Organic C was determined by chromic acid digestion and spectrophotometric analysis (Heanes, 1984). Total N was determined from a wet acid digest (Buondonno et al., 1995) and analyzed by colorimetric analysis (Anderson and Ingram, 1993). Exchangeable Ca, Mg, K, and Fe were extracted using the Mehlich-3 procedure (Mehlich, 1984) and determined by atomic absorption spectrophotometry. Available P was extracted by Bray-1 procedure and analyzed using the molybdate blue procedure described by Murphy and Riley (1962). CEC was determined by ammonium acetate extraction, and quantified colorimetrically. Exchangeable Al was extracted using 1N KCl (Barnhisel & Bertsch, 1982) and analyzed using the pyrocatechol violet method described by Mosquera & Mombiela (1986). CEC, Ca, Mg, K, and Al reported as cmol(+)/kg or me/100g whilst P and Fe reported as ppm or ug/g. Total N and Organic C expressed as %. 3.5. DATA ANALYSIS Microsoft excel window 7 was used to manage data and parameters such as relative density, relative frequency, and Shannon diversity index (H‟) were used to describe species distribution, measure species richness and diversity of species at different vegetation and altitudinal gradient. Linear regressions and a multivariate analysis on the soil data, rainfall, and species abundance per site were carried out using SPSS ver. 19. (SPSS 19.0 for Windows; SPSS Inc, Chicago, USA). This study presents the systematics classification of 2 genera (Afrothismia Schltr., and Oxygyne Schltr.) with 11 species.

RESULTS

4.1. A TAXONOMIC REVISION OF AFROTHISMIA AND OXYGYNE (THISMIACEAE, Tribe; THISMIEAE)

1. Afrothismia Schltr. 1. Afrothismia winkleri (Engl.) Schltr. in Engl., Jahrb. XXXVIII (1906) p. 139; Schltr. in Notizbl. 71 (Bnd. VIII) (1921) p. 44; - Thismia winkleri Engl. in Engl., Jahrb. XXXVIII (1905) p. 89, with fig.; Engl., Pfl. Welt. Afr. II in Engl. – Drude, Veg. d. Erde IX (1908) p. 403 and fig. 283 p. 400. Type: Winkler 225, from Neu-Tegel (Muea), Near Buea, Cameroon, (Holotype B, Seen by T. Franke). 2. Afrothismia pachyantha Schltr. in Engl., Jahrb. XXXVIII (1906) p. 139, Fig. 1; Schlechter in Notizbl.71 (Bnd. VIII) (1921) p. 44; - Thismia pachyantha (Schltr.) Engl., Pfl. Welt. Afr. II (1908) p. 403 and p. 401. Fig. 284. Type: Schlechter 15789 from Cameroon, in herb B. 3. Afrothismia korupensis Sainge & T. Franke, sp. nov. Franke Th. (2007). Willdenowia 35:287 – 291.- ISSN 0511-9618; © 2005 BGBM Berlin-Dahlem Holotypus: Cameroon, South West Region, Ndian Division, Southern Korup National Park, close to Chimpanzee Camp, Korup Forest Dynamic Plot (KFDP), 5°04'04''N, 8°51'21''E, c. 230 m, 9.7. 2002, Sainge M. 991 (Holotypus YA; isotypus B) 4. Afrothismia foertheriana Franke, Sainge & Agerer, sp. nov. Blumea – Vol. 49, No. 2 & 3 (2004) 451 – 456. Type: Cameroon, SW – Region, Ndian Division, Diongo Community Forest, peripheral zone of the Onge Forest Reserve, ca. 8 km NE of Diongo village, ca. 4° 25‟ N / 8° 57‟ E, ca. 220 m, 7.October 2002, Franke, Th. & Sainge M 02/030 (holotype: YA; isotypes: B, WAG). 5. Afrothismia saingei Franke, T. sp. nov. Systematics and Geography of Plants 74: 27-33 (2004). ISSN 1374-7886. © 2004 National Botanic Garden of Belgium. Type: Cameroon; South-West Region; Kupe-maneagunba Division; Western slopes of Mt. Kupe, above Mbulle (small village between Tombel and Nyasoso); 4° 47‟ 56‟‟N, 9° 40‟ 26‟‟ E (GPS reading was received in open field ca. 1km SW of type locality); ca. 970 m a.s.l.; Sainge M. 1053, 7.10.2002 (YA holo-; B, BR iso-). 6. Afrothismia hydra Sainge & Franke, sp.nov. Nordic Journal of Botany, 23: 290-303. Copenhagen. ISSN 0107-055X. Type: Cameroon, South West region, Ndian Division, Southern Korup National Park, close to Chimpanzee camp, ca. 230 m, 21st October, 2001, Sainge M. 910 (Holotype: YA; Isotype: B, K).

7. Afrothismia gesnerioides H. Maas sp.nov. BLUMEA- Vol. 48. No.3, (2003), 475 – 478. Type: A.J. de Winter 91, only spirit collection, 24 April 1996 (Holo: WAG 0075095, Isotype: U). Cameroon, South Region, Nyangong, 2050 m on transect *2/4, riverine forest along stream, marshy spot, alt. 600 m, fl and fr. 8. Afrothismia amietii Cheek. Kew Bulletin (2006) Type: Cameroon. Center Region: Mt. Kala, 20 km west of Yaounde, J.L. Amiet 20346/HNC, 27th April, 1970, only spirit collection (Holotpye: YA), alt: 850 m 9. Afrothismia fungiformis Sainge et al., sp.nov. Type: Cameroon, Southwest Region, Mbulle village midway between Tombel and Nyasoso, about 10 km from Tombel, Mt. Kupe. 7th May, 2011, Sainge Moses, and Atabe Rei. s.n. Holo-70 % alcohol, roots in Buffer solution. Sainge M. 2639 (YA). 04.792110 N and 09.677850 E, altitude 966 m, July 30th, 2011; Sainge M. 2760 10. Afrothismia mvileyi Sainge et al., sp.nov. Typus: Cameroon, South Region, Mvile village, 18 km west of Lolodorf between Lolodorf and Bipindi, Mt. Mvile. 5th July, 2011. Sainge Moses and Nzie Gabriel S.n. Holo-70 % alcohol, roots in Buffer solution. Sainge M. 2739 (YA). 03.225850 N, 10.580660 E, alt. 544 m and 03.234120 N, 10.583750 E, alt. 689 m. 11. Afrothismia pusilla Sainge et al., sp.nov. Typus: Cameroon, Centre Region, Kala village, Mt. Kala about 20 km west of Yaounde. 22nd September, 2011. Sainge Moses, and Victor Nana. s.n. Holo-70 % alcohol, roots in Buffer solution. Sainge M. 2827 (YA). 03.841020 N, 11.350070 E, altitude 860 m. 12. Afrothismia sp

2. Oxygyne Schltr. 1. Oxygyne triandra Schltr. in Engl., Jahrb. XXXVIII (1906) p. 140 and p. 139, fig. 4; Engl., Pfl. Welt Afr. II in Engl.-Drude, Veg. der Erde IX (1908) p. 403 and p. 401, fig. 284; Schltr. in Notizbl. 71 (Bnd. VIII) (1921) p. 45.

Table 1: Documented Species of Thismiaceae in Africa

Species Authority Country Reference Sainge & Franke Cameroon, Nordic Journal of Botany 23: Afrothismia hydra Nigeria 299-303 (2005) Sainge & Franke Cameroon Wildenowia 35: 287- Afrothismia korupensis 291(2005) Afrothismia amietii Cheek Cameroon Kew Bull.61(4): 605 (2007) Afrothismia saingei Franke Cameroon Syst. & Geog. Pl. 74(1):28(27- 33).(2004) Franke, Sainge Cameroon Blumea 49: 451-456 (2004) Afrothismia foertheriana & Agarer Afrothismia gesnerioides Maas Cameroon Blumea 48: 475-478(2003) Afrothismia pachyantha Schltr. Cameroon Bot.Jahrb.Syst.38: 139 (1906) Afrothismia winkleri (Engl.) Schltr. Cameroon Bot.Jahrb.Syst.38: 139 (1906) Afrothismia fungiformis Sainge et al. Cameroon In Press Afrothismia mvileyi Sainge et al. Cameroon In Press Afrothismia pusilla Sainge et al. Cameroon In Press Afrothismia sp Cameroon Afrothismia baerae Cheek Kenya Kew Bull.58:951-955(2004) Dauby et al. Gabon Nordic Journal of Botany Afrothismia gabunensis 25:268-271. 2007 (2008) Afrothismia sp. Gabon Cheek & Tanzania Kew Bull. 60: 593-596. 2005 Afrothismia mboroana Jannerup (2006) Cowley Tanzania Fl. of Trop. E. Africa: 1-9. Afrothismia insignis Burmanniaceae 7 (1988) Afrothismia zambesiaca Cheek Zambia Kew Bulletin (2010) Schltr. Cameroon Engl. Jahrb. XXXVIII. P.140 Oxygyne triandra and 139. (1906) Oxygyne sp.nov. Cameroon

3.1. THREATS ENCOUNTERED BY THISMIACEAE OF CAMEROON Habitat distributions worldwide are presently being degraded at an alarming rate (Foster, 2003). Therefore, there is need to assemble every bit of information on the distribution, habitat, and flora of Thismiaceae before they are completely wiped out. Beside the increasing number of Thismiaceae from three species (Schltr. 1906) to twenty species (Sainge in prep.), Thismiaceae still faces a number of threats as they mostly occur in unclassified forest that are poorly managed. At times even those species that are found in protected areas are given less attention as forest encroachment for agriculture, illegal logging, mineral explorations, occurrence of invasive plant species disrupt the occurrence of these species in Cameroon and worldwide. The major environmental threat is that of the dry season. This study coupled with previous studies (Jonker 1938, Franke 2007) proves that Thismiaceae occurs mostly in the rainy season. Land degradation is a major threat to Thismiaceae as they mostly occur in pristine forest. This is true as the type locality of A. winkleri, A. pachyantha, and Oxygyne triandra are now degraded to a huge palm and banana plantations and these species have never been collected again in these sites for over a century. 3.2. CONCLUSION AND RECOMMENDATIONS Our findings in terms of abundance, species richness and endemism have shown that Cameroon is one of the richest sites for myco-heterotrophic plant in the Central African lowland, semi- deciduous, and submontane rainforest. The diversity and endemism is similar to that of the east African forest (Cowley, 1998; Cheek, 2006, 2010) but with few species. These findings may be subject to further studies on the reproductive biology, phylogeny, pollen, seed and fruit structures and the cytology of this group of plants. Although very few studies have been carried out on the cytology (Franke, 2007), and phenology (Sainge, 2003), our study shows that in tropical Africa, Cameroon is the hotspot of Thismiaceae, hosting about fourteen species out of the twenty species in tropical Africa with close to all the species endemic to Cameroon. This high number of endemism and rarity of species makes all our survey sites of high conservation value. Unfortunately, most of the sites occur in unclassified forest or forest with less conservation concern, where illegal timber exploitation and agricultural encroachment is quite alarming. Hence, the protection and sustainable use of resources from forest where these species occur should be of high priority for conservation decision makers in Cameroon. If these areas: Mt. Kupe (the forest between Nyasoso, Mbulle and Kupe III village), Diongo Community forest (close to Onge - Mokoko forest reserve), Mt. Ngovayang (which stretches from Ngovayang I, Mvile, Bidjouka, Lambi, Bipindi, Bibondi to Melondo), and Mt. Kala in the Centre Region are probably not protected, human disturbances such as illegal logging and agricultural activities may rapidly reduce their biodiversity value, thereby reducing the diversity and occurrences of species of Thismiaceae from these sites in the nearest future. The results presented here will fill some of the gaps in the flora of Cameroon, but more still needs to be done in this poorly known group of plants that do not photosynthesize. Field experiments on reproductive biology with limited knowledge at the moment, the ontogeny and phenology of Thismiaceae in Cameroon are key concerns for further studies. Future research on Thismiaceae will focus on their phylogenetic relationships and interactions with mycorrhizal fungi. Preliminary results show that Afrothismia is a monophyletic group, most closely related to Tacca (Taccaceae) (Merckx et al., 2009). Species of Afrothismia show high specificity towards narrow clades of Glomus Group A fungi (Glomeromycota) (Merckx & Bidartondo, 2008). The major limitations of this work is that fieldwork can be carried out only in rainy season, the difficulty of spotting Thismiaceae in the field, and their anthesis are short. In the laboratory, there is great variation in the measurements between wet 70 % alcohol and the dry specimens.

Acknowledgement This study was supported financially by a grant Project Number 10251742 of the Mohamed bin Zayed SPECIES CONSERVATION FUND 2010, field equipments were received from the IDEAL WILD. Herbarium, Laboratory and travel financial assistance was received from the Center for Tropical Forest Science (CTFS) and the Missouri Botanical Garden (MBG) in the United States.