Cyrtorchis chailluana (Hook.f.) Schlechter (1914: 596)

Azandi, Laura, Stevart, Tariq, Sonké, Bonaventure, Simo-Droissart, Murielle, Avana, Marie-Louise & Droissart, Vincent, 2016, Synoptic revision of the genus Cyrtorchis Schltr. (Angraecinae, Orchidaceae) in Central Africa, with the description of a new species restricted to submontane vegetation, Phytotaxa 267 (3), pp. 165-186 : 176-177

5. Cyrtorchis chailluana (Hook.f.) Schlechter (1914: 596) . ( Fig. 3B ) Basionym: Angraecum chailluanum Hooker (1866 : t.5589). Listrostachys chailluana (Hook.f.) Reichenbach (1885: 381) . Angorchis chailluana (Hook.f.) Kuntze (1891: 651) . Types:— NIGERIA. Banks of the Nun River, September 1860, G.Mann 521 (syntype K!). GABON. Sine loc., P.B. du Chaillu s. n. (syntype K)

Additional specimens examined:— SIERRA LEONE. Nyadehun, Kenema district , 5 September 1982, Segerbäck 1549 (K) . NIGERIA. Calabar government Station , September 1948, Kaey 13348 (K) ; Benin , Okomu F. R., December 1947, Brenau & Kaey 25438 (K) ; Bonny , 15 December 1957, Stubbings 49 (K) ; Lagos, January 1896, Millen 193 (K) ; Old Calabar , 20 August 1898, Holland 135 (K) ; Sapoba , s. d., Kennedy 1913 (K) . CAMEROON. Douala, Edea forest , 27 June 1978, Thomas 204 (K) ; Lobéké river close to confluence with the sangha, 350 m, 15 September 1988, Harris & Fay 1120 (K) ; Akoakas rock, about 24 km, on the old road from N’Koemvone to Ambam , 660 m, 19 November 1975, de Wilde 80 ( YA) ; Ngoyla, campement à 13 km à l’Est du village, cacaoyère, 484 m, 25 July 2012, Droissart et al. ( Ombrière de Yaoundé ) 3688 ( BRLU, YA) ; ibid., 24 September 2010, Simo et al. ( Ombrière de Yaoundé ) 2415 ( BRLU, YA) ; Nguti, Exploitation forestière, Village d’Edjuigang , 155 m, 13 August 2006, Droissart et al. ( Ombrière de Yaoundé ) 408 ( BRLU) ; ibid., 23 August 2006, Droissart et al. ( Ombrière de Yaoundé ) 414 ( BRLU) ; ibid., 8 August 2007, Droissart et al. ( Ombrière de Yaoundé ) 637 ( BRLU, YA) ; 12 September 2005, Droissart et al. ( Ombrière de Yaoundé ) 316 ( BRLU) ; Mbouma, plantation de cacao, 662 m, 7 September 2007, Droissart et al. ( Ombrière de Yaoundé ) 706 ( BRLU) ; ibid., 20 September 2004, Droissart et al. ( Ombrière de Yaoundé ) 120 ( BRLU) ; ibid., 647 m, 15 September 2001, Stévart & Pial 223 ( BRLU) ; Akom II (route Kribi-Ebolowa), campement à 3 h de marche au S du village, le long de la rivière à environ 60 m du campement, 710 m, 27 September 2007, Droissart et al. ( Ombrière de Yaoundé ) 757 ( BRLU) ; ibid., 12 October 2008, Simo et al. ( Ombrière de Yaoundé ) 1386 ( BRLU) ; ibid., relevé permanent (1 ha) sur plateau situé au N-NE du campement., 785 m, 19 October 2008, Simo et al. ( Ombrière de Yaoundé ) 1399 ( BRLU) ; ibid., 20 October 2009, Simo et al. ( Ombrière de Yaoundé ) 1890 ( YA) ; Mbam-Minkom (région au Nord-Ouest de Yaoundé), relevé effectué au sud-ouest du village de Kolaki, 500 m, 18 July 2005, Droissart et al. ( Ombrière de Yaoundé ) 309 ( BRLU) ; ibid., village de Nye-Meyong, le long de la route entre Nyemeyong et Ekekam, 815 m, 19 October 2010, Simo et al. ( Ombrière de Yaoundé ) 2488 ( BRLU, YA) ; Victoria Botanic Garden , 3 September 1946, Ngongi 15082 (K) ; Mont Kupé, Nyasoso , 850 m, 3 August 1992, Cable 33 (K) ; S.N. Ekema E3, 14 October 1971, SCA 2365 ( YA) ; Site en cours d’exploitation dans l’UFA 09-003 à 55 km au Sud-Est de Djoum, 611 m, 27 July 2011, Simo et al. ( Ombrière de Yaoundé ) 2966 (K, YA) ; ibid., 15 February 2012, Simo et al. ( Ombrière de Yaoundé ) 3424 ( BRLU, P) ; Mont Cameroun, route entre Debunscha et Idenau, 5 m, 2 February 2012, Simo et al. ( Ombrière de Yaoundé ) 3414 ( BRLU) ; Mindourou site d’exploitation de la Pallisco près de Lomié (AC 5), 770 m, 1 September 2001, Stévart & Pial 202 ( BRLU) ; ibid., 1 October 2001, Stévart & Pial 23 0 ( BRLU) ; AC UFA 09006 Fanga -Mbouma , 684 m, 18 August 2003, Stévart & Pial 871 ( BRLU) ; Colline de Nkoltsia , 22 March 1974, Villiers 808 ( P, YA) ; Monastère de Koutaba, entre Bafoussam et Foumban, 1,164 m, 9 June 2014, Droissart et al. ( Ombrière de Yaoundé ) 5130 ( BRLU) ; village de Ma’an, UFA 09-022 (Wijma), 549 m, 4 November 2014, Droissart et al. ( Ombrière de Yaoundé ) 5733 ( BRLU) ; Nyombi, 1953, Merle s. n. ( P) ; Djaposten , 30 km NNW Lomié, 23 August 1972, Letouzey 11666 ( P, YA) . CENTRAL AFRICAN REPUBLIC. Dzanga Sangha reserve, Ndakan gorilla study area from Ndakan camp to Nyangouté on the East bank of the Sangha river , 350 m, 9 August 1988, Harris & Fay 951 (K) . EQUATORIAL GUINEA (RIO MUNI). Mongum (inselberg), 17 September 1999, Ndong Bokung & Stévart 66 ( BRLU) ; Akonangui (route de Monte Alén à Niefang , avant entre Ayene et Bikaba), 550 m, 15 November 1999, Ndong Bokung & Stévart 119 ( BRLU) ; Piedra Nzas (inselberg de), à 6h de marche du village d’Acoaseng , à 9 km d’Aconibe, ou de celui de Afaanam, 630 à 745 m, 31 August 2002, Ndong Bokung & Stévart 504 ( BRLU) . GABON. Haute-Ngounyé, Sindora , 24 March 1926, Le Testu 5870 ( BR, P) ; Noumbo Yogoulou , 22 November 1925, Le Testu 5780 ( BR, P) ; Sine loc., 70 m, May 1896, Bates 462 (K) ; bords de la Ngounyé Sandara, 28 January 1918, Le Testu 2258 ( P) ; Cap Lopez, 1913, Pobéguin s. n. ( P) ; ibid., 20 February 1894, Dybowski 138 ( P) ; Rivière Maliba , 11 June 1969, Villiers 131 ( P) ; About 17 km along the road Libreville to Cape Estérias , 30 m, 25 November 1983, de Wilde et al. 761 ( BR, P) ; About 8 km N of Mayumba, 5 m, 6 December 1986, de Wilde et al. 9186 (K) ; Kembouya , 18 September 1932, Le Testu 8904 ( BR) ; C. E. F. A. Ayem, 10 Km SW de Ndjole, 16 April 1963, Hallé 1684 ( P) ; Cap Esterias , s. d., Hallé & Villiers 5457 ( P) ; Tchimbélé , près du bras mort du lac, 570 m, 24 February 2002, Stévart 1687 ( BRLU) ; ibid., 24 February 2002, Stévart et al. 1636 ( BRLU) ; Environs de Libreville , 6 December 1899, Klaine 1648 ( P) ; ibid., 28 February 1901, Klaine 437 ( P) ; Sine loc., February 1896, Klaine 1 2 ( P) ; Ad flumen Ndreme , May 1899, Trilles 2 ( P) ; Ste Anne du Fernan-Vaz ( Odimba ), s. d., Walker 34 ( P) ; Libange farm, 8 March 1881, s. coll. 281 (K) . REPUBLIC OF THE CONGO. Sine loc., s. d., Mocquerys s. n. ( P) ; Région de Pointe-noire, Pointe-Indienne , 1 June 1966, Sita 1234 ( P) . DEMOCRATIC REPUBLIC OF THE CONGO. Aruwimi , 3 April 1905, Lacomblez 50 (K) ; Sabuka , 18 February 1909, Laurent 536 ( BR, BRLU) ; Yangambi, île Yalututcha en face du poste, 470 m, 20 August 1938, Louis 10948 ( BR) ; ibid., île Esali en face du poste, 470 m, 20 August 1938, Louis 10950 ( BR) ; Kisangani , 20 August 1981, Ndjele 539 ( BR) ; Monsole , 17 August 1908, Seret 913 ( BR) ; s. d., Solheid 118 ( BR) . UGANDA. Bushenyi district, S. Kasyoha- Kitomi forest, Nzozi , 1,330 m, June 1998, Hafashaimana 623 (K) ; N.W. side of lake Nabugabo , 1,140 m, 9 October 1953, Drummond & Hemsley 4724 ( BR, K) ; Lele Kabugabo , 1,181 m, July 1937, Glhandler 1982 (K) ; Bale, lake Nabugabo , 1,140 m, 5 May 1969, Lye 2782 (K) ; Bugala Island , 1,137 m, 24 February 1945, Greenway & Thomas 7163 (K) ; Bushenyi, Karinzy , May 1995, Spurrier U 46 (K) ; Lake Nabugabo , 1,067 m, May 1934, Geak 6014 (K) ; Kampala Entebbe Road , 1187 m, December 1902, s. coll. s. n. (K) ; Bwaan , 6 March 1891, Glasnevin s. n. (K) ; Burford lodge, October 1889, Lawrence s. n. (K) .

Additional specimens examined with unspecified country: —sine loc., July 1858, s. coll.s. n. (K).

Distribution:— According to Govaerts et al. (2016), Cyrtorchis chailluana occurs in fifteen countries ( Guinea, Sierra Leone, Liberia, Ivory Coast, Togo, Nigeria, Cameroon, Central African Republic, Republic of the Congo, Equatorial Guinea, Gabon, Democratic Republic of the Congo, Burundi, Rwanda, and Uganda), although we have not examined any material from Guinea, Liberia, Ivory Coast, Togo, Burundi and Rwanda. Cyrtorchis chailluana is thus widely distributed in Sub-Saharan Africa.

Habitat and ecology:— Epiphyte in dense forest between 30 and 1,330 m elevation. Flowering peaks in August and September.

Notes:— This species has the longest spur of all Cyrtorchis species, up to 16 cm long. We didn’t choose a lectotype among the two syntypes cited above since we were not able to find the syntype du Chaillu s. n. in the Kew herbarium.

Figures

FIGURE 3. Illustrative pictures of some central African taxa of the genus Cyrtorchis. A. C. arcuata. B. C. arcuata subsp. whytei. C. C. aschersonii. D. C. brownii. E. C. chailluana. F. C. hamata. G. C. henriquesiana. H. C. injoloensis. I. C. letouzeyi. J. C. monteiroae. K. C. ringens. L. C. submontana. Photographs ‘A–G’ & ‘I–L’ by Droissart Vincent and ‘H’ by Lourens Grobler.