[Sect.Daphnanthes Subsect.Gnidium] from Northern África:D. Mauritanica
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A NEGLECTED DAPHNE [SECT. DAPHNANTHES SUBSECT. GNIDIUM] FROM NORTHERN ÁFRICA: D. MAURITANICA, SP. NOV. (THYMELAEACEAE)* by GONZALO NIETO FELINER** Resumen NETO FEUNER, G. (1995). Una especie olvidada de Daphne [sect. Daphnanthes subsect. Gni- dium] del norte de África: D. mauritanica, sp. nov. (Thymelaeaceae). Anales Jard. Bot. Madrid 53(2): 191-197 (en inglés). Se describe una nueva especie de Daphne [sect. Daphnanthes subsect. Gnidium] de las mon- tañas del norte de África: D. mauritanica. La nueva especie, que se había confundido con D. gnidium o se había reconocido como una mera variedad -lanata- de aquélla, se diferencia por varios caracteres morfológicos y anatómicos, entre los que destacan la persistencia del hi- panto, la glabrescencia de los tallos del año, el indumento de los órganos reproductivos y la dis- posición de los estomas. En este artículo se comentan, e ilustran -con M.E.B.-, estos caracte- res y se ofrece un mapa de distribución de ambas especies en el norte de África. Palabras clave: Thymelaeaceae, Daphne subsect. Gnidium, taxonomía, norte de África. Abstract NIETO FEUNER, G. (1995). A neglected Daphne [sect. Daphnanthes subsect. Gnidium] from Northern África: D. mauritanica, sp. nov. (Thymelaeaceae). Anales Jard. Bot. Madrid 53(2): 191-197. A new species oí Daphne [sect. Daphnanthes subsect. Gnidium] from Northern África is des- cribed: D. mauritanica. This taxon has often been misidentified as D. gnidium or subordinated to it as a mere variety -lanata-. It differs from D. gnidium in various relevant morphological and anatómica! characters such as persistenthypanthium, glabrous shoots, indument ofrepro- ductive organs and arrangement of the stomata, among others. All the differences detected are commented upon and illustrated with S.E.M. micrographs. A map with the distribution of both species in Northern África is also provided. Key words: Thymelaeaceae, Daphne subsect. Gnidium, taxonomy, Northern África. iNTRODUcnoN 1898; BRICKELL & MATHEW, 1976). A poorly known species described from cultivated ma- Daphne [sect. Daphnanthes C. A. Meyer] terial apparently of Chinese origin (in the Cal- subsect. Gnidium (Spach) Keissler is known cutta Botanic Garden), D. roumea Meisn., to include a single, taxonomically well esta- was placed by the first two authors in subsect. blished species -D. gnidium L.- distributed in Gnidium. However, both its taxonomic status southern Europe, northern África and the Ca- as well as its placement are unclear and will nary Islands (MEISNER, 1857; KEISSLER, notbe treated here. * This work has been supported in part by the Dirección General de Investigación Científica y Técnica (DGICYT) through the project "Flora iberica" (PS91-0070-C03-01). ** Real Jardín Botánico, CSIC. Plaza de Murillo, 2. E-28014 Madrid. 192 ANALES JARDÍN BOTÁNICO DE MADRID, 53(2) 1995 In preparing an account of the genus for RESULTS Flora iberica, I have had the opportunity to study a considerable amount of North African Daphne mauritanica Nieto Feliner, sp. nov. material. Among the material identified and D. gnidium var. lanata Faure & Maire in Mai- referred to as D. gnidium from that continent, re, Bull. Soc. Hist. Nat. Afrique N. 22: 314 I have been able to recognize two species. (1931) One is D. gnidium, s.str., common in southern D. gnidium sensu Batt. & Trabut, Fl. Algérie Europe and the other is described in the pre- 1: 783 (1890); sensu Quezel & Santa, sent paper. Two infraspecific ñames have so- Nouv. Fl. Algérie 2:631 (1963), non L. metimes been applied to the latter, but the ta- Speciei Daphne gnidium affinis, a qua xonomic significance of the characters dis- praecipue differt caulibus annotinis glabris, tinguishing the new entity, together with its inflorescentia palam exserta coopertaque large distribution área, clearly make infraspe- -hypanthiis pedicellisque non exceptis- pilis cific ranks inappropriate. potius longis (0.3-0.6 mm), densis atque val- When KEISSLER (1898: 72) described his de applicatis, foliis insuper subtus glaucis nec D. gnidium f. latifolia he cited several Euro- manifesté punctatis cum stomata superficialia pean specimens in addition to one from Tuni- sint nec in cavis imis veniant — ut in D. gni- sia, the latter actually belonging to the new dium accidit — , bracteis pubescentibus, de- species. Such a form lacks any taxonomic sig- munque atque singulariter hypanthiis per- nificance. sistentibus latisque (fructiferis, plerumque The Algerian type material of the second 3.7 mm latís). infraspecific taxon -D. gnidium var. lanata Habitat in montosis Africae borealis, ab Faure & Maire (in MAIRE, 1931, 1937; JA- alto Atlante usque in Regnum Tunetanum. HANDIEZ & MAIRE, 1931,1934)-fully corres- ponds with the new species. This variety was Typus: Algérie, environs de Tlemcen, diagnosed exclusively by the longer wooly broussailles, bords de chemins, 900 m, 18- hairs on the inflorescence. The failure to de- VI-1933, A. Faure. Holotypus: MA 83302 tect other important distinguishing characters (fig. l);Isotypus:G. probably explains the low rank attributed to Distribution: The new species is distribu- this taxon which, after a detailed study, I pro- ted along a narrow but long (c. 2000 km) lon- pose to accord specific status. gitudinal range, from the Western High Atlas near Marrakesh to the Zaghouan Mountain in Tunisia (fig. 2). It occurs at more continental MATERIAL AND METHODS sites and at higher elevations (700-2500 m) than D. gnidium. In North África, the latter Specimens from the following herbaria species is apparently restricted to an even na- have been examined: BCF, G, GDAC, rrower belt almost as long as that of D. mauri- JACA, MA, MAF, MGC, SALA. For the epi- tanica along the Mediterranean coast. dermal study, fresh specimens were fixed in a mixture of 50% ethanol, 40% distilled water, DISCUSSION 5% formaldehyde and 5% glycerol; desicca- ted specimens were rehydrated in ethanol Hypanthium .-Despite the opinión expres- (70%). The epidermis was peeled-off with a sed by KEISSLER (1898: 73, footnote) when razor for observation with light microscopy discussing the differences between D. gni- or critical-point dried for S.E.M. examina- dium and the Anatolian D. gnidioides Jaub. & tion. Other organs from desiccated samples Spach [subsect. Oleoides Keissler], I think were directly gold-coated and observed with that the degree of persistence of the hypan- a JEOL JSM-T330A S.E.M. thium is taxonomically relevant. In D. gni- G. NIETO FELINER: DAPHNE MAURITANICA, SP. NOV. 193 Fig. l.-Holotypus of Daphne mauritanica. 194 ANALES JARDÍN BOTÁNICO DE MADRID, 53(2) 1995 Fig. 2.-Distribution oí Daphne mauritanica (solid squares) and D. gnidium (empty squares) in Northern África, based on herbarium material. dium, it is quickly ruptured and shed by the material (fig. 3a). In this species, hypanthia pressure of the developing fruit (fig. 3b), such 3.5-3.7 mm wide with enclosed developing that specimens never contain hypanthia more fruits are usually seen. I have not seen any in- than 3 mm wide (usually only up to 2.5 mm). cipient fleshiness in fruits of D. mauritanica. Instead, what is commonly seen in every in- Therefore, it is likely that the fruits never de- florescence are several naked, black, pyriform velop into the sort of red fleshy ones found in developing fruits. In D. mauritanica the hy- D. gnidium. Instead, they probably remain dry panthium is far more persistent and naked as apparently occurs in D. arbuscula Celak. fruits are seldom found among the herbarium (TAN, 1980). An alternative, although less li- Fig. 3.-Hypanthium in the fruiting stage: a, Daphne mauritanica (persistent); b, D. gnidium (already shed). (Scale 1 mm.) G. NIETO FELINER: DAPHNE MAURITANICA, SP. NOV. 195 kely, explanation for the lack of fleshy fruits usually overtops the apical leaves so that it is could be that similar or even lower levéis of clearly exserted. The greater exposure of the fruit-set than the ones detected in D. gnidium inflorescence is due to the faster elongatum of (HERRERA, 1987) are shown by D. mauritani- the raceme axis, to the longer raceme pedun- ca; this would make difficult the observation cle (hypopodium cf. WEBERLING, 1981: 12) of mature fruits in herbarium material. and to the fact that most racemes develop in Pubescence.-The easiest way to distin- the axils of bracts (which are more or less guish the new species from D. gnidium is to hairy) instead of in the leaf axils. By contrast, observe shoot pubescence. In D. gnidium, in D. gnidium most racemes develop in the new shoots are covered with short (< 0.25 axils of fully developed leaves which conceal mm) appressed hairs, which extend to the in- the slow growing raceme axes. florescence axis andpedicels. D. mauritanica, in contrast, presents glabrous shoots from the Architecture.-Shoot architecture is the starting point of the year's growth to the base same in both species. Innovation shoots arise of the inflorescence, so that pubescence is res- more or less crowded in leaf-axils at the base tricted to the reproductive structures (inflores- of the inflorescence, such that when leaves are cence axes, pedicels, hypanthia and sepáis). shed during the following season shoot divi- In the lower part of the inflorescence, hairs sión appears to be multi-forked as indicated tend to disappear along longitudinal Unes des- by WEBERLING & HERKOMMER (1989:60). cending from point of leaf insertion. Among Epidermis.-Two more distinguishing cha- hundreds of European and African speci- racters are found on the abaxial leaf surface. mens, I have seen four (2 from Almería, Spain This surface is glaucous in D. mauritanica, and 2 from Oran, Algeria) which, although probably because of the tight imbrication of belonging to D. gnidium, present glabrous the epidemial cells (fig. 4c) as compared to shoots. Therefore, despite being a useful and those in D. gnidium and probably also becau- easily observed character, pubescence should se of the cuticle. In the latter species, cells are be considered together with others.