New Taxa in Maerua (Capparaceae) Proposed for the Flora of Ethiopia

Abstract

During studies of Capparaceae carried out for the Flora of Ethiopia, the following new taxa in Maerua were discovered. Maerua intricata Kers, sp. nov. TYPE: Ethiopia. Ogaden: Mustahil to Ferfer, 5 Dec. 1954, Peggy E. Ellis 357 (holotype, K). A speciebus quas A. Brongniart et alii auctores ad Courboniam ascripserunt habitu intricato foliis minutis costa plerumque immersa ideo utrinque occulta distinguenda, ab eis etiam in combinatione petioli brevissimi (ut in M. pseudopetalosa (Gilg & C. Benedict) De Wolf) cum fructibus ellipsoidalibus basi regulariter per quattuor valvas dehiscentibus (ut in M. subcordata (Gilg) de Wolf) differt. Virgate shrub 0.5-2 m tall, intricately branched, stems erect or ascending, glabrous, ? minutely scabrous, branches and branchlets stiffly divaricate, somewhat striate. Leaves simple, minute, 5-15 mm long, 1-5(-8) mm wide, stiff, coriaceous, narrowly elliptic, oblong or lanceolate, seemingly often nerveless (midrib imbedded), petiole very short, 0.51.5(-2) mm long. Flowers without petals, solitary and axillary; pedicel short, 7-11(-13) mm long; receptacle cylindric, (2-)3-4.5 mm long; sepals three, (6-)8-10 mm long; androgynophore finally exceeding the receptacle by 1-2.5 mm; stamens ca. 20-25; gynophore 12-16 mm long, longer than the pedicel; ovary fusiform, 4-nerved; placenta 2, ovules two on each placenta. Fruit broadly ellipsoid, with one or rarely two seeds, pericarp finally breaking up into four valves at the very base of the fruit, otherwise indehiscent. Seed (9-)14-15 mm long, narrowly ovate to oblong, cotyledons pale yellowish. Maerua intricata is clearly allied to the species of Maerua that were formerly grouped in the genus Courbonia Brongniart. It differs in the intricately branched growth, the minute leaves with a generally completely immersed and consequently hidden midrib. The petioles are as short as in M. pseudopetalosa, whereas in shape and mode of dehiscence the fruits are comparable with those of M. subcordata. Distribution. Known from the area around the River Schebelli in eastern Ethiopia and central Somalia and from there north into the African Horn of the northeastern Somali Republic; from 100 m near the coast to 350 m inland. Habitat. In Acacia-Commiphora bushland or in scattered low bush. Growing on rocky slopes, in stony soil at foot of hills, in sandy areas with limestone ridges or in dry water courses. Indigenous names. Cagat, cagah (Bari region), Dugal erigiren (Hiraan region). Paratypes. ETHIOPIA. OGADEN: Scivelli to Beletuen, June 1943, Hummel 151 (K); Webi (= Schebelli River), July-Aug. 1891, Robecchi-Brichetti 228 (FT). SOMALIA REPUBLIC. SANAAG REGION: below Einad, 11055'N, 48?55'E, 1957, Newbould 1022 (K). BARI REGION: Alula, without date, Anonymous s.n. (FT fragments); along road from Alula to Seyn Wayn, 9 Oct. 1982, Barbier 939 (FT, K); near Bender Merhagno, 11041'N, 50?27'E, 15 Oct. 1982, Barbier 946 (K); Mt. Bolimock W of Alula, 29 Oct. 1959, Hemming 1786 (K); 40 km SW of Alula, 11055'N, 50'30'E, 14 Nov. 1980, Hemming & Watson 3087 (K); near Bosaso, to Cassim Bender, 7 July 1924, Puccioni & Stefanini 1034 (= 1136) (FT); Wadi Merero, Scortecci, 1957 (FT); mountain pass W of Bargal, ca. 11?15'N, 51000'E, 25 Nov. 1985, Thulin & Warfa 5532 (UPS); mountains S of Bender Murrayha, valley above Tayeega, 29 Oct. 1959, Thulin & Warfa 5814 (K, UPS). NUGAAL REGION: valley slope of Nugal River, 7 Oct. 1959, Hemming 1679 (K). MUDUG REGION: 69 km SW of Galkayo on main road, 06027'N, 46'53'E, 4 June 1979, Gillett, Hemming & Watson 22347 (K). HIRAAN REGION: 03006'N, 45004'E, 1 Aug. 1983, Abukar Sheik 2023 (K); Bulo Burti district, 4 km N of Murkayale, 03050'N, 45013'E, 28 Sep. 1986, Kuchar 17082 (K); El Mocoile, on road from Bulo Burti to Galgiel, 5 Apr. 1933, Suckert 66 (FT, K). Figure 1. Maerua intricata Kers. -A. Portion of stem with flowering twigs. -B. Portion of stem with immature fruits. -C. Ovary in transversal and longitudinal sections. -D-F. Leaves. -G. Gynophore with ovary, torus with stamen scars, androgynophore. -H. Flower. -I. Mature fruit showing the basal dehiscence, seed partially exposed. NOVON 3: 50-54. 1993. This content downloaded from 157.55.39.104 on Mon, 20 Jun 2016 05:54:48 UTC All use subject to http://about.jstor.org/terms Volume 3, Number 1 1993 Kers