A foundation monograph of Convolvulus L. (Convolvulaceae) Author Wood, John R. I. Department of Plant Sciences, South Parks Road, University of Oxford, OX 1 3 RB, UK & Honorary Research Associate, Royal Botanic Gardens, Kew Author Williams, Bethany R. M. Department of Plant Sciences, South Parks Road, University of Oxford, OX 1 3 RB, UK & Department of Life Sciences, Natural History Museum, Cromwell Road, London SW 7 5 BD, UK Author Mitchell, Thomas C. Plant Biodiversity Research, Technische Universitaet Muenchen, Maximus-von-Imhof Forum 2, 85354 Freising, Germany Author Carine, Mark A. Department of Life Sciences, Natural History Museum, Cromwell Road, London SW 7 5 BD, UK Author Harris, David J. https://orcid.org/0000-0002-6801-2484 Royal Botanic Garden Edinburgh, 20 A Inverleith Row, Edinburgh EH 3 5 LR, UK Author Scotland, Robert W. Department of Plant Sciences, South Parks Road, University of Oxford, OX 1 3 RB, UK robert.scotland@plants.ox.ac.uk text PhytoKeys 2015 2015-06-18 51 1 282 http://dx.doi.org/10.3897/phytokeys.51.7104 journal article http://dx.doi.org/10.3897/phytokeys.51.7104 1314-2003-51-1 E76E3938E216FF804849B803C469FE14 576310 173. Convolvulus hamrinensis Rech.f., Anz. Oesterr . Akad. Iss., Math.-Naturwiss. Kl. 98: 11. 1961. (Rechinger 1961: 11). Figure 25, t. 36-42 Convolvulus oxyphyllus subsp. sheilae R.R.Mill, Edinburgh J. Bot. 70: 376. 2013. ( Mill 2013 : 376. Type. SAUDI ARABIA, Collenette 2836 (holotype E!; isotype K!). Convolvulus infantispinosus R.R.Mill, Edinburgh J. Bot. 70: 374. 2013. ( Mill 2013 : 374). Type. SAUDI ARABIA, Collenette 2210 (holotype E!; isotype K!). Type. IRAQ, Rechinger 8083 (holotype W!; isotype E00699568!). Description. Undershrub with spinescent branches forming a low bush to 60 cm high and up to 1 m wide; young branchlets white-tomentellous, side branches rather short, c. 5 cm long, sometimes spine-like. Basal leaves 0.5-3 x 0.3-0.6, oblanceolate, obtuse, margin undulate, base attenuate into a long petiole-like base, densely puberulent on both surfaces, paler beneath; stem leaves and bracts 3 x 2 mm, oblong to oblanceolate, obtuse to subacute, cuneate at base. Flowers 1 (-2), sessile in the axils of bracts; bracteoles 2 x 0.5 mm, linear-oblong, pedicels 0-1 mm; sepals 5-6 x 2-3 mm, oblong to oblanceolate, obtuse, densely pilose; corolla 0.6-1cm long, white, slightly lobed, midpetaline bands pilose; ovary hirsute, style glabrous, divided c. 4 mm above base, stigmas 4 mm. Capsule not seen. Distribution. Locally abundant principally in sandy desert: Syria (?); Iraq ( Guest et al. 16151B, Mohallal 19504, both sterile); Saudi Arabia: Jouf, Hail, Riyadh to Eastern Province. Mandaville 199, 217, 2271, 2328, 2465, 2485, 3124, 3208; Popov 69/224, 72/57: Chaudhary 3467; Wood 71/269; Philby s.n. [15/8/1931]; Vesey-Fitzgerald 15888; Hillcoat 364; Dickson 1074; Collenette 97, 1851, 5332, 7214, 7879, 7883, 7886. The type is from east of Baghdad but the numerous records from Saudi Arabia seem indistinguishable. Notes. Arabian specimens of this species have been misidentified as Convolvulus lanatus . The type of Convolvulus infantispinosus ( Collenette 2210) has more delicate spines but seems to be only a form of Convolvulus hamrinensis . This species possibly intergrades with Convolvulus oxyphyllus but is nearly always easily identified. The plant has a characteristic appearance with short rigid spine-like side branches to the stiff woody spinescent main stem. Leaves and bracts are typically obtuse, the lower leaves petiolate. Flowers are solitary (rarely paired) axillary, usually much exceeding the rather inconspicuous bracts. At one extreme a few specimens ( Collenette 5351, Rechinger 9886, Chaudhary 3467, Omar et al. 43961) have acute leaves and bracts, clearly approaching Convolvulus oxyphyllus . At the other extreme, specimens with obtuse, undulate leaves and bracts are found ( Collenette 1851, 5332, 7874, Mandaville 7850). Collenette 1851 is especially close to the type of Convolvulus hamrinensis .