IntroductionThe preparation of the Catalogue des plantes vascularies du nord du Maroc (Valdés & al. 2002) was preceeded by a series of collecting trips by members of the Institute Agronomigne et Veterinaire Hasan II of Rabat, the University of Seville's Department of Plant Biology and Ecology, the Plant Science Laboratories of the University of Reading and the Botanical Institute of Barcelona, particularly from 1992 to 1996. This resulted in the collection of over 30,000 gatherings in this period, which constituted the base for preparation of the Catalogue. But this material was supplemented by the study of other plant material from N Morocco, kept in several herbaria, particularly BC, SEV and RDG, and to a lesser extent, in MPV, BM, K and EDBG (Valdés & al. 2002: 5-7) For chorological purposes the territory covered by the Catalogue was divided into 20 natural areas and the distribution of each recognized species or subspecies was given by the natural areas in which it was known.New explorations in N Morocco following the publication of the Catalogue have in-
134The contribution to the chorological knowledge of N Moroccan vascular plants creased the number of records of the different taxa for the different chorological areas. These new records have been published mainly by Aafi & al. (2005), Ajbilou & al. (2007), Benning (2004), Carine & al. (2006), Chambouleyron (2012), Ennabili & Gharnit (2003), Hammada & al. (2004), Luceño & Escudero (2006), Luceño & Marín (2002), Mateos & Valdés (2003a-d, 2004, Molero & Montserrat (2006a-c), Montserrat & al. (2006), Navarro & al. (2002), Ortega-Olivencia & Devesa (2004), Pinto & al. (2011), Pyke & al. (2008Pyke & al. ( , 2009, Romero Zarco (2009), Romo & Soriano (2004, 2005, Soriano & Ibañez (2008), Soriano & Romero (2008), Talavera & al. (2003aTalavera & al. ( , b, 2004Talavera & al. ( , 2008, Terrab & al. (2006a, b), Valdés (2005Valdés ( , 2011, Valdés & al. (2004aValdés & al. ( , b, 2005aValdés & al. ( , b, 2006a, and particularly by Dobignard (2009), who assigned to the different natural areas recognized in the Catalogue new records coming from his rich collections of N African plant material. Consequently, the floristical knowledge of N Morocco is now much more complete than in 2002.Unfortunately, with some exceptions, the material collected during Iter Mediterraneum V of OPTIMA in 1992 was unavailable to the authors contributing to the Catalogue, as the material collected was labelled and incorporated into the herbaria only in Berlin (B) and Reading (RDG), and remained unlabeled in the different centres of the participants in the Gharb; 5, Atlantic coast; 6, Ouezzane; 7, Central Rif; 8, Targuist; 9, Zerhoun; 10, Central Pre-Rif; 11, High Ouerrha; 12, Tazekka; 13, Tsoul; 14, Aknoul; 15, Imzorène; 16, Kert Ganc; 17, Gareb; 18, Guercif; 20, Forêt de la Maâmora (according Valdés & al. 2002). Bocconea 26 -2013 135 Iter. Study of this material would have increased the chorological knowledge of many of the taxa, as many plants were collected in areas not frequ...