FIRST CONFIRMED RECORD OF CAREX LIMOSA L. (CYPERACEAE) AND COMMUNITY CARICETUM LIMOSAE BR.–BL. FOR NEVESINJSKO POLJE (BOSNIA & HERZEGOVINA)

During the field investigation of wetland flora and vegetation conducted on carstic terrains of Nevesinjsko polje (Bosnia & Herzegovina) we discovered numerous individuals of Carex limosa L. This Arctic–boreal relic species is remarkably rare in Southeastern Europe with only several known records across Balkans and few recent records for Bosnia & Herzegovina. Its habitat in Nevesinjsko polje can be described as an transitional mire with pronounced Sphagnum turfs on top of which C. limosa forms almost homogenous, species–poor stands of community Caricetum limosae Br.–Bl. In this article is presented the short account of this first confirmed record of C. limosa for Nevesinjsko polje (Bosnia & Herzegovina).


Introduction
With more than 2000 known species occuring on various habitats worldwide (especially in the Northern Hemisphere) the genus Carex L. is one of the most diverse groups of vascular plants with intricate taxonomical and phytogeographical background (Egorova 1999;Ball & Reznicek 2003). This perceived complexity with consequential identification errors is, beyond reasonable doubt, great impediment to the better knowledge concerning the distribution of many species of Carex and at the same time powerful driving force resulting in a number of recently described new species, even in Europe (e.g. Štěpánková 2008; Molina et al. 2008;Jiménez-Mejías & Luceño 2009).
The abovementioned discrepancy is even larger in the case of Bosnia & Herzegovina: although flora studies here have been pursued by the some of the most eminent botanist for more than 150 years, the vascular flora and especially diversity of Carex, remain still insufficiently explored (Milanović 2014(Milanović , 2017. 19: 152-158 (2018) This journal is available online at: www.biotaxa.org/em During the investigations of wetland flora and vegetation fragments preserved on carstic field Nevesinjsko polje we had discovered numerous individuals of Carex limosa L., a rare Arctic-boreal relic species with only a few known records across Balkans (see the text below). After a carefull examination of specimens and literature review we concluded that this is the first certain record confirming the existence of this rare species for Nevesinjsko polje (Bosnia & Herzegovina). Here we provide a brief description of this record with basic information about the species relating to its morphological traits, biology, regional distribution, habitat preferences and conservation status in Bosnia & Herzegovina.

Distribution in Bosnia & Herzegovina.
Despite the fact that this species has been recorded in neighbouring countries for decades ago and that favourable habitats are present in Bosnia and Herzegovina, this species has been reported for Bosnia & Herzegovina recently (Đug 2011: 106;Anonymous 2011: 455;Đug 2015: 96). In above mentioned publications C. limosa is listed as one of numerous species characteristic for habitat type "7140 Transitional mires". Whether this data are originating from original field work or they are merely included under the abovementioned habitat description in a manner per analogiam to other, similar manuals in neighbouring countries (Topić & Vukelić 2009;Anonymous 2013), the fact is that there are no cited particular localities nor voucher herbarium specimens in accessible herbarium collection supporting this claim, which is unfortunately not contributing to the scientific value of it. First published record of this species for Bosnia & Herzegovina with cited precise location emerged just recently (Milanović 2017), but without supporting voucher specimens in some publicly accessible herbarium collection. Author of this paper also indicates one more locality for Bosnia & Herzegovina (mt. Zelengora), but without any further details needed for its verification.
In this regard, according to our knowledge, the second confirmed habitat of C. limosa in Bosnia & Herzegovina is limited to the southern edge of transitional mire called Srednja Voda close to Nevesinje. The next records of C. limosa is ca. 40 km and 80 km east on Maglić and Durmitor mt. (Montenegro) respectively (Malý 1931-32;Rohlena 1942, Milanović 2017. Habitat. Sphagnum bogs and mires, margin of peat-lakes, swamp meadows, shores and watersides (Chater 1980;Ball & Reznicek 2003;Dai et al. 2011). Its habitat near Nevesinje can be described as acidic transitional Sphagnum-mire developed on Lower Triassic (Werfen) strata fractions (Riter-Studnička 1954). There individuals of C. limosa densely occupy no more than a few dozen square meters at the southern edge of mire forming numerous, small, scattered tufts of community Caricetum limosae Br.-Bl. which develop at the very top of Sphagnum hummocks. Accompanying species are Drosera rotundifolia L. and Sphagnum spp.

Conservation status.
As is the case with many other Arctic-boreal (glacial) relic species at warmer temperate latitudes of Northern Hemisphere, their rather rambling and rare occurrence in those areas appears to be profoundly influenced not only by the long-time changes in glaciation cycles and climate changes but also by various anthropogenic impacts and accompanying vegetation succession, which additionally contribute to the further decreasing and loss of boreal species stands across the warmer parts of Europe (Hegi 1923;Riter-Studnička 1956;Topić & Stančić 2006;Topić & Vukelić 2009). Threat status for this species published by Milanović (2017) as "endangered" (EN) (B2a, B2biii) is based on obsolete 2001 IUCN criteria. According to the most recent IUCN criteria (http://www.iucnredlist.org) threat status of C. limosa in Bosnia & Herzegovina can be estimated as critically endangered (CR B1a+ 2a).