The genus Carex L. (Cyperaceae) is represented worldwide by about 2000 species (Govaerts et al. 2016). Of the 225 European species (Koopman 2015), 84 taxa belong in the Croatian flora (Nikolić 2019a, b). In the current century, some Carex species have been reported as new for Croatia or their presence has been confirmed for the Croatian flora. The first one, the occurrence of which in Croatia had previously been uncertain, is Carex buekii Wimm., found and confirmed by Alegro and Marković (1999) on the banks of the River Kupa. The occurrence of C. randalpina B. Walln. in the River Krapina valley was confirmed by Stančić (2009). Finally, C. punctata Gaudin was recorded by Koopman and Topić (2011) for three localities in wet grasslands, near the village Pisarovinska Bregana, the River Dretulja and in Risnjak National Park, and it was added to the national lists of vascular flora (Nikolić 2019a, b).

In June 2019, during field research on the vascular flora of Mt Mosor in central Dalmatia, a peculiar Carex population was found within deciduous sub-Mediterranean Quercus pubescens Willd. and Carpinus orientalis Mill. forests at an altitude of 1080 m a.s.l. Until then, according to Vladović (1994) and Nikolić (2019b), seven Carex taxa (C. caryophyllea Latourr., C. distans L., C. divulsa Stokes, C. flacca Schreb. ssp. erythrostachys (Hoppe) Holub, C. halleriana Asso, C. humilis Leyss., and C. otrubae Podp.) had been recorded for the flora of Mt Mosor. A morphological survey of the newly found Carex population from Mt Mosor, showed some distinctive characteristics, such as very long leaf-like bracts of the lower female flowers, which greatly exceeded the inflorescence. They are specific to C. phyllostachys C.A.Mey. the occurrence of which could thus be confirmed for the first time in the Croatian flora.

According to Chater (1980), in the European flora only C. phyllostachys and C. distachya Desf. belong to the subgenus Indocarex (Baillon) Kük., while Nilsson (1985) added C. illegitima Ces. to this subgenus. The Global Carex Group (2016) shows that C. phyllostachys is closely related to C. illegitima and C. oedipostyla Duval-Jouve, the latter from the Canary Islands, Southwest Europe and Northwest Morocco (Koopman 2015), while these three species are closely related to C. distachya. Most likely, C. phyllostachys is not closely related to the section Phyllostachyae in the grouping of which there are only species occurring in North America (Starr et al. 1999). Therefore, the sectional position of C. phyllostachys is less clear and needs further research (see also Więcław et. al. 2020).

The species C. phyllostachys was described and published by von Meyer (1831: 30) from Mt Talysh in Azerbaijan (Caucasus). It is rare within its wide distribution range and, according to Koopman (2015) and Koopman et al. (2017), it is known from eleven countries in southern Europe and nearby Asia. In Asia the species is known from Armenia (Khandjian 2001), Azerbaijan, Georgia and the Russian Federation (North Caucasus; Egorova 1999), Turkey (Anatolia; Nilsson 1985), Syria (Mouterde 1966), and it was mentioned for North Iran (Kukkonen 1987, 1998). In Europe it was known till the 1980s only from North Macedonia (Bornmüller 1924, 1928, Chater, 1980, Teofilovski 2011). Since then it has been found in Greece (Bergmeier 1988, Authier 1997), Albania (Barina and Pifkó 2011) and recently in Italy (Wagensommer et al. 2014) which is the westernmost distribution limit of this species so far. Carex phyllostachys has a scattered distribution, divided in three geographical areas, very far apart from each other: Caucasus and North Iran, south-eastern Turkey and north-western Syria, and the Balkans and Italy (Authier 1997, Wagensommer et al. 2014).

The present paper provides the first record of C. phyllostachys in the Croatian flora, which is the north-westernmost distribution limit of this species as far as is known. Morphological similarities with allied species (C. distachya and C. illegitima) and the habitat and ecology of C. phyllostachys in the Croatian flora are discussed. An identification key for Carex species belonging to subgenus Indocarex in Croatia is provided as well.

Carex phyllostachys C.A.Mey., Verz. Pfl. Casp. Meer. 30 (1831)

Synonym – Forexeta phyllostachys (C.A.Mey.) Raf., Good Book 28 (1840)

Typification – First-step, designated by Nilsson (1985: 88), as holotype: "[Transcaucasus] in sylvis umbrosissimis montium Talüsch, 530 hexap. [954 m], s.d., C.A. Meyer 180" (LE!); Second-step, indicated by Egorova (1999: 547), as "Typus", ead., hoc loco (LE!); Third-step, designated by Egorova (2006: 242), as lectotype: "Herb. Ledebour. Carex phyllostachys. En. cauc. casp. N 180, C.A.Meyer" (LE!), and here we designate the number of herbarium LE 01064315!. Isolectotypes: LE 01064316!, LE 01064317!. The type of C. pyllostachys was initially erroneously designated by Nilsson (1985: 88), the author indicating a holotype in LE and isotypes in G and K. According to the Art 9.10. of the ICN (Turland et al. 2018) such erroneous use of a term has to be treated as an error to be corrected. Afterwards, according to Art. 9.3. the type was correctly designated as lectotype by Egorova (2006: 242). The specimen stored in G (G 00798631!) was collected in 1842 and does not belong to the original collection (1829-1830) from before 1831, while the specimen kept in K is just a photograph of a specimen in LE.

Morphological description – (based on the Croatian material, Fig. 2): Perennial, monoecious, caespitose, glabrous plant. Stems 20–40 cm long; basal sheaths dark reddish-brown, firmly enclosing stem bases. Leaves green or greyish-green, 2–3 mm wide, equalling or exceeding the stem; ± flat, rather flaccid, scabrid. Inflorescence reduced to 1–2 bisexual spikes, each with 1–3 male flowers at the apex of the branch, and 2–5 female flowers at the base. The male part of the spike 1–2 cm, rather dense, glumes pale brown; female part very lax, lowest flowers often distant. The lower, female flowers lack normal glumes, but have very long bracts instead, leaf-like, 7–22 cm long, dilated at the base, far exceeding the inflorescence, with the function of glumes. Utricles olive-brown, 5–6 mm long, distinctly many-veined, abruptly contracted into a short beak; beak 0.5 mm, often somewhat scabrid, mouth ciliate. Stigmas 3; nut pale brown, trigonous.

Karyology – Chromosome number 2n = 56 (Więcław et al. 2020).

Phenology – Flowering from May to June, fruiting from June to July.

Distribution in Croatia – Central Dalmatia, Mt Mosor (Fig. 1).

Habitat and ecology – In Croatia, C. phyllostachys grows on the southern slopes of Mt Mosor within deciduous sub-Mediterranean forests of the alliance Fraxino orni-Ostryion at an altitude of 1080 m a.sl.l. It grows together with numerous mesophilous species, among others with Quercus pubescens, Carpinus orientalis, Fraxinus ornus L., Acer monspessulanum L., Ostrya carpinifolia Scop., Pistacia terebinthus L., Melittis melissophyllum L., Sesleria autumnalis (Scop.) F.W.Schultz, Rosa sp., Silene italica (L.) Pers., and Teucrium montanum L. Deciduous woodlands represent the primary habitat of C. phyllostachys, and therefore the Croatian population can be considered to be native. In fact, C. phyllostachys is a submontane species, known from altitudes usually ranging from 700 to 1800 m a.s.l., where it grows in deciduous forests (Nilsson 1985, Khandjian 2001). In Armenia it was found in a shaded broad-leaved forest, on steep slopes along a rivulet, as well as in humid places in a Quercus forest (Koopman et al. 2017). Similarly, in Italy it was found in a Q. pubescens forest, in the bed of a small dip at 400 m a.s.l. (Wagensommer et al. 2014). While most of the localities are in various deciduous forests, in Albania it was found in dry, open grasslands (Barina and Pifkó 2011), and the known habitats in Greece are also non-forest places (Authier 1997). Barina and Pifkó (2011) as well as Wagensommer et al. (2014) state grazing as the most serious threat to the species.

The species belonging to the subgenus Indocarex are morphologically characterised as monoecious, densely caespitose perennial plants, without creeping rhizomes, glabrous, with at least the terminal spike male at the apex, all spikes erect or nodding, lowest spike not pending, spikes lax, female flowers with 3 stigmas (Nilsson 1985, Egorova 1999). According to Chater (1980), C. phyllostachys and C. distachya are the only two species of the subgenus Indocarex occurring in Europe. Carex distachya is much more common in the studied region, and one of the characters which discriminates it from C. phyllostachys is the lower female bract which is shorter, reaching max. 5 cm (Authier 1997). Besides, C. distachya has normally developed female glumes, whereas C. phyllostachys has nude utricles; the elongate bracts have taken over the function of glumes (Egorova 1999). Another very rare and peculiar species is C. illegitima which has gynobasic lowest spikes, i.e. on long peduncles, arising from the base of the stem. Furthermore, C. distachya and C. illegitima are typically Mediterranean species growing primarily in evergreen Quercus ilex forests and in maquis.

Searching through the GBIF database, we noticed one record of C. phyllostachys from Croatia in Herbarium Senckenbergianum (FR 0120985!). The material was collected on 30 May 2014 from the Dubrovnik area, by Thomas Gregor and Lenz Meierott. In 2015, the reviewer of the material, Heinz Kalheber, thought it C. phyllostachys, which would mean that it was the first record of that very rare species from Croatia. Initially, Kalheber was not quite sure about his own determination, having written "könnte es sein" (could be), which has later been crossed out. We studied the scanned material from FR herbarium, and is our opinion this material from Croatia clearly does not belong to C. phyllostachys. There are too many female flowers, and they have normal female glumes, which are missing in C. phyllostachys. This specimen has only one, a bit longer bract, and in our opinion it clearly belongs to the much more common C. halleriana. Since in botanical literature no other information exists about the occurrence of C. phyllostachys in Croatia, our finding on Mt Mosor is indeed the first one.

Furthermore, the finding of C. phyllostachys in Italy by Wagensommer et al. (2014) was not the first one for the Italian flora. Chater (1980) was obviously unaware of some material from the Basilicata region in the Vienna herbarium (21 May 1977, leg. W. Burri and F. Krendl s.n., W 1994-0000725!), which was inserted in W after 1980. It was initially identified as C. depauperata With., but clearly belongs to C. phyllostachys (see Examined Specimens below). On the same day at the same locality, these collectors still found C. depauperata: “Basilikata: von Laghi di Monticchio zum M. Vulture, ca 700-1000 m, Eichen-Kastanien-Wald, vulkanisches Gestein” (W).

Wagensommer et al. (2014) discussed the phytogeographical connection of the Apennines, especially the Apulia region, and south-eastern Europe through some species with amphi-Adriatic distribution. The connection between the Apennines and the Balkans has also been discussed recently at community level (e.g. Di Pietro and Wagensommer 2014, Terzi et al. 2018). The new record of C. phyllostachys on the eastern Adriatic coast is interesting because it might represent another plant species, which underlines the connection between the Apennine and the Balkan flora.

Identification key for Carex subgenus Indocarex in Croatia

Examined specimens (specimina visa) – Armenia: Provinz Syunik, ca. 19 km SSE Kapan, Nerkin Hand, entlang dem Fluss E der Ortschaft, 680 m, 46.52972°E, 39.06083°N, 16 June 2016, R. Karl s.n. (GJO 0095051).

Azerbaijan: In sylvis umbrosissimis montium Talüsch, locis humidiusculis, alt. 530 hexap., s.d., C. A. Meyer 160 (LE 01064315, LE 01064316, LE 01064317); In humidis sylvarum umbrossimarum, Trans-Caucasia, 1831, C.A. Meyer s.n. (LE 01064318, LE 01064319); Mont Talysh, 1836, C.A. Meyer s.n. (P 01668651); In faucibus Yataghamanov-tshaj prope Lerik, in sylvis, 4 May 1915, A. Grossheim s.n. (MW 0653631); Talüsch, C.A. Meyer s.n., 1842 (G 00798631).

Georgia: Transcaucasia, Tiflis, in dumetis ad ostium fl. Armazis-tzchali prope stat. viae ferr. Mtzchet. 17 May 1923, B. Schischkin s.n. (MW 0653630, P 00293691).

Greece: Epire, nord-ouest Grèce, entre Vradeto et le Filakio, 1550 m, 2 June 1993, P. Authier s.n. (P 01668650, P 01668652); Thess., Kato Olimbos, zw.Kallipefki u. Kranea, Hangkante, mäßig beweidet, mäßig tiefgründig, real.frisch, c.1050 m ü.NN, grasige Fläche im Kontakt zu Q.coccif.-Gebüsch, zus. m. Carex praecox, 10 August 1986, E. Bergmeier 83-14v/3 (B).

Iran: Mazanderan, Harz Valley, Darli above Panjab, 2000 m, 52.283333°E, 36.166667°N, 30 July 1959, P. Wendelbo s.n. (E 00353692).

Italy: Basilikata: N-Seite des M. Vulture, knapp unterhalb der Gipfelregion, ca. 1200-1300 m, Kalkschläge in der Buchenwaldregion, vulkanisches Gestein, 21 May 1977, W. Burri & F. Krendl s.n. (W 1994-0000725, sub C. depauperata); Apulia, Prov. Bari, Santeramo in Colle, loc. Alessandrelli, Cula da Chioppo, UTM (ED50): 33T 0645 E 4515 N, 440 m, Quercus pubescens Willd. s. l. wood, at the ground of a small valley, 16 May 2012, R.P. Wagensommer, E.V. Perrino, G.N. Silletti s.n. (FI, BI).

North Macedonia: Bitola – nad s. Gorno Srpci, po kraevite na dabova šuma, silikat, 1000 m, 14 June 2009, A. Teofilovski s.n. (MKNH); Babuna Pass, c. 1000, 25 May 1918, H. Burgeff s.n. (B).

Syria: Slenfé, 24 June 1946, F. Louis s.n. (P 00293692, P 00293695); Attik Gheuzbel, 29 April 1937, F. Louis s.n. (P 00293693); Slenfé, s.d., F. Louis s.n. (P 00293694).

Turkey: Prov. Hatay dist. Belen (Amanus), Karlik tepe above Soguk Oluk, 900 m, tufted scrub on limestone, 24 April 1957, P.H. Davis, I.C. Hedge s.n. (E 00353694); Prov. Adana dist. Bahçe (N.Amanus): Dumanli Dag above Haruniye, 900 m, Ostrya scrub, 19 April 1957, P.H. Davis, I.C. Hedge s.n. (E 00353695); Prov. Adana dist. Bahçe (N.Amanus): Dumanli Dag above Haruniye, 700 – 900 m, in scrub on metamorphic slopes, 19 April 1957, P.H. Davis, I.C. Hedge s.n. (E 00353696); Quercetum, A6 Sivas: nsvr: Sußehri–Zara, Quercetum am Kußkayasi Geçidi, 1810 m, 3 June 1990, M. Nydegger 45622 (FR 0025713).