Carex pachystachya Cham. ex Steud.

Raab-Straube, Eckhard von & Raus, Thomas, 2025, Euro + Med-Checklist Notulae, 18, Willdenowia 55 (1), pp. 107-144 : 118-121

Carex pachystachya Cham. ex Steud. – Fig. 10.

N It: Italy: Veneto, Dolomites, Belluno, Cortina d’Ampezzo municipality, below Rifugio Son Forca, 46°33'52.7"N, 12°10'52.4"E, 2073 m, Scirpus sylvaticus L. stand above small artificial lake, calcareous-dolomitic substrate, 10 Aug 2023, Lasen & Da Pozzo (ROV 80196, W, herb. Koopman, herb. Lasen). – On 28 August 2021, C. Lasen collected a Carex just below Rifugio Son Forca, near a ski slope, at the foot of Mte Cristallo, Dolomites, impressed by its unusual appearance. In January 2023, the collection was shown to F. Prosser, who suspected that it might be an allochthonous species. However, the collect- ed plants were without basal parts, as Bruno Wallnöfer, Vienna (in litt.) pointed out to us, which complicated the already difficult determination. Therefore, C. Lasen and M. Da Pozzo carried out a second collection including basal parts on 10 August 2023. The site consists of a stand of subdominant Scirpus sylvaticus L. with numerous other Carex species: C. ferruginea Scop. , C. flacca Schreb. , C. flava L., C. hirta L., C. nigra (L.) Reichard, C. panicea L., C. paniculata L. and C. sempervirens Vill. The site is located at the edge of a ski slope and just upstream of a reservoir for artificial snow and therefore in an area that has been subject to considerable disturbance for several years. At the end of 2023, samples with underground parts were sent to J. Koopman. A review of the Carex species introduced in Europe on the basis of Koopman’s monograph (2022) showed that the Son Forca plant corresponded in particular to C. pachystachya . A check of the Flora of North America ( Mastrogiuseppe & al. 2002) confirmed the determination, although the key presented in this work is rather complex due to the large number of species treated in this section. Finally, J. Koopman reported that two U.S. Carex experts, Barbara Wilson and Adolf Ceška, whom he had asked in turn for their opinion, were also of the same opinion.

This is a Carex belonging to C. sect. Cyperoideae G. Don, tufted, with stems 50–70 cm tall, slender, smooth, and leafy in the basal half. The leaves are 2–3 mm wide and not more than 20 cm long. The inflorescences are contracted, wholly brown, c. 1.5 cm long, consisting of 3–7 closely spaced spikes bearing male flowers at the base. At the base of the inflorescence is a usually scarious and very short bract, rarely linear. The utricles are erecto-patent, greenish brown, c. 3 mm long, broader at the base, flattened, narrowed into a beak rough at the margin, with a barely noticeable wing, with two stigmas. The glumes are brown, paler at the margin, almost as long as the utricles. This description was made based on plants from Son Forca and is consistent with that reported by the Flora of North America ( Mastrogiuseppe & al. 2002). Among the autochthonous species in N Italy, the inflorescence is reminiscent of that of C. diandra Schrank , which however is excluded by the spikes with male upper flowers and the margins of the utricles less distinctly winged, as well as by the different ecology: C. diandra is a distinctly marshland species. It may also be reminiscent of weak plants of the C. spicata group, which however also have spikes with male upper flowers. Carex pachystachya is a species that grows in W North America and E Asia (Kamchatka) ( POWO 2024e). In North America, it grows in cool, moist meadows, on lake shores and along forest margins ( Mastrogiuseppe & al. 2002). Outside this range, it is reported as introduced in Europe only in Sweden ( POWO 2024e),

where it was mentioned at first as C. macloviana d’Urv.

by Marscher (1990), subsequently corrected to C. pachystachya by Erik Ljungstrand

(in Åström 2003) as keyed out in Flora of North America. Wallnöfer & Essl (2016)

reported it as casual for Sweden; however, reports have now multiplied throughout the S part of Sweden ( GBIF

2024b). There is also a find-

ing for Germany (near Heil-

bronn, Baden-Württenberg,

18 May 2018, photos: https:// Fig. 9. Thladiantha dubia , flowering branch. – Crimea, Simferopol , 28 Jul 2013, photograph by A. V. Yena .

www.inaturalist.org/observa tions/12673247) by Walter

Plieninger, confirmed by Barbara Wilson. In Son Forca, Batum district, between Dagua village and Churuk-Su, the population can be estimated at around 20–25 flower- bogs, 23 Aug 1911, Vvedenskiy 3740 (TBI 1054413); ing heads on an area of 12–15 m 2. During the visit in ibid., [Adjara] Batumi Botanical Garden, as weed in 2023, there was no evidence of any expansion compared nursery, 24 Nov 1938, Popov (BATU 002828); ibid., [Adto the situation in 2021, but rather a slight decrease. De- jara] Batumi Botanical Garden, wet grassy slope, 21 Oct spite this, taking into account that the species is slowly 1970, Davitadze (BATU 002841); ibid., Adjarian ASSR, expanding in Europe, we consider C. pachystachya to be Kobuleti, ditches in low-laying places, 27 Oct 1952, naturalized in Italy. However, only future observations Dmitrieva (BATU 002840); ibid., [Adjara, Kobuleti muwill provide a definitive assessment of the status. nicipality] Batum region and vicinity, bank of Choloki M. Da Pozzo, J. Koopman, C. Lasen & F. Prosser River near its mouth, wet sand, 27 Jul 1917, Worornow (TGM 5770); ibid., [Adjara, Kobuleti, Tsikhisdziri] Cyperus colchicus K. Koch (≡ Pycreus colchicus (K. Batum region and vicinity, Tsikhis-dziri, bogs, 26 Aug Koch) Schischk. ex Grossh. ≡ C. tremulus var. colchi- 1908, Rollov (TGM 5771); ibid., [Adjara, Kobuleti mucus (K. Koch) Kük.; = C. stachyphorus K. Koch ; = P. nicipality] Churukhsinskii canal, Kobuleti, 11 Aug 1926, woronowii Palla ≡ C. tremulus var. woronowii (Palla) Zedelmejer (TBI 1054323, TBI 1054330); ibid., [Adjara] Kük.) – Fig. 11A. Kobuleti, bog, 2 Sep 1927, Zedelmejer (TBI 1054325); + Gg: Georgia: Autonomous Republic of Adjara, Batumi, ibid., [Adjara, Kobuleti, near Chakvi] Transcaucasia, Gonio, Apsaros 1 st dead end, 41.57866°N, 41.57247°E, Georgia, Adzharistan, prope p. Tchakva, 4 Oct 1927, Mawasteland in private garden, on excavated wet red-earth kashvili (TBI 1054328); ibid., [Adjara, Kobuleti] Kobusoil, 17 Sep 2023, Vishnyakov (BR, IBIW 76530; photos: leti bogs, 29 Sep 1956, Erkomaishvili (TBI 1054335); https://www.inaturalist.org/observations/183831954). ibid., [Adjara, Khelvachauri, Salibauri] Transcaucasia, Additionally studied specimens: [Adjara, Khelvachauri Georgia, Adzharistan, Kobulety district, Salibaur, 6 Sep municipality, Kiziltoprakhi] Russian Lazistan, in swampy 1926, Makajev (TBI 1054329); Guria [Ozurgeti municiareas near Kyzyl-Toprakh, 24 Aug 1910, Woronow & pality], inter Natanebi et Ozurgeti, 4 Sep 1920, Gross- Popov 619 (TBI 1054400, TBI 1054416) [syntypes of heim (TBI 1054320, TBI 1054321, TBI 1054405); ibid., Pycreus woronowii ; in protologue: “in paludosis prope p. Guria [Ozurgeti municipality], Anaseuli, tea plantation, 6 Kyzyl-Toprach. 24. VIII. no 619”]; ibid., [Adjara, Khel- Nov 1934, Makashvili (TBI 1054322); [Guria, Ozurgeti] vachauri, near Gonio] Russian Lazistan, Khushtule near Transcaucasia, Georgia, pr[ope] Kutais, Ozurgety, 11 Gonie, bog, 27 Aug 1910, Woronow & Popov 620 (TBI Sep 1926, Makajev (TBI 1054324, TBI 1054331); ibid., 1054403) [syntype and isolectotype of P. woronowii ; [Samegrelo-Zemo Svaneti, Zugdidi municipality] Anakin protologue: “loc Chuštule prope p. Gonieh, ad mar- lia, wet place near water’s edge, 18 Aug 1988, Skhulukhia ginem paludis. 27. VIII. no 620”]; ibid., [Adjara, Khel- (TBI 1054332, TBI 1054333); ibid., [Samegrelo-Zemo vachauri, near Gonio] Russian Lazistan, Khushtule near Svaneti, Chkhorotsqu municipality, Mukhuri] Mingrelia, Gonie, bog, 29 Aug 1910, Woronow & Popov 620a (TBI Zugdidi district, in viciniis pag. Muchuri, 12 Aug 1923, 1054402) [presumably syntype of P. woronowii ]; ibid., Schischkin (TGM 5769).

[Adjara, Makhindjauri?] Batum district, between Ro- + Tu(A): [ Turkey: Artvin province, Kemalpaşa (former manovka village and Sultanovskaya dacha, bogs, 25 Aug Makriali)] Russian Lazistan, swampy bank of River 1911, Vvedenskiy 3738 (TBI 1054404); ibid., [Adjara] Makrial-Su near mouth, 25 Aug 1910, Woronow & Popov 618 (TBI 1054415) [syntype of Pycreus woronowii ; in protologue: “in paludosis prope p. Makrial. 25. VIII. no 618”]; ibid., [Artvin province, Kemalpaşa (former Makriali)] Russian Lazistan, Mokrial, rice field, 25 Aug 1910, Woronow & Popov 620b (TBI 1054417) [presumably syntype of P. woronowii ]; ibid., [Artvin province, between Sarpi and Kemalpaşa (former Makriali)] Russian Lazistan, between Sarp and Mokrial villages, small spring near road, 25 Aug 1910, Woronow & Popov 617 (TBI 1054414) [presumably syntype of P. woronowii ]. – Cyperus colchicus was originally described from the Kolkheti lowland in W Georgia (“ Imeretien, bei Choni”, Koch 1848). A similar species, Pycreus woronowii Palla , was described 64 years later by Palla (1912), also from Transcaucasia, with syntypes from NE Lazistan, a region now divided between Turkey and the Autonomous Republic of Adjara in Georgia. Schischkin (1935) included Palla’s species in P. colchicus (K. Koch) Schischk. ex Grossh. , but Kükenthal (1935 –1936) later reduced these two species to varieties of C. tremulus Poir. , viz. var. colchicus (K. Koch) Kük. and var. woronowii (Palla) Kük. , respectively. These and some morphologically similar taxa are characterized by biconvex nutlets with one edge facing the spikelet axis (therefore belonging to the former segregate genus Pycreus P. Beauv. ) and particularly by glumes with a broad hyaline margin. They were allocated by Kükenthal (1935 –1936) to the small C. sect. Albomarginati Kük. In more recent times, species from this section have been treated differently by various authors. However, two out of three species that were treated by Kükenthal (1935 –1936), C. albomarginatus (Mart. & Schrad. ex Nees) Steud. and C. tremulus , are now usually accepted as a single, variable and widespread species, C. macrostachyos Lam. (e.g. Hoenselaar & al. 2010; Mesterházy & al. 2022; POWO 2024i; but see Tucker & al. 2002). In contrast, C. tremulus var. colchicus is now commonly regarded as a distinct species, C. colchicus , which also includes P. woronowii and C. stachyphorus K. Koch , a species described from Trabzon in Turkey. According to Egorova (1991), records of C. (P.) tremulus for W Transcaucasia ( Schischkin 1935) should also be attributed to C. colchicus . The species is considered an E Euxinian endemic, with a very limited distribution in W Georgia (from Abkhazia to Adjara) and the adjacent part of Turkey ( Egorova 1991; POWO 2024h). However, only a few precisely localized records have been published ( Palla 1912).

The current treatment of Cyperus colchicus in the Euro+Med PlantBase leads to confusion. This species and its heterotypic synonyms were included in the synonymy of the unrelated species C. serotinus Rottb. ( Jiménez-MejÍas & Luceño 2011 +), apparently following Davis & Oteng-Yeboah (1985). Cyperus serotinus shares the biconvex nutlets with C. colchicus , but in C. serotinus the nutlets face the spikelet axis with one face, a characteristic of the former segregate genus Juncellus C. B. Clarke. However , after re-examining the type material, Egorova (1991) had already indicated that this synonymization was incorrect, but her findings unfortunately went unnoticed in Europe.

Despite being described from Georgia and mentioned in a recent national checklist ( Davlianidze & al. 2018, as Pycreus colchicus ), Cyperus colchicus remains one of the most obscure species of the contemporary flora. According to the Georgian Biodiversity Database ( Tarkhan-Mouravi & al. 2024), the presence of this species in Georgia is uncertain and requires specialist confirmation. Another possible explanation is that the species has apparently not been observed and/or collected for a long time, which leads to the assumption that it may be extinct. The most recent Georgian record indeed is from 1917 ( GBIF 2024c), with a note that the species was rath- er widespread on wet, sandy soils of the Kolkheti lowland (MW 0651859 [photo!]). The species has not been found in recent extensive studies of the Georgian wetlands, particularly in the Kolkheti lowland ( Tedoradze & al. 2023). Additionally, there are currently no records of this species from Turkey ( Şapci & Vural 2018), which may not only be due to erroneous identification with C. serotinus but also to the lack of new collections.

In the autumn of 2023, an unknown species of “ Pycreus ” was found on the Black Sea coast in Gonio (S of Batumi), in close proximity to the loci classici of P. woronowii . After an in-depth investigation, using relevant literature (particularly Schischkin 1935; Kükenthal 1935 –1936; Egorova 1991) and reference material, these plants were attributed to Cyperus colchicus . This new occurrence stimulated a search for additional specimens in the herbaria BATU, TBI and TGM. We found specimens from over two dozen localities in Georgia (regions of Adjara, Guria and Samegrelo-Zemo Svaneti) and Turkey (Artvin province). Most of them were collected in Georgia before 1927, with only six collected between 1934 and 1988. It was also discovered that TBI holds the type material of P. woronowii , represented by four syntypes from Woronow’s expedition to Adjaria and Lazistan in 1910, as well as several uncited specimens marked as “ Pycreus woronowii n. sp. ” (presumably syntypes). Two of the latter establish new localities for Turkey. The lectotype is designated here, a specimen from Palla’s Herbarium in GZU also seen by Kükenthal: