Minuartia alpuensis Çilden & Altınözlü, 2020

Çilden, Emre & Çelemli, Ömür Gençay, 2020, Minuartia alpuensis (Caryophyllaceae), a new endemic species from inner Anatolia, Turkey, Phytotaxa 443 (1), pp. 79-91 : 81-84

Minuartia alpuensis Çilden & Altınözlü sp. nov. ( Fig. 1 )

Type: — TURKEY. B3 Eskişehir: Alpu, Kireçköy, rocky areas southwest of the village, 990 m elevation, 4404500N, 309547E, calcerous fields, 27 Aug 2019, E. Çilden 1947 (holotype: HUB!, isotypes: ANK!, GAZI!).

Description: —Caespitose, whitish, perennial herb, densely pubescent (hairs 0.2–1.1 mm long). Stems erect, 7–15 cm long, branched from the base. Leaves subulate, 4–6 × 0.25–0.5(–1.0) mm, 3-veined, acute to acuminate at apex, with margins membranous and ciliate at the base; leaf fascicles open at flowering time. Bracts linear-lanceolate, 4–4.5 × 1.5–1.7 mm, 3-veined, acute to acuminate at apex, with membranous margins (0.1–0.4 mm). Inflorescence a cymose cluster of 2–4 flowers; flowers pedicellate, pedicels 1–1.5 mm, erect. Sepals linear-lanceolate, 4.5–6.0 × 1.0– 1.5 mm, with 1 distinct midvein, membranous along margins, long-acuminate at apex. Petals oblong-elliptic, 4.0–4.5 × 1–1.5 mm, 2/3 as long as sepals, white, obtuse at apex. Stamens 10; filaments (3.5–) 4–5 mm long; (staminal glands 5, prominent, bipartite, placed at the base of outer filaments, whitish-orange). Styles 1.5–2.0 mm. Capsule ovoid, 3–4 × 1.0– 1.3 mm, 3–5 seeded. Seeds oblong and reniform, 0.5–0.7 × 0.1–0.3 mm, brown or dark brown, the surface tuberculate in the central area, tuberculate with papillate tubercles dorsally.

Etymology: —The epithet alpuensis is derived from the type locality in Alpu district (Eskişehir province), inner Anatolia, Turkey. The Turkish name is suggested here as “Alpu tıstısı”.

Ecology: —The vegetation of the area where Minuartia alpuensis is found is a inner-Anatolian steppe ( Fig. 2 ), on calcareous substrate between 950−1000 m elevation. The newly described species occurs with Fumana aciphylla Boissier (1867: 449) , Helianthemum nummularium ( Linnaeus 1753: 527) Miller (1768 : Helianthemum num. 12), Dianthus zonatus Fenzl (1842: 11) var. zonatus , Linum bienne Miller (1768 : Linum num. 8), Rhamnus thymifolia Bornmüller (1931: 33) , Onobrychis armena Boiss. & A.Huet in Boissier (1856: 36), Agrimonia eupatoria Linnaeus (1753: 448) , Cerasus prostrata ( Labillardière 1791: 15) Seringe in Candolle (1825: 538) var. prostrata , Sanguisorba minor Scopoli (1771: 110) subsp. balearica (Bourg. ex Nyman 1878: 240) Muñoz Garmendia & Navarro (1998: 176) ( Poterium sanguisorba subsp. muricatum Spach ex Bonnier & Layens 1894: 102 ), Bupleurum sulphureum Boiss. & Balansa in Boissier (1859: 74), Scandix pecten-veneris Linnaeus (1753: 256) , Torilis arvensis ( Hudson 1762: 98) Link (1821: 265) subsp. arvensis , Centaurea urvillei Candolle (1838: 592) subsp. stepposa Wagenitz (1972: 489) , Sedum album Linnaeus (1753: 432) and Crepis foetida Linnaeus (1753: 807) subsp. rhoeadifolia ( Marschall von Bieberstein 1808: 259) Čelakovskı (1871: 190) .

Distribution: — Minuartia alpuensis is an Irano-Turanian element, apparently endemic to Eskişehir province (Alpu and Seyitgazi districts), in the inner Anatolia region. It is only known from two places, the type locality in Kireçköy village (Alpu district), and a second site close to Yukarısöğüt village (Seyitgazi district), around a marble quarry.

Phenology: —July–August (flower), August–September (fruit).

Conservation status: —The two known populations of the species include about 225–250 individuals, namely 150 in the type locality (Alpu district) and ca. 75–100 individuals in Yukarısöğüt village (Seyitgazi district), around a marble quarry (E. Çilden pers. obs.). But due to the pressure of the marble quarry at the second population, the number of mature individuals would be declining. Under IUCN criteria (2012) and according to IUCN guidelines (2019), this data allow the classification of Minuartia alpuensis in the “Endangered” (EN) category under subcriteria “B1, B2 a,c(ii, iv); D”, because the reduced number of locations (≤ 5) and the scarce number of mature individuals (≤ 250).

Taxonomic notes: —According to McNeill (1963), some species found in the montane and subalpine steppe habitats, including M. tchihatchewii ( Boissier 1854: 243) Handel-Mazzetti (1912: 148) and M. anatolica ( Boissier 1849: 97) Woronow in Woronow & Schelkownikow (1914: 92), exhibit an extraordinary diversity of forms, as Mattfeld (1921) had already reported. The former author also indicated that a large number of taxa, each with a distinctive geographical and ecological range might become recognisable. Furthermore, later he ( McNeill 1967) also remarked the morphological heterogeneity existing in Minuartia , and pointed out to the importance and need of further investigations on the evolutionary status, the breeding system and the interrelationships of all species in the genus in Turkey.

In the light of these inferences, we have studied six related taxa which are alike and seem to have evolutionary affinity with M. alpuensis . Minuartia alpuensis belongs to sect. Minuartia , which is characterised by the conical calyx, hardened and rounded to truncate base and capsule included in the calyx ( McNeill 1967, Halliday 1976). The species is related to Minuartia hamata (Hausskn. & Bornm. ex Haussknecht 1891: 17) Mattfeld (1921: 29) , M. leucocephala ( Boissier 1843: 45) Mattfeld (1921: 30) , M. tchihatchewii (Boiss.) Hand. -Mazz., M. anatolica (Boiss.) Woronow var. arachnoidea McNeill (1963: 371) , M. anatolica var. phrygia ( Bornmüller 1909: 449) McNeill (1963: 373) and M. anatolica var. polymorpha McNeill (1963: 373) . However, M. alpuensis differs from the related taxa by its whitish habit, densely pubescent indumentum, distinctly one veined bract, and capsule and seed dimensions. Table 1 shows the main morphological relationships of those cited taxa.

Palynology: —The pollen grains of the family Caryophyllaceae are usually radially symmetrical, pantoporate, rarely 3−10-colpate, spheroidal or prolate-spheroidal, sub-prolate to rarely prolate. Sexine is thicker or thinner than nexine, and tectum spinulose-punctate or scabrate-punctate often reticulate or reticulate-scabrate ( Perveen & Qaiser 2006). In the present study, it is found that M. alpuensis and related taxa show a microechinate ornamentation (except for M. leucocephala that is microechinate-perforate), porate or pantoporate aperture types, and spheroidal shape (except for M. anatolica var. polymorpha that is prolate-spheroidal) ( Table 2, Fig. 3–4 ).

The palynological data reveal interesting differences among the studied taxa. Minuartia alpuensis shows the highest values of polar axis (P = 33.21 ± 0.98 µm), equatorial axis (E = 33.15 ± 1.21 µm) and annulus (1.56 ± 0.5 µm) in comparison with the related taxa. It is also observed that M. alpuensis and M. leucocephala are the closest taxa according to these parameters. Pore latitude (plt) values are similar in grains of M. alpuensis (plt = 4.6 ± 1.13 µm), M. leucocephala (plt = 3.62 ± 0.83 µm) and M. tchihatchewii (plt = 3.82 ± 0.48 µm). The highest values for exine and intine are found in M. leucocephala (exine: 2.15 ± 0.27 µm; intine: 0.46 ± 0.38 µm), whereas those values are similar to each other in M. hamata (exine: 1.66 ± 0.44 µm; intine: 1.53 ± 0.17 µm), M. anatolica var. arachnoidea (exine: 1.51 ± 0.25 µm; intine: 0.68 ± 0.19 µm), and M. tchihatchewii (exine: 1.38 ± 0.31 µm; intine: 0.35 ± 0.06 µm). More interestingly, the pores of M. alpuensis are sunken, but they are prominent in the remaining taxa. Accordingly, pore features seem to be a useful parameter for distinction of the newly described species and its morphologically closest relatives.

It has to be stated here that the analised palynological parameters are very similar in the studied varieties of M. anatolica ( M. anatolica var. arachnoidea , M. anatolica var. polymorpha and M. anatolica var. phyrgia ). However, some interesting data have been obtained that support segregation of var. phyrgia with regard to var. polymorpha , of which some authors have sometimes considered to be not more than a local glandulose form. The spheroidal shape of grains and higher values of pollen parameters obtained for M. anatolica var. phyrgia , together with the dense glandular pubescence covering the entire plant, allow easy characterisation and hence recognition of that variety as a distinct taxon, according to McNeill (1963).

In the light of all the morphological and palynological data, M. alpuensis can be confidently considered at species rank, and its closest morphological affinities correspond to M. leucocephala , M. anatolica var. arachnoidea and M. tchihatchewii .

Figures

FIGURE 1. Minuartia alpuensis. A. Habit; B. Inflorescence; C. Densely pubescent stem with leaves; D, F. Flower; E. Longitudinal section of a flower with mature capsule; G. Bract; H. Sepal with distinct mid-vein; I. Petal; J. Mature capsule; K. Seed.

FIGURE 2. General view of Minuartia alpuensis in habitat (A−B), and a close view of the species (C−D).

FIGURE 3. Light microscope pollen photographs; Minuartia hamata (A−B), M. leucocephala (C−D), M. tchihatchewii (E−F), M. anatolica var. arachnoidea (G−H), M. anatolica var. phrygia (I−J), M. anatolica var. polymorpha (K−L), and M. alpuensis (M−N).

FIGURE 4. SEM micrographs of pollen grains of Minuartia alpuensis (A–D) and M. leucocephala (E–F).