Trifolium elazizense M.Keskin, Sonay & Balos, 2023

Keskin, Mustafa, Sonay, Veysel & Balos, Mehmet Maruf, 2023, Trifolium elazizense (Fabaceae), a new species from Turkey, Phytotaxa 583 (2), pp. 199-206 : 202-204

Trifolium elazizense M.Keskin, Sonay & Balos , sp. nov. ( Figs. 1–3 )

Type: — Turkey. Elazığ: Karakoçan, Sarıcan district, Kejikan highland, north-facing slopes, step and cliffs, 2100–2300 m a.s.l., 11 June 2021, Sonay 1801 & M . M . Balos (holotype: HARRAN!, isotypes: NGBB!, ISTE!) .

Paratype: Turkey. Elazığ: Karakoçan, Sarıcan district, Kejikan highland, north-facing slopes, step and cliffs, 2100–2300 m a.s.l., 16 July 2022, M. M . Balos 5383 & Sonay ( HARRAN!) .

Diagnosis: — T. elazizense M.Keskin, Sonay & Balos is close to T. longidentatum Nábelek (1923: 69) and T. kurdistanicum Yousefi, Assadi & Ghaderi (2017: 217) but differs from them mainly for hairy stipules (tube equal to free parts); leaflets 25–35 mm, ellipticlanceolate, densely hairy; longest tooth always 3-nerved, others 1–3-nerved; fruiting calyx tube urceolate; fruiting calyx closed with callus hairs; seeds light brown, 1.4–1.6 mm, sunken.

Description:—Plants perennial with hard woody roots. Stems numerous, simple and erect, dense adpressed villous, 15–30 cm high. Stipules 18–30 mm long, adnate at base to petiole for less than half their length or only half, membranous between green nerves; free portion 10–13 × 4–5 mm, triangular-lanceolate, green, hairy on both surfaces or hairy at the margin, usually equal to adnate parts. Leaves crowded at base and long-petioled; petioles of the lower leaves 40–100 mm long, petioles of the middle leaves 15–30 mm and those of uppermost almost sessile; leaflets entire, ellipticlanceolate or oblong-lanceolate, 25–35 × 5–10 mm, mostly obtuse, hairy on both surfaces. Inflorescences usually 20 × 18 mm long, spherical, later somewhat elongated 30–40 × 20–25 mm, ovoid-oblong; peduncle 5–40 mm, densely adpressed villous. Flowers numerous, sessile, bracts absent. Calyx adpressed villous; tube 4–5 mm long, cylindrical with 10 prominent nerves; teeth of calyx unequal, erect, narrowly linear-subulate, plumose, sharp-pointed; longest tooth always 3-nerved, others 1–3 nerved, all longer than the tube; throat of fruiting calyx closed by callus hairs. Corolla pink or pinkish with dark striae 15–18 mm long, longer than calyx; standard oblong, much longer than wings and keel. Pod 3.5–4.2 mm long, membranous. Seeds 1, reniform, brown, 2.0– 2.5 mm long.

Etymology: The specific epithet of the new species refers to El-Aziz, the old name of Elazığ province in the east of Turkey, where the type specimen was collected.

Vernacular name: Since no local name can be observed, the name “rana yonca” is suggested (Gemici et al. 2016).

Ecology and habitat: The new species is associated with Genista albida Willd. , Prometheum sempervivoides (Fischer ex M.Bieb.) H.Ohba , Minuartia juniperina (L.) Maire & Petitm, Stachys lavandulifolia Vahl , Linum bienne Mill. , Bungea trifida (Vahl) C.A.Mey. , Polygonum alpinum All. , Rumex angustifolius L. subsp. angustifolius Campd. and various grasses.

Phenology: Leaf sprouting begins in April; flowering lasts from June to July; fruiting is completed by the end of July.

Conservation status: On the basis of the IUCN (2022), 1) less than 500 mature individuals were observed at the type locality, 2) AOO is 10 km 2, 3) no imminent threat to the habitat of this new species occurs (but some human pressure is expected in the future), and 4) two localities close to each other can be found. According to criteria D1 and D2, the species can be assessed as Vulnerable (VU).

Taxonomic comments: According to the classification of Zohary & Heller (1984), T. elazizense appears to belong to sect. Trifolium subsect. Ochroleuca Gib. & Belli. However , due to their stipule character and their different stances from the species in the subsection Ochroleuca , it was deemed appropriate to collect T. elazizense M.Keskin, Sonay & Balos , T. longidentatum Nábelek , and T. kurdistanicum Yousefi, Assadi, & Ghaderi into a new subsection: subsect. Stipulia M.Keskin.

T. elazizense M.Keskin, Sonay & Balos differentiates based on some distinct morphological characteristics such as: hairy stipules (tube equal to free parts), callus hairs, and longest tooth with three-nerved, others one-nerved. It has close affinity with T. longidentatum Nábelek ( Nábelek 1923) (endemic to Turkey) and T. kurdistanicum Yousefi, Assadi, & Ghaderi ( Yousefi et al. 2017; Rastegar et al. 2020) (endemic to Iran).

T. elazizense resembles T. longidentatum and T. kurdistanicum in terms of basic characters. These three species are unique in their stipul character in the genus Trifolium . For this reason, they are studied in the Stipulia subsection. The new species differs from allied species in terms of their basic distinguishing characteristics, such as its short habit and, branched stem, beautiful hair cover. In addition, the growing area is unique. The differences between the new species and related two species are summarized in Table 1 .

With the new species, the number of Trifolium in Turkey increased to 105.

Figures

FIGURE 1. Trifolium elazizense in the type locality: a, habitat; b, a plant in natural habitat; c, single plant removed from the soil; d, inflorescences with light pink flowers; e, single inflorescences with fresh pink flowers; f, infructescence.

FIGURE 2. Trifolium elazizense from dry specimen:a, infructescence and single dry flower; b, calyx removed flower; c, close up to calyx tube; d, fruiting calyx; e, callus hairs and pod; f, single pod; g, seeds; h, single seed; i, stipule.

FIGURE 3. The distribution map of T. elazizense sp. nov. (blue dot), T. longidentatum (green dot), and T. kurdistanicum (red dot).