Tulipa toktogulica B.D.Wilson & Lazkov, 2022

Wilson, Brett, Lazkov, Georgy A., Shalpykov, Kaiyrkul T. & Brockington, Samuel F., 2022, Tulipa toktogulica (Liliaceae), a cryptic, endangered new species from the western Tien-Shan, Kyrgyzstan, Phytotaxa 566 (1), pp. 1-12 : 7-9

Tulipa toktogulica B.D.Wilson & Lazkov , sp. nov. (Fig. 3)

Type:— KYRGYZSTAN. Jalal-Abad Province : Toktogul distr. , Sussamyr Mt. R., south-east facing slope, north of Sary-Seget and Bel-Aldy villages, steppe vegetation with occasional shrubs, pastureland, 41.95854N, 73.28587E, 1670 m, 15 April 2022, Lazkov, Shalpykov, Wilson 135 (holotype: FRU; isotypes: CGE, FRU, K, LE) .

This species is most similar to Tulipa talassica in its prolonged tunic but it has broad stamens like those of T. tetraphylla and only three leaves, unlike T. tetraphylla , which usually has four or more leaves. Flowers of the new species have a faint scent, which is not present in these other Central Asian species except T. kolbintsevii Zonneveld in Zonneveld & de Groot (2012: 1294).

Perennial geophytes with ovoid bulbs, 15–25 mm in diameter, tunics light brown, prolonged, soft, papery and adpressed hairs at base and beak of inside of bulb tunic. Leaves three, greyish green with red edges near end of leaf, linear, narrow, lanceolate. Bottom two leaves similar length with basal leaf wider, upper leaf narrowest and shortest. Lower leaf 125 × 15 mm (85–193 × 10–20 mm), second leaf 122 × 8 mm (83–195 × 4–11 mm), upper leaf 99 × 5 mm (62–153 × 2–8 mm). Plant 133 mm tall (106–191 mm), stem glabrous, 102 mm long (81–155 mm), flower 31 mm long (25–36 mm). Solitary flower, slightly fragrant. Inner tepals less open than outer tepals causing it to be bucket shaped. Inner tepal approximately 35 × 14 mm, outer tepal 38 × 17 mm. Inner tepal oblong-obovate, tapering to point. Outer tepals rhombic, narrowing to point. Tepals primarily yellow, outwardly mostly red with small yellow margin and yellowish green tear-drop shaped central blotch. Stamens around 12 mm, approximately a third the length of the inner tepal. Filament 5 mm long, broad (Fig. 4), conical-ovate. Anther 7 mm long, oblong-elongate, with ridges. Anther and filament both yellow, glabrous, and of similar width. Ovary usually green but sometimes yellowish with a short sessile yellow stigma. Ovary 10 mm long, longer than filament but shorter than stamen. Seed capsule is triangular in cross section with a small middle ridge on each side and a short yellow pistil.

Etymology:— Named after the Toktogul region. We hope that naming it after this area will improve awareness of the diversity of the flora of this region and hence its conservation.

Distribution and habitat:— Known thus far from four populations occurring to the north-east of the Toktogul Reservoir. One population occurs in pastureland of the Zagyra Mountains to the south-east of Torkent (population one), several populations are known from just north of Sary-Seget and Bel-Aldy villages (populations two and three) and a fourth near where the Bordoo-Kia River joins the larger Torkent River. Specimens were collected from all these populations, but the type specimen was collected from population three, and only sterile specimens were obtained from population four. The populations found growing north of the villages of Sary-Seget and Bel-Aldy, including the type location, were located on south-east facing slopes not far from the dusty track leading up the valley at 1670 m, where there was clear evidence of some livestock grazing. The population growing in the Zagyra Mountains was found growing on relatively bare slopes in brown, clayey soil at 1077 m. There was evidence of heavy grazing in the area by cows, sheep and goats, with much of the vegetation damaged. The population found growing near the convergence of the Bordoo-Kia River with the Torkent was found only in fruit growing on a steep south-east facing slope in the valley of the Bordoo-Kia River, 1138 m elev.

Phenology:— Flowering in early to mid-April, around the same time as Tulipa tetraphylla . Lower-elevation populations of this species usually flower in early April and release seeds when populations at higher elevations are in flower.

Ecology:— In savannah-like vegetation, primarily in shrubland on stony-gravelly soil. It grows near populations of Tulipa ferganica , T. greigii and T. tetraphylla . The last two are often in flower at the same time as this species. At the type locality, it is found with Alcea nudiflora , Carex turkestanica , Euphorbia virgata , Ferula kuhistanica , Festuca valesiaca , Lathyrus pratensis , Nepeta cataria , Origanum vulgare subsp. gracile , Prangos pabularia , Rheum wittrockii , Rosa kokanica , Spiraea hypericifolia and Verbascum songaricum .

Conservation status:— Occurring at three locations consisting of four populations ( Fig. 1 ). The conservation status of a new species is often precarious ( Liu et al. 2022), and this species follows this trend. The area of occupancy (AOO = 12 km 2) and the extent of occurrence (EOO = 12 km 2) are extremely small. There is no clear estimate of how large these populations are, but they are likely below 1000 individuals based on our field observations. Crucially, the species is not known to occur in any protected area and has only recently been added to two ex-situ collections explicitly the Cambridge University Botanic Garden in the U.K. and Gareev Botanical Garden in Bishkek, Kyrgyzstan. However, it is believed to be widespread in the Toktogul area with unrecorded populations likely to be discovered soon. Tulipa toktogulica is assessed as endangered B1ab(iii) + B2ab(iii) due to the extremely small estimated AOO and EOO; it is only known from three locations and habitat quality is thought to be in decline in areas of the distribution of this species due to ongoing threats from livestock overgrazing and climate change. Focused efforts to record and monitor more populations of this species are needed, especially to assess whether it occurs in any protected areas, as well as collection of bulbs and seeds to ensure this species is protected in ex-situ collections both nationally and internationally. The status of this species may change in the future due to the discovery of new populations.

Population one was found growing in heavily grazed pastureland near the Toktogul reservoir where habitat degradation is clearly an issue (Fig. 3). Populations two, three and four were found on steep slopes at higher elevation where grazing pressure is less but still present. Several other Tulipa species occur in the same area, such as T. tetraphylla , T. greigii and T. ferganica , which are already recognised as threatened in the Kyrgyz Red Book ( Davletkeldiev 2006). Several of these are morphologically similar and could be easily mistaken for this species, so assessment of populations needs to be undertaken carefully.

Populations of these other species have been reported to be under threat from livestock overgrazing across this area. This new species is also threatened by climate change that is predicted to lead to significant loss of tulip habitat across Central Asia through changes in rainfall and temperature patterns ( Wilson et al. 2021). Finally, opportunistic collection of wild tulips has also been observed in the Toktogul area, which may lead to diminishing wild populations. However, collecting occurs only at a small scale only near settlements, and there is no established trade driving extreme specimen removal and likely only a minor threat for this species.

Figures

Figure 1a: (a) Single partition plastome tree, (b) multi-partition plastome tree, (c), multi-partition CDS tree, (d) 35S rDNA tree.