DIONYSIA JAMZADIAE (PRIMULACEAE), A NEW SPECIES FROM THE FARS PROVINCE OF IRAN

is described as new to science. It belongs in section Dionysiopsis and is similar to D. oreodoxa Bornm. but differs in, for example, its sparsely glandular hairy or almost glabrous corolla with emarginated lobes (densely non-glandular pubescent with entire lobes in D. oreodoxa ). Dionysia jamzadiae is known from two places and is quite abundant at the type locality.


Introduction
Dionysia is found from southeast Anatolia and the Zagros mountains of Iran eastwards to Afghanistan and Tadjikistan, with southern outliers in northeast Oman and northeast Balochistan, which corresponds more or less to the Flora Iranica area, part of the Irano-Turanian floristic region. The highest concentration of species we find in the Zagros. About 60 species are known at present, but it is likely that, with time, more will come to light in areas still poorly investigated.
Dionysia is a well-characterised natural (monophyletic) taxon, strongly supported as sister to the genus Evotrochis Raf. (= Primula subg. Sphondylia (Duby) Rupr.), by both morphological and molecular data (Fırat & Lidén, 2021;Mast et al., 2001). We note that if Primula L. is treated in the broad sense advocated by Mast & Reveal (2007), both the above 'satellite' genera will have to be sunk into synonymy. For the time being, however, we prefer to keep generic rank for Dionysia, in order not to forejudge a systematic overhaul of the whole Primula group.
Dionysia differs from all other taxa in the Primula group in being dwarf shrubs with woolly farina and a peculiar gummy 'bark' (Decrock, 1901). All species known are extreme cliffdwellers, often confined to vertical or even overhanging rocks. Some species in dry areas grow also on sloping ground (especially at higher altitudes), but no species can withstand having the cushions wetted for any prolonged period. Limestone is the preferred substrate of most species.
2 Dionysia jamzadiae, a new species from Fars, Iran We have, based on DNA sequences (Trift et al., 2004), a rough idea of the phylogeny of Dionysia, based on which Lidén (2007) suggested a subgeneric classification with five named sections and a few incertae sedis species. The species described here, which was discovered during an excursion in April 2018 to the province of Fars, specifically aimed at finding new species of Dionysia in poorly visited areas, belongs in the section Dionysiopsis (Pax) Melchior, which is characterised by leaves with a revolute crenate-dentate margin. The section comprises 15 species, mostly from the Zagros mountains, and most are in cultivation. Dionysia archibaldii Wendelbo, D. aretioides (Lehm.) Boiss. and D. revoluta Boiss., for example, are often found in botanical gardens or specialist amateur collections.
An updated key to the Dionysia species occurring in the Zagros mountains is included in the parallel publication by Alipour et al. (2021). Moderately dense to rather lax cushions 5-20 cm across. Stems finely glandular hairy, epidermis soon becoming reddish brown, eventually exfoliating. Marcescent leaves persistent for three seasons; leaves in distinct yearly clusters separated by more sparsely leafy internodes, or rarely almost confluent. Leaves 4-5 × 0.6-0.8 mm, bluish green, oblong, with strongly inrolled margin with 6-9 sometimes obscure crenations, beset all over with minute glandular hairs up to 0.05 mm long, or rarely almost glabrous. Farina white to yellowish, most dense on the underside of leaves and on calyx, rather particulate and giving a peculiar scabrid-sticky sensation to the touch, but clearly woolly in high magnification. Flowers sessile, single or often paired. Bracts 1 or usually 2, equalling calyx, similar to calyx lobes. Calyx 2.5-3.5 mm, divided to 4/5 into lanceolate acute lobes with a sparse pubescence of short glandular and eglandular hairs to 0.1 mm long. Corolla bright yellow with sparse glandular hairs to 0.2 mm long, or almost glabrous; tube 10-15 mm long; limb 8-13 mm broad with ovate emarginate lobes. Style in long-styled flowers not or slightly exserted; anthers of long-styled flowers and stigma of short-styled flowers situated about halfway up the tube or slightly lower. Ovary with 5-7 ovules. Capsules c.2 mm, 3-to 6-seeded. Seeds rounded to broadly ovate, 1-1.2 × 0.8-1 mm, with a thin outer soft layer of pale fatty cells.  Ecology. In crevices of limestone cliffs facing north, east and west, mostly in apparently dry situations but sometimes where water was seen oozing from the cliff.

Species description
Etymology. The species is named in honour of Ziba Jamzad, monographer of Iranian Dionysia and head of the botany research division at the Research Institute of Forests and Rangelands, Tehran. She is also editor of the Iranian Journal of Botany.
Phenology. Flowering in April (and presumably in May).

4
Dionysia jamzadiae, a new species from Fars, Iran Distribution. Known from two localities WSW of Kuh-e-Khataban, in a parallel (but lower and more disrupted) mountain chain. In the type locality it was fairly abundant, with several hundred individuals. In the second locality we found it in three spots, but with far fewer plants ( Figure 3).
Provisional IUCN category. The restricted known distribution (extent of occurrence, < 100 km 2 ; area of occupancy, < 10 km 2 ), the few localities known, and the number of known individuals possibly < 1000, suggest the category Vulnerable following IUCN (2012). We see no current threats, however, save for climate change and habitat destruction in the immediate vicinity of the quarry, and we acknowledge that there are several cliffs between the two known localities where our new species might be expected to occur. We therefore list Dionysia jamzadiae as LC (Least Concern). Dionysia jamzadiae is similar to D. oreodoxa, which differs in its densely non-glandular pubescent corolla with entire lobes. Dionysia archibaldii, although habitually similar, differs in, for example, its glabrous corolla with violet limb. Dionysia jamzadiae could possibly be confused with the widespread and variable D. revoluta, but that species has larger leaves with at least some long non-glandular hairs, many-seeded capsules (30-70 versus 3-6), small angular seeds, and usually less dense habit. In January 2020, three seeds germinated in Göteborg Botanic Garden. The first few branches are decumbent and slender with broader leaves. Along these branches numerous condensed axillary shoots are produced throughout (Figure 4), eventually transforming the habit into a cushion. This early growth behaviour is similar to that of other species of sect. Dionysiopsis, such as D. archibaldii, while being quite different from what we see in sect. Dionysia.