﻿A new species of Veronica (Plantaginaceae) from Western Iran

﻿Abstract A new species, Veronicakurdistanica (Plantaginaceae), is described and illustrated. It grows on limestone cliffs in mountainous alpine areas of western Iran (Kurdistan province). The new species belongs to the species group of V.kurdica and is considered to be closely related to V.daranica, V.khorassanica and V.kurdica, with which the new species is compared. Molecular phylogenetic analysis of nrDNA (ITS) region confirms this relationship. Veronicakurdistanica is distinguished from the mentioned species by its glandular indumentum, length and shape of leaves and bracts, number of flowers per raceme, length and width of calyx and corolla, and size of capsules and seeds.


Introduction
Veronica L. is the largest genus within the family Plantaginaceae in its current circumscription.The genus has cosmopolitan distribution and includes ca.450 species (Albach et al. 2004;Fischer 2004).Species of Veronica have high ecological diversity and they are found in different habitats that range from arid steppes to aquatic habitats, from the sea level to high alpine regions (Albach et al. 2008).Its centers of diversity are the Eastern Mediterranean and Irano-Turanian regions, as well as in New Zealand (Albach et al. 2004).
Our knowledge of the species diversity of the genus in Iran was summarized in the "Flora Iranica" by Fischer (1981).He recognized 56 species occurring in Iran.However, several new taxa were added afterwards (Saeidi-Mehrvarz et al. 2001;Saeidi-Mehrvarz and Assadi 2003;Saeidi-Mehrvarz 2005, 2011) and the genus includes 61 species with 18 species endemic to the country according to the latest "Flora of Iran" (Saeidi-Mehrvarz 2011).At least two species have since been added to the flora of Iran (Doostmohammadi et al. 2021(Doostmohammadi et al. , 2022)).Among these, most species occur in the Zagros and Alborz (also Elburz) Mountains of Iran, which are important centers of diversity of Veronica.
Among the recent collections from the northern Zagros Mountains, we identified a small chasmophytic species of Veronica which resembles V. daranica from central Zagros.Further morphological comparisons and molecular investigations revealed that the new collection belongs to a yet unknown species, which is described below.

Materials and methods
During a scientific field survey on the western slope of the Zagros Mountains in Western Iran, the first author collected in 2015 specimens of a Veronica from Schahu Mountain in the Hawraman region, Kurdistan province.These specimens were compared with diagnostic keys reported in Floras (Fischer 1981;Saeidi-Mehrvarz 2011) and recent new records and species (Saeidi-Mehrvarz et al. 2001;Saeidi-Mehrvarz and Assadi 2003;Saeidi-Mehrvarz 2005).After careful examination with the different floras, we inspected images of type specimens from various online herbaria (BM, K, MPU, P), as well as related taxa in TUH, TARI, HKS and IRAN (herbarium acronyms according to Thiers 2016 and continuously updated).Subsequently, we measured several quantitative and qualitative morphological key traits of our specimens and related species (Table 1).
In order to determine the phylogenetic position of the new species, a phylogenetic analysis was conducted based on the nuclear ITS region.One new sequence of the ITS region of the herbarium specimen of the holotype (NO.12808 HKS) was generated using ITS1 and ITS4 primers (White et al. 1990).The new sequence was added to a sequence matrix, based on published sequences of Doostmohammadi et al. (2022).All sequences were aligned using MAFFT v. 6.0 (Katoh and Toh 2010) and edited manually using PhyDE v. 0.9971 (Müller et al. 2010).Insertions and deletions (indels) were coded as binary characters using the simple indel coding approach, as implemented in SeqState v. 1.4.1 (Müller 2005).Bayesian inference (BI) was conducted using MrBayes v.3.2.6 (Ronquist et al. 2012) under GTR+Γ+I nucleotide substitution model.Two parallel runs of four MCMC chains including three heated and one cold chain were run simultaneously for four million generations, sampling every 200 generations.After removing 25% of the sampled trees as burn-in, a 50% majority-rule consensus tree was constructed.

Results and discussion
The morphological and phylogenetic analyses indicate a close relationship between Veronica kurdistanica sp.nov., and V. daranica Saeidi & Ghahr., V. khorassanica Czernjak, and V. kurdica Benth. in DC. but ample morphological differences to suggest that V. kurdistanica is a distinct species.
Etymology.Referring to Kurdistan Province (Western Iran), where the new species was discovered.
Distribution, habitat, and phenology.The species is currently known from a few populations in Schahu mountain, Hawraman region, Kurdistan Province, western Iran.It is an Irano-Turanian phytogeographical element that grows on limestone cliffs of mountainous slopes of Schahu mountains, 2500-2950 m a. s. l. (Figs 4,5).Flowering April to May, fruiting June.Conservation status.Veronica kurdistanica is observed in a restricted area of the Avroman (Hawraman) region in the province of Kurdistan.The estimated area of occupancy is less than 50 km 2 .The species is proposed to be classified as critically endangered (CR) following the IUCN criteria (2022).
Taxonomic notes.Veronica kurdistanica belongs to Veronica subgenus Pentasepalae (Benth.)M. M. Mart.Ort., Albach & M. A. Fisch. (Fig. 6), by far the most species-rich subgenus in Iran, with many perennial, mountainous species.It has been demonstrated that this subgenus has probably originated in the Iranian plateau, with several relict and morphologically isolated species distributed at present along the Zagros and Alborz Mountains (Doostmohammadi et al. 2022).
Veronica kurdistanica belongs to the V. kurdica species group and is morphologically closest to V. daranica (Fig. 3) but occurs more than 500 km apart (Fig. 5).The group has maximum support in the phylogenetic analysis (Fig. 6), although there is no morphological character setting this group apart from related species.Members of this group are all endemic, perennial species adapted to arid conditions; they are important constituents of the alpine flora of Iran.Species delimitation is sometimes difficult among the members of V. kurdica species complex.For instance, V. daranica differs from glabrous forms of V. kurdica subsp.filicaulis (Freyn) M.A. Fisch.only by its dense, compact habit, thinner petals and some other subtle morphometric differences, but the molecular studies confirmed that it is a distinct species (Doostmohammadi et al. 2022).However, V. kurdistanica is a unique species within V. kurdica complex differing from all others by its glandular indumentum, apart from other subtler differences mentioned above.Other species are either glabrous or have an eglandular indumentum.It is not unusual in the genus to differentiate a species mainly on the basis of glandular indumentum and other subtle differences.An example is V. porphyriana Pavlov, which has often been included in V. spicata L. (sensu lato), but has been clearly differentiated based on DNA-based evidence (Khan et al. in press).In the molecular phylogenetic tree, our new species is assembled in a polytomy including V. daranica, V. khorassanica, and two subspecies of V. kurdica (Fig. 6).A comprehensive morpho-molecular study is required to delimitate further the species of this complex, both morphologically and geographically.The finding of this new species is noteworthy since it emphasizes that the Kurdistan region is an important center of diversity, despite being under-investigated.Thus, future field work may further increase the species number of the region.

Conclusion
We here provide evidence for a new species from Iran, which belongs to the V. kurdica group of Veronica subg.Pentasepalae.This finding emphasizes the need for further detailed floristic investigation of the region and further detailed phylogenetic investigations to find or clarify biogeographic patterns.

Figure 1 .
Figure 1.Veronica kurdistanica A-D habitat and habit E, F corolla and inflorescence (photos by M. Advay).

Figure 3 .
Figure 3. Veronica daranica A-C habitat and habit D corolla and inflorescence (photos by M. Doostmohammadi).

Table 1 .
The morphological differences among Veronica kurdistanica and its related taxa.