Phylogenetic approaches resolve taxonomical confusion in Pedicularis (Orobanchaceae): Reinstatement of Pedicularis delavayi and discovering a new species Pedicularis milliana

Abstract

Morphological identification of Pedicularis depends on floral characters. However, some important characters may be lost during the process of pressing the specimen. Pedicularis delavayi was described from northwestern Yunnan, and widely adopted as a variety of P. siphonantha. Unfortunately, the name “P. siphonantha var. delavayi’ incorrectly referred to P. milliana (a new species described in this study) or P. tenuituba in some herbarium specimens and publications. Moreover, phylogenetic relationships among P. delavayi, P. siphonantha and its allies (P. milliana and P. tenuituba) were not fully resolved. In this study, we sampled 76 individuals representing 56 taxa. Of them, 10 taxa were from P. siphonantha lineage, and 11 individuals of P. delavayi represented 9 populations. These species were named as P. siphonantha group on the basis of morphological similarity. Nuclear ribosomal internal transcribed spacer (nrITS) and four chloroplast genes/regions were used for phylogenetic analyses. Phylogenetic analyses showed that the P. siphonantha group was polyphyletic: P. delavayi was sister to P. obliquigaleata in clade A; and the remaining species of P. siphonantha group were monophyletic in clade B, named as P. siphonantha lineage. In the P. siphonantha lineage, P. milliana, P. siphonantha, and P. tenuituba were well supported as monophyletic, and P. dolichosiphon was sister to P. leptosiphon. Morphologically, P. delavayi differs from species of the P. siphonantha lineage in having a long petiole (~ 50 mm) and pedicel (~ 40 mm), a ridged corolla tube, and a folded lower-lip of the corolla. Therefore, both morphological characters and phylogenetic evidence strongly supported to reinstate P. delavayi as an independent species and describe P. milliana as new species. In addition, P. neolatituba was proposed to reduce as a new synonymy of P. delavayi.

Cryptic Species Diversification of the Pedicularis siphonantha Complex (Orobanchaceae) in the Mountains of Southwest China Since the Pliocene

“…Pedicularis siphonantha D. Don from the Himalayas was the first described species. To date, at least 11 species of this complex are recognized from the western Himalayas to the Mountains of Southwest China ( Li, 1949 ; Yang et al, 1998 ; Yu et al, 2015 , 2018 ). The P. siphonantha complex was supported as monophyletic by Yu et al (2015) .…”

“…In contrast, Li (1949) considered P. delavayi as a separated species. Li (1949) and Tsoong (1963) , as well as Yang et al (1998) and other botanists, misidentified most herbarium specimens of Pedicularis tenuituba H. L. Li and Pedicularis milliana W. B. Yu et al as P. delavayi ( Yu et al, 2018 ). In addition, the infraspecific taxonomy of P. siphonantha is not fully resolved yet in the Himalaya region ( Yu et al, 2018 ).…”

“…Based on nrITS and four plastid loci ( matK , rbcL , trnH-psbA , and trnL-F ), no samples of P. delavayi cluster with other species of the P. siphonanta complex. Yu et al (2018) have reinstated P. delavayi as a separate species and discovered an undescribed species, P. milliana , which was previously misidentified as P. siphonantha var. delavayi or P. delavayi .…”

Taxonomic and nomenclatural notes on Pedicularis (Orobanchaceae): I. One new species from northwest Yunnan, China

“…Of them, about two-thirds of the species are restricted in the Hengduan Mountains, which belongs to the Mountains of Southwest China hotspot (Wang 2006, Wang and Wu 1994). Due to the previously limited accessibility of the Mountains of Southwest China before the 21 st century, several new species of Pedicularis have subsequently been discovered and described in the 2000s, owing to the construction of a road system under China’s Great Western Development Strategy (Liu and Yu 2015, Yang et al 2003, Yu et al 2010, Yu et al 2018).…”

“…According to the phylogeny of the Pedicularis species with well-represented samples from the Hengduan Mountains region, 18 taxa were not categorised as any recognised species, based on both molecular and morphological data (Yu et al 2015), which could be potential new species or new records to China. Of them, two taxa had been described as new species, P. wanghongiae M.L.Liu & W.B.Yu (Liu and Yu 2015) and P. millina W.B.Yu, D.Z.Li & H.Wang (Yu et al 2018). In this study, we described and illustrated another new species, P. multicaulis W.B.Yu, H.Wang & D.Z.Li, from the remaining 16 taxa after carefully examining morphological characters and in comparisons with herbarium specimens of the close relatives, P. taihaiensis Bonati and P. macilenta Franch.…”