On the rediscovery of a rare root parasite Gleadovia ruborum Gamble & Prain (Orobanchaceae) from Uttarakhand, western Himalaya, India

Gleadovia ruborum Gamble & Prain (Orobanchaceae), a rare root parasite is recorded after a gap of 57 years from a new locality in Uttarakhand, western Himalaya.  A total of four individuals were located in a shady moist forest of Abies pindrow-Quercus floribunda at Surkanda hill near Mussoorie.  All the individual plants were growing on the roots of Rubus pedunculosus D. Don.  The current communication provides an updated description, habitat characteristics and host species of Gleadovia ruborum.


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The family Orobanchaceae Vent. comprising ca. 2,060 species under 90 genera are distributed across all continents except Antarctica (McNeal et al. 2013). Commonly known as the broomrape family, Orobanchaceae includes holoparasites (nonphotosynthetic) that depend on their hosts and hemiparasites (photosynthetic), most of which were earlier kept in Scrophulariaceae. Pedicularis L. with ca. During a recent floristic exploration (June-July 2020) in and around Surkanda in the outer Himalayan range of Uttarakhand, western Himalaya, an interesting plant species of family Orobanchaceae was observed. Detailed study of the characters observed in the field, scrutiny of literature (Gamble & Prain 1900;Issar 1966;Wu & Raven 1998;Agarwal 2017;Roy 2017) and examination of online herbarium specimens at Kew (J.S. Gamble, 26949K! (K000999865 and K000999866)) and DD (Osmaston, 23093;Charlton Thomas, 20794) revealed that the taxon is a rare root parasite, Gleadovia ruborum, a species previously known only from three localities ( Figure 1). The species was originally collected by M.F. Gleadov in 1898 and later described by J.S. Gamble and D. Prain in 1900 from Bodyar (Budher) near Chakrata, Uttarakhand. The species was recollected from the same locality by Osmaston in 1900. Later, it was also collected by Charlton Thomas in 1951 from Balate valley in eastern Almora (now in Pithoragarh district), Kumaon and Ramesh Bedi in 1964(GKV 1234) from Yamuna Forest Division, Garhwal (Issar 1966. The plant specimen of G. ruborum along with roots of the host, Rubus pedunculosus has been preserved (wet specimen) following standard methods and deposited at the herbarium of the Wildlife Institute of India, Dehradun (WII). Detailed information on the distribution range, J TT known host, habitat, elevation range and phenology of Gleadovia species are provided in Table 1.
Fleshy, root-parasitic herb 10-18 cm high. Rootstock bulbous and swollen at the point of attachment with the host root. Stem largely sub-terranean, with ovate scales; lower scales rounded, upper oblong and sometimes bifid. Flowers in dense corymbose or paniculate inflorescences at the end of stem. Pedicel stout ca. 0.8cm long. Bracts solitary, ca. 1.5 cm long, sheathing, rounded; bracteoles two, 1.5-2.5 cm long, spatulate, acute, concave. Calyx 2.5-3 cm long, light red, tubular, somewhat inflated, equally five-lobed, lobes rounded, divided to less than half the tube length. Corolla up to 5 cm long, white at the base, reddish towards the apex, with dark longitudinal veins; tube much longer than the calyx, slightly curved, two-lipped; upper lip of two connate, rounded, lobes; lower lip of three narrow, acute lobes. Stamens 4; filaments bent at point of insertion; anthers spurred, connectives produced beyond the anther lobes, 3-fid at the apex. Ovary one-celled, ovate. Style shorter than the filaments; stigma of two fleshy, semi-orbicular lobes depressed in the centre; placenta 2 pairs, free below and above, confluent in the middle; ovules numerous. Seeds numerous, minute.
Etymology: Genus 'Gleadovia' is dedicated to M.F. Gleadov who was first to discover it in 1898 and 'ruborum' refers to red corolla with darker veins. Distribution range, host, and habitat: G. ruborum was first recorded in shady forest at Bodyar or Budher in Jaunsar, Dehradun district at 2,500 m above mean sea level by M.F. Gleadov in 1898 (Gamble & Prain 1900). Interestingly, it shows disjunct distribution as it has also been reported in northern Guangxi, Hubei, western Hunan and southwestern Yunnan areas of China (Hu 1939; eflora China). Notably, it has not been recorded anywhere else from India and China (Agarwal 2017). Issar (1966), Roy (2017), and Osmaston (1900) had recorded Glaedovia ruborum on the roots of Rubus pedunculosus (R. niveus Wall. ex. Hook; Agarwal 2017). Agarwal (2017) studied the flora of Chakrata hills in detail but he could not locate populations of G. ruborum in its type locality despite best efforts. In Surkanda (the new locality), all the four individuals were recorded on the roots of Rubus pedunculosus in Abies pindrow-Quercus floribunda forest at 2,450 m on northern slopes. The common species recorded in the vicinity (314 m 2 ) of Gleadovia were Quercus floribunda, Abies pindrow, Viburnum cotinifolium, Daphne papyracea, Salix denticulata, Rosa macrophylla, Hypericum oblongifolium, Senecio rufinervis, Roscoea purpurea, and Geranium wallichianum.
Conservation status: G. ruborum has been assessed as 'rare' and 'extremely rare' by Issar (1966) and Agarwal (2017), respectively. The IUCN conservation status of this species is yet to be assessed.
In the current communication, we report a new locality of G. ruborum at 2,450 m in Surkanda near Mussoorie of Tehri Garhwal district, Uttarakhand. The present collection marks the rediscovery of the species after a gap of 57 years from a new locality in the Uttarakhand, western Himalaya. The new location is approximately 60km from the type locality. Intensive surveys in the right season, in temperate and sub-alpine shady moist forests with a dense undergrowth of Rubus pedunculosus may yield more distributional records and better understanding of its distributional range.

Roy, D.K. (2017). Lectotypification of the name Gleadoviaruborum
Gamble & Prain (Orobanchaceae). Phytotaxa 323 (2) www.threatenedtaxa.org The Journal of Threatened Taxa (JoTT) is dedicated to building evidence for conservation globally by publishing peer-reviewed articles online every month at a reasonably rapid rate at www.threatenedtaxa.org. All articles published in JoTT are registered under Creative Commons Attribution 4.0 International License unless otherwise mentioned. JoTT allows allows unrestricted use, reproduction, and distribution of articles in any medium by providing adequate credit to the author(s) and the source of publication.