Indurgia Speta

Martínez-Azorín, Mario, Crespo, Manuel B., Alonso-Vargas, María Ángeles, Pinter, Michael, Crouch, Neil R., Dold, Anthony P., Mucina, Ladislav, Pfosser, Martin & Wetschnig, Wolfgang, 2023, A generic monograph of the Hyacinthaceae subfamily Urgineoideae, Phytotaxa 610 (1), pp. 1-143 : 51-56

9. Indurgia Speta in Stapfia 75: 169 (2001)

( Figs 27–28 ).

Typus generis:— I. indica (Roxb.) Speta (holotype).

≡ Drimia sect. Indurgia (Speta) J.C.Manning & Lekhak in S. African J. Bot. 123: 67 (2019). Typus sectionis:— I. indica (Roxb.) Speta ≡ Drimia indica (Roxb.) Kunth (holotype).

Description:—Bulbous geophyte. Bulb hypogeal ovoid to globose, 2–9 cm in diam., bulb scales usually compact, white. Roots thickened and branched. Leaves 3–15 per bulb, 13–50 × 0.1‒5.5 cm, linear to lanceolate, canaliculated, glabrous, synanthous or hysteranthous. Inflorescence a lax or dense raceme, usually elongated and multiflowered, 10‒ 90 cm long, with 4‒50 flowers; peduncle 10‒160 cm long, terete, erect, smooth and glabrous; pedicels 0.4‒10 cm long, from suberect to recurved and arquing downwards. Bracts deltoid, caducous, lowermost with short spur; bracteoles absent. Flowers stellate, nocturnal and nodding or diurnal and erect-patent. Tepals 6, biseriate, 5‒18 mm long, oblong to oblong-lanceolate, whitish, yellowish or brownish, with darker midrib, free or shortly fused, spreading to recurved. Stamens 6, suberect to spreading, not connivent to style; filaments subulate-filiform, 3–15 mm long, smooth, adnate to tepals at base; anthers dorsifixed, dehiscing by longitudinal slits along their whole length, yellowish. Ovary ovoid-ellipsoid, 2.0– 7.5 mm long, trigonous, pale green to yellowish, well differentiated from style. Style subclavate, usually thickened, as long as or only slightly longer than the ovary. Stigma trigonous, truncate, papillose. Capsule ellipsoidoblong, 8‒26 mm long, valves apiculate, completely dehiscing from base, tepals cohering and inrolled above ovary after anthesis, circumcissile from base and persisting as a cap at the top of the developing capsules. Seeds elliptic to suborbicular, 4‒12 mm long, black, glossy, flattened with prominent central embryo and wide, flat wings.

Number of species and distribution:— Indurgia currently includes ten species, occurring from India and Sri Lanka to Thailand ( Fig. 8 ) (cf. Yadav et al. 2019), hence it is almost restricted to the Indian and Indochinese Regions (sensu Takhtajan 1986), although some species also reach the eastern regions of the Omano-Sindian Subregion ( Martínez-Azorín et al. 2023a), shared with Vera-duthiea , which is present in Oman ( Patzelt et al. 2021). For further information on Indurgia species see Yadav et al. (2019) and Karuppusamy & Ravichandran (2021), among others.

Karyology:—2n=20 ( Stedje & Nordal 1987, Yadav & Dixit 1990, as Urginea congesta Wight ; Raghavan & Venkatasubban 1940, Boraiah & Khaleel 1970, Naik 1976, Jha 1989, as Urginea indica Kunth ; Kamble & Ansari 1976, Yadav & Dixit 1990, as Urginea polyantha Blatt. ; Yadav & Dixit 1990, as Urginea razii (M.Y.Ansari) Deb & Dasgupta ; Boraiah & Khaleel 1970, as Urginea govindappae Boraiah & Fathima ; Boraiah & Fathima 1972, as Urginea govindappensis Boraiah & Fathima ); 2n=20, 30 ( Raghavan & Venkatasubban 1940, as Urginea polyphylla Hook.f. ); 2n=20, 40, 60 ( Jha & Sen 1983, as Urginea indica Kunth ); 2n=40 ( Naik 1973, Naik 1976, Dixit & Yadav 1989, as Urginea coromandeliana Hook.f. ).

History, diagnostic characters, and taxonomic relationships:— Roxburgh (1832) described Scilla coromandeliana Roxburg (1832: 147) and S. indica Roxburg (1832: 147) from India. Further taxa were described by Kunth (1843), Wight (1853) and Hooker (1892) from the same region and later placed in Urginea . Speta (1998b) transferred the Indian species to Thuranthos and soon after Speta (2001) described Indurgia to include the Indian members of Urgineoideae based on the phylogenetic analyses of Pfosser & Speta (2001). The revision of Urgineoideae in Southern Africa by Manning & Goldblatt (2018) includes Indurgia and Vera-duthiea (genera originally described to be restricted to southeastern Asia and to Central and northwestern Africa, respectively) in synonymy of their Drimia sect. Thuranthos . They further included the Southern African species D. hesperantha (= Urginea revoluta ), D. vespertina Manning & Goldblatt (2018: 65) , D. macrantha ( Baker 1873b: 280) Baker (1892: 7) , and D. basutica ( Phillips 1917: 306) Manning & Goldblatt (2018: 68) , together with D. indica Roxburg (1832: 147) Jessop (1977: 272) from India, so conceiving their section in a very wide sense. Manning & Goldblatt (2018) characterised the section by the nocturnal flowers with reflexed tepals, but acknowledged that it was probably not monophyletic. This was already shown by the phylogenetic works of Pfosser & Speta (2001, 2004), with Thuranthos , Indurgia , and Vera-duthiea (as Duthiea Speta , nom. illeg.) representing independent and distant well-supported clades.

Yadav et al. (2019) presented a detailed taxonomic revision of the Indian species of Drimia sensu lato accepting nine species that were placed in their new D. sect. Indurgia ( Speta 2001: 169) J.C.Manning & Lekhak in Yadav et al. (2019: 67) to segregate the southeastern Asian members of Urgineoideae , and corroborated the exclusion of D. indica from Southern Africa, earlier shown by Martínez-Azorín et al. (2018b, 2019a). The new section comprised taxa having hysteranthous or synanthous leaves, lax or dense racemes, deltoid, caducous bracts with the lower ones short-spurred, a lack of bracteoles, nocturnal and nodding flowers or sometimes diurnal and spreading, tepals almost free or shortly connate basally, recurved or spreading, and filaments adnate to the base of the tepals. These taxa were divided into two distinct pollination syndrome groups: (i) the Drimia indica group for D. coromandeliana (Roxburg 1832: 146) Lekhak & P.B.Yadav in Yadav et al. (2016: 256), D. govindappae ( Boraiah & Fathima 1972: 128) Lekhak & P.B.Yadav in Bhat & Wani (2017: 145), D. indica , and D. nagarjunae ( Hemadri & Swahari 1982: 105) Kumar (1984: 962) , an assemblage of night-flowering species with metareticulated pollen grains; and (ii) the D. wightii Lakshminarasimhan (2003: 507) group for D. polyantha ( Blatter & McCann 1928: 735) Stearn (1978: 208) , D. raogibikei ( Hemadri 2006a: 386) Hemadri (2006b: 224) , D. razii Ansari (1981: 572) , and D. wightii , to include the day-flowering species with microreticulated pollen grains. Species in these two groups are isolated by their different flowering phenology, and natural hybrids are unknown ( Patil & Yadav 1992 −1993).

Preliminary phylogenetic analyses of Indian members of Urgineoideae by Pfosser & Speta (2001, 2004) and Pfosser et al. (2012) incorporate up to six samples of Indurgia and form a perfectly supported clade, which is included in a collapsed clade that includes Ebertia , Vera-duthiea (as Duthiea , nom. illeg.), and Urginea s.str., as well supported subclades. Saha & Jha (2019) extended the phylogenetic work in Indurgia , combining plastid and nuclear DNA regions of twelve samples covering seven species from India, which formed a strongly supported clade. The studied samples belong to both day- and night-blooming species with synanthous and hysteranthous leaves. The phylogenetic results show two subclades based on the nuclear ITS region: subclade I comprising D. indica , D. polyantha , and D. coromandeliana , and subclade II including D. nagarjunae , D. govindappae , D. wighttii , and D. razii . Both subclades merge day- and night-flowering species as reported by Yadav et al. (2019), indicative that divergence in phenology (and related pollination syndromes) has arisen more than once in Indurgia , so limiting the validity of taxonomic inferences that can be drawn.

The phylogenetic analyses of Martínez-Azorín et al. (2023a) include six samples of Indurgia from India and Thailand and agree with previous works showing a well supported clade to combine all studied samples of Urgineoideae from that region. Therefore, we here accept Indurgia at genus rank based on a syndrome of morphological characters, such as, linear-lanceolate, channelled leaves, deltoid, caducous and shortly spurred bracts, a lack of bracteoles, tepals leathery and almost free to shortly connate, spreading to recurved, filaments adnate to the base of the tepals, erect to suberect, straight, subulate filiform, anthers dorsifixed, styles erect, usually thickened, subclavate, truncate, stigma trigonous, capsule with apiculate valves, and seeds ellipsoid with a prominent central embryo and flattened, winged margins, arranged vertically in one or two rows per locule, decreasing in size from the distal to the proximal side. Further, the restricted distribution of Indurgia to southwestern Asia and its isolated evolutionary status also supports its acceptance at genus rank. Indurgia is sister to Urginea and Spirophyllos , which points to a close evolutionary relationship accounted for by colonisation in the Northern Hemisphere following the arrival of an urgineoid migrant from Southern Africa. Further phylogenetic studies, in combination with morphology, are necessary to evaluate possible infrageneric classification.

Accepted species and required new combinations:—

Indurgia congesta (Wight) Speta in Stapfia 75: 170 (2001) ≡ Urginea congesta Wight in Icon. Pl. Ind. Orient. 6: 28, t. 2064 (left hand figure) (1853), basionym ≡ Drimia congesta (Wight) Stearn in Ann. Mus. Goulandris 4: 208 (1978), nom. illeg., [non D. congesta Bullock in Bull. Misc. Inform. Kew 1932(10): 504 (1932)] ≡ Drimia wightii Lakshmin. in Kew Bull. 58(2): 507 (2003) ≡ Thuranthos congestus (Wight) Speta in Phyton (Horn, Austria) 38: 81 (1998) ( Figs 2.12 , 27.2 ). Type:— INDIA. Cadungalungoo, without date, R. Wight s.n. (K000802725! lecto. designated by Yadav et al. in Phytotaxa 289: 258. 2016).

Indurgia coromandeliana (Roxb.) Speta ex Mart. -Azorín, M.B.Crespo & M.Á.Alonso comb. nov. ≡ Scilla coromandeliana Roxb., Fl. Ind. 2: 147 (1832), basionym ≡ Urginea coromandeliana (Roxb.) Hook.f., Fl. Brit. India 6(18): 347 (1892), nom. illeg., [non U. coromandeliana Wight in Icon. Pl. Ind. Orient. [Wight] 6: t. 2064 (1853)] ≡ Thuranthos coromandeliana (Roxb.) Speta in Phyton (Horn, Austria) 38(1): 84 (1998) ≡ Drimia coromandeliana (Roxb.) Lekhak & P.B.Yadav in Phytotaxa 289(3): 256 (2016) ≡ Indurgia coromandeliana (Roxb.) Speta in Stapfia 75: 170 (2001), nom. inval. (without basionym page) ( Fig. 27.2 ). Type:— INDIA. Sand hills on the coast of Coromandel, unpublished illustration for Roxburgh, Fl. Ind. 2, t.1821 (K lecto. designated by Yadav et al. in Phytotaxa 289: 256. 2016).

Indurgia govindappae (A.Boraiah & Fathima) Speta in Stapfia 75: 170 (2001) ≡ Urginea govindappae A.Boraiah & Fathima in Bull. Bot. Surv. India 12(1–4): 128 (1972), basionym ≡ Urginea govindappensis A.Boraiah & Fathima in Proc. Indian Sci. Congr. Assoc. 59(3): 359 (1972), nom. inval. [without Latin descr.] ≡ Thuranthos govindappae (A.Boraiah & Fathima) Speta in Phyton (Horn, Austria) 38(1): 84 (1998) ≡ Drimia govindappae (A.Boraiah & Fathima) Lekhak & P.B.Yadav in Bhat & Wani, Chromosome Structure and Aberrations: 145 (2017). Type:— INDIA. Karnataka Lal Baugh [Karnataka Lalbagh Botanical Garden], Bangalore [Bengaluru], 17 May 1968, G. Boraiah & T. Fathima 601A (CAL holo.).

Indurgia indica (Roxb.) Speta in Stapfia 75: 170 (2001) ≡ Scilla indica Roxb., Fl. Ind. 2: 147 (1832), basionym ≡ Urginea indica (Roxb.) Kunth, Enum. Pl. 4: 333 (1843) ≡ Drimia indica (Roxb.) Jessop in J. S. African Bot. 43(4): 272 (1977) ≡ Thuranthos indicus (Roxb.) Speta in Phyton (Horn, Austria) 38: 84 (1998) ( Figs 2.13 , 27.1 ). Type:— INDIA. Coromandelia (K000802723! neotype designated as “type” by Stedje in Nordic J. Bot. 7(6): 664. 1987). Note:—Some authors accept that a lectotype was designated by Deb & Dasgupta (1974: 118) on the plate num. 1396 ( Scilla indica ) conserved at CAL (see Yadav et al. 2019: 72). However, Deb & Dasgupta (1974) explicitly cited that they did not see the type material and simply added that the cited plate “fully agrees with Roxburgh’s description”. We do not consider it as an effective lectotypification, and conversely accept (neo)typification by Stedje (1987) on the material K000802723! (which she cited as “type”).

= Urginea wightiana Hook.f., Fl. Brit. India 6(18): 347 (1892) ≡ Thuranthos wightianus (Hook.f.) Speta in Phyton (Horn, Austria) 38: 84 (1998) ≡ Indurgia wightiana (Hook.f.) Speta in Stapfia 75: 170 (2001). Type:— INDIA. Coimbatore, March 1846, Wight s.n. (K000802724! holo.).

Indurgia jeevae (Karupp. & V.Ravich.) Mart.- Azorín, M.B.Crespo & M.Á.Alonso comb. nov. ≡ Drimia jeevae Karupp. & V.Ravich. in Gardens’ Bulletin Singapore 73(1): 210 (2021), basionym. Type:— INDIA. Tamil Nadu, Kanyakumari District, Alamparai Hills , elev. 600 m, 9 March 2012, S. Karuppusamy & V. Ravichandran 874 (MH holo.; Sri Ganesan Herbarium iso.).

Indurgia nagarjunae (Hemadri & Swahari) Speta in Stapfia 75: 170 (2001) ≡ Urginea nagarjunae Hemadri & Swahari in Ancient Sci. Life 2: 105 (1982), basionym ≡ Drimia nagarjunae (Hemadri & Swahari) An.Kumar in J. Econ. Tax. Bot. 5(4): 962 (1984) ≡ Thuranthos nagarjunae (Hemadri & Swahari) Speta in Phyton (Horn, Austria) 38: 84 (1998). Type:— INDIA. Andhra Pradesh, Krishna district, Vijayawada, 5 May 1980, Hemadri & Swahari 3001A (CAL holo.; AYUSH, VIJAYAWADA, BSI, K000802727!, BLAT, MH iso.).

Indurgia polyantha (Blatt. & McCann) Speta in Stapfia 75: 170 (2001) ≡ Urginea polyantha Blatt. & McCann in J. Bomb. Nat. Hist. Soc. 32: 735 (1928), basionym ≡ Drimia polyantha (Blatt. & McCann) Stearn in Ann. Mus. Goulandris 4: 208 (1978) ≡ Drimia polyantha (Blatt. & McCann) Ansari & Sundararagh. in J. Bombay Nat. Hist. Soc. 77(1): 174 (1980), nom. superfl. ≡ Thuranthos polyanthus (Blatt. & McCann) Speta in Phyton (Horn, Austria) 38: 84 (1998) ( Fig. 28 ). Type:— INDIA. Maharashtra, Panchgani, March–April 1926, Blatter & McCann 101a (BLAT lecto. designated as “ type ” by Deb & Dasgupta 1974: 122).

Indurgia raogibikei (Hemadri) Mart.-Azorín, M.B.Crespo, M.Pinter & Wetschnig in Phytotaxa 397: 294 (2019) ≡ Urginea raogibikei Hemadri in Med. Fl. of Pragati Resorts.: 386 (2006a), basionym ≡ Drimia raogibikei (Hemadri) Hemadri in A Treatise on Tribal Medicine: 224 (2006b). Type:— INDIA. Andhra Pradesh, Nellore district, Bhata–Udayagiri, 6 June 2006, Hemadri 2A (CAL holo.; BSI, K iso.).

Indurgia razii (Ansari) Speta in Stapfia 75: 170 (2001) ≡ Drimia razii Ansari in J. Bombay Nat. Hist. Soc. 78(3): 572 (1981), basionym ≡ Urginea razii (Ansari) Deb & Dasgupta in J. Bombay Nat. Hist. Soc. 84(2): 412 (1988) (as “rajii”) ≡ Thuranthos razii (Ansari) Speta in Phyton (Horn, Austria) 38: 84 (1998). Type:— INDIA. Maharashtra, Pune district, Dive Ghat, near Zendewadi, 19 April 2015, P.B. Yadav & M.M. Lekhak 18 (CAL neo. designated by Yadav et al. in Phytotaxa 289: 256. 2016).

Indurgia rupicola (Trimen) Mart.-Azorín, M.B.Crespo & M.Á.Alonso comb. nov. ≡ Urginea congesta Wight var. rupicola Trimen in J. Bot. 27: 167 (1889), basionym ≡ Drimia rupicola (Trimen) Dassan. in M.D. Dassanayake & W.D. Clayton (eds), Revised Handb. Fl. Ceylon 14: 220 (2000). Type:— SRI LANKA. Chinks of arid flat rocks at Dambulla, on the lower part of the ascent to the Temples, July 1887, Trimen s.n. (K000802726! holo.).

Figures

FIGURE 2. Seed morphology in Urgineoideae. 1. Drimia neriniformis Baker; 2. Drimia robusta Baker; 3. Fusifilum capitatum (Hook.) Speta; 4. Fusifilum montanum (A.P.Dold & E.Brink) A.P.Dold et al.; 5. Fusifilum physodes (Jacq.) Speta; 6. Geschollia anomala (Baker) Speta; 7. Geschollia brachyandra Mart.-Azorín et al.; 8. Geschollia calcarata (Baker) Mart.-Azorín et al.; 9. Geschollia globuligera Mart.- Azorín et al.; 10. Geschollia occultans (G.Will.) Mart.-Azorín et al.; 11. Geschollia prolifera Mart.-Azorín et al.; 12. Indurgia congesta (Wight) Speta; 13. Indurgia indica (Roxb.) Speta; 14. Iosanthus amboensis (Baker) Mart.-Azorín et al.; 15. Iosanthus macrostigma Mart.-Azorín et al.; 16. Iosanthus toxicarius (C.Archer & R.H.Archer) Mart.-Azorín et al.; 17. Litanthus pusillus Harv.; 18. Litanthus stenocarpus (J.C.Manning & J.M.J.Deacon) Mart.-Azorín et al.; 19. Mucinaea nana (Snijman) M.Pinter et al.; 20. Rhadamanthopsis haworthioides (Baker) Mart.-Azorín et al. All to the same scale in mm.

FIGURE 8. Approximate distribution ranges of accepted genera in Urgineoideae.

FIGURE 27. Species of Indurgia Speta. 1. Indurgia indica (Roxb.) Speta from Wigth (1853: t. 2063, as Urginea indica (Roxb.) Kunth); 2. Indurgia congesta (Wight) Speta (left side) and Indurgia coromandeliana (Roxb.) Speta (right side) from Wigth (1853: t. 2064, as Urginea congesta Wight and Urginea coromandeliana (Roxb.) Hook.f. respectively).

FIGURE 28. Indurgia polyantha (Blatt. & McCann) Speta (Photographs from upper row by S. Dutta).