taxonID	type	description	language	source
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	diagnosis	The new species is most morphologically similar to Typhonium varians Hett. & Sookchaloem in Hetterscheid et al. (2001: 51) in variant shape of leaves, triangular ovate spathe limb and general florescence structure but differs from the latter in having plain green (vs. variegated) leaves, underground (vs. above ground) flowering spathe tube, abaxially reddish purple to greenish grey, brownish mottled and ascending (vs. dark green flushed with dirty brown and horizontal) spathe limb, erect (vs. ascending) spadix, bright yellow staminodes curved downwards at their tips only (vs. pale yellow staminodes curved upwards or downwards over their entire length), ovoid (vs. spathulate to pyriform) fruits and generally smaller floral parts (3.5 – 4.5 vs. 8.0 – 13.5 cm long spadix, 3.5 – 5.0 × 2.0 – 2.5 vs. 7 – 14 × 4.0 – 7.5 cm spathe limb, 2.0 – 3.5 × 0.4 – 0.5 vs. 4.5 – 9.0 × 0.6 – 1.0 cm spadix appendix).	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	materials_examined	Type: — VIETNAM. Ba Ria - Vung Tau Province: Binh Chau - Phuoc Buu Nature Reserve, about 107 o 30 ’ 52 ’’ E, 10 o 36 ’ 17 ’’ N, 30 m elevation, 05 August 2015, Le Van Son, Nguyen Phi Nga & Van Hong Thien H. T. Van 115 (holotype SGN!, isotypes PHH!, VNMN!).	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	description	Herb seasonally dormant; rhizome tuberous, subglobose to ellipsoid, underground, 1.0 – 1.5 cm long, ca. 1 cm in diameter, producing many thick roots. Leaves 4 – 5. Petiole smooth, slender, 7 – 15 cm long, 2 – 3 mm in diameter, white to grey with brownish mottled at base, green towards the apex. Leaf blades entire or pedatisect, green above, pale green beneath; entire blades linear, deltoid to lanceolate, 6 – 10 cm long, 2 – 8 cm wide, with acuminate to obtuse apex; pedatisect blades with 3 to 5 linear to lanceolate segments (up to 15 cm long, 2.0 – 4.5 cm wide). Inflorescence, solitary (rarely 2), slightly foetid smelling; peduncle underground, elongated in fruiting, white, 1.5 – 2.0 cm long, ca. 3 – 5 mm in diameter; spathe 4.5 – 6.0 cm long; spathe tube underground, separated from the limb by a constriction, ovoid or ellipsoid, 1.3 – 1.7 cm long, 9 – 10 mm wide, outside white with brownish dots, inside white to pale pink; spathe limb triangular ovate, 3.5 – 5.0 cm long, 2.0 – 2.5 cm wide, outside reddish purple to greenish grey, brownish mottled, inside dark purple to reddish purple; spadix little shorter than spathe, sessile, erect; female zone conical, 2 – 3 mm high, ca. 5 mm in diameter at base, with 6 – 7 rows of crowded pistils; ovary obovoid or slightly cylindrical, 1 mm high, 0.7 mm in diameter, translucent white with brownish dots at apex, 1 - locular, with 1 basal ovule; style very short; stigma disciform, thick, 0.6 mm in diameter, 0.3 mm high, blackish purple to pink, papillate; sterile zone contiguously female zone, 8 – 10 mm long, lower part covered with 3 – 4 rows of staminodes, upper part naked; staminodes bright yellow, subulate, 2 – 3 mm long, ca. 0.5 mm in diameter, ascending forming an obtuse angle with the spadix axis, slightly curved downward, weakly papillose; male zone cylindrical, 6 – 10 mm long, 3.5 – 5.0 mm in diameter; stamens densely arranged, pale yellow to pink; thecae opening by elongate slit; appendix shortly stipitate, outside brownish purple to reddish, inside light yellow, elongate conical, 2.0 – 3.5 cm long, 4 – 5 mm in diameter at base, with acute apex and truncate base. Infructescence obconical with spathe tube remaining and above the ground; fruits obconical, pinkish white with pale pinkish spots, 4 – 7 mm long, 2 – 3 mm wide, 1 - seeded; seed obovate (or having constriction), at first creamy white, light brown when mature, 3.0 – 3.5 mm long, 2.0 – 2.5 mm wide.	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	etymology	Etymology: — The species is named after Vietnam, the country of origin.	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	vernacular_names	Vietnamese name: — Bán h ạ Vi ệt Nam.	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	biology_ecology	Ecology: — The new species grows in clumps on open sandy soil in sparse dipterocarp-dominated forests. Different leaf forms were found in plant individuals or clumps. Flowering was seen in May to June and fruiting in July to August. The plant becomes dormant in November to April next year.	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	materials_examined	Additional specimen examined (paratype): — VIETNAM. Dak Lak Province: Yok Don National Park, 01 October 2015, Nguyen Le Xuan Bach & Van Hong Thien H. T. Van 126 (SGN!).	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	distribution	Distribution: — Ba Ria - Vung Tau Province and Dak Lak Province, southern Vietnam.	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	conservation	Proposed IUCN conservation status: — Data Deficient (DD) (IUCN Standards and Petitions Subcommittee 2017). Typhonium vietnamense has so far been found in two protected areas (Binh Chau - Phuoc Buu Nature Reserve, Ba Ria - Vung Tau Province and Yok Don National Park, Dak Lak Province) in southern Vietnam. Although its habitat in Binh Chau - Phuoc Buu Nature Reserve is planned to be converted into a resort in the near future, the species is likely to occur in adjacent similar sparse dipterocarp-dominated forests in Cambodia. Further survey work is necessary before a definitive conservation assessment can be made.	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFEFFE3FF137DDAFAFD42E9.taxon	discussion	Notes: — The new species is morphologically closest to Typhonium varians but they have a number of differences as expressed in the diagnosis. Several other Typhonium species share with T. vietnamense a similar spadix structure, especially in the shape of spadix appendix and staminodes, but these are easily distinguishable: T. conchiforme Hetterscheid & Galloway (2006: 80) by deeply sagittate leaf blades, deeply cymbiform, strongly concave spathe limb and off-white or pale yellow staminodes; T. sagittariifolium Gagnepain (1942 b: 11) by deeply trilobed sagittate leaf blades, erect elongate triangular spathe limb, longer spadix appendix (8 mm), and longer (3 – 5 mm) and recurved staminodes; and Typhonium viridispathum Galloway & Sinhabaedya (2012: 61) by bright green spathe with elongate triangular limb, off-white spadix appendix, basally white and apically pale green ovaries and white staminodes.	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFDFFE5FF137C9CFBA04171.taxon	materials_examined	Type: — THAILAND. Type: from a plant cultivated by A. Galloway (orig. coll.: Khon Kaen Province, in sandy soil in open sunny areas, S. Charoenwong), 4 July 2014, Galloway AGA- 2513 - 01 - T (holotype QBG, spirit collection).	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFDFFE5FF137C9CFBA04171.taxon	description	Herb seasonally dormant; rhizome cylindrical, underground, 1.5 – 3.0 cm high, 2.0 – 2.5 cm in diameter, producing many filiform roots. Leaves 3 – 5. Petiole smooth, slender, 6 – 12 cm, 2 – 3 mm in diameter, green to pale grey, smooth. Leaf blade variable, entire to 3 - lobed; entire blade 7 – 14 cm long, 1 – 4 cm wide, green above, pale green beneath, base cordate, apex acute, midrib slightly impressed adaxially and prominent abaxially, lateral veins 2 – 3, collective veins at 1 – 2 mm from margin; lobes linear-lanceolate to ovate or elliptic, sometimes petiolulate, apex acute to acuminate, central lobe 3 – 16 cm long, 0.5 – 2.0 cm wide, lateral lobes 3 – 6 cm long, 0.5 – 1.0 cm wide. Inflorescence 1 – 2, strongly foetid smelling; peduncle subterranean, white, slender, 3 – 4 cm long, ca. 5 mm in diameter; spathe 8 – 14 cm long, basal part subterranean, separated from the limb by a constriction, ovoid or ellipsoid, 1.5 – 1.8 cm long, 0.8 – 1.2 cm wide, white on both sides, sometimes purple tinged externally; spathe limb linear-lanceolate, 11 – 13 cm long, ca. 1 cm in diameter at base, curved downward at anthesis, outside grey to dark purple, brownish mottled, inside dark violet, with or without white longitudinal stripes at base; spadix longer than spathe, 17 – 20 cm long, stipitate, stipe 1.5 – 2.0 mm long; female zone hemispherical to conical, 1.5 – 2.5 mm high, 2.5 – 4.0 mm in diameter at base, with 4 – 5 rows of crowded pistils; ovary cylindrical to obconical, 0.5 – 0.7 mm high, 0.5 – 0.6 mm in diameter, light yellow, 1 - locular, with 1 basal ovule; stigma sessile, 0.3 mm in diameter, concave, sometimes papillose at center, pale yellow with purple around, many pale reddish mottles surrounded stigma; sterile interstice above female zone, about 1.5 cm long, lower part 1 – 2 mm from female zone covered with 2 – 3 rows of staminodes, upper and lower part naked; staminodes loosely arranged, lightly brown, fusiform, 3 – 5 mm long, 0.5 – 1.0 mm in diameter, ascending, apex obtuse to subacute; male zone cylindrical, 3 – 4 mm long, 4 mm in diameter; stamens densely arranged, translucent; thecae light yellow, opening by elongate slit, pollen orange to yellow; appendix stipitate, light yellow to greenish brown, filiform, 15 – 18 cm, 2 – 3 mm in diameter at base, base slightly swollen, stipe ca. 2 mm long, acute, white. Infructescence obconical with spathe tube persistent; fruits obconical, apex truncate or concave, cream white, pinkish white with pale reddish spots, sometimes apically green with purple dots, 3 – 4 mm long, 1.5 – 2.5 mm wide, 1 - seeded; seed obovate cream white or pale pinkish, 2.5 – 3.5 mm long, 1.5 – 2.0 mm wide.	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFDFFE5FF137C9CFBA04171.taxon	materials_examined	Specimens studied: — VIETNAM. Ho Chi Minh City, 29 May 2017, Thong Nhat Palace, Luu Hong Truong H. T. Van 83 C (SGN!); Long An Province, Duc Hoa District, 06 Aug 2015, Nguyen Phi Nga H. T. Van 83 B (SGN!, PHH!); Ba Ria - Vung Tau Province, Binh Chau - Phuoc Buu Nature Reserve, about 107 o 30 ’ 27 ’’ E, 10 o 33 ’ 01 ’’ N, 32 m elevation, 06 June 2015, Van Hong Thien H. T. Van 83 A (SGN!, PHH!).	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
03A86A70FFFDFFE5FF137C9CFBA04171.taxon	discussion	Notes: — Our collections show that the populations from inland (i. e., Ho Chi Minh City and Long An Province) match well the protologue of T. khonkaenensis but that from the coastal Ba Ria - Vung Tau Province is quite distinction in having highly variable shapes of leaf blade (such as triangular, cordate-sagittate, linear-lanceolate or trifoliolate). The leaf blade of Typhonium is often known to vary within one species and a genetic analysis may help explain if this relates to any genetical differentiation among populations of T. khonkaenensis in Vietnam. Typhonium violifolium was first described as a new species from Thailand (under the name “ T. violaefolium ”) by Gagnepain (1942 a: 1177) but the name was validly published by his subsequent publication (Gagnepain 1942 b: 12). The species was then reported by Pham-Hoang (1970) to occur in Saigon (Ho Chi Minh City presently). This report was followed in his subsequent updates (1993 and 2000) and other later Typhonium - revising publications (e. g. Nguyen & Vu 2004, Nguyen 2017, Van 2017). All these reports did not include any vouchered specimens. Nguyen (2017) even noted that he tried but failed to find the species in Vietnam. We have recently found at the herbarium PHH a specimen named as Typhonium sp. (with code PHH 0004167) collected by Pham-Hoang from Thong Nhat Road, Saigon in September 1964. This specimen well matches his same illustration in 1970, 1993 and 2000. Our examination of the specimen indicates that it is indeed a specimen of T. khonkaenensis. According to Gagnepain (1942), Sriboonma et al. (1994) and Boyce et al. (2012), T. violifolium has a reniform to ovate leaf blade, a short petiole (ca. 6 cm long); pale green or whitish spathe that is nearly as long as spadix, short and white staminodes and a short appendix (ca. 7 cm long). On the contrary, the description by Galloway (2015) and our collections of T. khonkaenensis show that this species has highly variable leaf blades, longer petiole (6 – 12 cm long), abaxially brownish mottled, dark violet and abaxially grey to dark purple spathe that is much shorter than spadix, long and light brown staminodes and long appendix (15 – 18 cm). In fact, both Sriboonma et al. (1994) and Boyce et al. (2012) did not note any distribution of T. violifolium in Vietnam. In addition, T. violifolium grows in mixed evergreen forest on limestone while T. khonkaenensis does in open sandy soils. Therefore, it is reasonable to exclude T. violifolium from the flora of Vietnam.	en	Van, Hong Thien, Le, Van Son, Nguyen-Phi, Nga, Nguyen, Quoc Dat, Nguyen, Tran Quoc Trung, Nguyen, Hieu Cuong, Luu, Hong Truong (2021): A new species and a new record of Typhonium (Araceae) from southern Vietnam. Phytotaxa 527 (3): 201-208, DOI: 10.11646/phytotaxa.527.3.4
