Thursday, November 14, 2024

[Botany • 2024] Typhonium karsticola & T. pallescens • Two New Species and Three New Records for the Genus Typhonium [Taxonomic Studies of Araceae in Myanmar VIII]


Typhonium karsticola
T. pallescens  
K.Z.Hein, Saensouk & Naive,  

 in Hein, Saensouk et Naive, 2024. 

Abstract
As part of our ongoing research to revise and reveal the true diversity of the family Araceae in Myanmar, we describe two new Typhonium species, T. karsticola and T. pallescens, from Mon State and the Sagaing Region. Additionally, we report for the first time the occurrence of T. albidinervium, T. laoticum, and T. roxburghii in Myanmar. A detailed taxonomic account of the two new species including morphological comparison with closely similar species and relevant information on the newly recorded species are provided below. With the addition of these two new species and three newly recorded species, Myanmar now has a total of 17 Typhonium with 47% endemicity.

Keyword: Aroideae, Areae, Indochina, Karst limestone, paddy fields, Typhonium karsticola, Typhonium pallescens

Detail of spadices of Burmese Typhonium species (nearside spathe artificially removed).
A. Typhonium flagelliforme, B. T. trilobatum, C. T. neogracile, D. T. roxburghii, E. T. praecox, F. T. inopinatum,
G. T. edule, H. T. albidinervium, I. T. aungmyintwinii, J. T. sagaingense, K. T. laoticum. L. T. cordifolium.
 Photos by: K. Z. Hein.

Typhonium karsticola sp. nov.
A. Excavated plant, B. Leaf, C. Excavated flowering plants (nearside spathe artificially removed in the right photo), D. Front and side views of side views of inflorescence, E. Detail of spadix showing pistillate zone, sterile interstice, staminate zone and basal part of appendix (nearside spathe artificially removed). F. Cataphyll.
Scale bars: A.=5 cm, B.=2 cm, C.=1 cm, D. & E.=5 mm, F.=2 mm. 
Photos by: S. C. S. Paing.

Typhonium karsticola K.Z.Hein, Saensouk & Naive, sp. nov. 

Diagnosis: Typhonium karsticola is most similar to Typhonium orbifolium Hett. & Sookch. from Thailand (Hetterscheid et al., 2001), but it differs in having a hysteranthous habit (vs. synanthous in T. orbifolium), clavate staminodes with a red or reddish-white slender base and a white globose head (vs. white clavate staminodes in T. orbifolium), a shorter staminate zone (ca. 4 mm vs. 9–10 mm in T. orbifolium), yellow stamens (vs. white stamens in T. orbifolium), and a spreading declinate appendix (vs. erect in T. orbifolium). The shape of the staminodes in Typhonium karsticola resembles those of Typhonium praelongum Serebryanyi & Hett. from Vietnam (Serebryanyi et al., 2023), but it differs significantly by having a depressed-globose tuber (vs. conic tuber in T. praelongum), a much shorter peduncle (0.3–0.4 cm vs. 6–7 cm in T. praelongum), a spathe limb 3–4 times longer than the spathe tube (vs. spathe limb 7– 9 times longer than the spathe tube in T. praelongum), and a shorter spadix (ca. 7 cm vs. ca. 35 cm in T. praelongum).

Etymology: The specific epithet ‘karsticola’ is derived from the German noun ‘karst’ (referring to a limestone landscape), and the Latin suffix ‘-cola’, (meaning inhabitant of or dwelling in), with reference to the species’ habitat preference being crevices of limestone within karst landscapes.


Typhonium pallescens sp. nov. 
A. Cultivated flowering plant, B. Leaf, C. Front and side views of inflorescence at early pistillate anthesis with emerging young inflorescence, D. Side view of inflorescence at late pistillate anthesis E. Detail of spadix showing pistillate zone, sterile interstice, staminate zone and basal part of appendix (nearside spathe artificially removed).
Scale bars: A.=5 cm, B.=3 cm, C. & D.=2 cm, E.=1 cm. 
Photos by: K. Z. Hein. 

Typhonium pallescens K.Z.Hein, Saensouk & Naive, sp. nov.

Diagnosis: Typhonium pallescens is unique within the genus by the pedatisect leaf blade with up to 11 linear lobes, the simultaneous development of 2 or 3 inflorescences, and the adaxial surface of the spathe limb which is dark purple during early pistillate anthesis and gradually becomes pale purplish-brown at late pistillate anthesis. The pedatisect leaf blade of T. pallescens closely resembles that of T. pedatisectum Gage from Magway Region, Myanmar (Gage, 1903) with up to 11 linear lobes, but it differs by having a lanceolate spathe limb (vs. ovate spathe limb in T. pedatisectum), a white sterile interstice (vs. pink or red in T. pedatisectum), and an ivory or pale orange appendix (vs. purplish-black in T. pedatisectum).

Etymology: The specific epithet is derived from the Latin ‘pallescens’ (becoming pale), referring to the adaxial surface of the spathe limb, which is dark purple during early pistillate anthesis and gradually becomes pale purplish brown at late pistillate anthesis.  

   

Khant Zaw Hein, Surapon Saensouk and Mark Arcebal K. Naive. 2024. Taxonomic Studies of Araceae in Myanmar VIII: Two New Species and Three New Records for the Genus Typhonium. Taiwania. 69(4); 537-544. DOI: 10.6165/tai.2024.69.537  taiwania.ntu.edu.tw/abstract/2033