Monday, October 24, 2022

[Botany • 2022] Impatiens hambaeksanensis (Balsaminaceae) • A New Species from South Korea


Impatiens hambaeksanensis   B.U.Oh, 

in Oh, Jang, Lee et  Oh, 2022. 
 All photos by Byoung-Un Oh.

Abstract
A new species Impatiens hambaeksanensis from Gangwon-do, South Korea, is described and illustrated, based on its morphology and distribution. I. hambaeksanensis is different from I. furcillata, another similar Impatiens species in South Korea, in some ways: I. hambaeksanensis possesses a serrate leaf margin with flat tooth tip, while I. furcillata possesses a crenate leaf margin with erect tooth tip; it has an erect inflorescence, while I. furcillata has a pendulous inflorescence; it has a smaller flower which is 2–2.6 cm long, while I. furcillata has a flower of 2.3–3.2 cm; the flower is white or pinkish-white with yellowish and purplish spots, while I. furcillata has a white lower sepal and pinkish-white lateral united petals with yellowish spots; the distal part of the lower sepal is mostly not coiled or rarely 1-coiled, while that of I. furcillata is never coiled; the spur tip is expanded, round and slightly biparted, while that of I. furcillata is expanded, ellipsoidal and clearly biparted. A taxonomic description, a holotype and photos of morphological characteristics of the new species are provided. A table which includes the morphological comparison and a geographical distribution map are presented as well.

Keywords: Gangwon-do, Korean endemic, morphology, new species, taxonomy

Reproductive organs and their vasculatures of Impatiens hambaeksanensis (White spots between veins are raphides) A frontal view of flower B lateral view of flower C lateral sepals D lower sepal E dorsal petal F lateral united petals G stamen H pistil.
Scale bars: 5 mm (D); 2 mm (C, E, F, G, H).

Morphological characteristics of Impatiens hambaeksanensis
A habit B stem C leaf D inflorescence E frontal view of flower F lateral view of flower G fruit H seed.
All photos by Byoung-Un Oh.

 Impatiens hambaeksanensis B.U.Oh, sp. nov.
 
Diagnosis: I. hambaeksanensis is similar to I. furcillata in its overall characteristics, including taproot, alternate phyllotaxis and racemose inflorescence, but different from it in some ways: I. hambaeksanensis has serrate leaf margin with flat tooth tip; inflorescence is erect; flower is smaller and mostly white or rarely pinkish-white; the distal part of the lower sepal is mostly non-coiled or rarely 1-coiled; the spur tip is expanded, round and slightly biparted.

Major morphological differences between Impatiens hambaeksanensis (A–D) and I. furcillata (E–H)
 A, E inflorescences B, F lateral view of flowers and spur tip directions C, G leaves (C1, G1 bird’s-eye view C2, G2 lateral view) D, H shape of spur tips.
Scale bar: 0.3 mm (D, H). All photos by Byoung-Un Oh.


Ami Oh, Hyun-Do Jang, Jung Sim Lee and Byoung-Un Oh. 2022. Impatiens hambaeksanensis (Balsaminaceae), A New Species from South Korea. PhytoKeys 211: 139-150. DOI: 10.3897/phytokeys.211.90236