[Botany • 2026] Tweeddalea capsiciformis (Araceae: Schismatoglottideae) • Unveiling the Fifteenth Species of Tweeddalea from Indonesian Borneo

 

Tweeddalea capsiciformis A.S.D.Irsyam & M.R.Hariri,

in Irsyam, Hariri et Setiawan, 2026. 

DOI: doi.org/10.1007/s12228-026-09883-0  

  linkedin.com

Abstract

A new species of the genus Tweeddalea (Araceae), Tweeddalea capsiciformis, is described and illustrated from West Kalimantan, Indonesian Borneo. This species increases the number of described species in the genus to fifteen. The discovery of T. capsiciformis not only extends the known distribution range of the genus but also highlights the rich yet still insufficiently explored diversity of Araceae in Borneo.

Keywords: Aroid, Kalimantan, Malesia, Multiflora clade, Schismatoglottideae

Tweeddalea capsiciformis.
A. Habit. B. Inflorescence position. C. Spathe. D. Spadix. E. Close-up spadix. F. Close-up staminate flowers zone. G. Close-up pistils and interstice zone.

 (A–F from the holotype.).

Tweeddalea capsiciformis A.S.D.Irsyam & M.R.Hariri., sp. nov.

  

 Etymology. The specific epithet capsiciformis refers to the chili-like shape of the spathe, which resembles the fruit of Capsicum L. (Solanaceae).

Arifin S. D. Irsyam, Muhammad R. Hariri & Ade Agus Setiawan. 2026. Unveiling the Fifteenth Species of Tweeddalea (Araceae) from Indonesian Borneo. Brittonia. DOI: doi.org/10.1007/s12228-026-09883-0 [30 April 2026] 

 linkedin.com/posts/arifin-surya-dwipa-irsyam-5b46a916a_a-new-discovery-from-the-forests-of-kalimantan-activity-7455934737178812416-w7WN

[Botany • 2026] Bau djinna (Araceae) • A New Species from the Rejang Basin, Sarawak, Malaysian Borneo [Schismatoglottideae of Borneo LXXX]

Bau djinna S.Y.Wong, P.C.Boyce & A.Hay, 

in Wong, Boyce et Hay, 2026. 

 DOI: doi.org/10.1002/fedr.70063

ABSTRACT

Bau djinna is described as a new species from Central Sarawak and compared with three species to which it is most similar. Recognition of B. djinna takes the genus to 27 species, 25 of which are endemic to Borneo. A brief note is provided on Schismatoglottis ambigua, a recently published name synonymous with Bau inculta. The paper also introduces the term ‘anthomorph’ for the flowering structure that in general is termed an inflorescence in the Araceae and explains why the term ‘bloom’ that the authors have employed previously is unsatisfactory.

Bau djinna.
 (A) Plant in habitat, the distinctive quilted leaf blades are clearly seen. (B) Stem ascending and rooting adventitiously. (C) Detail of petiole showing the longitudinal ridges and denticulate edges. All images the authors.

Bau djinna.
(A) Cluster of sequentually-maturing anthomorphs, the largest (oldest) at pistillate antheses. The cluster-preceding much-reduced foliage leaf and the prophyll associated with the second oldest anthomorphs are visible. (B) Anthomorph at end of staminate antheses with the spathe limb deliquessing. (C & D) Anthomorph at pistillate anthesis showing the full extent to which the spathe limb opens. All images the authors.

Bau djinna S.Y.Wong, P.C.Boyce & A.Hay, sp. nov  

 

  Diagnosis: Bau djinna belongs to a group of species in which during anthesis the spathe limb barely opens. Within this group B. djinna is vegetatively most similar to B. amosyui (S.Y.Wong, S.L.Low & P.C.Boyce) S.Y.Wong & P.C.Boyce (Figure 1B) and B. hendrikii (S.Y.Wong & P.C.Boyce) S.Y.Wong & P.C.Boyce (Figure 1C), differing from both by the plain deep green leaf blades and an ascending-rooting stem (vs leaf blades habitually silver variegated and stems clumping and abbreviated). Bau djinna is further distinguished from B. amosyui by lacking a partially naked interstice separating the pistillate and staminate florets, by the subcylindric (vs conical) pistillate zone long-obliquely inserted (vs barely obliquely inserted) and the blunt-tipped cream (vs pointed yellow) spadix appendix. From B. hendrikii B. djinna is distinguished by the conical stout pale green pistillate zone (vs rather slender cylindrical emerald-green), dense (vs rather lax) pistillate florets, button-like (vs broadly disk-like) stigma, and the blunt-tipped cream (vs pointed yellow) spadix appendix.

  Etymology: Djinn, in the context of ‘hidden beings’, originates from Arabic, an extension of the word meaning to hide, conceal, or cover, emphasizing the elusive and unseen nature of djinn, who are believed to inhabit a realm parallel to humans reflecting the belief that these beings are invisible to humans. Here the word is used in the feminine nominative, djinna, in the sense that the spadix is concealed by the hardly opening spathe.

Wong Sin Yeng, Peter C. Boyce and Alistair Hay. 2026. Schismatoglottideae (Araceae) of Borneo LXXX: Bau djinna, a New Species from the Rejang Basin, Sarawak. Feddes Repertorium. 137(1); e70063. DOI: doi.org/10.1002/fedr.70063 [10 March 2026]

[Botany • 2025] Sarawakia khoonmengiana (Araceae) • A New rheophytic Species from southwest Sarawak, Malaysian Borneo [Schismatoglottideae of Borneo LXXIX]

Sarawakia khoonmengiana S.Y.Wong & P.C.Boyce,
 

in Wong & Boyce, 2025. 

 Sandakania. 27;

Photos: Boyce P.C.

Sarawakia khoonmengiana is described and illustrated as a new species from Lanjak Entimau Wildlife Sanctuary, southwest Sarawak, where it is restricted to exposed shale riverbanks.

Sarawakia khoonmengiana S.Y.Wong & P.C.Boyce.
A. Plants in habitat on vertical silt-covered shales. B. Detail of leaf blade venation, abaxial surface. C. Bloom at pistillate anthesis shown in natural position. D, E. Bloom at staminate anthesis with spathe limb characteristically degrading. Note damage to the appendix in D, and the perpetrators, chrysomelid beetles. F. Bloom at late pistillate antheses with nearside spathe artificially removed, note the expanded interstice staminodes.

Photos: Boyce P.C.

Comparison of spadix morphology of five Sarawakia species.
A. Sarawakia clausula. B. Sarawakia khoonmengiana. C. Sarawakia larynx. D. Sarawakia petradoxa. E. Sarawakia rejangica. Spadix of each with spathe partially or completely removed. Photos: Boyce P.C.

Wong Sin Yeng & Peter C. Boyce. 2025. Schismatoglottideae of Borneo LXXIX: Sarawakia khoonmengiana, A New rheophytic Species from southwest Sarawak, with a conspectus of plant names dedicated to Wong Khoon Meng. Sandakania. 27; 277-284.

[Botany • 2023] Burttianthus rejangicus & B. solus (Araceae) • Two New Species from Sarawak, Malaysian Borneo [Schismatoglottideae of Borneo LXXVI]

Burttianthus rejangicus S.Y.Wong, M.Lo & P.C.Boyce, 

in Wong, Lo et Boyce, 2023. 

 oaj.fupress.net/index.php/Webbia/article/view/15209 

 Researchgate.net/publication/374585720

  facebook.com: Michael Lo

Abstract

Two new species of Burttianthus are described from Sarawak: B. rejangicus from the Rejang and Balleh rivers of the western Rejang Basin, and B. solus from the Similajau Basin, Bintulu. Both novelties are illustrated from living plants and the spadices of eight of the nine Burttianthus species are compared in accompanying figures.

Keywords: Araceae, Burttianthus, Malaysia, Kapit Division, Bintulu Division, Borneo

Burttianthus rejangicus S.Y.Wong, M.Lo & P.C.Boyce, sp. nov.

Diagnosis: Burttianthus rejangicus is unique by the fusiform pistillate floret zone narrower than the staminate floret zone, the almost inflated rims to the stamens, and by the dull pale green stigmas with a central depression.

Etymology: From Rejang, plus Greek -ikos [-icos], indicating belonging to. 

Distribution: Known only from the Rejang and Balleh rivers of the western Rejang basin where the small populations are widely scattered.

Burttianthus solus S.Y.Wong, M. Lo & P.C.Boyce.
A. Plants in habitat. B. Bloom during pistillate anthesis. C. Bloom at pistillate anthesis, nearside spathe artificially removed. D. Bloom at onset of staminate anthesis, spathe limb beginning to shed. E. Lower persistent splash-cup spathe with the fruits decomposing and seed beginning to germinate.

 Photos: P.C.Boyce.

Burttianthus solus S.Y.Wong, M.Lo & P.C.Boyce, sp. nov.

 

Diagnosis: Burttianthus solus is distinguished from all other species by the pistillate and staminate zones of florets separated by a naked interstice, and further by the lax (not congested) pistillate florets.

Etymology: Latin, sōlus (feminine sōla, neuter sōlum); alone, sole, only, by oneself with no others around – in allusion to the separation of the pistillate and staminate zones, and the laxly arranged pistillate florets.

Sin Yeng Wong, Michael Lo and Peter C. Boyce. 2023. Schismatoglottideae (Araceae) of Borneo LXXVI — Two new Burttianthus species from Sarawak. Webbia. 78(2); 123-129. DOI: 10.36253/jopt-15209  oaj.fupress.net/index.php/Webbia/article/view/15209

  Researchgate.net/publication/374585720_Two_new_Burttianthus_species_from_Sarawak

  facebook.com/junglemike/posts/10159964957773528

[Botany • 2022] Schottarum inconspicuum (Araceae) • A New Species from Sarawak, Malaysian Borneo [Schismatoglottideae of Borneo LXXII]

Schottarum inconspicuum S.Y.Wong, & P.C.Boyce, 

in Wong & Boyce, 2022. 

DOI: 10.36253/jopt-12176 

  Researchgate.net/publication/360079701

Abstract

Schottarum inconspicuum S.Y.Wong & P.C.Boyce, is described as a new species from the easten part of the Rejang Basin, taking the genus to three species. All are illustrated from living plants. A distribution map is provided.

 Keywords: Schottarum, Rejang Basin, Borneo, shales

Schottarum inconspicuum
(A) Plants in habitat. (B) Bloom at staminate anthesis. Leaf blade abaxial surface showing the fine venation. (C) Spadix at staminate anthesis, spathe artificially removed. (D) Detail of staminate zone with pollen shed in fine dense strings.

All from AR-117.

Schottarum inconspicuum S.Y.Wong, & P.C.Boyce, sp. nov.

Diagnosis: Schottarum inconspicuum differs from both S. josefii and S. sarikeense by the fusiform (vs bluntly conic)spadix appendix equalling (vs about half as long as) the staminate floret zone, by the pistillate floret zone being about one third free (vs fully adnate or at most only slightly free from the spathe), and the much smaller and more densely congested pale green pistillate florets.

Etymology: From Latin, inconspicuus (neuter inconspicuum), unremarkable – in allusion to the small and easily over-looked plants.

Wong Sin Yeng and Peter C. Boyce. 2022. Schismatoglottideae of Borneo LXXII – A New Species of Schottarum (Araceae) from Sarawak, Malaysian Borneo.  Webbia. Journal of Plant Taxonomy and Geography. 77(1); 145-152. DOI: 10.36253/jopt-12176   Researchgate.net/publication/360079701_Schismatoglottideae_of_Borneo_LXXII_-_A_new_species_of_Schottarum_from_Sarawak

[Botany • 2022] Schismatoglottis mons (Araceae: Schismatoglottideae) • A New Species from Sabah, Malaysian Borneo

Schismatoglottis mons Kartini, 

in Kartini, 2022. 

DOI: 10.36253/jopt-13274

Abstract

Schismatoglottis mons Kartini is described as taxonomically novel species assigned to the Asperata Complex. Schismatoglottis mons is a highland mesophytic species found at c. 718 m a.s.l. most like lowland Schismatoglottis gillianiae P.C. Boyce and Schismatoglottis shaleicola P.C.Boyce & S.Y.Wong.

Keywords: Araceae, Malaysian Borneo, Schismatoglottideae, Schismatoglottis

Schismatoglottis mons
 A: flowering plant in habitat; B: inflorescence at onset of pistillate anthesis (spathe artificially removed);
C: pistillate zone (spathe artificially removed); D: inflorescence at late of pistillate anthesis (spathe artificially removed); E: spathe limb irregu-larly crumbling and breaking away after staminate anthesis; F: marcescent ligular petiolar leaf sheath

– All from Kartini BORH 2708. 

– All photographs by Kartini Saibeh.

Schismatoglottis mons Kartini, sp.  nov.

Diagnosis: The inflorescence of Schismatoglottis mons is most similar to that of rheophytic S. gillianiae. However, S. gillianiae has a very short peduncle (c. 2-3.5 cm long-, fleshy persistent ligular petiolar sheaths and narrowly oblanceolate leaves whereas S. mons have long peduncle c.10 cm, a marcescent free ligular petiolar sheath and ovate to oblong-ovate leaves. Schismatoglottis mons differs from mesophytic S. shaleicola by the inflorescence peduncle up to 10 cm long, the yellow spadix, a slender cylindrical appendix about twice as long as remainder of spadix, pink sterile interstice

Etymology: Mons, Latin meaning mountain, and referring to the occurrence of the species at altitude.

 

Kartini Saibeh. 2022. A New Species of Schismatoglottis (Araceae) from Sabah, Malaysian Borneo. Webbia. Journal of Plant Taxonomy and Geography.  77(2); 267-270. DOI: 10.36253/jopt-13274