Diversity, Utilization, and Conservation Status of Araceae in Kalasin Province, Northeastern Thailand

Abstract

The Araceae family exhibits remarkable morphological and ecological diversity, playing a significant role in horticulture, agriculture, and traditional practices. Despite Thailand’s rich aroid diversity, Kalasin Province remains underexplored in terms of species distribution, ecology, and local utilization. This research aimed to document the diversity, habitat preferences, and local uses of Araceae in Kalasin Province. Field surveys, herbarium studies, and interviews with local communities were conducted to record species occurrences and assess their applications. A total of 51 species, representing 24 genera and 5 subfamilies, were identified, with 13 species found in the wild and 43 in cultivation. Wild species demonstrated pronounced ecological specialization, thriving in natural habitats, while cultivated species dominated across all districts, reflecting socio-economic and cultural influences. All recorded species were utilized in at least one category, including food, medicine, ornamental purposes, and cultural practices. Notably, Alocasia macrorrhizos and Colocasia esculenta were the most extensively used, contributing to multiple utilization categories. This study also proposed preliminary conservation status of wild species, with several species proposed as Vulnerable due to habitat degradation and limited distribution. These findings contribute to a better understanding of Kalasin’s aroid flora and emphasize the importance of conservation efforts in the face of agricultural expansion and habitat alteration. This study provides a foundation for the sustainable management and preservation of Araceae biodiversity in northeastern Thailand.

1. Introduction

Araceae Juss. is a well-defined monophyletic family, currently comprising approximately 150 recognized genera and about 4600 species [1,2,3]. These herbaceous monocotyledons represent one of the earliest-diverging lineages within the order Alismatales [4,5,6]. Recent phylogenetic analyses classify the family into seven subfamilies: Gymnostachydoideae, Orontioideae, Lemnoideae, Lasioideae, Pothoideae, Monsteroideae, and Aroideae [7]. Many species of Araceae are globally significant in horticulture and agriculture, being cultivated widely as ornamentals, food sources, or medicinal plants [7,8,9,10]. The family exhibits remarkable ecological diversity, encompassing floating or submerged aquatics, helophytes, rheophytes, geophytes, large arborescent herbs, nomadic vines, and epiphytes [11,12,13,14,15,16]. In addition to their diverse life forms, Araceae species inhabit a wide range of natural habitats, including freshwater aquatic and wetland habitats, marshy and tidal swamps, moist to wet tropical evergreen forests, seasonally wet lowland and highland forests, deciduous or monsoon forests with distinct dry periods, dry or semi-dry forests such as savannas and open bushland, and rocky or humus-rich substrates in seasonally moist forests [11,12,16]. They also span extremes in size, from Wolffia globosa (Roxb.) Hartog & Plas, the smallest known species, to Amorphophallus titanum (Becc.) Becc., which bears the largest unbranched inflorescence [7,17]. While Araceae has a global distribution, its diversity peaks in equatorial and humid tropical climates, particularly in South and Central America and Southeast Asia [9,12,16]. In contrast, species richness and the variety of life forms decrease in subtropical and temperate climates [9].

The aroid flora of Thailand includes 30 genera, incorporating the 4 former Lemnaceae genera, with approximately 210 recorded species, 78 of which (over 36%) are endemic [18,19]. Although the country’s aroid diversity is lower than that of Malaysia and Indonesia, it remains one of the richest in Mainland Southeast Asia, particularly in terms of species adapted to diverse climatic conditions [13,18]. In comparison with the aroid flora of neighboring countries, Thailand has a relatively high number of aroid species, with Cambodia recording 52 species, Laos 85 species, Myanmar 120 species, Peninsular Malaysia 138 species, and Vietnam 140 species [19,20]. A key feature of Thailand’s aroid flora is the dominance of geophytic species, which account for a significant proportion of the taxa [18]. These geophytes possess hypogeal storage structures, such as tubers or rhizomes, an adaptation likely shaped by the country’s strong monsoonal climate [18,21].

Kalasin Province is one of the 20 provinces in northeastern Thailand, collectively known as the Isan region, which is the largest and most populous in Thailand [22,23,24,25]. Kalasin, as part of this region, has a landscape dominated by agricultural activities, with a large portion of its population engaged in farming, which plays a significant role in the province’s economy [22,23]. Although Thailand is known for its rich diversity of aroids, reports on aroid species in Kalasin Province are limited. In the Flora of Thailand, Amorphophallus krausei Engl. is the only aroid species recorded from the province [18]. Additionally, Amorphophallus brevispathus Gagnep. is recognized for its use by local communities as an edible plant in Kalasin Province [23,24]. Despite these reports, the overall diversity of Araceae in Kalasin remains poorly documented and understood. There have been no comprehensive studies on the utilization of aroids, nor has their conservation status been evaluated. Given the province’s extensive agricultural activities and habitat changes, a comprehensive study is essential to understand the diversity, ecological roles, traditional uses, and conservation concerns of Araceae in Kalasin Province.

This article aims to enhance the understanding of Araceae diversity in Kalasin Province through the following specific objectives: (a) documenting species diversity, distribution, and ecological and habitat preferences; (b) investigating the utilization of Araceae species by local communities; and (c) assessing the conservation status and threats to the survival of wild Araceae species. The research will provide insights into the conservation needs of Araceae in the context of agricultural changes. Additionally, it will contribute to the sustainable management of aroid resources, promoting biodiversity preservation and supporting future conservation and agricultural practices in Kalasin Province.

2. Materials and Methods

2.1. Study Area

This study was conducted in Kalasin Province (Figure 1), located in the northeastern region of Thailand, within coordinates ranging from 16°10′54.3″ N to 17°6′4.0″ N and 103°5′48.5″ E to 104°14′45.9″ E [26]. Covering an area of approximately 6946.746 km², Kalasin borders Udon Thani and Sakon Nakhon to the north, Mukdahan to the east, Roi Et and Maha Sarakham to the south, and Maha Sarakham and Khon Kaen to the west [27]. The province is divided into 18 districts, with about 27% of its area forested [27]. The landscape is predominantly hilly, interspersed with lowlands along the Chi, Pao, and Phan Rivers [26,27]. Elevation ranges from 128 m to 648 m at the highest peak, Phu Mak Yo, with an average elevation of 200 m [26]. Kalasin includes parts of Phu Phan National Park and Phu Pha Lek National Park, falling within the northeastern floristic region as defined by the Flora of Thailand [18,27,28]. The vegetation of Kalasin Province is typical of the northeastern floristic region, including deciduous to mixed deciduous forests, with some tracts of evergreen or dry evergreen forests, where species of Dipterocarpaceae Blume are common [28]. Kalasin experiences a monsoon climate with distinct wet and dry seasons [29]. The monsoon season typically runs from May to October, bringing the majority of the region’s annual precipitation of 1387 mm, with the heaviest rains occurring in August and September [29,30]. April is the hottest month, while December and January are the coldest [30]. The geological substrates of Kalasin Province are primarily associated with the Early Cretaceous Khok Kruat Formation, which is part of the Khorat Group [31]. This formation consists of reddish-brown, fine- to medium-grained sandstones, limestones, siltstones, mudstones, and conglomerates [31].

2.2. Plant Material Collection

Surveys and specimen collections of the Araceae family in Kalasin Province were conducted monthly from January to December 2024. Fieldwork was conducted 2 to 4 times per month across 62 designated sites distributed throughout all 18 districts of Kalasin Province. To ensure comprehensive coverage of the ecological diversity of the Araceae family within the province, 3 to 4 sites were selected per district, representing all habitat types, including forests, wetlands, urban areas, and other accessible locations. The collections included dry specimens, spirit specimens, and living specimens. Dry specimens were processed using a heater, spirit specimens were preserved in 70% ethyl alcohol, and living specimens were cultivated in the greenhouse at Mahasarakham University. Dry and spirit specimens were deposited at the Vascular Plant Herbarium, Mahasarakham University (VMSU). In national park areas, no specimens were collected; only photographic records and field notes were documented.

2.3. Species Identification

The morphological characteristics of the collected Araceae specimens were examined using precise measurements with rulers and vernier calipers (Mitutoyo Vernier Caliper (Mitutoyo Corporation, Kawasaki, Japan), and detailed observations were made under a stereoscopic microscope (Stemi 2000-C, Zeiss, Oberkochen, Germany). Species identification was carried out using identification keys and by comparing the descriptions in the Flora of Thailand and The Genera of Araceae [12,18]. For further accuracy, the specimens were compared with protologues and Araceae type specimens from Thailand and neighboring countries. High-resolution images of these specimens were examined from various herbaria, including A, AAU, B, BK, BKF, C, CAL, CMU, E, HITBC, K, KKU, KUN, L, M, MO, P, PE, QBG, and SING, accessed via JSTOR Global Plants at https://plants.jstor.org/ (accessed on 3 January 2025) [32] and the Global Biodiversity Information Facility (GBIF) at https://www.gbif.org (accessed on 3 January 2025) [33]. The nomenclature of accepted names of Araceae species in Kalasin Province was verified and adopted from Plants of the World Online (POWO) at https://powo.science.kew.org (accessed on 3 January 2025) [19].

2.4. Distribution and Ecological Study

Species data were collected and organized by district, distinguishing between wild plants, cultivated plants, and those found in both wild and cultivated settings. To verify distribution status, species were classified as native or introduced based on information from the Plants of the World Online (POWO) database (https://powo.science.kew.org/) [19] and distribution records from Flora of Thailand Araceae, along with other relevant research publications [12,18]. For wild species, the number of recorded occurrences was documented whenever possible to support the assessment of their conservation status. These records were derived from field surveys and herbarium collections. Wild species found in natural forests were recorded along with their respective forest types. Species cultivated for ornamental or practical purposes in homes or gardens were categorized as cultivated (CT).

2.5. Phenological Observations

This study examines the phenological patterns of Araceae species in Kalasin Province, focusing on the timing and duration of flowering and fruiting cycles. Regular field observations were conducted throughout the year to monitor the developmental stages of each species. Data were systematically recorded, with each month represented numerically from 1 (January) to 12 (December) to facilitate the analysis of seasonal variations. These observations aim to provide insights into the reproductive behavior of Araceae in relation to the region’s climatic conditions.

2.6. Study on Utilization

Data on the use of Araceae species in Kalasin Province were collected through structured interviews with 360 local residents, equally distributed by gender (10 males and 10 females) from each of the 18 districts. The total number of participants consisted of 180 males and 180 females, all of whom were permanent residents of their own homes within the province, excluding those living in rental accommodations. Informed consent was obtained from all participants prior to the interviews, ensuring they were fully aware of the study’s purpose and participated voluntarily. The interviews focused exclusively on identifying plant species, the specific parts used, and their various applications. Personal information was not requested or recorded, and, due to the nature of the survey, formal ethics approval was not required.

2.7. Conservation Status and Threats

This study assessed the conservation status and threats to wild Araceae species in Kalasin Province using a two-fold approach. First, the existing conservation statuses of species were compiled from the IUCN Red List Website [34] and accessed by other researchers. In addition, a localized conservation assessment of wild Araceae species in Kalasin Province was conducted, following the IUCN Red List Categories and Criteria, Version 16 (March 2024) [35]. To apply Criterion B of the IUCN Red List, the extent of occurrence (EOO) and area of occupancy (AOO) were estimated using GeoCAT (Geospatial Conservation Assessment Tool) (Version [Latest Version], 2025, Royal Botanic Gardens, Kew, Richmond, United Kingdom) [36]. EOO was calculated as the minimum convex polygon encompassing all known occurrence points, while AOO was determined using a 2 × 2 km grid cell method, representing the area essential for the species’ survival [36]. The assessment also evaluated whether the species met at least two of the three subcriteria under Criterion B: (a) severe fragmentation or a limited number of locations; (b) a continuing decline in any of the following: extent of occurrence, area of occupancy, area, extent and/or quality of habitat, number of locations or subpopulations, or number of mature individuals; and (c) extreme fluctuations in any of the following: extent of occurrence, area of occupancy, number of locations or subpopulations, or number of mature individuals [35].

2.8. Statistical Analysis

Jaccard’s Similarity Index

Species diversity across the eighteen districts of Kalasin and the distribution of species across various habitat types were assessed using Jaccard’s similarity index (JI), which measures the similarity between two sets. The formula for calculation is

$$\mathrm{JI}={\displaystyle \frac{\mathrm{a}}{\mathrm{a}+\mathrm{b}+\mathrm{c}}}$$

where “a” represents the species found in both districts or habitat types, “b” refers to species unique to the first district or habitat type, and “c” represents species unique to the second district or habitat type. This index provided a quantitative comparison of species diversity across the districts and a measure of species distribution across different environmental conditions. Two-way hierarchical clustering analysis was conducted using the similarity matrix derived from the Jaccard index (JI). The matrix was processed through the unweighted pair group method with arithmetic mean (UPGMA) to determine the relationships between the districts and habitat types. Clustering and dendrogram construction were performed using the Past4 program (version 4.15) [37]. The resulting dendrograms provided visual representations of the hierarchical clustering of districts and habitat types based on their species composition, revealing ecological relationships and biodiversity patterns across the region.

3. Results

3.1. Diversity of Araceae in Kalasin Province

The diversity of Araceae in Kalasin Province comprises 51 species across 24 genera, classified into 5 subfamilies (

Table 1. Diversity of Araceae species found in Kalasin Province, along with their vernacular names, distribution, conservation status, ecology, phenology, utilization, and specimen vouchers.

No.	Scientific Name	Vernacular Name	Native Status in Thailand	Distribution Of Species Across the Districts of Kalasin Province																		Conservation Status	Proposed by Authors	Ecology of Wild Species	Phenology		Utilization		Voucher
				Don Chan	Huai Mek	Huai Phueng	Kamalasai	Kham Muang	Khao Wong	Khong Chai	Kuchinarai	Mueang Kalasin	Na Khu	Na Mon	Nong Kung Si	Rong Kham	Sahatsakhan	Sam Chai	Somdet	Tha Khantho	Yang Talat				Flowering	Fruiting	Purposes	Used Parts
1	Aglaonema commutatum Schott	Kaew Kanjana	ITD	CT	-	-	-	CT	-	CT	CT	-	-	-	CT	-	-	-	-	CT	-				6–9	10–12	Or, Ri, Co	P	KLS001
2	Aglaonema costatum N.E.Br.	Po Num Ngern	NTV	-	CT	-	-	CT	CT	-	-	-	-	CT	-	-	-	CT	-	-	CT				3–6	8–10	Or, Ri, Co	P	KLS002
3	Aglaonema modestum Schott ex Engl.	Keaw Muen Pee	NTV	CT	CT	CT	CT	CT	-	CT	-	CT	CT	CT	CT	CT	-	CT	CT	CT	CT				3–5	7–9	Or, Ri, Co	P	KLS003
4	Aglaonema nitidum (Jack) Kunth	Rio Ngern	NTV	CT	-	CT	CT	CT	CT	-	-	CT	-	CT	CT	-	CT	CT	CT	CT	CT				1–12	1–12	Or, Ri, Co	P	KLS004
5	Alocasia cucullata (Lour.) G.Don	Nangkwak	NTV	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				5	Not seen	Or, Ri, Co	P	KLS005
6	Alocasia fornicata (Kunth) Schott	Kradat Dong	NTV	-	-	-	-	CT	CT	-	-	-	-	-	-	-	-	-	WD	-	-	LC	VU	DEF, EF	6–8	10–12	Or, Co	P	KLS006
7	Alocasia longiloba Miq.	Wan Phaya Chong Ang	NTV	-	CT	-	-	CT	CT	-	-	CT	-	-	-	-	-	CT	-	CT	CT				8–10	Not seen	Or, Co	P	KLS007
8	Alocasia macrorrhizos (L.) G.Don	Kra Dat Dam	NTV	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				6–8	10–12	Fo, Me, Or, An, Co	S, P	KLS008
9	Alocasia sanderiana W.Bull	Kaew Sarapat Nuek	ITD	CT	CT	-	CT	-	-	CT	-	CT	-	-	-	-	CT	-	-	-	-				6–8	Not seen	Or, Ri, Co	P	KLS009
10	Amorphophallus brevispathus Gagnep.	Buk	NTV	-	-	-	-	-	-	-	-	WD	-	-	-	-	-	-	-	-	-	NE	EN	DF	5–6	8–10	Fo	L, Fl	KLS010
11	Amorphophallus harmandii Engl. & Gehrm.	Buk	NTV	-	-	-	-	-	-	-	WD	-	-	-	-	-	-	-	-	-	-	NE	VU	DF, MDF	5–7	8–10	Fo	L, Fl	KLS011
12	Amorphophallus krausei Engl.	Buk	NTV	-	-	-	-	WD	-	-	-	-	-	-	-	-	-	-	-	-	-	NE	DD	DF, MDF	5–6	8–10	Fo	L, Fl	KLS012
13	Amorphophallus lacourii Linden & André	Buk	NTV	-	-	-	-	-	-	-	WD	-	-	-	-	-	-	-	WD	-	-	NE	VU	DF, MDF	5–8	8–10	Fo	L, Fl	KLS013
14	Amorphophallus paeoniifolius (Dennst.) Nicolson	Buk Khangkhok	NTV	-	-	-	-	BT	-	-	-	-	-	BT	-	-	-	-	-	-	-	LC	LC	DF, MDF	5–6	8–10	Fo, Me, Co	S, L, Fl, P	KLS014
15	Anthurium hookeri Kunth	Anthurium Rang Nok	ITD	-	CT	CT	CT	-	CT	-	-	CT	CT	-	-	-	-	CT	-	-	CT				5–6	7–9	Or, Ri, Co	P	KLS015
16	Caladium bicolor (Aiton) Vent.	Bon Si	ITD	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				8–9	10–11	Or, Ri, Co	P	KLS016
17	Colocasia esculenta (L.) Schott	Phueak	NTV	BT	BT	BT	BT	BT	BT	BT	BT	BT	BT	BT	BT	BT	BT	BT	BT	BT	BT	LC	LC	WAH	8–9	10–11	Fo, Me, Or, An, Co	S, L, Fl, P	KLS017
18	Dieffenbachia longispatha Engl. & K.Krause	Sait Tee Wilson	ITD	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				6–8	Not seen	Or, Ri, Co	P	KLS018
19	Dieffenbachia seguine (Jacq.) Schott	Saow Noi Pra Paeng	ITD	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				3–9	Not seen	Or, Ri, Co	P	KLS019
20	Epipremnum aureum (Linden & André) G.S.Bunting	Phlu Daang	ITD	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				Not seen	Not seen	Or, Ri, Co	P	KLS020
21	Epipremnum pinnatum (L.) Engl.	Phlu Chang	NTV	CT	CT	CT	CT	-	-	-	-	CT	-	-	-	CT	-	-	CT	CT	CT				4–7	9–11	Or, Co	P	KLS021
22	Hapaline benthamiana Schott	Bon Tao	NTV	-	-	-	-	-	-	-	WD	-	-	-	-	-	-	-	WD	-	-	NE	VU	EF, DF, MDF	5–8	9–10	Fo	L, Fl	KLS022
23	Homalomena aromatica (Spreng.) Schott	Tao Kiat	NTV	-	-	-	-	-	-	CT	-	-	-	CT	-	-	-	-	-	-	-				6–9	Not seen	Or, Ri, Co	P	KLS023
24	Homalomena expedita A.Hay & Hersc.	Phat Bok Riow	ITD	-	-	-	-	-	-	CT	-	-	-	-	-	-	-	-	-	-	-				5–7	Not seen	Or, Co	P	KLS024
25	Homalomena pendula (Blume) Bakh.f.	Sa Neh Jan Daeng	ITD	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				6–9	Not seen	Or, Ri, Co	P	KLS025
26	Lasia spinosa (L.) Thwaites	Phak Naam	NTV	-	-	CT	-	CT	CT	-	-	-	-	CT	CT	-	CT	CT	CT	CT	-				7–9	10–12	Fo, Me, Or, An, Co	L, Fl, P	KLS026
27	Lemna aequinoctialis Welw.	Nhae	NTV	-	-	CT	-	-	CT	-	-	CT	-	CT	CT	-	-	-	-	CT	BT	LC	LC	WAH	1–12	1–12	Or, An, Co	P	KLS027
28	Leucocasia gigantea (Blume) Schott	Bon Yaak	NTV	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				4–6	8–10	Fo, Me, An, Co	S, L, P	KLS028
29	Monstera deliciosa Liebm.	Phlu Cheek, Phlu Chaek, Monstera	ITD	-	CT	CT	CT	-	-	-	-	CT	-	CT	CT	-	-	CT	CT	-	CT				3–6	8–10	Fo, Or, Ri, Co	Fr, P	KLS029
30	Philodendron billietiae Croat	Philo Gaan Som	ITD	-	-	-	-	-	-	-	-	CT	-	-	-	-	CT	-	-	-	-				7–10	Not seen	Or, Co	P	KLS030
31	Philodendron bipinnatifidum Schott ex Endl.	Philo See Lorm	ITD	-	-	-	-	-	CT	-	-	-	-	-	-	-	-	-	-	-	-				6–8	Not seen	Or, Co	P	KLS031
32	Philodendron erubescens K.Koch & Augustin	Morrakot Daeng	ITD	-	-	-	-	CT	CT	CT	-	-	-	-	CT	CT	-	-	-	-	-				3–6	Not seen	Or, Co	P	KLS032
33	Philodendron hederaceum (Jacq.) Schott	Philo Bai Hua Jai	ITD	-	-	-	-	-	-	-	-	-	-	CT	-	-	-	-	-	-	-				3–8	Not seen	Or, Co	P	KLS033
34	Philodendron lacerum (Jacq.) Schott	Philo Bai A-ngoon	ITD	-	-	-	-	-	-	-	-	CT	-	-	-	-	-	-	-	-	-				5–6	Not seen	Or, Co	P	KLS034
35	Philodendron longilobatum Sakur.	Philo Longi Lelano	ITD	-	CT	-	-	-	-	CT	-	-	-	-	CT	-	CT	-	-	-	-				Not seen	Not seen	Or, Co	P	KLS035
36	Philodendron melinonii Brongn. ex Regel	Philo Sait Tee Ruay Sap, Sait Tee Mee Sap	ITD	CT	CT	CT	CT	CT	CT	CT	-	CT	-	CT	CT	CT	CT	CT	CT	CT	CT				3–8	Not seen	Or, Co	P	KLS036
37	Philodendron sp. ‘Burle Marx’	Philo Morrakot Yok	ITD	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				Not seen	Not seen	Or, Ri, Co	P	KLS037
38	Philodendron sp. ‘Lemon Lime’	Philo Si Thong	ITD	CT	-	-	CT	-	CT	-	-	CT	-	-	CT	-	-	CT	-	-	-				Not seen	Not seen	Or, Ri, Co	P	KLS038
39	Philodendron spruceanum G.S.Bunting	Philo Nuat Plaa Muek	ITD	-	-	-	-	-	-	-	-	CT	-	-	-	-	-	-	-	-	-				Not seen	Not seen	Or, Co	P	KLS039
40	Philodendron undulatum Engl.	Philo Bai Kluen	ITD	-	-	-	-	-	-	-	-	CT	-	-	-	-	-	-	-	-	-				Not seen	Not seen	Or, Co	P	KLS040
41	Philodendron xanadu Croat, Mayo & J.Boos	Xanadu	ITD	CT	-	-	-	-	-	-	-	-	-	-	-	-	-	CT	-	-	-				5–6	Not seen	Or, Co	P	KLS041
42	Phyllotaenium lindenii André	Xanthosoma	ITD	-	-	-	-	-	-	-	-	-	-	CT	-	-	-	-	-	-	-				6–11	Not seen	Or, Co	P	KLS042
43	Pistia stratiotes L.	Jork	NTV	-	CT	-	CT	CT	CT	CT	-	-	-	CT	-	-	-	-	-	-	CT				5–11	6–12	Or, An, Co	P	KLS043
44	Scindapsus officinalis (Roxb.) Schott	Phlu Chaang	NTV	-	-	-	-	-	-	-	WD	-	-	-	-	-	-	-	-	-	-	NE	VU	DEF, EF, DF, MDF	6–8	9–10	Me	Fr	KLS044
45	Spathiphyllum wallisii Regel	Nah Wua Thai, Dehlee	ITD	-	-	-	-	-	-	-	-	-	CT	-	-	-	-	CT	-	-	-				3–8	Not seen	Or, Ri, Co	P	KLS045
46	Syngonium podophyllum Schott	Ngern Lai Ma	ITD	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				6–8	Not seen	Or, Ri, Co	P	KLS046
47	Typhonium flagelliforme (G.Lodd.) Blume	Wan Phraya Hok Hak	NTV	-	-	-	-	-	-	-	WD	-	-	-	-	-	-	-	-	-	-	LC	LC	WAH	4–5	6–8	Me	S, L	KLS047
48	Typhonium trilobatum (L.) Schott	Utta Phit	NTV	WD	WD	WD	-	WD	WD	WD	-	WD	-	WD	WD	-	WD	WD	WD	WD	WD	NE	LC	MDF, WAH	5–7	8–9	Me, Ri	S, P	KLS048
49	Wolffia globosa (Roxb.) Hartog & Plas	Phaam	NTV	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	BT	LC	LC	WAH	Not seen	Not seen	Fo, Me, An, Co	P	KLS049
50	Xanthosoma sagittifolium (L.) Schott	Bon Kradat Dam	ITD	-	CT	CT	CT	CT	-	CT	CT	CT	-	CT	CT	-	CT	CT	CT	CT	CT				7–8	Not seen	Fo, Me, Or, An, Co	S, L, P	KLS050
51	Zamioculcas zamiifolia (G.Lodd.) Engl.	Kwak Morrakot	ITD	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT	CT				7–9	Not seen	Or, Ri, Co	P	KLS051

Abbreviations: Distribution—native species (NTV), introduced species (ITD), both cultivated and wild (BT), cultivated (CT), wild (WD); conservation status—data deficient (DD), endangered (EN), least concern (LC), not evaluated (NE), vulnerable (VU); ecology—deciduous forests (DF), dry evergreen forests (DEF), evergreen forests (EF), mixed deciduous forests (MDF), wetland-associated habitats (WAH); months—January (1), February (2), March (3), April (4), May (5), June (6), July (7), August (8), September (9), October (10), November (11), December (12); utilization—animal fodder (An), commercial cultivation (Co), food (Fo), medicine (Me), ornamental (Or), rituals (Ri); part used—inflorescences (Fl), infructescences (Fr), leaves (L), stems (S), whole plant (P). Note: the gray background color of the cell indicates that the species is not found in the wild in Kalasin Province.

and Figure 2). The most diverse subfamily, Aroideae, includes 16 genera and 42 species: Aglaonema Schott (4 spp.), Alocasia (Schott) G.Don (5 spp.), Amorphophallus Blume ex Decne. (5 spp.), Caladium Vent. (1 sp.), Colocasia Schott (1 sp.), Dieffenbachia Schott (2 spp.), Hapaline Schott (1 sp.), Homalomena Schott (3 spp.), Leucocasia Schott (1 sp.), Philodendron Schott (12 spp.), Phyllotaenium André (1 sp.), Pistia L. (1 sp.), Syngonium Schott (1 sp.), Typhonium Schott (2 spp.), Xanthosoma Schott (1 sp.), and Zamioculcas Schott (1 sp.). The subfamily Lasioideae is represented by a single species of the genus Lasia Lour. The subfamily Lemnoideae consists of two genera (Lemna L. and Wolffia Horkel ex Schleid), each containing one species. The subfamily Monsteroideae includes four genera and five species: Epipremnum Schott (two spp.), Monstera Adans. (one sp.), Scindapsus Schott (one sp.), and Spathiphyllum Schott (one sp.). Finally, the subfamily Pothoideae comprises the genus Anthurium Schott with one species. Additional details on Araceae diversity in Kalasin Province are provided in Table 1, with taxonomic key to the species available in Table S1.

3.2. Distribution of Araceae in Kalasin Province

The habitat occurrence of Araceae species in Kalasin Province is categorized into three groups: wild, cultivated, and those found in both environments. A total of 51 species were documented, with 13 species recorded in the wild and 43 species in cultivation. Among the 13 species recorded in the wild, five species (Alocasia fornicata, Amorphophallus paeoniifolius, Colocasia esculenta, Lemna aequinoctialis, and Wolffia globosa) occurred in both wild and cultivated settings. The remaining eight wild species were exclusively restricted to natural habitats and were not found in cultivation: Amorphophallus brevispathus, Amorphophallus harmandii, Amorphophallus krausei, Amorphophallus lacourii, Hapaline benthamiana, Scindapsus officinalis, Typhonium flagelliforme, and Typhonium trilobatum (Table 1).

The distribution of Araceae across Kalasin’s districts revealed pronounced spatial heterogeneity. Kuchinarai and Mueang Kalasin districts exhibited the highest diversity, each hosting 29 species (Figure 3). This likely stems from a combination of ecological heterogeneity and human activity. These districts may harbor remnant natural habitats alongside agricultural and urban landscapes, facilitating the coexistence of wild and cultivated species.

The distribution of wild Araceae species in Kalasin Province varied notably among districts. Kuchinarai district exhibited the highest number of wild species (six spp.), followed by Somdet (five spp.). In contrast, Kamalasai, Na Khu, and Rong Kham recorded the lowest counts (one sp. each), while most districts reported only two species each (Figure 3). This disparity suggests potential ecological or habitat differences, with Kuchinarai’s higher diversity possibly linked to lower anthropogenic disturbance or more favorable environmental conditions. Notably, Mueang Kalasin and Na Mon, despite being administrative and agricultural hubs, maintained modest wild populations (three spp. each), indicating a balance between urban development and natural preservation.

The distribution of species occurring in both wild and cultivated environments was limited across most districts, with only Yang Talat standing out with three species. Kham Muang and Na Mon followed with two species each, while all other districts reported just one species (Figure 3).

Cultivated Araceae species dominated across all districts, with Mueang Kalasin recording the highest count (27 spp.), followed by Na Mon (25 spp.). Kuchinarai (14 spp.) and Na Khu (15 spp.) had the lowest numbers, likely reflecting differences in agricultural practices, market demand, or access to horticultural resources. Most other districts exhibited intermediate levels (19–24 spp.), indicating moderate cultivation activity (Figure 3). This gradient in cultivation intensity highlights the influence of socio-economic and environmental factors on Araceae distribution in the region.

The distribution of Araceae species in Kalasin Province, as revealed by hierarchical clustering analysis using UPGMA and the Jaccard similarity index, highlights distinct patterns across different districts (Figure 4). The horizontal dendrogram shows that five wild species—Amorphophallus harmandii, A. lacourii, Hapaline benthamiana, Scindapsus officinalis, and Typhonium flagelliforme—form a separate cluster, with most records from Kuchinarai and some from Somdet. This pattern is likely due to the presence of undisturbed forests in these districts, indicating that these species may require relatively intact forest conditions for survival. The heatmap (Figure 4) illustrates that ornamental Araceae species—Alocasia cucullata, A. macrorrhizos, Caladium bicolor, Colocasia esculenta, Dieffenbachia longispatha, D. seguine, Epipremnum aureum, Homalomena pendula, Leucocasia gigantea, Philodendron sp. ‘Burle Marx’, Syngonium podophyllum, and Zamioculcas zamiifolia—are found in all districts, forming a distinct cluster. This reflects their widespread cultivation and adaptability to human-modified environments. Except for Colocasia esculenta, which occurs both as a cultivated and wild species, all others are recorded as cultivated and are not native to Kalasin Province. This highlights the role of human activity in shaping Araceae distribution. The heatmap also indicates that Typhonium trilobatum is the most widely distributed wild species, present in 14 districts. Its broad distribution suggests high ecological plasticity and adaptability to various habitat conditions. The vertical dendrogram (Figure 4) places Kuchinarai as the basal district, with its lower diversity of cultivated Araceae species and higher diversity of wild Araceae species compared to other districts.

3.3. Ecology and Habitat Preferences of Wild Araceae Species in Kalasin Province

Wild Araceae species in Kalasin Province demonstrate pronounced ecological specialization across varied habitats, influenced by the region’s monsoonal climate and substrate heterogeneity. Deciduous and mixed deciduous forests, which host the highest diversity (seven species each), are dominated by geophytic herbs such as Amorphophallus brevispathus, A. harmandii, A. krausei, A. lacourii, A. paeoniifolius, and Hapaline benthamiana (Table 1). These species exploit humus-rich microhabitats on limestone substrates or shaded to semi-shaded forest floors. Wetland-associated habitats (five species) support semi-aquatic geophytes like Colocasia esculenta, Typhonium flagelliforme, and T. trilobatum (although T. trilobatum also grows in mixed deciduous forests), thriving in waterlogged soils along pond margins, rice fields, and ditches. Free-floating aquatics, such as Lemna aequinoctialis and Wolffia globosa, form dense mats in nutrient-rich, stagnant waters. Evergreen and dry evergreen forests harbor fewer species (Alocasia fornicata, Hapaline benthamiana, and Scindapsus officinalis). Alocasia fornicata grows in humus-rich microhabitats on limestone substrates or on shaded to semi-shaded forest floors in evergreen and dry evergreen forests. Scindapsus officinalis, a hemiepiphyte, climbs tree trunks or limestone cliffs after establishing roots in the forest-floor detritus, mostly found in evergreen and dry evergreen forests, but also in mixed deciduous and deciduous forests.

The hierarchical clustering analysis using UPGMA and the Jaccard similarity index reveals distinct ecological specializations among wild Araceae species in Kalasin Province (Figure 5). The horizontal dendrogram (Figure 5) shows that wetland-associated species, including Colocasia esculenta, Lemna aequinoctialis, Typhonium flagelliforme, and Wolffia globosa, form a separate cluster, reflecting their adaptation to aquatic or semi-aquatic environments. The positioning of Typhonium trilobatum as a sister lineage to this cluster suggests habitat plasticity across wetlands and mixed deciduous forests. Additionally, the clustering of Amorphophallus species (A. harmandii, A. krausei, A. lacourii, A. paeoniifolius) indicates overlapping preferences for deciduous and mixed deciduous forests.

The heatmap reinforces these patterns by visually representing the species’ presence across different habitats (Figure 5). The vertical dendrogram (Figure 5) shows that wetland-associated habitats form a sister group to a cluster of mixed deciduous, deciduous, evergreen, and dry evergreen forests, reflecting a clear distinction in species composition. Within this cluster, mixed deciduous and deciduous forests group together, indicating a high degree of species similarity. This mixed cluster is then sister to a separate group containing evergreen and dry evergreen forests, which have fewer species and more specialized habitat requirements.

3.4. Phenology of Araceae in Kalasin Province Under Monsoonal Influence

The phenological patterns of Araceae species in Kalasin Province are strongly influenced by the region’s monsoonal climate, which consists of three distinct seasons: the hot–dry period (March–April), the wet monsoon (May–October), and the cool–dry season (November–February). Flowering activity peaks during the early to mid-monsoon months, with 44 species (86% of the total) flowering between May and August (Figure 6). The highest species diversity in flowering occurs in June (34 species), coinciding with the onset of heavy rains, followed by July (28 species) and August (27 species).

Many geophytes, such as Amorphophallus brevispathus, A. harmandii, A. krausei, A. lacourii, A. paeoniifolius, and Hapaline benthamiana, undergo seasonal dormancy during the hot–dry period (March–April) and the cool–dry season (November–February). These species retreat into subterranean tubers or rhizomes to survive desiccation, resprouting with the monsoon rains and flowering between May and July. In contrast, Lemna aequinoctialis flowers year-round, reflecting its adaptation to stable aquatic habitats buffered from seasonal extremes.

Fruiting lags behind flowering, peaking from August to October (Figure 6), with the highest diversity recorded in October (17 species). This timing corresponds to the period required for fruit and seed maturation. Few species fruit during the dry months (January–April) and the early monsoon months (May–July), with only two to three species fruiting per month, highlighting moisture scarcity as a limiting factor. Notably, 23 out of 51 species exhibited no observed fruiting, likely due to their status as cultivated or non-native ornamentals, which often lack co-evolved natural pollinators in Kalasin’s ecosystems.

3.5. Utilization of Araceae Species in Kalasin Province

The utilization of the 51 Araceae species recorded in Kalasin Province spans six main categories: food, medicine, ornamental purposes, animal fodder, commercial cultivation, and rituals or socio-religious activities. Among these, Alocasia macrorrhizos and Colocasia esculenta are the most extensively used species, contributing to five categories—food, medicine, ornamental purposes, commercial cultivation, and rituals—highlighting their significant cultural and economic value. Additionally, eight species exhibit diverse applications across at least four categories: Aglaonema commutatum, A. costatum, A. modestum, Amorphophallus paeoniifolius, Lasia spinosa, Leucocasia gigantea, Wolffia globosa, and Xanthosoma sagittifolium (Table 1). Each species within this diverse group is utilized in at least one category, spanning six main categories, as detailed in Table 1 and Figure 7 and Figure 8.

3.5.1. Utilization of Araceae as Food

Regarding the utilization of Araceae species as food in Kalasin Province, 13 species from 9 genera have been documented (Table 1 and Table S2). The most commonly consumed plant part is the leaf (41.66%), followed by the inflorescence (33.33%). Stems, including both aerial stems and underground tubers, account for 16.67%, while rhizomes and young leaves each contribute 4.17%. No records indicate the use of roots or seeds as food. The aerial stem of Alocasia macrorrhizos and the underground tubers of Amorphophallus paeoniifolius, Colocasia esculenta, and Xanthosoma sagittifolium are rich in starch and are typically consumed cooked, either as accompaniments or in desserts. The leaf blades and petioles of Amorphophallus brevispathus, A. harmandii, A. krausei, A. lacourii, A. paeoniifolius, Colocasia esculenta, Hapaline benthamiana, Lasia spinosa, Leucocasia gigantea, and Xanthosoma sagittifolium are prepared as vegetables. Similarly, the inflorescences of Amorphophallus brevispathus, A. harmandii, A. krausei, A. lacourii, A. paeoniifolius, Colocasia esculenta, Hapaline benthamiana, and Lasia spinosa are also consumed as cooked vegetables. Additionally, Wolffia globosa, a free-floating aquatic species, is a protein-rich food source consumed either fresh or cooked and is commonly incorporated into traditional dishes and soups. The ripe infructescence of Monstera deliciosa is eaten as a fruit due to its sweet and aromatic flavor.

3.5.2. Utilization of Araceae as Animal Fodder

In Kalasin Province, several Araceae species are utilized as animal fodder, with eight species across eight genera documented (Table 1). The leaves are the most commonly used part, making up 55.56% of the fodder, followed by the entire plant at 33.33%, and inflorescences at 11.11%. There are no reports of roots, fruits, or seeds being used as animal fodder. Specific species such as Alocasia macrorrhizos, Colocasia esculenta, Lasia spinosa, Leucocasia gigantea, and Xanthosoma sagittifolium are fed to pigs. Additionally, aquatic species like Lemna aequinoctialis, Pistia stratiotes, and Wolffia globosa are used as fodder for fish and chickens.

3.5.3. Utilization of Araceae as Herbal Medicine

In Kalasin Province, 10 species of Araceae are utilized as herbal medicine to treat various conditions, with the stem, particularly aerial stems and underground tubers, being the most commonly used part (50%), followed by leaves (35.72%), and infructescences and whole plants (7.14% each) (Table 1 and Table S3). The aerial stem of Alocasia macrorrhizos is used for its anti-inflammatory properties, treating boils and wounds. The underground tuber of Amorphophallus paeoniifolius aids digestion due to its glucomannan content and is used as a diuretic and for treating hemorrhoids and constipation. Colocasia esculenta has antioxidant properties, with its underground tuber and leaves treating skin abscesses and digestive disorders. The leaves of Lasia spinosa exhibit antimicrobial properties, helping with stomachaches and wound healing, while the underground stem and leaves of Leucocasia gigantea serve as an expectorant for coughs and asthma and function as an antiseptic. The infructescence of Scindapsus officinalis is antispasmodic, treating asthma, bronchitis, and digestive issues. Typhonium flagelliforme and T. trilobatum have anti-inflammatory effects, with the former used for general inflammation and the latter for respiratory infections and skin conditions. Wolffia globose is nutrient-rich, aiding in immune support and addressing malnutrition, while Xanthosoma sagittifolium acts as an antioxidant, treating wounds, boils, and digestive problems. In terms of medicinal application, digestive health and skin and wound healing each account for 22.72%, followed by anti-inflammatory uses (18.18%), respiratory health (13.63%), antimicrobial/antiseptic properties (9.1%), and diuretic and immune support benefits (4.55% each) (Figure 9).

3.5.4. Utilization of Araceae as Ornamental Foliage

In total, 40 species from 18 genera are utilized as ornamental plants in Kalasin Province (Table 1). Among the genera, Philodendron is the most represented, with 12 species recorded. Notably, Philodendron sp. ‘Burle Marx’ and Philodendron sp. ‘Lemon Lime’ lack formally published scientific names but are widely recognized in horticulture and the commercial plant trade. The second most diverse genus for ornamental use is Alocasia, with five species recorded, followed by Aglaonema with four species. Commonly cultivated ornamental Araceae in Kalasin Province include Alocasia cucullata, Caladium bicolor, Colocasia esculenta, Dieffenbachia longispatha, Dieffenbachia seguine, Epipremnum aureum, Philodendron sp. ‘Burle Marx’, Syngonium podophyllum, and Zamioculcas zamiifolia. These species are distributed across all districts of Kalasin Province, contributing to the greenery of both urban and rural areas. Their adaptability, ease of cultivation, and ornamental appeal make them integral to local landscapes and horticultural trade.

3.5.5. Utilization of Araceae in Rituals

A fascinating discovery in Kalasin Province has identified 20 species from 13 genera actively cultivated in home gardens, temple gardens, and sacred spaces for their symbolic and spiritual significance (Table 1). These plants are not only admired for their ornamental value but are also believed to possess qualities that align with prosperity, wealth, purification, protection, and renewal.

For example, species like Aglaonema modestum, A. commutatum, A. costatum, A. nitidum, Anthurium hookeri, and Monstera deliciosa are widely cultivated with the intention of attracting good fortune and prosperity. Further enhancing their cultural importance, species such as Alocasia sanderiana, A. cucullata, Caladium bicolor, Dieffenbachia longispatha, D. seguine, Epipremnum aureum, Philodendron sp. ‘Burle Marx’, Philodendron sp. ‘Lemon Lime’, and Zamioculcas zamiifolia are particularly valued for their association with wealth and financial prosperity. The aromatic qualities of Homalomena aromatica and H. pendula contribute to their role in purifying spaces, both physically and spiritually. Spathiphyllum wallisii holds a special place in spiritual practices as a symbol of peace, purity, and harmony. Syngonium podophyllum is another species used in rituals that emphasize transformation and renewal. Lastly, Typhonium trilobatum is highly regarded for its protective properties.

3.5.6. Utilization of Araceae in Commercial Cultivation

In Kalasin Province, the cultivation of Araceae serves as both an economic activity and a means of sustaining traditional agricultural practices, with 43 species from 21 genera recorded as being cultivated for commercial and personal use (Table 1). Of these, 39 species are primarily grown for ornamental purposes. Among them, Colocasia esculenta stands out as an important crop, valued for its carbohydrate-rich tubers, edible leaves and inflorescences, and ornamental foliage.

Additionally, four species are cultivated exclusively for food, contributing to local markets and traditional diets. Amorphophallus paeoniifolius is commercially cultivated for its large underground tubers, which are a staple in various traditional dishes due to their starchy content and nutritional benefits. Lasia spinosa and Leucocasia gigantea are cultivated for their edible leaves and inflorescences, commonly used as vegetables in local cuisine. Wolffia globosa, an aquatic species, is harvested and sold as a vegetable, valued for its high nutritional content.

3.6. Conservation Status and Threats to Wild Araceae in Kalasin Province

The conservation status of wild Araceae in Kalasin Province, as reported on the IUCN Red List Website (IUCN 2025) [34], varies among species (Table 1). Six species are classified as Least Concern (LC). However, seven species remain Not Evaluated (NE), indicating the need for further assessment to determine their conservation status accurately. The absence of evaluation for these species underscores the importance of regional studies to provide updated information for conservation planning.

Following the Guidelines for Using the IUCN Red List Categories and Criteria, Version 16 (March 2024) [35], the conservation status of wild Araceae in Kalasin Province was assessed by the authors (Table 1). Six species—Amorphophallus paeoniifolius, Colocasia esculenta, Lemna aequinoctialis, Typhonium flagelliforme, T. trilobatum, and Wolffia globosa—are proposed as Least Concern (LC) due to their wide distribution and adaptability to disturbed habitats. Five species—Alocasia fornicata, Amorphophallus harmandii, A. lacourii, Hapaline benthamiana, and Scindapsus officinalis—are proposed as Vulnerable [VU B2ab(ii, iv)], as they meet the B2 criterion with an estimated area of occupancy (AOO) of less than 2000 km² and satisfy subcriteria (a) and (b), with (a) their populations being either severely fragmented or occurring in 10 or fewer locations, and (b) an observed or projected continuing decline in both their area of occupancy (ii) and the number of locations or subpopulations (iv) due to habitat degradation and loss. The endemic Amorphophallus brevispathus is proposed as Endangered [EN B2ab(ii, iv)] due to its very limited range, with an estimated area of occupancy (AOO) of less than 500 km², meeting subcriteria (a) and (b), as it is known from four locations and is experiencing a continuing decline in AOO (ii) and the number of subpopulations (iv). Amorphophallus krausei is categorized as Data Deficient (DD) due to insufficient information on its distribution and population trends, highlighting the need for further field studies.

4. Discussion

The present study significantly expands knowledge of Araceae diversity in Kalasin Province, where previous records were limited to Amorphophallus krausei and A. brevispathus [18,23,24]. The documentation of 51 species across 24 genera underscores the province’s rich aroid flora. Notably, this study newly records 11 wild Araceae species for Kalasin Province, a substantial increase from the two species previously reported in the Flora of Thailand [18], and earlier ethnobotanical studies [23,24]. The predominance of subfamily Aroideae, comprising 16 genera and 42 species, aligns with broader patterns in Thailand, where Aroideae is the most diverse group within the family [7,12,18]. These findings highlight the need for continued botanical surveys and taxonomic assessments, as overlooked biodiversity remains to be documented [27].

The distribution of Araceae species in Kalasin Province, as analyzed through hierarchical clustering using UPGMA and the Jaccard similarity index (Figure 4), reveals distinct ecological patterns influenced by both natural and anthropogenic factors. Wild species are predominantly found in districts like Kuchinarai and Somdet, likely due to the presence of undisturbed forests, suggesting their reliance on intact forest ecosystems [23,24,27]. In contrast, ornamental species are widely distributed across all districts, reflecting their adaptability to human-modified environments. This dichotomy underscores the significant role of human activity in shaping Araceae distribution, with cultivated species thriving in anthropogenic landscapes while wild species remain confined to less disturbed habitats [27]. Notably, Typhonium trilobatum stands out as the most widely distributed wild species, indicating its high ecological plasticity and ability to adapt to diverse habitat conditions [18].

Wild Araceae species in Kalasin Province are closely associated with specific habitat types, influenced by monsoonal seasonality. Deciduous and mixed deciduous forests support the highest species diversity, with geophytic species dominating due to their reliance on seasonal dormancy to endure dry conditions. These species retreat into subterranean tubers during the dry season and resprout with the arrival of monsoon rains [18,21]. In contrast, wetland habitats provide stable hydrological conditions essential for aquatic and semi-aquatic Araceae species, which thrive in these environments [38,39].

The phenology of Araceae in Kalasin Province is strongly shaped by the region’s monsoonal climate, with distinct seasonal patterns governing growth, flowering, and dormancy. Geophytic species, which constitute over 70% of wild Araceae, enter dormancy during the dry season and resprout with the onset of monsoon rains. Flowering typically occurs in early to mid-monsoon, ensuring pollinator availability and seed dispersal under favorable conditions. This pattern aligns with findings from previous studies on Zingiberaceae in Kalasin and Saraburi Provinces [27,40].

The conservation status of wild Araceae species in Kalasin Province, based on the IUCN Red List and field assessments, reveals notable discrepancies (Table 1). Many species remain classified as Not Evaluated (NE) on the IUCN Red List [34], highlighting gaps in global assessments. In contrast, field observations and regional assessments provide a more comprehensive understanding of conservation priorities. Despite the province’s rich Araceae diversity, multiple threats jeopardize species survival. Agricultural expansion is a primary concern, leading to habitat loss and fragmentation as forests are converted to farmland [22]. Urbanization and deforestation further contribute to population declines, particularly for species restricted to forest understories [22]. Overexploitation is another major threat, particularly for Amorphophallus brevispathus and Hapaline benthamiana, which are harvested for food [23,24]. To mitigate these threats, detailed population assessments are necessary for species lacking IUCN evaluations [35].

This study advances understanding of Araceae utilization in Kalasin Province by documenting their diverse applications. Previous research was limited to the use of Amorphophallus brevispathus as a food source [23,24]. This study expands upon that by highlighting the nutritional value of Amorphophallus paeoniifolius and Colocasia esculenta, which provide starch-rich tubers, and Wolffia globosa, a high-protein aquatic species [41]. These findings align with global studies on the nutritional potential of Araceae, such as the role of Colocasia esculenta as a staple food in tropical regions [42]. However, proper preparation methods—such as boiling, steaming, or fermenting—are necessary to neutralize calcium oxalate crystals, which are toxic if consumed raw. This aligns with previous research on the toxicity of Araceae species and traditional knowledge in mitigating health risks [43].

The use of eight Araceae species as animal fodder demonstrates their role in supporting livestock nutrition. This finding is consistent with studies from other regions where Araceae species, such as Colocasia esculenta, are valued as animal feed due to their high nutrient content [44]. Medicinal applications of Araceae in Kalasin Province are particularly noteworthy, with ten species used to treat various ailments. This finding resonates with studies from other regions where Araceae species have been documented for their anti-inflammatory, antimicrobial, and antioxidant properties [43,45,46]. However, the specific uses and preparation methods documented in this study provide novel insights into the traditional health practices of Kalasin Province. This study also highlights the extensive use of Araceae in ornamental horticulture, with 40 species across 18 genera cultivated for their aesthetic appeal. This aligns with global trends in ornamental horticulture, where Araceae species are prized for their unique growth forms and decorative value [47]. The broad spectrum of Araceae utilization underscores their ecological, cultural, and economic significance in Kalasin Province, highlighting their role in sustaining livelihoods and traditional practices.

5. Conclusions

The present study provides a comprehensive assessment of the diversity, utilization, and conservation status of Araceae in Kalasin Province, significantly expanding the known records for the region. The documentation of 51 species across 24 genera highlights the province as an important center of aroid diversity, with a predominance of the subfamily Aroideae. The discovery of previously unreported species underscores the need for continued botanical exploration and taxonomic studies to fully capture the region’s biodiversity.

Araceae species in Kalasin Province display distinct distribution patterns influenced by habitat type, ecological conditions, and human activity. While wild species predominantly occupy forested and wetland environments, cultivated species thrive in urban and agricultural landscapes, reflecting both natural adaptations and human-mediated dispersal. The strong association of geophytic taxa with monsoonal seasonality further illustrates the role of climatic factors in shaping the phenology and survival strategies of these species. Despite their ecological significance, wild populations face conservation challenges due to habitat loss, agricultural expansion, and overharvesting. Species with restricted distributions are particularly vulnerable to habitat fragmentation. Targeted conservation measures, including habitat protection, sustainable harvesting, and ex situ conservation, are essential for safeguarding these species.

The diverse utilization of Araceae species underscores their economic, cultural, and ecological importance. As food, animal fodder, and medicinal resources, these species contribute significantly to local livelihoods and traditional practices. Additionally, their role in ornamental horticulture, ritualistic applications, and commercial trade further highlights their widespread value. However, sustainable management is necessary to balance utilization with conservation, ensuring the long-term viability of these resources. Overall, this study emphasizes the rich Araceae biodiversity in Kalasin Province and its multifaceted significance. Strengthening conservation policies, promoting sustainable use, and fostering public awareness are crucial for preserving these species and their associated ecosystems. Continued research and conservation efforts will be key to maintaining the ecological and economic benefits provided by Araceae in the region.