Colocasia sookchaloemiae (Araceae) is described from Phu Pha Yol National Park (northeastern Thailand). It is morphologically similar to C. fallax , from which it differs in having seasonal dormancy (vs. evergreen), broader and non-glaucous laminae (vs. narrower and slightly glaucous beneath), a speckled green ovary (vs. mostly green), a convex stigma with a depressed center (vs. 3-lobed), a sparsely hairy sterile interstice (vs. glabrous), and a thicker stipitate appendix (vs. slender, often sessile, or shortly stipitate). A comparative study of living plants, cultivated specimens, and herbarium material (including types) supports its recognition as a distinct species. The new taxon grows on rocky cliffs in dry dipterocarp and mixed deciduous forests at 350–400 m a.s.l., and it is currently known from Mukdahan and Sakon Nakhon provinces. A preliminary IUCN assessment indicates that the species is Data Deficient (DD).

A new subspecies, Ardisia crenata Sims subsp. mukdahanensis Chatan & Promprom (Primulaceae), is described from Mukdahan Province, Thailand. This discovery was made during field studies conducted from 2021 to 2023, during which the authors collected and analysed specimens, comparing them with relevant taxonomic literature and herbarium collections. A. crenata subsp. mukdahanensis is distinct from its closest relative, A. crenata subsp. crassinervosa by a combination of morphological traits, such as moderately dense minute hairs on young shoots, abaxial side of young lamina and calyx, peduncles and pedicels; larger flowers (7.0–7.5 mm) that are pure white or pinkish; larger fruits (7–8 mm) and absence of glandular punctation in organs such as lamina, calyx, corolla, anther and fruit. This new subspecies grows in slightly dense dry evergreen forests or open areas near streams and is preliminarily assigned to the Data Deficient (DD) category according to IUCN guidelines.

The effects of dietary supplementation of spray-dried hog plum (Spondias pinnata (L.f.) Kurz) fruit powder (SPP) on growth, digestive enzyme activity, and skin mucus immune parameters of climbing perch (Anabas testudineus (Bloch, 1972)) were examined. The fish (N = 330; 2.00±0.1 g) were assigned to five groups in triplicates. They were fed different SPP levels at 0, 5, 10, 15, and 20 g/kg diet for eight weeks. Flavonoids, terpenoids, phenolic compounds, tannins, steroids, glycosides, and glycosides were detected in SPP. The SPP containing diet significantly improved growth parameters (P < 0.05) without a negative effect on the survival rate (P > 0.05). Intestinosomatic and hepatosomatic indices significantly declined in the fish fed SPP added diets (P < 0.05). There were significant elevations in digestive enzyme activities, amylase, protease, lipase, trypsin, pepsin, and esterase, in the tested fish compared to the control fish (P < 0.05). Additionally, fish fed SPP containing diets showed a significant enhancement of total protein, immunoglobulin M, lysozyme, antiprotease, alkaline phosphatase, and esterase in the skin mucus compared to the control group (P < 0.05). Significantly higher levels of superoxide dismutase, catalase, and total antioxidant capacity were detected in fish fed SPP containing diets compared to the control (P < 0.05). These findings suggest that dietary SPP supplementation can effectively enhance fish growth, digestive enzyme activities, and mucosal immune parameters in the climbing perch. The suitable level of SPP observed in this present study was 13.00 – 15.88 g/kg diet.

Pycnospatha is a small and poorly known genus of Araceae distributed in Indochina and currently comprising only two accepted species. During botanical surveys in Si Sa Ket Province, eastern Thailand, an unusual population of Pycnospatha was discovered in a dry dipterocarp forest and found to differ from both P. arietina and P. palmata. Here, we describe this plant as a new species, Pycnospatha phanomdongrakensis. The new species is distinguished by a combination of characters, including a slender habit, shorter petiole and peduncle, a medium-sized spathe, a short and dense spadix, a distinctly curved style directed toward the apex of the spadix, a geophilous and ovoid infructescence, obovate berries, and asymmetrically ovoid seeds. The new taxon is currently known only from a single population in the Phanom Dong Rak mountain range. A preliminary conservation assessment is provided, and the species is treated as Critically Endangered (CR) following IUCN guidelines. An identification key to all species of Pycnospatha is also presented. The discovery of this new species highlights the continuing importance of field-based taxonomy in revealing overlooked aroid diversity in the seasonally dry forests of eastern Thailand.

Fisheries and Aquatic Sciences

Typhonium is one of the most species-rich genera of Araceae in tropical Asia, with north-eastern Thailand representing an important but still incompletely documented area of diversity. During botanical surveys in northeastern Thailand, an unusual population of Typhonium was discovered in mixed deciduous forest and dry evergreen forest at 300–400 m elevation. Detailed morphological study of living plants and herbarium specimens, together with comparisons with relevant protologues, regional floras, and recently described species, confirmed that this population represents a species new to science. It is here described as Typhonium mukdahanense Chatan & Promprom, sp. nov. The new species is morphologically most similar to T. fornicatum, but differs by its taller habit, larger hastate to trisect leaf blades, more numerous primary lateral veins, larger and nearly symmetrical spathe tube, triangular reflexed spathe limb, dark red stigma with a cream-colored depressed center, sterile interstice bearing 10–14 staminodes arranged in two whorls, slightly curved and not spreading–declinate appendix, and pyriform mottled berries. It also differs from T. acetosella by its broader leaf blades, reflexed triangular spathe limb, dark red stigma, and pyriform fruits. The new species is currently known only from the type locality and is therefore provisionally assessed as Critically Endangered (CR) according to the IUCN Red List Categories and Criteria. A detailed description, diagnosis, information on distribution, habitat, phenology, conservation status, and an identification key to morphologically similar species are provided.