[Ichthyology • 2025] Barbucca heokhuii • A New Species of loach (Teleostei: Barbuccidae) from central Borneo

 Barbucca heokhuii

 Kottelat, 2025

 

Raffles Bulletin of Zoology. 73; 

Abstract

 Barbucca heokhuii, new species, is described from the Kahayan drainage in central Borneo. It is distinguished from the other species of the genus by its miniature size (the largest known specimen is 21.5 mm SL), a truncate to rounded caudal fin, an incomplete lateral line, and a distinctive colour pattern made, among others, of five pairs of irregular bars on the flank, narrower than interspaces, many of which may be dissociated into several small blotches. It occurs in syntopy with B. diabolica. Sexual dimorphism is reported for the first time for a member of the family; in males, the 2nd to 4th branched pectoral rays are thicker than the others and with a patch of small tubercles along their posterior edge. 

Key words. Cobitoidei, loach, miniature fish, sexual dimorphism, black water, peat swamp forest

 Barbucca heokhuii, ZRC 66766, 16.2 mm SL; Borneo, Kalimantan Tengah: Kahayan drainage.

(Photographs by Tan H. H.).

Barbucca heokhuii, new species  

 Diagnosis. Barbucca heokhuiiis distinguished from the other named species of Barbucca by having: a smaller adult size (the largest known specimen is 21.5 mm SL, vs. 37.2 in B. diabolica and 34.3 in B. elongata), a deeper body (depth at dorsal-fin origin 17–21 % SL, vs. 14–18 in B. diabolica and B. elongata); a truncate to rounded caudal fin (vs. emarginated); the lateral line incomplete, reaching to below posterior half of dorsal fin (vs. complete); absence of large tubercles on head and body (vs. presence on posterior part of flank, between above the tip of the pelvic fins and the base of the caudal fin); anus about halfway between pelvic-fin base ...

Etymology. Named for Tan Heok Hui (LKCNHM) in appreciation for his work on Southeast Asian fishes, and especially fishes of peat swamp forests and loaches of Borneo, and for the long lasting friendship, collaboration and companionship in the field. 

MAURICE KOTTELAT. 2025. Barbucca heokhuii, A New Species of loach from central Borneo (Teleostei: Barbuccidae). Raffles Bulletin of Zoology. 73; 54–66.

 Researchgate.net/publication/389338300_Barbucca_heokhuii_a_new_species_of_loach_from_central_Borneo

[Ichthyology • 2025] Sewellia pudens • A New Species of loach (Cypriniformes: Gastromyzontidae) from Dakchung Plateau, southern Laos

Sewellia pudens  

Kottelat, 2025

 

 Raffles Bulletin of Zoology. 73; 

Abstract

 Sewellia pudens, new species, is described from the Xe Kaman watershed on Dakchung Plateau, Sekong Province, southern Laos. It is distinguished from other species of the genus in having a yellowish brown body; no markings on the fins; in males, a patch of tubercles on the snout divided longitudinally by a deep groove; no modified pelvic-fin rays with dorsal bone extension. The mouth of Sewellia and the tubercles and ornamentation on the fins of several species are described; the ‘pelvic valve’ is figured. 

Key words. Cobitoidei, loach, pectoral fin, pelvic fin, tubercles, bony extensions

Sewellia pudens, MHNG 2799.022, holotype, 49.2 mm SL, male; Laos: Xe Kaman watershed, Dakchung Plateau. Tip of axillary pelvic lobe on left side damaged.

Sewellia pudens, new species

 

Diagnosis. Sewellia pudens is distinguished from all species of Sewellia by the poorly developed patterning of the body and fins. On the body, black pigments are present in a vague midlateral stripe and 3–8 small saddles on the back, especially on caudal peduncle. Some irregular markings are also present on the body of some specimens, but not forming a clear pattern. The fins of most specimens have no colour marks, except for thin black lining along rays in the dorsal, anal and caudal fins, and, rarely, 1 or 2 faint blotches along lower edge of the caudal fin. The pectoral and pelvic fins ...

Etymology. The Latin adjective ‘pudens’ means modest, humble, reserved, discreet. It refers to the absence of conspicuous pattern on the body and fins (compared to most other species of the genus) and the absence of ostentatious modification on pectoral- and pelvic-fin rays. Pudens is indeclinable.

MAURICE KOTTELAT. 2025. Sewellia pudens, A New Species of loach from Dakchung Plateau, southern Laos (Teleostei: Gastromyzontidae). Raffles Bulletin of Zoology. 73; 304–317.

[Herpetology • 2025] Dixonius noctivagus • A New Species of Dixonius (Squamata: Gekkonidae) from A Karstic Archipelago in Western Cambodia

 

Dixonius noctivagus 

L. L. Grismer, Sinovas, Quah, Thi, Chourn, Chhin, Hun, Cobos, Ching, Murdoch, Gregory, Nguyen, Hernandez, Kaatz & J. L. Grismer, 2025

Battambang leaf-toed gecko || DOI: doi.org/10.11646/zootaxa.5653.4.3

 

Abstract

An integrative taxonomic analysis was used to delimit and diagnose a new species of Dixonius from a karstic archipelago in western Cambodia. Dixonius noctivagus sp. nov. was recovered as the sister species to an undescribed species from eastern Cambodia and southwestern Vietnam based on 1,396 bp of the mitochondrial ND2 gene. A statistically robust diagnosis was established through multivariate and univariate analyses of morphometric, meristic, and categorical color pattern characters separating D. noctivagus sp. nov. from all other congeners. Although Dixonius is a common and widespread genus, the description herein brings the total number of Dixonius in Cambodia to two—far fewer than the eight species from both neighboring Thailand and Vietnam. This disparity underscores the need for systematic biodiversity surveys in the many understudied regions of Cambodia, particularly focusing on its herpetofauna. The discovery of D. noctivagus sp. nov. alongside recently described Cyrtodactylus and Hemiphyllodactyus species from the same karst formations highlights the urgent need for legal protection of these fragile habitats in the region.

Reptilia, conservation, Gekkota, genetics, integrative taxonomy, limestone, phylogeny, Southeast asia

 Dixonius noctivagus sp. nov.

Battambang leaf-toed gecko 

L. Lee GRISMER, Pablo SINOVAS, Evan S. H. QUAH, Sothearen THI, Phyroum CHOURN, Sophea CHHIN, Seiha HUN, Anthony COBOS, Christian CHING, Matthew L. MURDOCH, Jeren J. GREGORY, Eddie NGUYEN, Alexis P. HERNANDEZ, Amanda KAATZ and Jesse L. GRISMER. 2025. A New Species of Dixonius Bauer, Good, & Branch, 1997 (Squamata: Gekkonidae) from A Karstic Archipelago in Western Cambodia. Zootaxa. 5653(4); 501-523. DOI: doi.org/10.11646/zootaxa.5653.4.3 [2025-06-30]

[Botany • 2025] Paphiopedilum motuoense (Orchidaceae: Cypripedioideae) • A New Species from Motuo, Xizang, China

Paphiopedilum motuoense  M. N. Wang, F. X. Tang & W. H. Rao,

in Tang, Rao,  Zhang, Wu, M. Wang, Li, Chen, Duan et M.-N. Wang. 2025. 

墨脱兜兰  ||  DOI: doi.org/10.3897/phytokeys.259.145861 

 Abstract

Paphiopedilum motuoense, a newly discovered orchid from Motuo County, Xizang, China, is described and illustrated. Paphiopedilum motuoense can be distinguished from the related Paphiopedilum species P. qingyongii and P. venustum by several distinctive features: a significantly smaller staminode above the column, a distinct purplish-red lip with purplish-brown veins, pouched with erect and triangular auriculas on both sides of its mouth, and leaves with pale green and pale yellowish-green tessellations. The novelty is also well supported as a new species by molecular phylogenetic analysis. Additionally, the complete chloroplast genome of P. motuoense, 157,218 bp in length, was assembled and annotated. It contains an LSC region of 86,275 bp, SSC region of 949 bp and two IRs of 34,997 bp, with 120 genes, including 76 PCGs, 36 tRNA genes and 8 rRNA genes.

Key words: China, new orchid species, Paphiopedilum motuoense, plastid genome

Paphiopedilum motuoense and its allies
a1–d1 Paphiopedilum motuoense a1 whole plant b1 leaf c1 flower d1 staminode.
a2–d2 P. venustum a2 whole plant b2 leaf c2 flower d2 staminode.
a3–d3 P. qingyongii a3 whole plant b3 leaf c3 flower d3 staminode.

Images of living plants of Paphiopedilum motuoense 
A whole plant B, C flower (side view and back view) D, E dorsal sepal (front view and back view) F, G synsepal (front view and back view) H, I petal (front view and back view) J–L lip (front view, side view and back view) M lip (vertical section) N ovary and column (with bract, synsepal and staminode) O–Q column (back view and side view) R, S staminode (front view and back view).

Paphiopedilum motuoense
  A whole plant B, C flower (side view and back view) D, E dorsal sepal (front view and back view) F, G synsepal (front view and back view) H, I petal (front view and back view) J–L lip (front view, side view and back view) M lip (vertical section) N ovary and column (with bract, synsepal and staminode) O–Q column (back view and side view) R, S staminode (front view and back view).

 Paphiopedilum motuoense M. N. Wang, F. X. Tang & W. H. Rao, sp. nov.

  Chinese name. 墨脱兜兰

Diagnosis. Paphiopedilum motuoense is similar to P. venustum and P. qingyongii in morphology, but differs from them by having a smaller staminode, petals flushed with purplish red, a purplish red lip with purplish brown veins, pouched with erect and triangular auriculas on both sides of mouth, and leaves adaxially tessellated with pale green and pale yellowish green (Table 1, Fig. 1).

Feng-Xia Tang, Wen-Hui Rao, Ze Zhang, Xin-Yi Wu, Meng Wang, Jian Li, Jie-Shan Chen, Xiao-Juan Duan and Mei-Na Wang. 2025. Paphiopedilum motuoense (Orchidaceae, Cypripedioideae), A New Species from Motuo, Xizang, China. PhytoKeys. 259: 131-144. DOI: doi.org/10.3897/phytokeys.259.145861