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Special Volume of International Symposium of Tropical Fish Ecological Conservation and Biodiversity 2025 (ISTFECB 2025) Part I—Systematics, taxonomy, and species diversity of tropical fishes (Title page)

CHIH-WEI CHANG — 2025-12-30

Special Volume of International Symposium of Tropical Fish EcologicalConservation and Biodiversity 2025 (ISTFECB 2025) Part I—Systematics, taxonomy, and species diversity of tropical fishes (Table of contents)

CHIH-WEI CHANG — 2025-12-30

Preface: Special Volume of International Symposium of Tropical Fish Ecological Conservation and Biodiversity 2025 (ISTFECB 2025) Part I—Systematics, taxonomy, and species diversity of tropical fishes: contributed papers from ISTFECB 2025

CHIH-WEI CHANG — 2025-12-30

**A new species of dwarf goby of Trimma (Teleostei: Gobiidae) from Taiping Island, South China Sea**

CHIH-WEI CHANG — 2025-12-30

A rare coral-reef dwarf goby was collected recently from Taiping Island, South China Sea. The new species, Trimma taipinensis, can be well distinguished from other congeners by the following unique combination of features: (1) fin ray counts D2 I/7, A I/7, P 17, V with complete sucking disc; (2) squamation including LR 29–30, TR 9, SDP 9, PreD 7, opercle with large scales; (3) no any canal pores; and (4) distinctive colouration: body pale white background with lower half entirely orange yellow. Three cross bands in front of first dorsal fin origin; seven major vertical crossing bands after origin of first dorsal fin. Head with one red bar crossing snout to both jaws, another one vertical red stripe below eye, a vertical red band crossing the edge of preopercle. Nape with two orange red bands. Pectoral fin pinkish to orange, its basal region with two rounded snow white marks. Caudal fin entirely pinkish orange. No any black blotch on caudal fin base. A brief comparison with related species will also be provided.

Lepusigobius, a new generic name proposed for Gobiosoma pallida Herre, 1934 (Gobiiformes: Gobiidae) from west Pacific with re-description of the species

TOSHIYUKI SUZUKI — 2025-12-30

In this study, after examining new additional materials and data collected from type materials, we designate a new gobiid genus, Lepusigobius, for Gobiosoma pallida Herre, 1934, a species that has a perplexing taxonomic history. Lepusigobius can be initially characterized by having a reduced transverse neuromast organ arrangement, a rabbit-like notched upper lip, and a dorsal pterygiophore formula of 3-12210. Other morphological diagnostic characters of Lepusigobius include the body moderately elongated, totally naked, pelvic fins with fully developed connecting membrane and frenum, and both dorsal fins connected basally. Descriptions of head lateral line system configurations and both fresh and preserved colourations are given, and a comprehensive comparison of Lepusigobius with other related genera are also provided herein.

**A new species of Luciogobius Gill (Teleostei: Gobiidae) from northern Taiwan**

CHIH-WEI CHANG — 2025-12-30

A new gobiid fish of Luciogobius Gill, 1859 had recently been collected from the intertidal waters of northern Taiwan. The new species, Luciogobius delicatus sp. nov., is characterized by the following unique combination of features: (1) second dorsal fin rays: I/10 and anal fin rays I/12; (2) pectoral fin rays 14 and with one upper, short free soft ray; (3) vertebral count: 22 + 22 = 44; and (4) specific coloration: body and head rather light, creamy yellow. Pectoral fin base with several tiny black spots. Caudal fin pale brown. Second dorsal fin translucent with tiny black dots. A brief discussion of their own related species would also be addressed.

A new wriggler of Eleotrid (Teleostei: Xenisthmidae) from Taiping Island, South China Sea

CHIH-WEI CHANG — 2025-12-30

A new wriggler of genus Xenisthmus was collected from Taiping Island, South China Sea, Taiwan, while SCUBA diving for a coral reef fish survey. The new species, Xenisthmus aureus sp. nov., can be well distinguished from other congeners by the following unique combination of features: (1) fins: second dorsal fin rays I/11; anal fin rays I/10; pectoral fin rays15; (2) squamation: longitudinal scale series 60–62; perdorsal scales 0; (3) vertebral count 10+16=26; (4) preopercular canal present with 4 pores γ, δ, ε, and ε1; and (5) specific colouration: lateral side of trunk with an upper horizontal series of 20–22 yellow spots; a median series of oblique golden yellow stripes or becoming smaller, irregular golden yellow marks; the orange red cross mark on eye, radiating into mouth and posterior area horizontally, and extending up to top eye margin to downward vertically behind the maxillary on cheek; pectoral fin base with a upper, large oblique golden yellow mark; and caudal fin base with a very small median black spot. A species comparison of other congeners will also be briefly discussed in this paper.

**A new dwarf goby of genus Eviota (Teleostei: Gobiidae) from northern Taiwan**

I-SHIUNG CHEN — 2025-12-30

A new dwarf goby of genus Eviota was found and collected via SCUBA diving from northern Taiwan. The new species, Eviota bifurca sp. nov. can be well distinguished from other congeneric species by the unique combination of following features: (1) second dorsal fin I/8, anal fin I/8, pectoral fin 16; (2) longitudinal scale rows 24–25; (3) typical head canal pattern in lacking posterior oculoscapular canal and preopercular canal; (4) mouth large, extending to middle vertical of eye; and (5) specific coloration: body and head creamy white. Each scale pocket with golden yellow to yellowish brown margin. Ventral profile after anus with 5 major inner blackish brown blotches. Snout pointed with a bright orange stripe crossing to both lips. Two somewhat vertical orange lines below orbit. Totally trunk after first dorsal fin origin with 9 dorsal inner marks. First dorsal fin translucent with a basal forked brown mark. Basal region of first dorsal fin with three inner brown marks. Second dorsal fin translucent with 4–5 longitudinal rows of brown spots. Basal region of second dorsal fin also with three inner brown marks. Pectoral fin base with an upper orange round spot. Caudal fin base with a vertical brown bar. A brief morphological comparison with congeners will also be addressed.

**A newly recorded species of dwarf gobiid genus, Eviota (Teleostei: Gobiidae) from northern and eastern Taiwan**

MING-FON YEH — 2025-12-30

A newly recorded species of dwarf gobiid genus, Eviota (Teleostei: Gobiidae) was recently collected from the coastal waters of northern and eastern Taiwan. The new record of Eviota species from Taiwan is identified as Eviota perspicilla Fujiwara, Suzuki & Motomura, 2020, which was regarded as endemic to Japan. A brief redescription and the remarks are also provided in this paper.

**Two new species of marine goby genus Trimmatom (Teleostei: Gobiidae) from Taiwan, southeastern Asia with comments on a newly recorded species**

TONISMAN HAREFA — 2025-12-30

Two new species of marine goby of the genus Trimmatom Winterbottom & Emery, 1981 are described from coastal waters of Taiwan. Trimmatom novempunctatus sp. nov. is distinguished from all congeneric species by the following unique combination of features: second dorsal fin rays 8–10; anal fin rays 8–9; pectoral fin rays 13–14; longitudinal scale rows 23; transverse scale rows 5; and pelvic fins with the first to third rays each branched once, the fourth ray elongated posteriorly (reaching beyond the last ray of the anal fin) and the fifth ray 6–10% as long as the fourth; distinctive colorations: the dorsum has a medial row of 9 dark spots extending from the first dorsal fin to the upper procurrent caudal fin, and the ventral side of the body has a medial row of 5 dark spots between the anal fin origin and the end of the caudal peduncle. Trimmatom tetramaculatus sp. nov. is similarly distinguished by its unique combination of features: second dorsal fin rays 9; anal fin rays 9; pectoral fin rays 18; longitudinal scale rows 23; transverse scale rows 6; and pelvic fin with the first to fourth rays branched and the fourth ray short; distinctive colorations: a short, light-purplish blue band on both sides of the upper opercle (discontinuous across the nape); and four light-purplish blue saddles along the body’s upper side. A new distributional record for Taiwan of another member of this genus, Trimmatom pharus Winterbottom, 2001, is also documented. A brief comparison of related congeneric species will also be addressed.

Trimma novemstriatum, a new species of marine goby fish (Teleostei: Gobiidae) from Taiwan

TONISMAN HAREFA — 2025-12-30

A new species of pygmy goby of the genus Trimma Jordan & Seale, 1906 was described based on the specimens collected from the coastal water of northern and southeastern Taiwan. Trimma novemstriatum sp. nov., can be distinguished from its congeners by the following unique combination of features: (1) fin ray counts of second dorsal fin I/9, anal fin I/8, and pectoral fin 17, with the pectoral fin rays and 5th pelvic fin ray unbranched; (2) squamation including longitudinal scale rows 22–23, transverse scale rows 6–7, scales between first dorsal fin to upper margin of pectoral fin base 3, no scales on the cheek and operculum, side area of predorsal scales usually present; (3) number of papillae on cheek rows b and d usually 4–5; and (4) distinctive colouration with the dorsum crossed by 9 yellowish-orange stripes or saddles, the midside of the body with 9 vertical stripes connected to lower spot of the belly to caudal peduncle, 1^st to 3^rd of which separated from dorsal but all others partly or fully connected to saddles.

First specimen-based record and preliminary assessment of the fisheries status of Otolithoides pama (Hamilton, 1822) (Perciformes: Sciaenidae) from the West Coast of Peninsular Malaysia, Strait of Malacca

NORHAFIZ HANAFI — 2025-12-30

Otolithoides pama (Hamilton, 1822), commonly known as the pama croaker, is reported here from the west coast of Peninsular Malaysia based on recent specimens collected during ichthyofaunal surveys in Bagan Datuk, Perak (January 2024; n = 1) and Muar, Johor (June 2019; n = 3 and April 2025; n = 8). This represents the first voucher specimen-based distributional record of the species in Malaysian waters, where no locally deposited specimens have previously been documented. Historically, five preserved specimens of O. pama have been held in overseas institutions since 1922, highlighting a century-long gap in local representation. The species is widely distributed across the Bay of Bengal, from Pakistan and India to Bangladesh and Myanmar, with recent records extending to the Andaman Sea (Thailand). The twelve newly collected Malaysian specimens, including one juvenile and seven pre-adults (standard length 158–325 mm), suggest possible dispersal into the Strait of Malacca via the East Indian Ocean Current. Diagnostic features include a large body, small eyes, conical snout, large terminal mouth, short and weak second anal spine, and a pointed caudal fin. Morphometric and meristic analyses are provided, along with a phylogenetic tree based on the mitochondrial COI gene, supporting the monophyly of the species with observed intraspecific variation. This study marks a significant update to the known distribution of O. pama and contributes to the national ichthyological records with the first locally curated specimens.

The updated checklist of marine fishes in the waters of South Penghu Marine National Park, Taiwan

HAN-YANG LIN — 2025-12-30

This study presents a comprehensive survey of marine fish diversity within the South Penghu Marine National Park, Taiwan, conducted from 2017 to 2021. Utilizing visual stripe-transect methods, synthesis of existing literature, and rigorous taxonomic validation, we documented 572 marine fish species from 74 families, including one new and one newly recorded gobiid species, significantly exceeding previous regional surveys. Labridae, Pomacentridae, Gobiidae, and Epinephelidae dominated species richness. Spatial heterogeneity was evident, with Dongjiyu exhibiting the highest diversity (425 species). A substantial proportion of species (31.8%) were site-specific, highlighting habitat variability and the importance of maintaining connectivity. The increased species richness likely reflects the park’s establishment in 2014, enhancing ecosystem recovery and protection. The park’s role as a buffer against environmental disturbances, such as cold-water events, emphasizes its importance in safeguarding biodiversity. This study provides an updated baseline for ichthyological resources, informing conservation and management strategies for this valuable marine ecosystem.

**A new pygmy goby of genus Trimmatom (Teleostei: Gobiidae) from Lanyu Island, Taiwan**

I-SHIUNG CHEN — 2025-12-30

The new pygmy goby of genus Trimmatom was found and collected from Lanyu Island off Taiwan via SCUBA diving. The new species, T. lanyuensis, can be well distinguished from other congeneric species by the unique combination of the following features: (1) fin rays: second dorsal fin rays 10, anal fin rays 10, pectoral fin rays 21; (2) squamation: longitudinal scale rows 27–28 (modally 27), predorsal naked; and (3) specific coloration: head and body with greyish brown background bearing bloody red marks. Lateral body with pale gray 5 vertical bars, anterior 4 longer extension to ventral side, the last one shorter passing less than only half way of lateral side against the red body. Head generally with entirely gray in cheek. Opercle with two red vertical lines. The two red lines interrupted to dorsal two cross red bars. Caudal fin pinkish red, with basal region bloody red. Pectoral fin bloody red with basal central red mark. A brief comparison of related congeneric species will also be addressed.

**New records of two flap-headed gobies of genus Callogobius (Gobiiformes: Gobiidae) from Taiwan with an updated artificial key of Taiwanese congeners**

HSIEN-EN LI — 2025-12-30

Herein, we give vouchered new records upon two Callogobius from Taiwan; they are C. shunkan Takagi, 1957 and C. stellatus McKinney & Lachner 1978b. These records represent the southward and northward extension of the species’ previous geographical distribution, respectively. Detailed descriptions of their morphology, sensory canal and papillae patterns, and fresh colorations are given, and an artificial dichotomous key to all 11 Callogobius species is also provided to aid in related research.

**New records of six combtooth blennies in the genera Blenniella, Cirripectes, Istiblennius, and Salarias (Perciformes: Blenniidae) from Taiping Island, South China Sea**

YU-JIE ZHAO — 2025-12-30

The family Blenniidae comprises 59 genera and 413 valid species worldwide, of which 25 genera and 69 species are recorded from Taiwan. Previous work documented 11 species of blennies from Taiping Island, Nansha Islands, South China Sea but subsequent ichthyofaunal surveys conducted in May–June 2024–2025 using clove oil and hand nets in intertidal tidepools, shallow rocky reefs, and seagrass habitats yielded additional, previously unrecorded taxa. Here we report Blenniella chrysospilos, B. periophthalmus, Cirripectes variolosus, Istiblennius dussumieri, I. lineatus, and Salarias fasciatus from Taiping Island, based on detailed morphometric and meristic data supported by X-ray examinations. Diagnostic characters, live coloration, and habitat information are provided for each species, thereby refining the blenniid fauna of Taiping Island and expanding knowledge of blenny diversity in southern Taiwanese waters.

**Additional description and geographic distribution of the splitfin ocean-bass Synagrops atrumoris from southwestern Taiwan**

YU-SHAN HUANG — 2025-12-30

The splitfin ocean-bass Synagrops atrumoris belonging to the Family Synagropidae is newly recorded from Dong-gang Fishing Port, Pingtung County, southwestern Taiwan. In this study, we expand the geographical distribution and provide a series of detailed additional dental and osteological descriptions of this species. Fresh color photographs, radiographs, the description of the structure of the proximal-middle radial of the first anal-fin pterygiophore, dentition illustration of this specimen, and comparisons with the congener S. japonicus are also provided herein.

**First regional record of two Mugilogobius Smitt (Gobiiformes: Gobiidae) from Penghu (Pescadores Islands), Formosan Strait**

HSIEN-EN LI — 2025-12-30

During an investigation of the freshwater crustacean fauna of Penghu Island, we collected Mugilogobius cavifrons (Weber, 1909) and Mugilogobius chulae (Smith, 1932). These species represent the second and third additions of Mugilogobius species diversity in Penghu and an addendum to their respective species distribution in the Formosan Strait. Herein, we give detailed descriptions of their morphology, sensory canal and papillae patterns, and fresh colorations and comparisons of the two species with their relatives on the adjacent island of Taiwan.

**A new species of shrimp-goby genus Cryptocentrus (Teleostei:Gobiidae) from the Philippines**

I-SHIUNG CHEN — 2025-12-30

A new marine shrimp-goby of the genus Cryptocentrus was collected from the coastal waters of Luzon, the Philippines. This new species, Cryptocentrus aureostriatus sp. nov., can be well distinguished from other congeneric species by the following unique combination of features: (1) second dorsal fin I/11; anal fin I/10; pectoral fin 16; (2) squamation: longitudinal scale rows 60–62; transverse scale rows 24; predorsal scale rows 17; (3) normal vertebral count 26; and (4) colouration in life: body generally creamy yellow, body with about eight major brown cross-bars; nape with two brown major bars; caudal fin base with a deep, vertical brown bar; head with three major oblique, parallel golden yellow stripes; snout tip with one short orange bar; the posterior tip of opercle with one yellow mark; first dorsal fin with three major oblique yellow stripes; second dorsal fin translucent with several yellow stripes; anal fin creamy yellow to pale white and unmarked. A description of the new species and a brief comparison with related species in the Indo-Pacific region will be reported in this paper.

**New record of Glossogobius laticeps (Gobiiformes: Gobiidae) to Taiwan with notes on local congeneric species**

YOU-HWA CHENG — 2025-12-30

In this study, the Taiwanese Glossogobius giuris population is proven to be a new western Pacific distributional record for Glossogobius laticeps. The new addition to Taiwanese Glossogobius fauna can be characterized by having longitudinal scale rows 33–35, transverse scale rows 9–11 and predorsal scale rows 22–24. Infraorbital papillae row a branched, and rows b, cp¹ and cp² in a patch of multiple minute papilla. Trunk distinctly pigmented with numerous longitudinal black streaks in juvenile and adult, tip of chin with two small patches of melanophores and mostly unpigmented medially. A more detailed description of the genotyped materials is provided, with a discussion of the species’ distribution expansion.

First records of two brackish gobiid genera (Teleostei: Gobiidae) from Taiwan as their western Pacific distributional addenda

HSIEN-EN LI — 2025-12-30

The ichthyofauna of brackish habitats from Taiwan is relatively unexplored due to collection difficulties and significant tidal activities. Here we provide detailed descriptions of two new generic and species records for Dotsugobius bleekeri (Popta, 1921) and Mangarinus waterousi Herre, 1943. Predorsal region of both gobiids is naked entirely. Based on external morphologies, Dotsugobius bleekeri can be characterised by possessing a stout body with a somewhat teardrop-shaped lateral profile and reddish-brown body with numerous transverse creamy yellow stripes and two creamy yellow stripes under eye; Mangarinus waterousi can be characterised by having an elongate body, an oval-shaped caudal fin with a spear-shaped tip and uniformly dark brown or black body with 2 white transverse bands on anterior part of trunk and caudal peduncle. Detailed redescriptions of these two gobiids are given, with further discussions of their sympatric species and ecology patterns.

**A new species of Pseudogastromyzon Nichols (Teleostei: Balitoridae) from Fujian Province, Southeastern China**

I-SHIUNG CHEN — 2025-12-30

In this study, a new species of balitorid loach from Fujian Province was collected and described herein, namely Pseudogastromyzon putienensis. The new species can be identified by having dorsal fin iii, 7, anal fin ii, 5, pectoral fin i, 17–18, pelvic fin i, 9, lateral line scales 65–71 and vertebrae counts 38–39. For body and fin colourations, male possess greyish brown with metallic sheen, straight pale bars, and conspicuous rows of large dorsal-fin spots while females with ivory base color and distinct Y-shaped or curved bars, and transparent paired and caudal fins with striped rows. The new species was collected from the Mulan River system and is closely related to Pseudogastromyzon fasciatus; comparisons of the two species are provided herein with comments upon the taxonomy of related congeners in southeastern China.

**A new freshwater ricefish of genus Oryzias (Teleostei: Adrianichthyidae) from northern Taiwan**

I-SHIUNG CHEN — 2025-12-30

A new freshwater ricefish was collected recently from northern Taiwan, which has been identified as a species new to science. The new species, Oryzias cabaranensis sp. nov., can be well distinguished from other congeners by the following unique combination of features: (1) fin-ray counts: dorsal-fin rays 6; anal-fin rays modally 17; pectoral-fin rays 9–10; (2) body compressed laterally, body depth at pelvic origin 20.9–23.3 (22.3), body depth at anal fin origin 17.2–20.1 (18.8); (3) the dorsal-fin origin inserted almost at the vertical of 12th anal-fin rays; and (4) specific coloration: Body translucent, light creamy yellowish, a dotted, longitudinal black line. Belly wall, peritoneum slivery, somewhat subrectangular. Operculum and pre-pectoral region slivery. Eye light bluish. Caudal fin unmarked. Pelvic and anal fins with tiny melanophores. The diagnostic characters and a comparison with related species will also be provided.

**A new freshwater goby of Rhinogobius (Teleostei: Gobiidae) from the Chongkang River basin, Western Taiwan**

I-SHIUNG CHEN — 2025-12-30

A new freshwater goby of Rhinogobius was recently collected from the Chongkang River basin of Western Taiwan. The new species, Rhinogobius chongkangensis sp. nov., can be well distinguished from all other congeners by the unique combination of the following features: (1) fins: second dorsal fin rays I/9; anal fin rays I/8; pectoral fin rays modally 16; (2) squamation: longitudinal scale series 32–33 (modally 32); perdorsal scales 12–15 (modally 14); (3) vertebral count 27; (4) mouth oblique, rear edge extending to vertical between anterior margin of orbit and anterior edge of pupil in male and (5) specific colouration: lateral body with 7–8 longitudinal rows of small orange to brownish red spots about 1/6–1/10 size of pupil diameter in male; cheek and opercle with 24–32 rather small orange or brownish red spots in male, with 13–16 small brown spots in female; branchiostegal membrane with many 14–18 tiny orange or brownish red spots in male; basal region of first dorsal fin with 8–12 orange or brownish red spots in male, second dorsal fin pale with 3–4 longitudinal rows of orange spots; pectoral fin with two rows of orange to red orange spots which 4–5 larger orange spots or sometimes fusing a vertical line on upper side on anterior row in male; a snow white vertical band between the two rows of orange spots in male. A brief discussion with all nominal congeneric species is also provided.

**A new freshwater gobiid species of Rhinogobius Gill, 1859 (Teleostei: Gobiidae) from the hillstream of Julongjiang basin, Fujian Province, southeastern China**

I-SHIUNG CHEN — 2025-12-30

A new species of freshwater gobiid fish of genus Rhinogobius Gill, 1859, was collected from the Julongjiang basin, southern region of Fujian Province, China. Rhinogobius sexistriatus sp. nov. can be well distinguished from other congeners by their specific patterns of coloration and meristic features: (1) fins rays: second dorsal fin rays I/8; anal fin rays I/7; pectoral fin rays 17; (2) squamation: longitudinal scale series 26–28 (modally 27); perdorsal scales 4–5 (modally 5); (3) vertebral count 27; and (4) specific colouration: cheek with six parallel black stripes on lower side in male. Branchiostegal membrane light blue and spotless in male. First dorsal fin bright orange on more than 1/2 dorsal region in male. Second dorsal fin brownish yellow with 3 longitudinal rows of brown spots and a distal yellow margin in male. Pectoral fin base greyish with a large, wide oblique black mark and an orange spot behind in male. Caudal fin greyish with 5 vertical rows of brown spots in male. A diagnostic key to all valid species from Fujian Province, China is also provided in this paper.

**A new species of freshwater goby (Teleostei: Gobiidae: Rhinogobius) from Xijiang, Pearl River basin, Guangxi Province, China**

I-SHIUNG CHEN — 2025-12-30

A new species of freshwater gobiid fish of the genus Rhinogobius Gill, 1859, was collected from the hill stream of Xijang, Pearl River basin, Gangxi Province, China. Rhinogobius lingjiangensis can be well distinguished from all other congeners by the unique combination of the following features: (1) fin rays: second dorsal fin rays I/7–8 (usually I/8); anal fin rays I/6–7 (usually I/6); pectoral fin rays 16–17 (modally 16); (2) squamation: longitudinal scale series 31–32 (modally 31); perdorsal scales 5–6 (modally 6); (3) vertebral count 28; and (4) specific colouration: cheek with 7 rather wide reddish orange parallel bands in male; caudal fin base with a central blackish brown spot in male; pectoral fin base greyish with brown vertical bar in male, anterior basal 1/4 region of pectoral fin with semicircular creamy yellow region in male. A brief comparison of current species with related species will be addressed.