Belobranchus segura Keith, Hadiaty & Lord, 2012

Afrisal, Muhammad, Nurjirana, Nurjirana, Haryono, Haryono, Mokodongan, Daniel Frikli, Wibowo, Kunto, Moore, Abigail Mary & Hubert, Nicolas, 2025, Revised diagnoses of the gudgeons Belobranchus belobranchus and B. segura (Actinopterygii, Gobiiformes, Eleotridae), ZooKeys 1232, pp. 173-186 : 173-186

Belobranchus segura Keith, Hadiaty & Lord, 2012

Figs 1 , 2 , 3 E – H , 4 , 5 B , 6 , Tables 1 , 2 New English name: Segura Gudgeon

Belobranchus segura Keith, Hadiaty & Lord, 2012: 480, figs 1, 2, 3 A, 3 C (type locality: Ake Jira, Leililef Waibulen, Halmahera, Indonesia)

Material examined.

Holotype. MZB.20786 , 72.1 mm SL, male, Ake Jira , Leililef Waibulen, Halmahera, Indonesia, R. Hadiaty et al., 26 Jan. 2010.

Paratypes. 9 specimens, 40–72 mm SL, all specimens collected from Maluku Island, Indonesia . • MZB.18658 , 61–66 mm SL, 2 males, Ake Kobe , Halmahera, R. Hadiaty et al., 23 Jan. 2010 • MZB.18684 , 64–72 mm SL, 3 males, same data as holotype • MZB.18747 , 55 mm SL, female, MZB.18751 , 40–44 mm SL, 2 females, MZB.18820 , 44 mm SL, female, Ake Jira , Weda Tengah, Halmahera, R. Hadiaty et al., 4–7 Feb. 2010 .

Non-type materials.

78 specimens, 33.4–79.8 mm SL, all specimens collected from Indonesia. Java: • MZB.23934 , 33.9 mm SL, male, Purworejo , Jawa Tengah, R. Hadiaty, 10 Sep. 2017 • MZB.26667 (ex BIF.1483 ), 42.1 mm SL, male, MZB.26890 [ex BIF.1482 ], 39.1 mm SL, male, Cibeber , Pandeglang, Banten, 6°35'29.0"S, 105°37'48.0"E, N. Hubert et al., 7 Dec. 2013 . Bali: • MZB.26668 (ex BIF.2389 ), 56.3 mm SL, female, MZB.26891 (ex BIF.2386 ), 50.2 mm SL, female, MZB.26892 (ex BIF.2374 ), 55.1 mm SL, male, MZB.26893 (ex BIF.2375 ), 61.5 mm SL, male, MZB.26894 (ex BIF.2387 ), 52.6 mm SL, female, MZB.26895 (ex BIF.2373 ), 59.0 mm SL, male, MZB.26896 (ex BIF.2376 ), 60.8 mm SL, male, MZB.26897 (ex BIF.2388 ), 35.9 mm SL, female, Nbang , Jembrana, Bali, 8°22'01.2"S, 114°45'07.2"E, N. Hubert et al., 15 Apr. 2014 • MZB.26670 (ex BIF.2460 ), 52.0 mm SL, female, MZB.26898 (ex BIF.2457 ), 60.3 mm SL, male, MZB.26899 (ex BIF.2456 ), 65.1 mm SL, male, MZB.26900 (ex BIF.2459 ), 55.3 mm SL, male, MZB.26901 (ex BIF.2454 ), 69.2 mm SL, male, MZB.26902 (ex BIF.2455 ), 68.9 mm SL, male, Yeh Sumbul , Jembrana, Bali, 8°21'36.0"S, 114°47'02.4"E, N. Hubert et al., 16 Apr. 2014 . Sulawesi: • MZB.11715 , 41.3–52.1 mm SL, 6 specimens, 2 males, 4 females, MZB.11717 , 46.1–68.0 mm SL, 6 specimens, 3 males, 3 females, MZB.11727 , 37.8–62.2 mm SL, 6 specimens, 4 males, 2 females, Baliohuto , Lombongo, Suwawa, Gorontalo, Haryono and A. Munim, 6–8 Aug. 2001 • MZB.12048 , 62.3 mm SL, female, Molong , Pusian Dumoga, Bolaang Mongondow, Sulawesi Utara, Haryono and Hesron, 26 May 2002 • MZB.26663 (ex MZB.11676 ), 47.3–69.4 mm SL, 11 specimens, 6 males, 5 females, Mountong , Donggala, Sulawesi Tengah, Agus, 2 May 2002 • MZB.26664 (ex MZB.1197 ), 61.2–76.1 mm SL, male and female, Bolaang Mongondow , Sulawesi Utara, Haryono and Hesron, 22 May 2002 • MZB.26669 (ex MZB.22703 ), 49.1–50, 4 mm SL, male and female, Bonepuso , Bulagi Selatan, Banggai Kepulauan, S. Sauri, 20 Sep 2014 . Lombok: • MZB.22933 , 42.0– 50.5 mm SL, 3 females, Ormori , Kawinda Toi , Tambora, Sumbawa, Nusa Tenggara Barat, Mulyadi, 24 Apr. 2015 . Flores: • MZB.6359 , 43.4–53.5 mm SL, 4 specimens, 2 males, 2 females, Wae Laku , Ruteng, Flores, Nusa Tenggara Timur, Agus and Munir, 26 May 1994 . Timor: • MZB.26903 , 59.6 mm SL, male, MZB.26904 , 59.6 mm SL, male, MZB.26905 , 57.8 mm SL, male, MZB.26906 , 44.4 mm SL, male, MZB.26908 , 66.1 mm SL, male, Jenilu , Kakuluk Mesak, Belu, Nusa Tenggara Timur, 9°00'41.8"S, 124°52'52.2"E, M. Afrisal et al., 23 Jan. 2023 . Halmahera: • MZB.18700 , 67.2 mm SL, male, MZB.18706 , 76.4–79.8 mm SL, 3 males, MZB.18711 , 56.7 mm SL, female, MZB.26909 (ex MZB.18820 ), 59.0– 58.1 mm SL, 2 females, Ake Jira , Weda Tengah, R. Hadiaty et al., 27 Jan. – 7 Feb. 2010 • MZB.21219 , 58.2 mm SL, female, Ake Kobe , Weda Tengah, R. Hadiaty et al., 7 Jul. 2011 • MZB.26665 (ex MZB.18747 ), 38.4–43.8 mm SL, 2 females, MZB.26666 (ex MZB.18751 ), 33.4–43.0 mm SL, 4 females, Ake Saki , Weda Tengah, R. Hadiaty et al., 7 Feb. 2010 .

Diagnosis.

A species of Belobranchus with the following combination of characters: head somewhat convex; interorbital width 6.4–11.6 % (mean 8.2 %) of SL; jaw length 8.7–13.5 % (11.1 %) of SL; caudal-peduncle depth 13.2–16.6 % (14.7 %) of SL; body with 4 or 5 dark-brown bands separated by narrow pale bars, lacking dark horizontal lines; dorsal and lateral surfaces of head without small whitish spots; 3 or 4 oblique brown lines extending from eye to posterior edge of operculum; upper margin of first dorsal fin yellowish to orange; largest recorded specimen 79.8 mm SL.

Distribution and habitat.

Belobranchus segura has been recorded from Indonesia: Sumatra, Java, Bali, Lombok, Sulawesi, Halmahera, Sumbawa, Flores, Timor, Papua Barat ( Kottelat et al. 1993; Keith et al. 2012; Dahruddin et al. 2016; Miesen et al. 2016; Sahami and Habibie 2021; Hasan et al. 2023; this study), the Philippines ( Vedra et al. 2013), Japan ( Suzuki et al. 1995), Papua New Guinea ( Amick and Toko 2021: fig. 2 P, Q), Solomon Islands and Vanuatu ( Keith et al. 2012), and Philippines ( Gonzalez et al. 2023) (Fig. 6 ). This species is considered amphidromous ( Keith et al. 2012; Sahami and Habibie 2021) and has been found in the lower reaches of muddy to clear rivers with sandy to gravel substrate, to 5 m in altitude, close to estuaries. Like most eleotrids, this fish is considered carnivorous ( Kiruba-Sankar et al. 2018).

Figures

Figure 1. Neighbor-join phylogenetic tree of COI GenBank accessions for the genus Belobranchus [Kimura 2 - Parameter model (K 2 P); 1000 bootstrap replications; Eleotris fusca as outgroup].

Figure 2. Morphometric relationships in Belobranchus belobranchus (circles) and B. segura (triangles) A interorbital width B jaw length C caudal-peduncle depth.

Figure 3. Fresh specimens of Belobranchus species A – D B. belobranchus A MZB. 26873, 77.5 mm SL B MZB. 26907, 74.8 mm SL C MZB. 26872, 71.7 mm SL D MZB. 26906, 58.7 mm SL) E – H B. segura E MZB. 26902, 68.9 mm SL F MZB. 26687, 59.6 mm SL G MZB. 26668, 56.3 mm SL H MZB. 26894, 52.6 mm SL.

Figure 4. Preserved specimens of B. segura A MZB. 20786, holotype, 72.1 mm SL B MZB. 18747, paratype, 55.9 mm SL C, D caudal fins of the holotype and the paratype, respectively.

Figure 5. Schematic illustration of the number and patterns of lines on the cheek and lateral bands on the body of Belobranchus species A B. belobranchus B B. segura.

Figure 6. Distributional records of B. belobranchus (circles) and B. segura (triangles) based on collected specimens examined in this study.