Devario malabaricus ( Jerdon, 1849 )

Sudasinghe, Hiranya, Pethiyagoda, Rohan & Meegaskumbura, Madhava, 2025, Species without borders: the diversification of giant danios in Sri Lanka (Teleostei, Danionidae, Devario), Evolutionary Systematics 9 (2), pp. 229-258 : 229-258

Devario malabaricus ( Jerdon, 1849)

Perilampus malabaricus Jerdon, 1849 .

Devario monticola Batuwita, de Silva & Udugampala, 2017 .

Danio lineolatus Bleeker, 1863 a .

Material examined.

109 ex., see Suppl. material 1.

Diagnosis.

Devario malabaricus is distinguished from Sri Lankan congeners by the combination of the following characters and character states: anal-fin origin posterior to dorsal-fin origin, beneath 3 rd branched dorsal-fin ray (vs anal-fin origin on vertical through dorsal-fin origin in D. memorialis ); 1 st infraorbital smooth, with no infraorbital process (vs present in D. micronema , D. pathirana , and most specimens of D. altus ); P-stripe usually bifurcated anteriorly (vs P-stripe not bifurcated in D. altus and D. memorialis ); interstripe I + 1 short, usually not extending uninterrupted anterior to vertical through pelvic-fin origin (vs long, extending uninterrupted anterior to vertical through pelvic-fin origin in D. altus ); caudal peduncle length 12.3–19.4 % SL (vs 19.2–21.4 % SL in D. altus ); caudal peduncle depth 9.8–12.9 % SL (vs 8.1–9.8 % SL in D. memorialis ); body depth 26.1–35.4 % SL (vs 21.8–26.0 % SL in D. altus ; 15.9–22.6 % SL in D. memorialis ); dorsal-fin base length 16.7–23.5 % SL (vs 13.5–16.3 % SL in D. memorialis ); pelvic-fin height 13.3–18.1 % SL (vs 11.6–13.3 % SL in D. memorialis ); 33–39 pored lateral-line scales (vs 38–46 in D. memorialis ); predorsal scales 14–18 (vs 17–19 in D. memorialis ); 12–15 circumpeduncular scales (vs 15–18 in D. memorialis ); 7 ½ - 9 scales between lateral line and dorsal-fin origin (vs 7 ½ in D. memorialis ; 6–7 ½ in D. altus ); 9 ½ - 12 ½ branched dorsal-fin rays (vs 8 ½ in D. memorialis ).

Devario malabaricus is genetically distinct from D. altus , its closest congener, by 1.2–1.7 % in the cox 1 DNA barcoding marker, and from the remaining Sri Lankan species of Devario by more than 2.8 %. Sexual dimorphism is apparent in D. malabaricus , with the branched rays of the pectoral fin exhibiting tubercles in males but not in females ( Sudasinghe 2024).

Habitat and distribution.

Devario malabaricus is the only non-endemic member of the genus in Sri Lanka: it occurs also in peninsular India. It is the most widespread species of Devario on the island, a generalist that utilizes lotic and lentic, shaded and unshaded, clear and turbid, and disturbed and undisturbed habitats, from lowland floodplains to hill streams and torrents.

Remarks.

Kullander et al. (2017) and Sudasinghe and Pethiyagoda (2019) showed that the neotype designation for Perilampus malabaricus Jerdon, 1849 by Batuwita et al. (2017) is inconsistent with Article 75.3. 1 of the International Code of Zoological Nomenclature and hence, invalid. Although Devario malabaricus lacks a name-bearing type, it is common in its type locality, Malabar, which is unambiguously defined in contemporaneous maps. While Indian samples of D. malabaricus were not included in the present analysis, previous work ( Batuwita et al. 2017; Sudasinghe et al. 2020 a) has shown through both morphological and genetic analysis, that the Indian and Sri Lankan populations are conspecific.