Synodontis multipunctatus Boulenger, 1898

Englmaier, Gernot K., Blažek, Radim, Zimmermann, Holger, Bartáková, Veronika, Polačik, Matej, Žák, Jakub, Mulokozi, Deogratias P., Katongo, Cyprian, Büscher, Heinz H., Mabo, Lwabanya, Koblmüller, Stephan, Palandačić, Anja & Reichard, Martin, 2024, Revised taxonomy of Synodontis catfishes (Siluriformes: Mochokidae) from the Lake Tanganyika basin reveals lower species diversity than expected, Zoological Journal of the Linnean Society 202 (3) : -

publication ID	https://doi.org/ 10.1093/zoolinnean/zlae130
persistent identifier	https://treatment.plazi.org/id/4D20DF53-FFD6-6C14-FF31-F88CCA0937F2
treatment provided by	Plazi
scientific name	Synodontis multipunctatus Boulenger, 1898
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Synodontis multipunctatus Boulenger, 1898 View in CoL

( Figs 8, 9; Supporting Information, Video S3) Synodontis multipunctatus Boulenger, 1898: 497 (type locality: Sumbu , Lake Tanganyika, Zambia).

Synodontis grandiops Wright and Page, 2006: 109 View in CoL (type locality: Mwakizega coastline, Lake Tanganyika, Tanzania).

Material examined: Type material: BMNH 1898.9 .9.76, holotype, S. multipunctatus , 222.5 mm SL, Sumbu , Lake Tanganyika, Zambia, coll. Moore. BMNH 1982.4 .13.4785, holotype, S. grandiops , 94.7 mm SL, Mwakizega coastline, Lake Tanganyika, Tanzania, coll. Travers. BMNH 1982.4 .13.4786, paratype, S. grandiops , 89.4 mm SL, Mwakizega coastline, Lake Tanganyika, Tanzania, coll. Travers. BMNH 1982.4.13.4789–4791, three, paratypes, S. grandiops , 85.7–91.7 mm SL, Kigonga Bay , Lake Tanganyika, Democratic Republic of the Congo, coll. Travers. BMNH 1920.5.25.83–84, two, paratypes, S. grandiops , 74.6– 76.1 mm SL, Vua Bay , Lake Tanganyika, Democratic Republic of the Congo, coll. Stappers. BMNH 1982.4.13.4787–4788, two, paratypes, S. grandiops , 80.4–90.5 mm SL, Elephants foot peninsula, Lake Tanganyika, Tanzania, coll. Travers. BMNH 1955.12 .20.1833, paratype, S. grandiops , 78.0 mm SL, Moba Bay , Lake Tanganyika, Democratic Republic of the Congo, coll. Explo. Hydrobiol. L. Tanganyika , 1946–1947. BMNH 1982.4 .13.4784, paratype, S. grandiops , 78.0 mm SL, Kamara Bay , Lake Tanganyika, coll. Travers. BMNH 1955.12 .20.1837, paratype, S. grandiops , 76.6 mm SL, Rumonge Bay , Lake Tanganyika, Burundi, coll. Explo. Hydrobiol. L. Tanganyika , 1946–1947. MRAC 90273–90275 View Materials , three, paratypes, S. grandiops , 95.7–110.9 mm SL, Au large de la Malagarazi, stat. 63, à 10–15 km de la côte, Lake Tanganyika, Tanzania, coll. Poll , 1947. MRAC 91606–91607 View Materials , two, paratypes, S. grandiops , 96.9– 97.5 mm SL, Uvira , Lake Tanganyika, Democratic Republic of the Congo, coll. Marlier , 1949. MRAC 53096–53097 View Materials , two, paratypes, S. grandiops , 79.6–89.2 mm SL, Nyanza , Lake Tanganyika, Burundi, coll. Testiade , 1937. MRAC 39186– 39188 View Materials , three, paratypes, S. grandiops , 72.7–79.8 mm SL, Moba , Lake Tanganyika, Democratic Republic of the Congo, coll. Van Maldern , 1932.

Non-type material: BMNH 1906.9.8.70–71, two, 180.4– 200.4 mm SL, Niamkolo , Lake Tanganyika, Zambia, coll. Cunningham. BMNH 1955.12.20.1840–1841, two, 172.5– 200.0 mm SL, Par le traves de la Ruzizi direction Usumbura, Lake Tanganyika, Burundi, coll. Explo. Hydrobiol. L. Tanganyika , 1946–1947. BMNH 1955.12.20.1843–1844, three, 133.5–139.4 mm SL, Entevers du pond de la Baie de Burton, Lake Tanganyika, Democratic Republic of the Congo, coll. Explo. Hydrobiol. L. Tanganyika , 1946–1947. BMNH 1955.12 .20.1845, one, 169.2 mm SL, M’Pala , rec. Mission de M’Pala, Lake Tanganyika , Democratic Republic of the Congo, coll. Explo. Hydrobiol. L. Tanganyika, 1946–1947. BMNH 1955.12.20.1855–1856, one, 119.2 mm SL, Au large de la pointe sud du delta de la Malagarasi, Lake Tanganyika, Tanzania, coll. Explo. Hydrobiol. L. Tanganyika , 1946–1947. BMNH 1936.6.15.1206–1226,15,76.2–214.9 mmSL, KibangaBay , Lake Tanganyika, Democratic Republic of the Congo, coll. Christy. ISRNB 9263 , one, 191.6 mm SL, Devant la Lugumb (l)a, dist Tanganika Congo Belg, Lake Tanganyika, Democratic Republic of the Congo . ISRNB 9262 , one, 187.6 mm SL, Au large de Kazele (centre Ubwari), Lake Tanganyika, Democratic Republic of the Congo . MRAC 39189–39192 View Materials , two, 72.3–189.8 mm SL, Moba , Lake Tanganyika, Democratic Republic of the Congo, coll. Van Malderen , 1932. MRAC 90281 View Materials , one, 189.5 mm SL, Au large de la pointe Sud du delta de la Malagarazi, stat. 147, Lake Tanganyika, Tanzania, coll. Poll , 1947. MRAC 90276– 90277 View Materials , two, 149.9–166.3 mm SL, Au large de la Malagarazi, stat. 63, à 10–15 km de la côte, Lake Tanganyika, Tanzania, coll. Poll , 1947. MRAC 90265 View Materials , one, 163.6 mm SL, Albertville , Lake Tanganyika, Democratic Republic of the Congo, coll. Poll , 1946. MRAC 45737–45739 View Materials , three, 157.0– 167.2 mm SL, Rumonge , Lake Tanganyika, Burundi, coll. Lestrade , 1935. MRAC 90285–90286 View Materials , two, 168.3–172.6 mm SL, Lagosa , Lake Tanganyika, Tanzania, coll. Poll , 1947. NMW 100743 View Materials , three, 69.7–71.7 mm SL, Katete (8°19 ʹ 42.2″S, 30°31 ʹ 38.3″E), Lake Tanganyika , Zambia, coll. Reichard, Zimmermann, Bartáková, Polačik GoogleMaps , 2021. NMW 100744 View Materials , five, 60.0– 73.7 mm SL, Mpende Fisheries (8°28 ʹ 56.9″S, 30°28 ʹ 00.1″E), Lake Tanganyika , Zambia, coll. Reichard, Zimmermann, Bartáková, Polačik GoogleMaps , 2021. NMW 100745 View Materials , six, 60.0– 78.4 mm SL, Mbita Island (8°45 ʹ 14.8″S, 31°05 ʹ 04.7″E), Lake Tanganyika, Zambia, coll. Reichard, Blažek, Zimmermann, Bartáková, Polačik GoogleMaps , 2021. NMW 100746 View Materials , five, 53.3–62.6 mm SL, Kalambo (8°37 ʹ 24.9″S, 31°11 ʹ 59.5″E), Lake Tanganyika , Zambia, coll. Reichard, Blažek, Zimmermann, Bartáková, Polačik GoogleMaps , 2021. NMW 100747 View Materials , five, 58.8–61.3 mm SL, Katukula (8°43 ʹ 20.3″S, 30°56 ʹ 35.1″E), Lake Tanganyika , Zambia, coll. Blažek, Zimmermann, Bartáková, Polačik, Koch GoogleMaps , 2022. NMW 100748 View Materials , three, 70.5–76.5 mm SL, Mbita Island (8°45 ʹ 14.8″S, 31°05 ʹ 04.7″E), Lake Tanganyika, Zambia, coll. Blažek, Zimmermann, Bartáková, Polačik, Koch GoogleMaps , 2022. NMW 100749 View Materials , five, 57.6–62.3 mm SL, Crocodile Island (8°42 ʹ 28.45″S, 31°7 ʹ 17.82″E), Lake Tanganyika, Zambia, coll. Blažek, Zimmermann, Bartáková, Polačik, Koch GoogleMaps , 2022. NMW 100750 View Materials , two, 68.8–70.2 mm SL, Nondwa Point (4°51 ʹ 50.1″S, 29°36 ʹ 28.6″E), Kigoma, Lake Tanganyika , Tanzania, coll. Reichard, Zimmermann GoogleMaps , 2022. NMW 100751 View Materials , two, 45.6– 58.7 mm SL (and one C&S specimen in a separate jar, 68.7 mm SL, NMW 100782 View Materials ), Hilltop cave site (4°53 ʹ 11.01″S, 29°36 ʹ 47.22″E), Kigoma, Lake Tanganyika, Tanzania, coll. Reichard, Zimmermann GoogleMaps , 2022. NMW 100752 View Materials , three, 75.1– 90.0 mm SL, Nondwa Point (4°51 ʹ 50.1″S, 29°36 ʹ 28.6″E), Kigoma, Lake Tanganyika , Tanzania, coll. Reichard, Blažek, Zimmermann GoogleMaps , Englmaier, 2023. NMW 100753 View Materials , two, 75.8– 91.2 mm SL, Jacobson’s Beach (4°55 ʹ 3.00″S, 29°35 ʹ 44.01″E), Kigoma, Lake Tanganyika , Tanzania, coll. Reichard, Blažek, Zimmermann GoogleMaps , Englmaier, 2023. NMW 100754 View Materials , one, 82.1 mm SL, Cape Kabogo, site 1 (5°27 ʹ 42.45″S, 29°44 ʹ 50.19″E), Lake Tanganyika , Tanzania, coll. Reichard, Blažek, Zimmermann GoogleMaps , Englmaier, 2023. NMW 100755 View Materials , one, 94.0 mm SL, Cape Kabogo, site 2 (5°28 ʹ 38.62″S, 29°45 ʹ 35.82″E), Lake Tanganyika , Tanzania, coll. Reichard, Blažek, Zimmermann GoogleMaps , Englmaier, 2023. NMW 100756 View Materials , three, 81.4–116.3 mm SL, Cape Kabogo, site 3 (5°30 ʹ 9.56″S, 29°47 ʹ 14.94″E), Lake Tanganyika , Tanzania, coll. Reichard, Blažek, Zimmermann GoogleMaps , Englmaier, 2023. NMW 100757 View Materials , five, 61.0– 85.4 mm SL, Kalilani (6°0 ʹ 56.77″S, 29°44 ʹ 46.86″E), Lake Tanganyika , Tanzania, coll. Reichard, Blažek, Zimmermann GoogleMaps , Englmaier, 2023. NMW 100758 View Materials , five, 70.6–83.4 mm SL, Mabilibili (6°27 ʹ 26.51″S, 29°55 ʹ 2.41″E), Lake Tanganyika , Tanzania, coll. Reichard, Blažek, Zimmermann GoogleMaps , Englmaier, 2023. NMW 100759 View Materials , five, 85.5–100.3 mm SL, Sibwesa ( Edith Bay ) (6°28 ʹ 54.09″S, 29°55 ʹ 43.61″E), Lake Tanganyika, Tanzania, coll. Reichard, Blažek, Zimmermann GoogleMaps , Englmaier, 2023. NMW 100760 View Materials , five, 67.0– 80.2 mm SL, Karema (6°54 ʹ 57.18″S, 30°30 ʹ 1.66″E), Lake Tanganyika , Tanzania, coll. Reichard, Blažek, Zimmermann GoogleMaps , Englmaier, 2023. NMW 100761 View Materials , eight, 65.4–77.8 mm SL, Rutunga, Burundi (3°38 ʹ 47.03″S, 29°20 ʹ 8.02″E), coll. Jiten Vaitha, Whiteboard Enterprises Ltd GoogleMaps , 2022. ZMB 19792 View Materials , one, 90.6 mm SL, N. Tanganyika, D.O.A., Lake Tanganyika , Tanzania, coll. Wintgens.

Diagnosis: Synodontis multipunctatus is distinguished from congeners in LT by a unique combination of characters: presence of a large axillary pore; no granular papillae on head, body, and fins; dorsal spine pigmented and dark, only its tip and the upper flexible part unpigmented and white; anal fin commonly unpigmented, only having a small dark spot at base; 13–29 (median 20) mandibular teeth, commonly arranged in four symmetric rows of replacement teeth; 20–58 (median 31) primary premaxillary teeth; 0–5 (median 0) secondary branches on inner mandibular barbels; and 38–40 (median 39) total vertebrae, with 18–22 (median 20) caudal vertebrae.

Description: The general appearance of S. multipunctatus is shown in Figures 8 and 9 and Supporting Information, Video S3; axial skeletons in Supporting Information, Figure S8E, F; and relative measurements, meristic counts, and coded characters are given in Supporting Information, Table S12.

Longest examined specimen 222.5 mm SL (female, BMNH 1898.9.9.76, holotype, S. multipunctatus ). Males and females of similar size (males 56.4–200.0 mm SL, mean 107.6 mm, N = 55; females 53.3–222.5 mm SL, mean 91.0 mm, N = 69). Body moderately compressed laterally. In smaller specimens, dorsal head profile and predorsal back usually convex to dorsal-fin origin; in larger specimens, straight and slightly convex at nape. Predorsal back rising in an angle of 20°–23° (against midline of body). Postdorsal profile falling straight to adipose-fin origin and usually straight or slightly convex to caudal-fin origin. Body depth at anal-fin insertion greater than half of body depth at dorsal-fin origin. Head dorsoventrally compressed; depth at posterior eye margin greater than maximal cranium width. Snout blunt and shorter than half of head length. Mouth subterminal, with abundant papillae on lips; width 55.5%–98.8% of snout length. Eye diameter usually greater than half of snout length, not significantly correlated with SL ( R = −0.02, Spearman’s rank correlation, N = 136).

Head, body, and fins usually without or with only few non-granular papillae. Occipitonuchal shield and humeral process rugose and of granular texture. Humeral process usually narrow and elongated; maximal depth 19.2%–38.5% (N = 10) of its length. Large, conspicuous axillary pore at anterior ventral margin of humeral process, usually with a series of openings. Orange or yellow secretion from pore in freshly preserved specimens.

Adipose fin well demarcated; basal length 21.3%–41.7% of SL, extending over 41.5%–81.5% of distance between dorsal-fin insertion and end of caudal peduncle. Adipose-fin insertion distant to end of caudal peduncle. Dorsal fin with two unbranched rays and commonly seven branched rays; dorsal spine densely serrated on lower anterior edge, poorly marked serrations on upper anterior edge, posterior edge with 7–17 serrae; length of dorsal spine, excluding upper flexible part, 58.3%–104.7% of head length and slightly shorter than length of pectoral spine (excluding upper flexible part). Anal fin with commonly four unbranched and seven branched rays; longest rays usually reaching beyond level of posterior edge of adipose fin. Pelvic fin with a single unbranched ray and six branched rays. Pectoral fin with a single unbranched ray and commonly eight branched rays; pectoral spine densely serrated on anterior (10–26 serrae) and posterior (16–35 serrae) edges. Pectoral fin usually slightly shorter than pectoral–pelvic distance, but in some specimens reaching above pelvic-fin origin in folded position. Caudal fin forked with 2 + 15 principal rays; number of upper procurrent rays (9–12, median 10, N = 25) less than number of lower procurrent rays (11–14, median 12, N = 24).

Mandibular teeth 13–29 (median 20, N = 134) (holotype of S. multipunctatus 18, holotype of S. grandiops 21), unicuspid, arranged in four or six symmetric rows of replacement teeth. Primary premaxillary teeth 20–58 (median 31, N = 135) (holotype of S. multipunctatus 57, holotype of S. grandiops 40), arranged in two or three irregular rows. Number of primary premaxillary teeth positively correlated with SL ( R = 0.58, Spearman’s rank correlation, N = 135). Secondary and tertiary premaxillary teeth small, arranged in two or three rows and two rows, respectively.

Maxillary barbels long, usually reaching beyond pectoral-fin insertion (shorter in 28 of 136 specimens). Outer mandibular barbels 39.0%–77.7% of head length, with 3–7 (median 5, N = 135) primary branches; secondary branches absent (present in only six specimens). Inner mandibular barbels with 4–10 (median 7, N = 135) primary branches and 0–5 (median 0, N = 135) secondary branches; secondary branches present in 60% of specimens examined.

Lateral-line canals ossified, not extending beyond posterior margin of last complex centrum. One specimen (NMW 100782) with 57 ossified canals. Frontal fontanel (examined in one specimen, 68.7 mm SL, NMW 100782) originating posterior to centre between eyes and extending beyond posterior margin of mesethmoid; length greater than interorbital distance between frontal margins; posterior margin extending behind the bony bridge, resembling state C in the paper by Pinton (2008: fig. 15).

Total vertebrae 38–40 (median 39, N = 69) (holotype of S. multipunctatus 40, holotype of S. grandiops 39), abdominal vertebrae 17–20 (median 19), preanal caudal vertebrae 1–3 (median 2), and postanal caudal vertebrae 17–20 (median 18).

Length of digestive tract (not stretched) ~58%–149% (mean 115%) of SL (N = 21, 51.6–104.0 mm SL).

Coloration: In life (Supporting Information, Video S3), body coloration light brown, cream, or slightly yellowish; ventral side whitish. Body covered with abundant black spots of variable size/shape (smallest on head); spots few or absent on ventral side; spots generally larger in smaller specimens. Dorsal and pectoral fins pigmented and usually black (sometimes only indistinct spots present), posterior margins unpigmented and white. Dorsal spine dark, and only its tip and the upper flexible part unpigmented. Anal and pelvic fins commonly unpigmented and white, usually having a small dark spot at base. Lobes of caudal fin with black bars (sometimes only spots present), outer margins unpigmented. Maxillary and mandibular barbels unpigmented and white. Iris copper coloured.

In formalin (initial fixation) and later transferred to 75% ethanol ( Figs 8A, 9A), coloration similar to that in live specimens, commonly slightly darker. Orange or yellowish around axillary pore region. In 75% of specimens (N = 136), spots absent on ventral side. First branched dorsal-fin ray: 43%–72% (mean 56%, N = 29) pigmented and dark (from base) vs. 28%–57% (mean 44%) unpigmented and cream coloured (from tip).

After long-term preservation in 75% ethanol ( Figs 8B, C, 9B, C), historical specimens light brown, cream coloured on ventral side; abundant brown spots visible on head, dorsal and lateral side of body, and on dorsal, adipose, and caudal fins.

Distribution and habitat: Endemic to LT ( Fig. 1). Synodontis multipunctatus inhabits the entire range from 2 m down to our maximal diving depth at 40 m. Coulter (1991) reported the species from a maximal depth of 170 m. During the day, S. multipunctatus is more common below 10 m, but during the night it can be observed in very shallow depths up to 0.5 m. Synodontis multipunctatus seems to be least bound to rocky habitats among the commonly found LT Synodontis species and may even dwell between scattered rocks on sandy bottoms, where it can be seen transitioning between several rocks even under daylight. It seems that smaller but already adult individuals inhabit shallower areas, whereas bigger ones can be found in deeper regions. No obvious differences in habitat use were observed between the southern and northern lake basins. Synodontis multipunctatus either occurs solitary or in groups of 2–6 individuals. On rare occasions, groups of up to several hundred individuals were observed (Kigoma, Tanzania: A. Indermaur, pers. comm.).