Short Communication |
Corresponding author: Gernot K. Englmaier ( gernotenglmaier@gmx.at ) Academic editor: Pedro Bragança
© 2023 Gernot K. Englmaier, Rupert A. Collins.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Englmaier GK, Collins RA (2023) Invalid lectotypification for Synodontis victoriae Boulenger, 1906 (Siluriformes, Mochokidae) by Poll (1971), and the designation of a new lectotype. ZooKeys 1183: 65-72. https://doi.org/10.3897/zookeys.1183.111868
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The lectotype and paralectotype of Synodontis victoriae Boulenger, 1906, designated by
Catfish, East Africa, freshwater fish, ICZN, taxonomy
Based on an extensive collection of fishes from Lake Victoria made by Edward J.E. Degen in 1905,
First illustration of Synodontis victoriae published in "The Fishes of the Nile" (modified from
After careful examination of the two type specimens, we found inconsistencies in both the information presented by
The types of Synodontis victoriae were examined, and 36 morphometric measurements and 20 meristic characters, including four axial skeleton counts (from radiographs), were taken. Measurements were made point-to-point using callipers to the nearest 0.1 mm. Most measurements (21) follow
The two types of Synodontis victoriae differ considerably in state of preservation and can therefore be easily distinguished (Figs
Inconsistencies regarding the lectotype designation by
This situation does not allow to unequivocally identify a unique name-bearing type in S. victoriae, presenting a nomenclatural problem when lectotype designation cannot be unambiguously traced back to a single specimen. Article 74.5 of the
From the discussion above, we conclude that the lectotypification for S. victoriae by
Lectotype (hereby designated): BMNH 1906.5.30.191, Entebbe, 188.2 mm SL, coll. E. Degen.
Paralectotype : BMNH 1906.5.30.190, Buganga, 225.0 mm SL, coll. E. Degen.
In Figs
Morphometric measurements and meristic counts for type specimens of Synodontis victoriae. Vertebral counts indicate numbers of total vertebrae: abdominal vertebrae + caudal vertebrae / postanal vertebrae.
Character states | S. victoriae BMNH 1906.5.30.191 lectotype | S. victoriae BMNH 1906.5.30.190 paralectotype |
---|---|---|
Standard length (mm) | 188.2 | 225.0 |
MORPHOMETRIC DATA | ||
Percent of standard length | ||
Body depth at dorsal fin origin | 23.1 | 25.8 |
Body depth at anal fin origin | 24.1 | 26.1 |
Body depth at anal fin insertion | 19.0 | 19.4 |
Predorsal length | 37.3 | 37.4 |
Prepectoral length | 26.0 | 25.3 |
Prepelvic length | 54.0 | 54.4 |
Preanal length | 72.8 | 77.0 |
Pectoral–pelvic distance | 32.0 | 32.5 |
Pelvic–anal distance | 20.8 | 22.9 |
Caudal-peduncle length | 14.7 | 13.8 |
Dorsal fin to caudal peduncle | 52.4 | 48.7 |
Adipose basal length | 27.7 | 31.6 |
Dorsal-fin depth | 25.5 | 23.9 |
Anal-fin depth | 19.9 | 18.6 |
Pectoral-fin length | 24.2 | 24.2 |
Pelvic-fin length | 14.8 | 15.8 |
Head length | 27.1 | 27.6 |
Percent of head length | ||
Head depth at posterior eye margin | 57.3 | 59.0 |
Head width at posterior eye margin | 70.6 | 68.8 |
Maximum cranium width | 53.7 | 56.6 |
Snout length | 43.3 | 48.4 |
Interorbital width | 42.0 | 43.6 |
Maxillary-barbel length | 97.6 | 100.3 |
Outer mandibular-barbel length | 50.4 | 49.8 |
Inner mandibular-barbel length | 32.7 | 28.8 |
Humeral-process length | 53.1 | 52.6 |
Pectoral spine length (unsegmented) | 82.2 | absent |
Dorsal spine length (unsegmented) | 81.2 | absent |
Percent of snout length | ||
Orbit diameter | 45.2 | 37.9 |
Mouth width | 64.3 | 64.8 |
Premaxillae width | 44.3 | 32.6 |
Width of mandibular teeth row | 20.8 | 19.9 |
Percent of caudal peduncle length | ||
Minimum caudal-peduncle depth | 71.7 | 68.2 |
Adipose to caudal peduncle | 68.5 | 68.8 |
Percent of Dorsal fin to caudal peduncle | ||
Dorsal-adipose length | 29.3 | 17.3 |
MERISTIC DATA | ||
Dorsal fin rays | II-7 | II-8 |
Anal fin rays | V-9 | V-9 |
Pelvic fin rays | I-6 | I-6 |
Pectoral fin rays | I-9 | I-9 |
Caudal-fin principal rays (upper lobe + lower lobe) | 7+8 | 8+8 |
Caudal-fin procurrent rays (upper + lower) | 12+14 | 13+13 |
Mandibular teeth + Primary premaxillary teeth | 18+27 | 20+26 |
Branches on outer mandibular barbels | 4 | 5 |
Branches on inner mandibular barbels | 5 | 8 |
Vertebral counts | 39:18+21/19 | 40:17+23/19 |
We thank Oliver Crimmen (BMNH), Nina Bogutskaya (NHMW), and several colleagues for nomenclatural discussions. We thank Lucie Goodayle for photography and Emily Phelps for assisting with radiography.
The authors have declared that no competing interests exist.
No ethical statement was reported.
This work was supported by the Czech Science Foundation (grant number 21-00788X).
Conceived and coordinated the study: GKE. Morphological examination: GKE, RAC. Coordinated photographs and specimen preparation: RAC. Wrote the first draft of the paper: GKE. Both authors contributed equally to the improvement of the manuscript.
Gernot K. Englmaier https://orcid.org/0000-0002-9746-4500
Rupert A. Collins https://orcid.org/0000-0002-9135-1169
All of the data that support the findings of this study are available in the main text.