Engraulicypris gariepinus
Notice: | This page is derived from the original publication listed below, whose author(s) should always be credited. Further contributors may edit and improve the content of this page and, consequently, need to be credited as well (see page history). Any assessment of factual correctness requires a careful review of the original article as well as of subsequent contributions.
If you are uncertain whether your planned contribution is correct or not, we suggest that you use the associated discussion page instead of editing the page directly. This page should be cited as follows (rationale):
Citation formats to copy and paste
BibTeX: @article{Riddin2016ZooKeys, RIS/ Endnote: TY - JOUR Wikipedia/ Citizendium: <ref name="Riddin2016ZooKeys">{{Citation See also the citation download page at the journal. |
Ordo: Cypriniformes
Familia: Cyprinidae
Genus: Engraulicypris
Name
Engraulicypris gariepinus Barnard, 1943 stat. rev. – Wikispecies link – Pensoft Profile
- Engraulicypris gariepinus Barnard, 1943. Annals of the South African Museum 36(2): 220. Syntypes: 2 unsexed (not located), “Orange River and Fish River” [SAM 18722–23] [lost].
Material examined
SAIAB 193617, 6 unsexed, 2 cleared & stained: SL 43–44 mm. Namibia, Orange River, Noordower, 28°44'50"S 17°36'32"E, 21 October 2006, R. Bills; SAIAB 78822, 7 unsexed, 2 cleared & stained: SL 39–41 mm. Namibia, Orange River, Felix Unite Camp, 28°41'19"S 17°33'20"E, 20 October 2006, R. Bills; 2 unsexed, SAIAB 78805, 42–47 mm. Namibia, Orange River, Houms River Camp Site, 28°52'5"S 18°36'42"E, 18 October 2006, R. Bills; SAIAB 74232, 10 unsexed, 2 cleared & stained: SL 29–41 mm. South Africa, Orange River, Pella Drift lower site, 28°57'47"S 19°6'36"E, 28 January 2004, R. Bills & N. Jones.
Diagnosis
Caudal fin membrane clear to pale orange towards midline; anal fin extending over three quarters of length of caudal peduncle; caudal peduncle short; operculum entirely (not partially) shiny; body midline silver (not black); iris dark to light grey (not white); head with tubercles along lower jaw and lower head in breeding males; snout rounded, with dense dark spotting on tip; pelvic fin melanophores absent.
Morphology
(Figs 6–8; Table 6). Maximum SL 46 mm. Body elongated; somewhat fusiform; laterally compressed. Maximum body depth before pelvic fin. Pre-dorsal profile straight or slightly convex behind head. Head length 21% SL; with tubercles along lower jaw and lower head. Snout rounded; short; 32% of head length. Mouth terminal; slightly crescent-shaped with long anterior side; reaching anterior border of orbit. Nostrils large; level with dorsal margin of eye; separated from orbit by less than one orbit radius. Tubular anterior naris short; adjacent to open posterior naris. Eye lateral; visible from above and below (more prominent); diameter 32% of head length. First gill arch with 7+3 gill rakers on cerato- and epibranchial arms, respectively. Gill rakers long; pointed; widely-spaced. Pharyngeal bones in three rows. Pharyngeal teeth 4,3,2–2,3,4; robust and long; falcate.
Measurement | n | Max | Min | Mean | SD |
---|---|---|---|---|---|
SL | 20 | 46.61 | 28.76 | 38.36 | 5.41 |
Head length (%SL) | 20 | 23.78 | 18.25 | 21.18 | 1.79 |
Head depth (%HL) | 20 | 93.35 | 59.71 | 77.75 | 7.75 |
Snout length (%HL) | 20 | 40.37 | 23.10 | 31.77 | 4.69 |
Orbit diameter (%HL) | 20 | 50.35 | 36.89 | 40.27 | 3.32 |
Postorbit length (%HL) | 20 | 38.75 | 27.56 | 33.06 | 3.03 |
Inter-orbit length (%HL) | 20 | 48.23 | 27.79 | 38.10 | 5.68 |
Predorsal length (%SL) | 20 | 68.09 | 62.17 | 64.83 | 1.71 |
Prepelvic length (%SL) | 20 | 55.17 | 45.07 | 49.03 | 2.32 |
Dorsal fin Length (%SL) | 20 | 20.39 | 15.19 | 17.00 | 1.37 |
Pectoral fin length (%SL) | 20 | 25.04 | 21.60 | 22.90 | 1.00 |
Pelvic fin length (%SL) | 20 | 14.25 | 11.80 | 12.79 | 0.68 |
Anal fin length (%SL) | 20 | 18.45 | 14.38 | 16.41 | 1.12 |
Body depth (%SL) | 20 | 25.64 | 18.39 | 21.81 | 1.91 |
Body width (%SL) | 20 | 13.27 | 9.39 | 11.11 | 1.19 |
Caudal peduncle length (%SL) | 20 | 16.64 | 11.13 | 13.95 | 1.52 |
Caudal peduncle depth (%SL) | 20 | 9.84 | 7.13 | 8.18 | 0.79 |
Meristics | n | Range | |||
Dorsal-fin rays | 20 | ii+7 (n = 3), ii+8 (n = 17) | |||
Anal-fin rays | 20 | iii+14 (n = 4), iii+15 (n = 9), iii+16 (n = 7) | |||
Pectoral-fin rays | 20 | i+9 (n = 10), i+10 (n = 8), i+11 (n = 2) | |||
Pelvic-fin rays | 20 | i+7 (n = 19), i+8 (n = 1) | |||
Lateral line scales | 2 | 49 (n = 1), 51 (n = 1) | |||
Caudal peduncle scale | 2 | 14 (n = 1), 16 (n = 1) | |||
Scale rows lat. line-dorsal | 2 | 11 (n = 2) | |||
Scale rows lat. line-pelvic | 2 | 2 (n = 2) | |||
Scale rows lat. line-anal | 2 | 2 (n = 2) | |||
Total vertebrae | 12 | 36 (n = 1), 38 (n = 3) | |||
Abdominal vertebrae | 12 | 17 (n = 1), 18 (n = 1), 19 (n = 10) | |||
Caudal vertebrae | 12 | 19 (n = 3), 20 (n = 8), 21 (n = 1) | |||
Rib pairs | 12 | 13 (n = 3), 14 (n = 7), 15 (n = 2) |
Scales small to medium relative to body size; in regular rows; cycloid, slightly elongated; radially striate. Base of anal fin lacking sheath of enlarged, elongate scales. Lateral line present; complete; dipping drastically towards ventral at tip of pectoral fin; joins midline at posterior of caudal peduncle; scale count 49–51 (n = 2) along lateral line, 14–16 around caudal peduncle.
Live colouration
(Fig. 6). Body without vertical bars or bands. Dorsum transparent pale brown with melanophores concentrated around dorsal fin; midline silver. Snout with dense dark spotting on tip. Operculum entirely metallic silver. Iris dark to light grey. Dorsal fin membrane clear; rays clear; melanophores fading towards tips. Caudal fin membrane clear to pale orange towards midline; rays dark grey, lighter towards tips; melanophores small, dark, fading towards rear. Anal fin rays clear; membrane clear; pale orange spotting above origin; melanophores few to absent. Pectoral fin membranes clear; rays clear; first ray few dark melanophores. Pelvic fin rays clear; membrane clear.
Preserved colouration
(Fig. 7). Body and head orange with small dark brown spotting along dorsal surface, midline and above anal fin. Scales on dorsal surface lightly pigmented. Ventral scale pigmentation less intense than dorsal. Dorsal surface of head lightly pigmented. Melanophores small, dark; grouped on rear of head, below orbit, and on lips and snout; along midline, increasing in intensity to caudal fin; brownish on dorsal surface, darkening between origin of pectoral and dorsal fin; forming small dark line above anal fin. Membranes between fin rays clear. Pelvic fin clear membranes and rays.
Etymology
‘Gariepinus’ refers to the Gariep, a San name for the Orange River that means ‘Great water’.
Distribution
South Africa, Namibia: Lower Orange River system, Fish River (Barnard 1943[1]).
Type locality
Orange River and Fish River, Namibia (Barnard 1943[1]).
Biology
This shoaling fish favours open, shallow water, normally occurring in slack pools and particularly below riffles. Populations found in the lower Orange and Fish Rivers are limited by the Augrabies and Fish River Falls. They are thought to feed mainly on small autochthonous invertebrates (planktonic crustaceans or insects), and are caught in large numbers where they occur. They are restricted to turbid waters, which provide protection from visual predators (R. Bills, pers. obs.).
Remarks
The two syntypes of Engraulicypris gariepinus Barnard, 1943 were originally stored in the South African Museum, but were moved to the Albany Museum, Grahamstown, South Africa (AMG 106 and 1009) (Eschmeyer 2014). The Albany Museum fish collection has now been moved to SAIAB and these specimens have not been traced (I.R. Bills, pers. obs.). There is no ‘exceptional need’ (ICZN, Articles 75.2 and 75.3) for a neotype, since there is only one species of Mesobola in the topotypical river system, and the species is sufficiently physically distinctive that even if another species was introduced, they would be easy to distinguish on the basis of published descriptions.
Taxon Treatment
- Riddin, M; Bills, I; Villet, M; 2016: Phylogeographic, morphometric and taxonomic re-evaluation of the river sardine, Mesobola brevianalis (Boulenger, 1908) (Teleostei, Cyprinidae, Chedrini) ZooKeys, (641): 121-150. doi
Images
|
Other References
- ↑ 1.0 1.1 Barnard K (1943) Revision of the indigenous freshwater fishes of the S.W. Cape region. Annals of the South African Museum 36: 101–262. http://www.biodiversitylibrary.org/part/76427#/summary