Sempach Whitefish

description

Description. Shape: Generally, deep bodied with greatest body depth anterior of dorsal fin. Dorsal profile from tip of snout to anterior origin of dorsal fin strongly convex and ventral profile moderately convex or almost straight from interorbital area to pelvic fin origin. Head short. Mouth short, wide and sub-terminal. Rostral plate pronounced. Tip of snout blunt. Large eye with a thick and sickle cell-shaped eye-socket. Pectoral fin moderately tapered and short. Dorsal fin long. Caudal peduncle stout and short. Meristics: Many but rather short gill rakers. Colour: Pigmentation of fins and body overall strong with a silvery appearance along the flanks and dorsally above the lateral line the silvery appearance changes to a greenish blue colour (based on preserved specimens and by the description by Fatio (1890)). The dorsal part of the head and the snout around the nostrils is strongly pigmented. Preserved fish are brownish in colouration.

A taxonomic revision of ten whitefish species from the lakes Lucerne, Sarnen, Sempach and Zug, Switzerland, with descriptions of seven new species (Teleostei, Coregonidae)

diagnosis

Diagnosis. Coregonus suidteri is a large whitefish species with strong pigmentation of all fins and the body; greenish blue colour on the flanks above the lateral line; deep bodied (body depth: 25.4 and 29 % SL); blunt snout; short head (20 and 22 % SL); sub-terminal mouth; moderately large eye (eye diameter: 21.9 and 23.9 % HL) with a thick (4.5 and 6.5 % HL) and triangular-shaped eye socket; short and stout caudal peduncle (caudal peduncle depth: 7.8 and 8.7 % SL; caudal peduncle length: 13.3 and 13.5 % SL); many but rather short gill rakers (longest gill raker: 9.1 % HL; total gill raker number: 35).

A taxonomic revision of ten whitefish species from the lakes Lucerne, Sarnen, Sempach and Zug, Switzerland, with descriptions of seven new species (Teleostei, Coregonidae)

distribution

Distribution and notes on biology. Coregonus suidteri is found in Lake Sempach. Coregonus suidteri was previously thought to naturally occur in several lakes in Switzerland, namely lakes Lucerne, Zug, Sempach, Hallwil and Baldegg. Independent multilocus microsatellite (Suppl. material 1: figs S 2, S 3) and large genomic AFLP (Hudson et al. 2011) data sets have shown that C. suidteri is composed of multiple species endemic to different lakes in Switzerland. Both population-based neighbour-joining tree's and individual-based population structure analysis suggest that contemporary samples of whitefish from Lake Zug, Sempach and Lucerne group into independent genetic clusters (Suppl. material 1: figs S 2, S 3; Hudson et al. 2011). The status of the extinct species C. cf. suidteri from lakes Hallwil and Baldegg is unresolved since no genetic material is present to date. The extant population of Lake Sempach whitefish on which these independent multilocus microsatellite and large genomic AFLP analyses are based on, show strong signals of genetic association with whitefish from Lake Zug and Lake Lucerne. As has been noted before for the other lakes in this study (and many more lakes in Sw

A taxonomic revision of ten whitefish species from the lakes Lucerne, Sarnen, Sempach and Zug, Switzerland, with descriptions of seven new species (Teleostei, Coregonidae)

materials_examined

Comparative material. All the fish detailed below were collected from Switzerland, Lake Constance. They are illustrated in Fig. 13 and listed in Tables 9, 12 - 14.

A taxonomic revision of ten whitefish species from the lakes Lucerne, Sarnen, Sempach and Zug, Switzerland, with descriptions of seven new species (Teleostei, Coregonidae)