Thrissops cirinensis Nybelin, 1964

Ebert, Martin, 2025, New species of the genus Thrissops (Teleostei, Ichthyodectiformes) in the Upper Jurassic of the Solnhofen-Archipelago (Germany) and Kimmeridge Clay (England), Zitteliana 99, pp. 1-32 : 1-32

Thrissops cirinensis Nybelin, 1964

1964 Thrissops subovatus cirinensis Nybelin : p. 14–16; pl. 4, fig. 2; pl. 5, fig. 4.

1977 Thrissops cirinensis Nybelin ; Taverne: figs 4, 8.

2013 Thrissops cirinensis Nybelin ; Ebert and Kölbl-Ebert: tab. 1; fig. 5.

2024 Thrissops cirinensis Nybelin ; Ebert: fig. 13.8.

Holotype.

MNHN CRN 66 (Fig. 7 ), complete specimen in lateral view, 18.5 cm standard length (SL) .

Type locality.

Cerin, France. The location of Cerin is marked with a question mark on the rock slab of the holotype. The rock is also somewhat unusual for the Plattenkalk of Cerin. However, this problem must be left to future research.

Diagnosis

(amended from Nybelin 1964 and Taverne 1977). teeth in premaxilla and dentary larger than in other Thrissops species; 32 supraneurals; 27 anal pterygiophores; 54 vertebrae (without ural centra); 24 ribs.

Remark.

Nybelin (1964) was somewhat cautious about calling this taxon a new species, since there was only a single specimen and that could be pathological. Taverne (1977) finally determined the species name Thrissops cirinensis .

Further specimens from Cerin

(probably belonging to the same species): MHNL 20150008, 20150311, 20150312, 20150313 (counterpart of 20150311), 20150401, 20150661, 20150690, 20150736, 20150831; UCBL -FSL P 371, 502407, 502412.

All these specimens are poorly preserved and it is impossible to say for sure if they are specimens of Thrissops cirinensis . More detailed examinations under optimal UV light may help. These specimens are similar to the holotype of Th. cirinensis mainly in the following features: short length of the body (compared to other Ichthyodectiformes ); the body shape with SL / BD 27–33 %; the number of 30–31 supraneurals; 23–26 anal pterygiophores; ~ 49–51 vertebra and 24–25 abdominal ribs (for measurements of specimens see Suppl. material 1: table S 1). In UCBL -FSL P 371 some large teeth in the praemaxilla and in UCBL -FSL 502412 some larger teeth in the dentary, typical for Th. cirinensis , are visible.

Figures

Figure 7. Thrissops cirinensis Nybelin 1964 holotype (MNHN CRN 66) from the Upper Jurassic of Cerin, France.