Anatopus palmatus ” Lapparent & Montenat, 1967

Moreau, Jean-David, Vullo, Romain, Bichr, Elsie, Thomas, Jérôme, Gand, Georges, Gagnaison, Cyril, Barrier, Pascal & Néraudeau, Didier, 2024, Crocodylomorph and dinosaur tracks from the lowermost Jurassic of Le Veillon (western France): ichnotaxonomic revision of the type material (Lapparent collection), Geodiversitas 46 (8), pp. 343-366 : 353

“ Anatopus palmatus ” Lapparent & Montenat, 1967 (nomen dubium)

( Fig. 6 )

Anatopus palmatus Lapparent & Montenat, 1967: 27-29 , pl. XII.3, fig. 16.

EXAMINED MATERIAL. — Holotype: ULB-04C15_B . — Other specimens: ULB-04C10_C , ULB-04C15_C .

DESCRIPTION

The material includes three, isolated and very poorly preserved tracks. Tracks ULB-04C15_B ( Fig. 6 A-C) and ULB-04C15_C ( Fig. 6 D-F) are tridactyl whereas ULB-04C10_C is a partial footprint and only preserves two traces of digits. Lapparent & Montenat (1967) included tracks with two kinds of morphologies in this ichnotaxon.

ULB-04C15_B is small-sized and wider than long (L = 8.5 cm, W = 9.5 cm; Fig. 6 A-C; Table 2 ). The trace of digit III shows a long free part (L/D = 1.6). Impressions of digits are thin, elongated, separated and apically sharp. The impression of digit III is markedly longer than traces of digits II and IV that are not fully impressed (proximal part not marked). Marks of claws are well marked. They are oriented outward on traces of digits II and IV.

ULB-04C15_C is small-sized, 7.5 cm wide ( Fig. 6 D-F; Table 2 ). Even if the proximal part of ULB-04C15_C is broken, the footprint is longer than wide. The trace of digit III is thin, elongated, shows a long free part and rounded to oval phalangeal pads. The divarication angle II-IV is 55°.

REMARKS

Lapparent & Montenat (1967) justified the erection of “ Anatopus palmatus ” (without establishing its diagnosis) by 1) the occasional presence of a skin mark forming a web between tracks of digits II, III and IV; and 2) traces of digits II and IV very short compare to digit III ( Fig. 6A, B ). Lapparent & Montenat (1967) indicated that only the holotype (ULB-04C15_B; Fig. 6 A-C) shows the mark of a web. After reinvestigation of the holotype, we are not convinced by the description of Lapparent & Montenat (1967) ( Fig. 6B, C ). The structure considered by Lapparent & Montenat (1967) as the border of a web clearly shows a sedimentary origin (structure propagated beyond the track). The holotype of “ Anatopus palmatus ” consists of an undertrack, explaining why the marks of digits II and IV are so short. The sketch of ULB-04C15_C proposed in fig. 16B1 of Lapparent & Montenat (1967) does not correspond to the morphology of the track, which actually looks more like a grallatorid footprint; however, it is too poorly preserved for a specific attribution. We thus consider “ Anatopus palmatus ” as a nomen dubium.

Figures

FIG. 6. — “Anatopus palmatus” Lapparent & Montenat, 1967, that is here invalidated: A-C, ULB-04C15_B (holotype of “A. palmatus”), photograph (A), interpretative sketch of Lapparent & Montenat (1967: fig. 16A and pl.XII.3) (B), and our interpretation (C); D-F, ULB-04C15_C, photograph (D), interpretative sketch of Lapparent & Montenat (1967: fig. 16B1) (E), and our interpretation (F). Scale bars: 5 cm.