Phalangichnus gagoli, Ptaszyński & Niedźwiedzki, 2004

Ptaszyński, Tadeusz & Niedźwiedzki, Grzegorz, 2004, Late Permian vertebrate tracks from the Tumlin Sandstone, Holy Cross Mountains, Poland, Acta Palaeontologica Polonica 49 (2), pp. 289-320 : 308-311

Phalangichnus gagoli ichnosp. nov.

Figs. 25A–D , 26A–F , 27A–D , 28A–H .

Palmichnus sp. Ptaszyński, 2000b: fig. 4 (right part of the photograph), fragmentary trackway described in this paper as Muz. PIG OS−220/33: 1–4.

Holotype: Set of pedal and manual imprints Muz. PIG OS−222/1: 3, 4 ( Figs. 25C , 26F , 27C , 28A ).

Type locality: Tumlin Gród quarry, 11 km NW of Kielce, Holy Cross Mts., Poland.

Type horizon: Tumlin beds, Lower Buntsandstein, uppermost Permian.

Derivation of the name: In honour of Jerzy Gągol, researcher of the Holy Cross Mountains Buntsandstein lithostratigraphy.

Material.—Tumlin quarry: Muz. PIG OS−222/1: 1–6 three consecutive sets of pedal and manual imprints ( Figs. 25C , 27C ); the second set of them, Muz. PIG OS−222/1: 3 (left pedal imprint) and Muz. PIG OS−222/1: 4 (left manual imprint) are designated as the holotype ( Figs. 26F , 28A ); Muz. PIG OS−222/1: 7–18 six consecutive pedal and manual imprints ( Figs. 25C , 26E , 27D , 28B ); Muz. PIG OS−222/1: 19–26 four sets of imprints; Muz. PIG OS−222/1: 29–44 trackway, somewhat irregular composed of at least eight sets ( Figs. 25A , 26B–D , 27B , 28C, F, H ); Muz. PIG OS−222/1: 45–56 six sets of imprints ( Figs. 25B , 27A , 28D ); Muz. PIG OS−222/1: 57, 58 isolated set of left pedal and manual imprints ( Figs. 26A , 28G ); Muz. PIG OS−222/1: 27, 28 isolated imprints from the poorly preserved trackway being parallel to that of Muz. PIG OS−222/1: 29–44 ( Fig. 25A ); Muz. PIG OS−222/1: 59–64 four sets of consecutive pedal and manual imprints ( Fig. 25D ); Muz. PIG OS−220/33: 1–4 two sets of right pedal and manual imprints; Muz. PIG OS−220/73: 42, 43 isolated set of pedal and manual imprints; Muz. PIG OS−220/73: 44–49 three consecutive pedal and manual imprints; Muz. PIG OS−220/40: 1–4 two consecutive sets of pedal and manual imprints.

Diagnosis.—Small Phalangichnus with differentiated trackway features: pedal pace angulation ranging from 83° up to 120°; respective manual values vary from 110° up to 147°. Manus may be situated before the pes, on the same line, or may be overstepped by the latter, which is interpreted as connected with a differentiated kind of the gait. Pedal digit V small, long as like as the II. Divarication of pedal digits I–IV attains 42°. The stride/pedal length ratio ranges from 4.6 up to 8.3.

Description.—Trackway. Most of trackways described were obtained from the Tumlin beds and came mainly from the large slab exhibited in front of the building of the Holy Cross Branch of the Polish Geological Institute, Kielce. The most characteristic feature of these trackways is the varied degree of overstepping of pes imprints by those of manus. On the same slab, different trackways show manus imprints situated before pes ones (Muz. PIG OS−222/1: 57, 58; Muz. PIG OS−222/1: 27–44; Muz. PIG OS−222/1: 19–26, Figs. 25A , 26A–C , 27B , 28C, F–H ); more or less on the same line (Muz. PIG OS−222/1: 45–56; Muz. PIG OS−220/33: 1–4, Figs. 25B , 26D , 27A , 28D ) and show manual imprints overstepped by those of pes (Muz. PIG OS−222/1: 1–6; Muz. PIG OS−222/1: 59–64, Figs. 25C, D , 26E, F , 27C, D , 28A, B ). Those features are interpreted as results of differentiated speed (walking and running gait) of animals. Pedal imprints diverge out from the midline at –3° up to –23°; those of manus are inclined to the midline from 0° up to +32°. The pedal stride is strongly variable, as is the pace angulation, ranging from 150 mm up to 290 mm. The pedal pace width ranges from 85–105 mm, while the pedal one is 47–65 mm. The stride/pedal length ratio ranges from 4.6 up to 8.3.

Pes.—All five digits have claw marks. The digit group I–IV is triangular in outline. The average length and width of the digit group I–IV of many specimens from the slab Muz. PIG OS−222/1 is 29 mm and 24 mm, respectively. The maximum known length of this group is up to 40 mm (specimens Muz. PIG OS−220/73: 44, 46). Digits are closely arranged, with typical length proportions: IV>III>II>I, showing average values: 13, 17, 21, 25 mm, respectively with total divarication of digits II–IV of 25°, and I–IV of 42°. Digit V is long as like as digit II, situated somewhat posteriorly and laterally to the digit group I–IV; in many footprints well visible.

Manus.—Manus imprints smaller than pes ones. The length of manus imprints only somewhat exceeds their width, attaining average values 25 and 24 mm. All digits from group I–IV have claw marks and increase in length from I to IV: 11, 16, 18, and 20 mm, respectively. Average divarications of digits I–IV, II–IV, and I–V are 38, 22, and 80°, respectively. Digit V is about 13.5 mm long.

Discussion.— Phalangichnus gagoli ichnosp. nov. differs from Phalangichnus alternans in smaller manual pace width than that of pes, which are almost equal in Phalangichnus alternans . Phalangichnus gagoli ichnosp. nov. is somewhat smaller in size. Manual imprints of P. gagoli ichnosp. nov. are distinctly narrower than those of P. alternans , having relatively smaller pedal imprints in relation to manual ones than in the latter. All known trackways of P. gagoli show pace angulation bigger than P. alternans . The comparison of Phalangichnus gagoli ichnosp. nov. with P. simulans is difficult because of the unsatisfactory state of preservation of the latter and means that track features might be erroneously interpreted (see discussion above).

Phalangichnus gagoli ichnosp. nov. shows a pace angulation greater than 90°, much more than that of Phalangichnus simulans , if the interpretation of its trackway given by Schmidt (1959) and Haubold (1971b, 1984) is correct. It shows axes of pedal imprints more closely situated to the midline and manual axes are distinctly inclined to it. It is somewhat difficult to compare the track features of Phalangichnus gagoli ichnosp. nov. with Phalangichnus perwangeri Conti et al., 1977 because of the lack of exactly specified determined trackway features of the latter. In this case there is also a possibility of erroneous interpretation of material from Val Gardena. It is possible that specimens visible on the slab with the holotype of Phalangichnus perwangeri ( Conti et al. 1977: fig. 10, pl. 2) have been made by at least two animals walking along almost the same line. Phalangichnus gagoli ichnosp. nov. shows pedal axes less diverged from the midline; less differentiated pedal digits lengths and quite different outline of manual imprints, being narrower and showing in opposition to those of pes, greater differences of digits lengths. Trackway features of Phalangichnus gagoli ichnosp. nov. differ greatly from those of Phalangichnus perwangeri interpreted by Conti et al. (1977). In comparison with Phalangichnus perwangeri , Phalangichnus gagoli ichnosp. nov. is smaller and shows lesser divarication of digits I–V, about 90°. If the trackway interpretation by Conti et al. (1977) is correct, Phalangichnus gagoli ichnosp. nov. shows much bigger pace angulation in trackways with manual imprints situated in similar position to those of pes as in P. perwangeri . P. gagoli ichnosp. nov. can be compared with problematic ichnospecies P. simulans interpreted as trackways of two individuals with manual imprints overstepped by pedal ones, similarly as in specimens Muz. PIG OS−222/1: 29–44 and Muz. PIG OS−222/1: 27, 28 ( Figs. 25A , 27B ).

In connection with the possible narrower manual width of pace in relation to the pedal one, and existence of overstepping, P. simulans is not a synonym of P. alternans (see Fichter 1983b).

In our opinion P. simulans and P. alternans represent different ichnospecies, but both need re−examination. All five ichnospecies together with P. perwangeri , P. gagoli ichnosp. nov. and P. gradzinskii ichnosp. nov. represent a branch of reptiles that show track features developed in the Triassic in Rhynchosauroides representatives. There are two main morphological types of Phalangichnus : the smaller, with manual width of pace much narrower than the pedal one, with manual imprints overstepped by pedal ones during speed gait, represented by P. simulans , P. perwangeri , and P. gagoli ichnosp. nov. and the bigger one, with manual and pedal width of pace close one to another, have never observed with manual imprints overstepped by pedal ones, represented by P. alternans and P. gradzinskii ichnosp. nov.

Figures

Fig. 25. Phalangichnus gagoli ichnosp. nov. A. Muz. PIG OS−222/1: 29–41 long, somewhat irregular trackway composed of at least seven sets of imprints, specimens Muz. PIG OS−222/1:42–44 are also visible. B. Muz. PIG OS−222/1:47–56 five consecutive pedal and manual imprints.C. Two trackways, Muz. PIG OS−222/1: 1–6 three consecutive sets of pedal and manual imprints, the second set of imprints is designed as the holotype, Muz. PIG OS−222/1:3, 4 and Muz. PIG OS−222/1: 13–18 three consecutive sets of imprints. D. Muz. PIG OS−222/1: 59–62 two consecutive sets of imprints. Scale bars 5 cm.

Fig. 26. Phalangichnus gagoli ichnosp. nov. A. Muz. PIG OS−222/1: 57, 58 set of pedal and manual imprints. B. Muz. PIG OS−222/1: 43, 44 set of pedal and manual imprints. C. Muz. PIG OS− 222/1: 29, 30 set of pedal and manual imprints. D. Muz. PIG OS−222/1: 35, 36 set of pedal and manual imprints. E. Muz. PIG OS−222/1: 15, 16 set of pedal and manual imprints. F. Muz. PIG OS−222/1: 3, 4 set of pedal and manual imprints, holotype. Scale bars 5 cm.

Fig. 27. Phalangichnus gagoli ichnosp. nov. A. Muz. PIG OS−222/1: 47–56 five consecutive pedal and manual imprints. B. Muz. PIG OS−222/1: 29–43 eight consecutive sets of imprints; among them imprints (not numbered) of other fragmentary trackways made almost along the same line. C. Muz. PIG OS−222/1: 1–6 three consecutive sets of pedal and manual imprints; the second set of imprints is designed as the holotype. D. Muz. PIG OS−222/1: 13–18 three consecutive sets of imprints. Scale bars 5 cm.

Fig. 28. Phalangichnus gagoli ichnosp. nov. A. Muz. PIG OS−222/1: 3, 4 set of pedal and manual imprints, holotype. B. Muz. PIG OS−222/1: 15, 16 set of pedal and manual imprints. C. Muz. PIG OS−222/1: 35, 36 set of pedal and manual imprints. D. Muz. PIG OS−222/1: 53, 54 set of pedal and manual imprints. E. Muz. PIG OS−222/1: 55, 56 set of pedal and manual imprints. F. Muz. PIG OS−222/1: 29, 30 set of pedal and manual imprints. G. Muz. PIG OS−222/1: 57, 58 set of pedal and manual imprints. H. Muz. PIG OS−222/1: 43, 44 set of pedal and manual imprints. Scale bars 5 cm.