Paramblypterus, SAUVAGE, 1888

Štamberg, Stanislav, 2021, Actinopterygians Of The Broumov Formation (Permian) In The Czech Part Of The Intra-Sudetic Basin (The Czech Republic), Fossil Imprint 77 (1), pp. 73-101 : 86

Paramblypterus cf. rohani

Text-figs 8b, c , 9–12

M a t e r i a l. 210 fragments of bodies and isolated bones from the localities of the Otovice Limestone Horizon (Textfig. 1b).

R e m a r k s. Paramblypterus rohani (HECKEL in HECKEL et KNER, 1861) was first described from the Vrchlabí

Formation (Asselian) of the Krkonoše Piedmont Basin ( Heckel and Kner 1861, Fritsch 1895, Heyler 1969, Štamberg 1976). Heyler (1971) also documented this species from the Autun Basin in the French Massif Central. Numerous anatomical features such as the skull roof bones, maxilla and bones of the cheek correspond with the features described by Dietze (1999) in Paramblypterus duvernoyi ( AGASSIZ, 1833). It is likely that the species Paramblypterus rohani belongs within a synonymy of Paramblypterus duvernoyi ( Dietze 1999, Štamberg 2018). However, a thorough comparison of the two species has not yet been made and the species Paramblypterus rohani is still kept as valid. For this reason, the material described in the following article is compared with the specimens of Paramblypterus rohani known from the Vrchlabí Formation of the Krkonoše Piedmont Basin.

D e s c r i p t i o n. Bodies of fusiform shape and a total length up to 172 mm. None of studied specimens had a complete undeformed body shape ( Text-fig. 8b, c ). Body fragments exhibited the slightly arched anterior part of the body ( Text-fig. 10f ).

Rostral part and skull roof ( Text-figs 9 , 10a–d ). A large postrostral with short ridges and tubercles on the outer surface of the bone is preserved in specimen DP 4529. A ragment of the nasal and supraorbital anterior is situated laterally from the postrostral.

The skull roof bones are preserved in the specimens NM-M 4920 , P 64658, P 64665, P 64673 and others. The frontal is of oblong shape, the length being more than twice the width including the lateral process .

The anterior edge of the frontal is straight or slightly slopes medially, the lateral edge of the bone forms the lateral process in the posterior third of its length, the process extends between the dermopterotic and dermosphenotic. The interfrontal suture is without any large processes, and is straight or slightly wavy. The dorsal surface of the frontal bears well developed sculpture including tubercles and vermicularly arranged ridges. Prominent sculpture on the frontal sometimes overlaps the interfrontal suture ( Text-fig. 10a ). The supraorbital sensory canal traverses along the lateral margin of the frontal. The parietal is square shaped, and often the right and left parietal differ in shape ( Text-fig. 10a ). The anterior, medial and posterior pit lines are well-developed. The dorsal surface of the bone bears tubercles and short ridges. The triangular shaped dermosphenotic is slightly elongated posterolaterally along the anterior margin of the dermopterotic. Ridges which are parallel with the lateral border of the bone form the sculpture on the dermosphenotic. A short section of the infraorbital canal can be observed near to the lateral edge of the bone. The dermopterotic is oblong in shape, rounded anteriorly. It slightly extends in a posterior direction and continues as a large sharply pointed process posteriorly. The lateral edge of the bone is usually straight or slightly wavy in comparison to specimen P 30943 ( Text-fig. 10d ) which has a lateral process in the middle of the lateral edge length. Conspicuous ridges and tubercles form the sculpture similarly as on the other bones of the skull roof. The pores of the infraorbital sensory canal can be observed along the posterior part of the lateral edge of the bone. A small postparietal of oblong shape is preserved on DP 4529. A strip of extrascapular bones ( Text-fig. 9a ) which consists of the extrascapular medial and paired extrascapular

Figures

Text-fig. 8. a: Paramblypterus zeidleri (FRITSCH, 1895), Lectotype NM-M 901 from the locality Ruprechtice, scale bar 10 mm; b: Paramblypterus cf. rohani, significantly deformed specimen from the locality Otovice “Stěnava”, DP 4529, scale bar 10 mm; c: Paramblypterus cf. rohani, significantly deformed specimen from the locality Otovice “Stěnava”, DP 4257, scale bar 10 mm.

Text-fig. 9. Paramblypterus cf. rohani. Scale bars 5 mm. a, b: drawing and photograph of the skull in lateral view, locality Otovice “Stěnava”, DP 4529; c, d: photograph and drawing of the skull in lateral view, locality Otovice “Chmelnice”, P 64673; e: bones of the skull roof in dorsal view, locality Otovice “Chmelnice”, P 64656; f: bones of the skull roof in dorsal view, locality Otovice “Chmelnice”, P 30945; g, h: drawing and photograph (whitened) of the bones of the skull roof in dorsal view, locality Otovice “Chmelnice”, P 64658. Abbreviations: ap – anterior pit line, Cl – cleithrum, Cor – coronoid, Dhy – dermohyal, Dpt – dermopterotic, Dsph – dermosphenotic, Extl – extrascapular lateral, Extm – extrascapular medial, Fr – frontal, Gul – lateral gular, Gum – medial gular, ioc – infraorbital canal, Ios – infraorbital superior, Ju – jugal, mc – mandibular canal, Md – mandible, Mx – maxila, mp – medial pit line, Na – nasal, Op – operculum, Pa – parietal, Pop – preoperculum, pp – posterior pit line, Psp – postspiracular, Pt – posttemporal, Ptr – postrostral, Qu – quadratum, Rbr – branchiostegaly rays, Sbo – suborbital, soc – supraorbital canal, Sop – suboperculum, Spi – spiracular.

Text-fig. 10. Paramblypterus cf. rohani. a: the skull roof in dorsal view, locality Otovice “Chmelnice”, P 64665, scale bar 5 mm; b: bones of the skull roof in dorsal view, locality Otovice “Chmelnice”, NM-M 4920, scale bar 5 mm; c: right frontal in dorsal view, locality Otovice “Chmelnice”, NM-M 4923, scale bar 5 mm; d: right dermopterotic in dorsal view, locality Otovice “Chmelnice”, P30943, scale bar 2 mm; e: right supracleithrum in lateral view, locality Otovice “Chmelnice”, P 30944, scale bar 5 mm; f: fragment of not deformed body in lateral view, locality Otovice “Chmelnice”, NM-M 4916, scale bar 10 mm; g: right maxilla in lateral view, locality Otovice “Chmelnice”, P 64661, scale bar 5 mm; h: right maxilla in lateral view, locality Otovice “Chmelnice”, NM-M 4922, scale bar 5 mm. Abbreviations: Dpt – dermopterotic, Dsph – dermosphenotic, Fr – frontal, Pa – parietal.

Text-fig. 11. Paramblypterus cf. rohani. Arrows indicate directio cranialis. Scale bars 5 mm. a: isolated maxilla, cleithrum and supracleithrum in lateral view, locality Otovice “Chmelnice”, P 64661; b: left posttemporal in dorsal view, locality Otovice “Chmelnice”, P 64664; c: right operculum in lateral view, locality Otovice “Chmelnice”, P 64883; d: anal fin, locality Otovice “Stěnava”, DP 4529; e: dorsal fin, locality Otovice “Chmelnice”, NM-M 4916. Abbreviations: Cl – cleithrum, Mx – maxilla, Scl – supracleithrum.

Text-fig. 12. Paramblypterus cf. rohani. Arrows indicate directio cranialis. a, b: photograph and drawing of four ridge scales in front of the dorsal fin base, locality Otovice “Chmelnice”, P 80178, scale bars 5 mm; c: scale rows from the area between the pectoral and pelvic fins, outer surfaces of the scales bear fine ridges terminating as denticles on the posterior edge of the scales, locality Otovice “Chmelnice”, NM-M 4916, scale bar 5 mm; d: isolated scale, from anterior area of the lateral side of the body, with denticulated posterior edge, locality Otovice “Chmelnice”, P 30945, scale bar 2 mm; e: isolated scale from the pelvic area of the body, locality Otovice “Chmelnice”, P 30945, scale bar 2 mm; f, g: drawing and photograph of the postcleithrum and the scales behind the pectoral girdle (the scales bear conspicuous ridges on their outer surface; well preserved large postcleithrum is without ridges.), locality Otovice “Chmelnice”, NM-M 4915, scale bars 5 mm. Abbreviations: Cl – cleithrum, Pcl – postcleithrum, Scl – supracleithrum.