Vol 53, No 2 (2019)

One of the unique groups of skeletal organisms of the lower Cambrian is the archaeocyathids, a group restricted to the early Cambrian and showing stages of their evolution. A longitudinal section through an archaeocyathid can show ontogenetic stages from a juvenile cup to the complete development of species characters. This feature allows the study of ontogenetic changes in the group, revealing various heterochronies and other patterns that can be directly linked to evolutionary reconstructions. Archaeocyaths from various regions include a large number of damaged and deformed cups. It is shown that deformations and pathological changes originating in the Tommotian (Nochoroicyathus sunnaginicus Zone) could be manifested in the general evolution of the group.

The interior of the dorsal valve of Semiplanella carinthica Sarytcheva et Legrand-Blain, 1977 is described. The location of the bases of brachial loops and adductor muscles is reconstructed. The unusual arrangement of the adductor scars and brachial loops developed in the result of their rotation that was caused by a strong torsion of the shell and necessity to raise the anterior shell margin over the valve bottom. Similarly structured brachial loops and partly cardinal process is known for Beleutella Litvinovich, 1967 and possibly Talasoproductus Litvinovich et Vorontsova, 1983. These three genera are suggested to be united into a new tribe Semiplanellini tribe nov. of the subfamily Gigantoproductinae.

A new genus Kzylcader gen. nov. (Hemiptera: Heteroptera: Tingidae) with Sinaldocader rasnitsyni Golub et Popov, 2012 as a type species and four new species (K. ovatus sp. nov., K. angustatus sp. nov., K. shcherbakovi sp. nov., and K. strigosus sp. nov.) are described from the Upper Cretaceous (Turonian) of Southwestern Kazakhstan (Kzyl-Dzhar locality). The description of K. rasnitsyni is updated. A key to the Kzylcader species is given. Sinaldocaderini trib. nov. is established in the subfamily Cantacaderinae for the genera Sinaldocader Popov, 1989 and Kzylcader gen. nov. Similarities of Kzylcader gen. nov. to Thaumastocoridae are indicated.

Two new species of the recent genera of hooked-horn sculpins (Pisces, Cottidae, Artediellinae) are described from Miocene deposits (Serravalian–Tortonian) of the Agnevo Formation, Sakhalin Island, Russia. This is the first record of fossil skeletal remains of members of the subfamily Artediellinae. The Miocene hooked-horn sculpins are similar to modern fishes of this subfamily in the main countable characters and body proportions, but differ in a number of primitive features, such as the presence of skin spinules, covering the body up to the caudal fin base, and the presence of spines on the posterior edge of the lateral line scales.

Postcranial skeletal morphology of the Oligocene-Miocene fossil galliform genus Palaeortyx is compared with modern representatives of Phasianoidea. In particular, Palaeortyx is compared with the modern African Ptilopachus, which was recently transferred to the American family Odontophoridae, to which Palaeortyx was originally assigned. It is shown here that Palaeortyx lacks derived features of Odontophoridae, and all the apparent similarities (including the deep fossa pneumotricipitalis dorsalis of the humerus) represent plesiomorphies of the clade Odontophoridae+Phasianidae or even a higher clade. No essential similarity between Palaeortyx and Ptilopachus can be observed. The greater similarity between Palaeortyx and Rollulinae is here considered as being plesiomorphic for Phasianidae s.s. It is thus concluded that Palaeortyx most likely represents a basal member of the Phasianidae and diverged before the Rollulinae and Phasianinae dichotomy. The evolutionary history of this genus and of the Phasianidae in general is discussed.