Mesosperchus, Ponomarenko, 1977

Fikáček, Martin, Prokin, Alexander, Angus, Robert B., Pono, Alexander, Marenko, Yue, Yanli, Ren, Dong & Prokop, Jakub, 2012, Revision of Mesozoic fossils of the helophorid lineage of the superfamily Hydrophiloidea (Coleoptera: Polyphaga), Acta Entomologica Musei Nationalis Pragae 52 (1), pp. 89-127 : 123

† ‘ Mesosperchus ’ notatus Ponomarenko, 1977

( Figs. 102–103 , 115 )

Mesosperchus notatus Ponomarenko, 1977b: 110 .

Type locality and age. Russia, Buryat Republic, Novospasskoye village (current GPS coordinates 51.3°N 108.1°E). Ichetuy Formation, Late Jurassic, Oxfordian, 161.2–155.7 mya ( CLAPHAM 2011d).

Material examined. HOLOTYPE: PIN 3000/923 (piece only). PARATYPE: PIN 3000/912 (piece only).

Taxonomic note. Both preserved specimens lack the head and the only preserved ventral structures are prosternum and parts of abdomen. The preserved parts do not bear any apomorphy or combination of characters which would indicate the placement of the species in the Hydrophiloidea . For that reason, it is here transferred to Polyphaga incertae sedis. The superficial structure of elytra with fine transverse ridges on elytral intervals somewhat resembles some groups of the Leiodidae .

Figures

Figs. 94–103. Taxa excluded from the hydrophilid lineage. 94–99 – ‘Mesohelophorus’ mongolicus Ponomarenko, 1986 (94–95 – PIN 3152/4355, holotype, piece and counterpiece; 96, 99 – PIN 3152/4312, piece and counterpiece; 97 – same specimen, detail of head in dorsal view; 99 – head and prosternum of the holotype). 100 – ‘Mesosperchus’ angulatus Ponomarenko, 1985, holotype; 101 – ‘Mesosperchus’ schultzi Ponomarenko, 1985, holotype, piece; 102–103 – ‘Mesosperchus’ notatus Ponomarenko, 1977, holotype (102 – general view; 103 – detail of elytral structure). Scale bars: 0.5 mm.

Figs.113–119.Taxa excluded from the helophorid lineage. 113 – Helo- phoropsis brodiei (Giebel, 1856), holotype; 114 – ‘Mesosperchus’ angulatus Ponomarenko, 1985, holotype; 115 – ‘Mesosperchus’ notatus Ponomarenko, 1977, holotype; 116 – Tychon antiquum (Giebel, 1856), holotype; 117–118 – ‘Mesosperchus’ schultzi Ponomarenko, 1985, holotype, piece and counterpiece; 119 – Zetemenos sexlineatus Bode, 1953, holotype. Scale bars: 1 mm.