Baissa (PIN collection 4210, layer 35) (Cretaceous of Russian Federation)

Where: Buryatia, Russian Federation (53.3° N, 112.1° E: paleocoordinates 56.0° N, 108.5° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Zaza Formation, Aptian (125.0 - 113.0 Ma)

• C. longipoda, E. trisetalis and Lycoptera all occur in the Zaza Formation indicating that this formation could be correlated with the upper Yixian Formation and the lower Jiufotang Formation in western Liaoning, which have a duration of 122.5-120 Ma. So it is possible to assign the Zaza Formation to an Aptian age. Also correlated with Barremian-Aptian based on plants and pollen.

Environment/lithology: lacustrine - large; lithified siltstone and lithified marl

• "The water body is reconstructed as an intermontane lake with the depth of 20 - 30 meters (LYAMINA 1980) situated within a granite massif. The presence of thick layers of the bituminous shales shows that the lake was meromictic, with the oxygen deficiency and high hydrogen sulphur level in the hypolimnion. However, the oxygenated epilimnion should be thick, with a lower boundary well beneath the limit of episodic wave action because no suffocation events are documented. The abundance of caddisflies, dobsonfly larvae and other groups intolerant to oxygen deficiency shows that in more shallow areas the water was clear and well-oxygenated even near the bottom. The lake ecosystem was highly productive as indicated by its complex trophic structure (Fig. 2) with several levels of predators up to the large sturgeon-like fish Stychopterus as well as by the extremely high abundance of planetonivorous phantom midges (SINICHENKOVA & ZHERIKHIN 1996)." ZHERIKHIN et al., 1999

Size classes: macrofossils, mesofossils

Preservation: mold/impression

Reposited in the PIN

Primary reference: J. Koteja. 1988. Eomatsucoccus n. g. (Homoptera, Coccinea) from Siberian Lower Cretaceous deposits. Annales Zoologici 42:141-163 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 113353: authorized by Matthew Clapham, entered by Matthew Clapham on 28.07.2011, edited by Lindy Edwards and Jered Karr

Creative Commons license: CC BY (attribution)

Taxonomic list

Insecta
 Dicondylia - Saurodectidae
Saurodectes vrsanskyi n. gen. n. sp.6
Saurodectes vrsanskyi n. gen. n. sp.6 Rasnitsyn and Zherikhin 1999 winged insect
PIN 4210/7056
 Hemiptera - Matsucoccidae
Eomatsucoccus popovi n. sp. Koteja 1988 pine bark scales
PIN 4210/1102
 Hemiptera - Palaeoaphididae
Ellinaphidinae indet.2 Kania and Wegierek 2008 aphid
PIN 4210/2838, 7612
Ellinaphis longistigma2 Kania and Wegierek 2008 aphid
PIN 4210/2831, 2832, 2833, 7613
Ellinaphis incognita2 Shaposhnikov 1979 aphid
PIN 4210/2841
Ellinaphis extenda2 Kania and Wegierek 2008 aphid
PIN 4210/2835
 Hemiptera - Szelegiewicziidae
Tinaphis laticubitus n. gen. n. sp.7 Wegierek 1989 aphid
PIN 4210/2849
Brimaphis certa7 Wegierek 1989 aphid
PIN 4210/2839
 Hymenoptera - Ichneumonidae
Palaeoichneumon mirabilis n. sp.3 Kopylov 2009 ichneumon wasp
PIN 4210/1155
 Diptera - Ironomyiidae
"Hermaeomyia armata" = Palaeopetia armata4
"Hermaeomyia armata" = Palaeopetia armata4 Mostovski 1995 ironic fly
PIN 4210/3089
 Diptera - Platypezidae
Parnasos firmipes5 Mostovski 1995 flat-footed fly
PIN 4210/3100
 Diptera - Mycetophilidae
Palaecomoptera longimedia1 Blagoderov 1997 fungus gnat
PIN 4210/2977