Baissa (PIN collection 4210, layer 25) (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, carbonaceous 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: V. N. Makarkin. 1997. Fossil Neuroptera of the Lower Cretaceous of Baisa, east Siberia. Part 3. Chrysopidae (Insecta). Spixiana 20:107-118 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 122551: authorized by Matthew Clapham, entered by Matthew Clapham on 03.01.2012, edited by Lindy Edwards and Jered Karr

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Insecta
 Diptera - Mycetophilidae
Palaecomoptera longimedia1
Palaecomoptera longimedia1 Blagoderov 1997 fungus gnat
PIN 4210/2957
 Diptera - Ironomyiidae
Hermaeomyia saeticaudata n. sp.3
Hermaeomyia saeticaudata n. sp.3 Mostovski 1995 ironic fly
PIN 4210/3087
 Hemiptera - Oviparosiphidae
"Oviparosiphum baissensis" = Archeoviparosiphum baissense4
"Oviparosiphum baissensis" = Archeoviparosiphum baissense4 Shaposhnikov and Wegierek 1989 aphid
Could be from PIN 3064
 Hemiptera - Palaeoaphididae
Ellinaphidinae indet.2, Rinorectuaphis connexa2, Caudaphis angustivola2
Ellinaphidinae indet.2 Kania and Wegierek 2008 aphid
PIN 4210/2775, 2780, 2781, 3568
Rinorectuaphis connexa2 Kania and Wegierek 2008 aphid
PIN 4210/2776
Caudaphis angustivola2 Kania and Wegierek 2008 aphid
PIN 4210/2774, 2777, 2779
 Blattodea - Mesoblattinidae
"Piniblattella altera" = Archimesoblatta altera6
"Piniblattella altera" = Archimesoblatta altera6 Vršanský 1997 cockroach
PIN 4210/1452
 Neuroptera - Chrysopidae
Mesypochrysa angustialata n. sp.
Mesypochrysa angustialata n. sp. Makarkin 1997 green lacewing
PIN 4210/2209
 Mecoptera - Boreidae
Palaeoboreus baissicus n. sp.5
Palaeoboreus baissicus n. sp.5 Sukacheva and Rasnitsyn 1992 scorpionfly
PIN 4210/1456
1Blagoderov 1997; 2Kania and Wegierek 2008; 3Mostovski 1995; 4Shaposhnikov and Wegierek 1989; 5Sukacheva and Rasnitsyn 1992; 6Vršanský 1997