Lower Cretaceous Insects

[araucaria1959]

Here are 5 insects from the lower cretaceous;

specimens 1 and 2 (pics 2a, 2b) from the Yixian Formation, Huangbangi Valley, Beipiao (~ Barremian)

specimens 3, 4 and 5 from Nova Olinda, Crato Formation, Brasilia (upper Aptian / lower Albian)

Length:

specimen 1 = 10 mm (body length)

specimen 2 = 8 mm (head to the end of the longest wing) (Diptera?)

specimen 3 = 10 mm (body length, head - tail)

specimen 4 = 21 mm (total length) (Orthoptera)

specimen 5 = 18 mm (total length) (Beetle: Dystiscidae?)

Any suggestions are appreciated!

(specimen 4 is a grasshopper, specimen 5 a beetle; but is it possible to say more about them?)

An additional question:

The small circular fossils which look like small bivalves on the Yixian specimens are conchostracans (Nestoria pissovi), but I wonder about the brownish striations on the Nova Olinda material. They are suggestive of trace fossils, but otherwise they seem to show some organic matter similar to the body fossils.They are extremely common on the plates with Crato fossils. Does someone know what they are?

Thank you very much!

araucaria1959

[CH4ShotCaller]

I have never worked on these type of fossils, my apologies for not offering advice. I have to mention that these are magnificent specimens! I enjoy seeing insect fossils, thank you for showing them! Good luck.

[piranha]

The last specimen posted looks like a possible water bug, perhaps Araripebelostomum. Attached is an unidentified larval belostomatid and a couple of suggestions on the pellet-like structures from the book "The Crato Fossil Beds of Brazil". Great assortment of insects and thanks for posting!

[DLB]

The last specimen posted looks like a possible water bug, perhaps Araripebelostomum. Attached is an unidentified larval belostomatid and a couple of suggestions on the pellet-like structures from the book "The Crato Fossil Beds of Brazil". Great assortment of insects and thanks for posting!

Crato Belostomatid.jpg Crato Pellets.jpg

I agree it's a water beetle.

[piranha]

I agree it's a water beetle.

Water beetle is the common name although the belostomatids are not actually in Coleoptera. They are described as 'true bugs' (Hemiptera).

[Joyce]

Have to say they are incredible finds. The detail is beautiful!

[araucaria1959]

Thank you very much for the help, and special thanks to Piranha!

After some searching in the literature (with regard to the Crato specimens), specimen 3 is still a mystery;

the grasshopper (specimen 4) is possibly Araripelocusta brevis (see MARTILL et al., The Crato Fossils Beds of Brazil Plate 11 g)

(due to the comparatively large eyes; short abdomen; overall form, size and proportion of the wings; and the venation pattern as

far it can be seen in my specimen and the picture in the book),

the water bug (specimen 5) is possibly a member of the Naucoridae (see MARTILL et al., Fig. 11.54e) because of the proportions of the legs:

the relative length of the proximal segment and the tiny dentation on its "upper" margin, which differs from the nymphs of

Belostomatidae where the proximal leg segment is very short)

araucaria1959

Edited March 21, 2013 by araucaria1959