Identification of beetles (Coleoptera)

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13.05.2016 13:28, Barnaba

Good day to all. Using geotrups from Ossetia

To the North. In Ossetia, as far as I know, there are three species of Geotrupes proper.
Of these, G. mutator (Marscham, 1802) clearly differs in the presence of 9 longitudinal grooves from the midline of the elytra to the shoulder protrusion, while the other two species have 7 (or sometimes 6) of them. On the outer side of the male forelegs, the first two teeth are much larger than the subsequent ones and are separated by a clearly distinguishable diastema occupied by the crest-like outgrowth of the base of the second tooth (in females it may be much less pronounced). The subsequent teeth are directed sideways, approximately the same in shape and decrease in size from the 3rd to the next. It is a relatively rare thermophilic species that occurs in different biotopes, but rarely goes high into the mountains.
The remaining 2 species differ in the location of the front legs. Color and size are not significantly different. In Geotrupes spiniger (Marscham, 1802), the third prong on the outer side of the male forelegs is usually quite large and is directed downwards rather than to the side (you need to look and photograph from the side or from below; when viewed from above, it is not always clear where the top of the prong is looking, since its base is usually curved). In females and small males, as well as older specimens with erased teeth, this may be much less pronounced and sometimes difficult to determine, but still the top of the tooth is directed downward. The species is mostly steppe, although it rises in the steppe foothills.
In G. olgae (Olsoufieff, 1918), which is morphologically quite similar to G. stercorarius (of which it is sometimes still considered a subspecies), the third prong on the outer side of the male forelegs is larger than the subsequent ones, but it is directed laterally, not downwards. The latter species is the most mountainous and is usually found in the mountains at a considerable height, including in the alpika.
In your photos, it seems that the first and third are male and female G. olgae; the second may be G. mutator, but count the grooves on the elytra. In view of the above, look at the images of these species on the web, but some of them are incorrectly defined there.

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13.05.2016 15:57, maik

To the North. In Ossetia, as far as I know, there are three species of Geotrupes proper.
Of these, G. mutator (Marscham, 1802) clearly differs in the presence of 9 longitudinal grooves from the midline of the elytra to the shoulder protrusion, while the other two species have 7 (or sometimes 6) of them. On the outer side of the male forelegs, the first two teeth are much larger than the subsequent ones and are separated by a clearly distinguishable diastema occupied by the crest-like outgrowth of the base of the second tooth (in females it may be much less pronounced). The subsequent teeth are directed sideways, approximately the same in shape and decrease in size from the 3rd to the next. It is a relatively rare thermophilic species that occurs in different biotopes, but rarely goes high into the mountains.
The remaining 2 species differ in the location of the front legs. Color and size are not significantly different. In Geotrupes spiniger (Marscham, 1802), the third prong on the outer side of the male forelegs is usually quite large and is directed downwards rather than to the side (you need to look and photograph from the side or from below; when viewed from above, it is not always clear where the top of the prong is looking, since its base is usually curved). In females and small males, as well as older specimens with erased teeth, this may be much less pronounced and sometimes difficult to determine, but still the top of the tooth is directed downward. The species is mostly steppe, although it rises in the steppe foothills.
In G. olgae (Olsoufieff, 1918), which is morphologically quite similar to G. stercorarius (of which it is sometimes still considered a subspecies), the third prong on the outer side of the male forelegs is larger than the subsequent ones, but it is directed laterally, not downwards. The latter species is the most mountainous and is usually found in the mountains at a considerable height, including in the alpika.
In your photos, it seems that the first and third are male and female G. olgae; the second may be G. mutator, but count the grooves on the elytra. In view of the above, look at the images of these species on the web, but some of them are incorrectly defined there.

Thank you looked really all Olga at the same time and then rechecked

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14.05.2016 22:40, AGG

Southern Urals, 12.05.2016

1-it is a pity that the first picture does not sufficiently reflect some features of the structure

of the second-it is not informative in this group

, the genitals

are poorly viewed the meaning is that such an animal must be disassembled into s/h and then it is not a fact that it will be possible to accurately determine

something like this. perhaps there are specialists who will determine at least the genus afton/longitarsus / from the photo.... or maybe even xxx. such people should be "caught-and-torn"!!! and still attribute the plants on which they were collected / marked
2-open "green" on the page with the genus Hister, count the whole grooves..... http: / / www. zin. ru / Animalia/Coleoptera/pdf/Part_vol2pp94-111. pdf

This post was edited by AGG - 05/14/2016 23: 10

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