Erotylus incomparabilis fixing needed.

By the time I'm writing this post, there is about 50 observations of pleasing fungus beetles of the genus Erotylus identified as Erotylus incomparabilis (Perty, 1832) here on iNaturalist. In my opinion they are incorrectly identified and we should try to fix that. Several other places in the internet are also incorrect.

I'm making this post so that I can use it as reference for when I'm fixing the IDs on those observations in the following days, but first let me explain what E. incomparabilis is.

The species was firstly described in 1832 in the work Delectus animalium articulatorum : quae in itinere per Brasiliam by the illustrator and contributor Maximilian Perty. His diagnosis in short Latin was:

"ovalis, gibbus, niger, elytris coccineis, ad basin, nigris, flavopunctatis, postice nigro undidatis. - Long. 8 mm. - Amazon River.

Which we can translate to "Oval, convex, black, elytra red but black at the base, with yellow punctures and with black waves at the apical part."

Later Lacordaire didn't bring more details, but both Perty and Lacordaire brought drawings for the species.

Perty's drawing of E. incomparabilis (Figure 8)

Lacordaire's drawing of E. incomparabilis (Figure 4)

Crotch was the first to tell us that this was the most variable species of the genus. Kuhnt exemplified some other variants. Kuhnt also made a deep study about this genus and divided the species in several groups. Erotylus incomparabilis was put inside the group #5; The Varians Group, which characteristic is "by combining narrow bands, wide bands are created; at most 3 bands are available." This group had 14 species (counting E. incomparabilis) at the time.

A recent work about another genus Erotylina brought a very interesting image of a beetle drawer that gathered several, if not all, of the variations.

A collection of pinned specimens of Erotylus showing several instances of E. incomparabilis.

So based on these evidences and descriptions we are better raising the ID of those observations to the genus level Erotylus at least, since, unfortunately this genus has several species with very subtle differences between them, so we might not be able to replace a species for another in this case. The last thorough study on those beetles is 100+ years old... Hopefully new studies such as the recent one about Erotylina leoparda can shed some light on Erotylus too, and we might find several synonyms.

Perty plate
Perty original description
Lacordaire plate
Lacordaire description
Crotch description
Kuhnt description
Erotylina study (source of beetle drawer image)

הועלה ב-ספטמבר 30, 2021 11:39 אחה"צ על ידי fmiudo fmiudo


לא קיימות הערות בינתיים

הוספת תגובה

כניסה או הרשמה להוספת הערות