November 27, 2021

List of mimicry between pleasing fungus beetles (Erotylidae) and other kind of beetles/animals.

This journal post will be updated with beetle species showing signs of mimicry with (or by?) erotylid fungus beetle. I was going to make a project for that, but I think a journal post where I can list them and put a side-by-side image of each example will be better.

The type of mimicry erotylids show is the one called Müllerian, where both species share the same warning signs (aposematic) and they share genuine anti-predation mechanisms (in this case, not being palatable for birds, lizards, etc).

However there are very few studies regarding these defense mechanisms for all the species, so maybe some of them are just showing the warning signs, which would configure a Batesian type of mimicry.

Feel free to point out any mimicry that isn't on the list yet and to discuss them. The images shown here are taken from observations in iNat and sometimes from other sources. If you found your image here and you don't want it to be shown, just message me so I can replace it.




Oligocorynus zebraOligocorynus jansoniStenochiinae sp.
Distribution: Central America


Erotylus histrioPoecilopeplus coralliferMelanophryniscus admirabilis
Distribution: Southeast/South Brazil
Remarks: Not only these 2 beetles share the same pattern of alert for predators, but also this nearly extinct small frog. Its underside colors also follow this pattern and it is known that, when threatened, the frog flips belly up (its upper side colors are green-ish).
Related:
Some species from Erotylus histrio group (E. histrionicus, E. elegans, E. chevrolati, E. aegrotus, E. clarosignatus, E. permutatus).
Two species from Poecilopeplus genus (P. corallifer and P. batesi)
Some frogs from Melanophryniscus genus (notably this one from Rio Grande do Sul state, but other species seem to have a similar defense mechanim).


Iphiclus trifasciatusPoecilesthus geniculatus
Distribution: South/Southeast Brazil
Remarks: Many other species of Poecilesthus can be added to this comparison.


Erotylus sp.Eugenysa colossa
Distribution: Peru
Remarks: There's at least 3 or 4 described species of Erotylus that could be tortoise beetles mimics.


Platyphora olalaErotylus sp.
Distribution: Peru
Remarks: There's several described species of Erotylus with variations of this pattern of 4-5 red/yellow bands.


Aegithus quadrinotatusSeladia augustiniana
Distribution: Central America
Remarks: -

Megischyrus brasiliensisPoecilesthus sp.Cymathotes sp.
Distribution: S/SE Brazil
Remarks: I can attest the tenebrionid of this case excreted a bad smell when handling


Iphiclus (Saccomorphus) bilineatusPoecilaspidella vittifera
Distribution: Uruguay, South of South America
Remarks: -

...More to be added soon...



Some literature:
01 - The distribution and evolution of exocrine compoundglands in Erotylinae (Insecta: Coleoptera: Erotylidae 2013 https://www.researchgate.net/publication/271932635
Posted on November 27, 2021 23:06 by fmiudo fmiudo | 0 comments | Leave a comment

September 30, 2021

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 https://www.biodiversitylibrary.org/page/47586660
Perty original description https://www.biodiversitylibrary.org/page/4758a6503
Lacordaire plate https://www.biodiversitylibrary.org/page/42570161
Lacordaire description https://www.biodiversitylibrary.org/page/11545287
Crotch description https://www.biodiversitylibrary.org/page/9797149
Kuhnt description https://www.biodiversitylibrary.org/page/33769526
Erotylina study (source of beetle drawer image) https://doi.org/10.1590/0001-3765202120201452

Posted on September 30, 2021 23:39 by fmiudo fmiudo | 0 comments | Leave a comment

September 09, 2021

Erotylus. Histrio group

This post is a summary of the differences the species of Erotylus from histrio group present.

Introduction

Erotylus is a genus of Erotylidae pleasing fungus beetles with around 100 described species. In 1907-08 Paul Kuhnt divided them in groups according to some characteristics. This post is about the first group, The histrio-group, which his words are "Large species with squat-like, blunt elevation somewhat behind the middle of the elytra; Elytra more or less pointed towards the back. Usually a red spot on the shoulder and a point on the tip, as well as a round yellow spot next to the scutellum (often connected to each other)."

There are 8 species in this group:

Erotylus histrio, E. mirabilis, E. elegans, E. histrionicus, E. chevrolati, E. aegrotus, E. clarosignatus and E. permutatus

Kuhnt created a key with the main differences to which I adapt and illustrate below:

A. Area around the scutellum remains black; 6 yellow bands running from the edge up to the hump

…………………………. E. mirabilis.


B. One yellow spot next to the scutellum (sometimes combined with the yellow bands/spots behind)

Posted on September 09, 2021 01:33 by fmiudo fmiudo | 1 comment | Leave a comment

March 19, 2021

Jacintho Guérin 1956 Erotylidae Plates

The 2 pages showing the drawings of the article copy I purchased from the Australian National Library.

  1. Strongylosomus simplex
  2. Aegithus cretaceus
  3. Iphiclus (Habrodactylus) discrepans
  4. Iphiclus (Habrodactylus) hamatus
  5. Iphiclus (Habrodactylus) septemmaculatus
  6. Iphiclus (Brachymerus) neglectus
  7. Iphiclus (Saccomorphus) humeralis
  8. Iphiclus (Iphiclus) striolatus
  9. Iphiclus (Iphiclus) quadristictus
  10. Iphiclus (Neobarytopus) alboniger
  11. Iphiclus (Neobarytopus) divisus
  12. Iphiclus (Neobarytopus) iris
  13. Iphiclus (Neobarytopus) lunaris
  14. Iphiclus (Neobarytopus) jacinthoi
  15. Iphiclus (Neobarytopus) rhomboidalis
  16. Iphiclus (Neobarytopus) tigrinatus
  17. Iphiclus (Neobarytopus) pauper
  18. Iphiclus (Neobarytopus) octopustulatus
  19. Iphiclus (Megaprotus) obliteratus
  20. Erotylus superbus
  21. Erotylus oblitus
  22. Erotylus longulus
  23. Neopriotelus quadrimaculatus
  24. Ischyrus natalensis
  25. Mycotretus anchoralis
  26. Mycotretus trifasciatus
  27. Mycolybas rufipennis

1956 Guérin, Jacintho. Descrição de novas espécies e variedades de Erotylidae (Col.) neotropicais. Dusenia, Curitiba v7 fasc. 1: 65-66

Posted on March 19, 2021 16:17 by fmiudo fmiudo | 2 comments | Leave a comment

December 05, 2020

Rearing Euglyphis cf. elena (Lasiocampidae) larva to moth.

One month after encountering this beautiful caterpillar in my garden I found it again eating this plant I knew was abundant around, so I decided to try grow it into whatever moth/butterfly it would become.

At the time I wasn't even sure of its Family or even the plant ID, but later I discovered it could be something that iNat still doesn't have. I kept the larva inside an old CD box that was big enough for it to move around and select which leaf to eat. I offered it several types of leaves from different plants during the course of the larval stage, but it always favored the initial plant where I found it (Ocotea puberula - Lauraceae).

From the day of capture till the day it started weaving its pupa 16 days passed. I had no idea what would it do to make the pupa, so I've offered it some twigs and tree bark from the plant it used to eat as a support surface. Turns out it actually made the pupa inside one of the leaves; bending it and "gluing" the edges with silk.

Video of the larva preparing its leaf/silk pupa https://youtu.be/vGaEIPqpPGg

It took 4 days for it to enclose itself in the pupa and 18 more days for the adult to emerge. Here's the timeline:

  • 28th Sept. 2020 - First time encountering the species
  • 27th Oct. 2020 - Second time encountering the species and collecting larva
  • 12th Nov. 2020 - Pre-pupa stage
  • 16th Nov. 2020 - Pupa stage
  • 04th Dec. 2020 - Adult emerges

Study to determine the species

According to SPECHT, CORSEUIL & FORMENTINI - 2005 there's a total of 52 species of Lasiocampidae occuring in my state (Rio Grande do Sul - Brazil):

Since I managed to narrow down to the Genus Euglyphis we are down to :

Euglyphis brunnea (Schaus, 1894) = adult pic on BOLD
Euglyphis castrensis (Schaus, 1894) = No information about it
Euglyphis claudia claudia (Stoll, 1782) = Adult pic on iNat
Euglyphis deusta (Herrich-Schäffer, 1854) = larva pic on iNat
Euglyphis efferata Draudt, 1927 = No information about it
Euglyphis fibra (Schaus, 1890) = larva pic
Euglyphis guttivena (Walker, 1855) = larva pic
Euglyphis guttularis (Walker, 1855) = Adult pic on iNat
Euglyphis lacrimosa (Schaus, 1892) = Schaus description mention white lines on primaries
Euglyphis lascoria cariacica Draudt, 1927 = Main suspect
Euglyphis lignosa (Walker, 1855) = larva pic on iNat
Euglyphis marna (Schaus, 1896) = adult pic on iNat
Euglyphis melancholica (Butler, 1878) = adult pic on iNat
Euglyphis narceta (Schaus, 1905) = Schaus description mention white spot on costa
Euglyphis nigropunctata (Schaus, 1905) = possible
Euglyphis plana (Walker, 1855) = adult pic on BOLD
Euglyphis rearensis Schaus, 1936 = couldn't find description
Euglyphis salebrosa Draudt, 1927 = couldn't find description
Euglyphis semifunebris (Schaus, 1915) = adult drawing
Euglyphis sulga (Schaus, 1905) = possible
Euglyphis terranea (Butler, 1878) = adult pic on BOLD
Euglyphis zikani Draudt, 1927 = adult pic on BOLD

Update! 14/12/2020 Looks like this could be Euglyphis elena. Check adult observation for more info.

Posted on December 05, 2020 23:53 by fmiudo fmiudo | 4 observations | 1 comment | Leave a comment

Archives

Gracias al apoyo de:

¿Quiere apoyarnos? Pregúntenos cómo escribiendo a snib.guatemala@gmail.com