Answer to ID Challenge #4 – Aetalion reticulatum

Aetalion reticulatum female guarding her egg mass - São Paulo state, Brazil.

ID Challenge #4 seems to have been a little more difficult than I anticipated – only a few people mustered the courage to even hazard a guess, of whom TGIQ emerged with maximum points to take the win.  Looking sort of like a cross between a leafhopper (family Cicadellidae) and a treehopper (family Membracidae), Aetalion reticulatum is one of a few species and the only genus comprising the family Aetalionidae.  While lacking the pronotal processes that characterize species in the much more diverse and better known Membracidae, aetalionids are nevertheless considered treehoppers as well, along with another little-known family Melizoderidae.  As a whole, the Aetalionidae + Melizoderidae + Membracidae form a sister group to the Cicadellidae (Deitz and Dietrich 1993), which combine to form the most diverse and successful lineage of sap-sucking phytophagous insects. 

Like many treehoppers, A. reticulatum exhibits ant-mutualistic and presocial behaviors; however, it remains unclear whether these behaviors were acquired separately by each treehopper lineage or if they represent retention of a more primitive condition (sorry, Alex – it’s just easier to say it that way than deal with terms such as ‘retained plesiomorphy’ and ‘phylogenetic conservatism’).  Aetalion reticulatum occurs broadly in the New World tropics, where females can often be found perched on top of their egg masses.  Some (but not all) guarding females make periodic sweeps of the hing legs down the sides of the egg mass, apparently to dislodge egg parasitoids and discourage further attack (Preston-Mafham & Preston-Mafham 1993).  Ant-mutualistic relationships and the tendency to form colonies provide additional protection from predators.

Now is a good opportunity to summarize the ‘1st BitB Challenge Series’ overall standings – Ben Coulter maintains his overall lead by gaining points in every challenge.  TGIQ climbs into 2nd place with this week’s win, and tceisele leap frogs over several contestants to tie Janet Creamer for the 3rd podium spot (and gets the nod for more frequent participation).  It’s no real surprise that the most frequent players took the top spots.  At this point, I’m going to call a close to the 1st series and declare Ben Coulter the overall series winner – contact me for your loot!  To the rest, thanks for playing, and now that you know how this game works maybe you’ll think about making a move for the 2nd series win!

Place Commenter IDC #1 SSC #3 IDC #2 IDC #3 IDC #4 Total
1 Ben Coulter 9 14 9 4 4 40
2 TGIQ 8 5 10 23
3 tceisele 3 8 3 14
4 Janet Creamer 14 14
5 James Trager  6 5 11
6 Dave 11 11
7 Christopher Taylor 7 3 10
8 Dave Hubble 6 2 8
  JasonC 5 3 8
10 Charley Eiseman 7 7
  Delbert La Rue 7 7
  jason 7 7
  Techuser 7 7
14 Richard Waldrep  6 6
15 Alex/Watcher 2 2
  dragonflywoman 2 2
  nellie 2 2
16 Brady Richards  1 1
  Francis 1 1
  macroinstantes 1 1
  Margarethe 1 1
  Mark Deering  1 1
  Andrew 1 1

REFERENCES:

Deitz, L. L. and C. H. Dietrich.  1993.  Superfamily Membracoidea (Homoptera: Auchenorrhyncha). I. Introduction and revised classification with new family-group taxa.  Systematic Entomology 18(4):287–296.

Preston-Mafham, R. and K. Preston-Mafham.  1993.  The Encyclopedia of Land Invertebrate Behaviour.  The MIT Press, 320 pp.

Copyright © Ted C. MacRae 2011

8 thoughts on “Answer to ID Challenge #4 – Aetalion reticulatum

  1. Woohoo! I’m thrilled that I got 2 points! I rarely have any clue what the insect in the photo is (i.e. they’re not aquatic) and I’m never going to be a competitor in these contests, so I am quite pleased I made it onto the list at all. 🙂

    • Never say never! 🙂

      This last series shows that consistency of participation is as big a factor in determining the final winner as drilling down to species-level IDs. To make things fair, however, I should probably try to include a few more aquatics in future challenges.

      • Yes, I was surprised to see that I’d moved up to tie for 3rd place, even though my maximum score on any one challenge was only 8 points. And my insect knowledge is still pretty much at the layman level.

        And, Ted, I’d like to thank you for not making these a first-past-the-post challenge. I really appreciate being able to participate even if I don’t happen to check the page within a couple of minutes of it being posted.

        • Hi Tim. I gave a lot of thought to how to structure these challenges to eliminate some of the problems as I saw them of previous challenges. Moderating comments eliminates the advantage given to those who, by accident or design, get to the post first. It also solves the “winner takes all” conundrum that makes it difficult to accumulate points unless you actually win the challenge. Your accumulating enough points to make the overall podium was a result of decent knowledge combined with consistent participation.

          It would be too much work, but I’d be interested to go back and see how the overalls would look if I only awarded points on a first-to-post basis.

  2. Pingback: ID Challenge #10 « Beetles In The Bush

  3. Pingback: Aetalionid : Nature Closeups

  4. Hi Ted. I just checked with Deitz and Dietrich publication and they mention that Aetalionidae includes :

    Family Actalionidae Spinola, 1850
    Subfamily Aetalioninae Spinola, 1850
    Tribe Aetalionini Spinola, 1850 (including only Aetalion Latreille, 1810)
    Tribe Darthulini Metcalf, 1939 (including only Darthula Kirkaldy. 1900)
    Subfamily Biturritiinae Metcalf, 1929 (including Biturritia Goding, 1930, Gerridius Fowler, 1896, Lophvraspis Stil. 1869, Mina Walker, 1858, and Tropidaspis Stbl, 1869)

    So, it seems that there is more than one genus in Aetalionidae.

    Saludos.

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