Hemiptera

True bugs, hoppers, aphids, whiteflies, & scale insects. Largest order of Exopterygota. Fossil record from Lower Permian to Recent. Predominantly plant feeding insects, some predaceous or parasitic.

Bichos Argentinos #9 – Membracido

/ Ted C. MacRae / 3 Comments

Enchenopa? sp. | Buenos Aires, Argentina

This treehopper that I photographed at La Reserva Ecológica Costanera Sur strongly resembles our North American species of Campylenchia due to the brown elytra and lack of any yellow markings on the pronotal crest.  However, the rounded lower margin of the frons (more apparent in the full-sized version of this photo) eliminates this genus as a possibility and suggests instead the closely related Enchenopa. 

I sent this and another photo to Andy Hamilton (Canadian National Collection of Insects, Arachnids and Nematodes) for his opinion.  Andy claims to be a hack when it comes to Neotropical Membracidae (focusing more on world Cercopidae and Holarctic Cicadellidae), but he is a much better hack than I!  In his reply, he mentions that a lot of work is still needed on tropical species and genera, and in fact none of our North American species of Enchenopa actually resemble the type-species from Brazil (Membracis monoceros).  Most of what we now consider Enchenopa will likely be referable back to the genus Membracis (type genus of the family), but where the species in the above photo will eventually fall remains anyone’s guess.

Copyright © Ted C. MacRae 2011

Bichos Argentinos #5 – Cyrtocoris egeris

/ Ted C. MacRae / 14 Comments

Cyrtocoris egeris | 15 km S Reconquista, Pcia. Santa Fe, Argentina

Despite its obvious membership in the order Hemiptera, I knew the insect featured in ID Challenge #7 would be a difficult subject to identify.  This bizarre bug is Cyrtocoris egeris, a member of the small pentatmoid family Cytocoridae (congratulations to HBG Dave, who was the only commenter to correctly identify not only the family, but the genus).  While their relationship to Pentatomidae (stink bugs) and Scutellaridae (shield-backed bugs) is obvious, hemipterist-great Carl Schaefer thinks these insects might actually be most closely related to the Cydnidae (burrowing bugs).  I encountered this individual a couple of weeks ago in a soybean field in Santa Fe Province, Argentina.  Now, I have to be honest here – I did not figure this one out on my own. Instead, I assumed it must be some bizarre member of the Pentatomidae or Scutellaridae, and it was only after my repeated searches in either of those two families failed to turn up anything promising did I throw up my hands and call for hired help. This time it was USDA Research Entomologist Don Thomas, a pentatomid specialist (and former co-alumnus at the University of Missouri) who responded to my query with a genus-level ID. Once I had that bit of information in hand I was able to locate the recent revision of the family (Packhauskas and Schaefer 1998) and identify the species.

Looks stink bugish enough in this head on view...

In addition to the expanded scutellum bearing a broad-based spine or hump, members of this exclusively Neotropical family are characterized by flattened expansions of the anterior part of the head, the covering of flattened scalelike setae, and a mediodistal tubercle on at least the foretibiae. Packauskas and Schaefer (1998) recognize only three genera and 11 species in the family, its members occurring from Argentina north through central Mexico.

...but there's some crazy stuff going on at the back end.

My ID as C. egeris is based on the very well-developed scutellar crest and my interpretation of the humeral projections not extending forward of the anterior angles next to the head. Packauskas and Schaefer (1998) recorded this wide-ranging species from Mexico to Argentina, with the southernmost specimens in extreme northeastern Argentina (Pcia. Missiones), but Schaefer et al. (2005) later recorded it from Reconquista – also on soybean. Cyrtocoris gibber is very similar to C. egeris and is also widespread from Costa Rica to Argentina (and also with the southernmost record in Pcia. Missiones, Argentina), but in that species the humeral expansions project forward nearly as far as the anterior angles of pronotum (strongly surpassing a line drawn through the bases of these angles).  Besides soybean for C. egeris, the only other host records I am aware of for any species in the family are by Costa Lima (1940), who reported C. gibbus on the branches of Mimosa scabrella (Leguminosae), and Schaeffer et al. (2005), who reported C. tigrinus on Sida rhombifolia (Malvaceae) (although nymphs could not be reared to adulthood on this plant).

REFERENCES:

Costa Lima, A. 1940. Insetos do Brasil. 2° Tomo, Capitulo XXII. Hemipteros. Escola Nacional do Agronomia, Rio de Janeiro.

Packauskas, R. J. and C. W. Schaefer. 1998.  Revision of the Cyrtocoridae (Hemiptera: Pentatomoidea).  Annals of the Entomological Society of America 91(4):363–386;

Schaefer, C. W., A. R. Panizzi and M. C. Coscarón. 2005.  New records of plants fed upon by the uncommon heteropterans Cyrtocoris egeris Packauskas & Schaefer and C. trigonus (Germar) (Hemiptera: Cyrtocoridae) in South America.  Neotropical Entomology 34(1):127-129.



Brazil Bugs #16 – Outro Percevejo

/ Ted C. MacRae / 6 Comments

Proxys sp. | Barão Geraldo, Campinas, Brazil

Another stink bug (family Pentatomidae) from my recent travels to South America, but this one from southeastern Brazil rather than Argentina.  Although the white spot at the apex of the scutellum is a common theme across the family, the jet black coloration and strongly acute clypeus (“nose”) immediately reminded me of Proxys punctulatus from eastern North America. Although that species does also occur south through Mexico and Central America into northern South America, the lack of distinctively black femoral apices (“knees”) on this individual suggest it is likely a different species.  I’ve not found much information on other species in this genus, as my old standby Flickr repeatedly proffers images of P. punctulatus in its Pentatomidae pages but not other species in the genus.  Grazla and Campos (2010) list P. hastator from “Cayenna” (likely French Guiana) and P. victor from “Brésil,” and an illustration of the latter in the monumental Biologia Centrali-Americana (Distant 1880-1893) agrees reasonably well (but not completely) with this individual.  For now, this will have to stand as Proxys sp.

REFERENCES:

Distant, W. L.  1880-1893.  Biologica Centrali-Americana. Insecta. Rhynchota. Hemiptera-Heteroptera. Volume I.  London: published for the editors by R. H. Porter, 462 pp.

Grazia, J. and L. A. Campos. 2010. Neotropical Pentatomidae (Insecta: Hemiptera: Heteroptera) of the collection of Massimiliano Spinola preserved in the “Museo Regionale de Scienze Naturali”, Turin, Italy. ZOOLOGIA 27(3):413–424.

Copyright © Ted C. MacRae 2011

Bichos Argentinos #4 – Balancing Act

/ Ted C. MacRae / 4 Comments

Nezara viridula (southern green stink bug) | Pergamino, Pcia. Buenos Aires, Argentina

I encountered this adult Nezara viridula (southern green stink bug) (Hemiptera: Pentatomidae) in a soybean field in Buenos Aires Province, Argentina.  I liked the way it balanced itself on the leaf on which it was sitting to keep its body level.

Copyright © Ted C. MacRae 2011

Brazil Bugs #15 – Formiga-membracídeos mutualismo

/ Ted C. MacRae / 50 Comments

Of the several insect groups that I most wanted to see and photograph during my trip to Brazil a few weeks ago, treehoppers were near the top of the list.  To say that treehoppers are diverse in the Neotropics is certainly an understatement – South America boasts an extraordinary number of bizarre and beautiful forms that still, to this day, leave evolutionary biologists scratching their heads.  The development of this amazing diversity is a relatively recent phenomenon (thinking geological scale here), as there are no known membracid fossils prior to Oligo-Miocene Dominican and Mexican amber – well after the early Cretaceous breakup of Gondwanaland split the globe into the “Old” and “New” Worlds.  With its origins apparently in South America, numerous groups continued to spring forth – each with more ridiculous pronotal modifications than the last and giving rise to the dazzling diversity of forms we see today.  Even North America got in the evolutionary act, benefiting from northern dispersal from South America’s richly developing fauna via temporary land bridges or island stepping stones that have existed at various times during the current era and giving rise to the almost exclusively Nearctic tribe Smiliini (whose species are largely associated with the continent’s eastern hardwood forests).  Only the subfamily Centrotinae, with its relatively unadorned pronotum, managed to successfully disperse to the Old World, where it remains the sole representative taxon in that hemisphere.  With a few notable exceptions, treehoppers have virtually no economic importance whatsoever, yet they enjoy relatively active study by taxonomists, evolutionists, and ecologists alike – due almost completely to the bizarreness of their forms and unique mutualistic/subsocial behaviors.

I did manage to find a few species of treehoppers during the trip (a very primitive species being featured in Answer to ID Challenge #4 – Aetalion reticulatum), and of those that I did find the nymphs in this ant-tended aggregation on a small tree in the rural outskirts of Campinas (São Paulo State) were perhaps the most striking in coloration and form.  Most were jet black, although a few exhibited fair amounts of reddish coloration, and all exhibited sharply defined white bands of wax and long erect processes on the pronotum, mesonotum, and abdomen.  I’ve seen a fair number of treehopper nymphs, but I did not recognize these as something I had seen before, and given the incomplete state of immature taxomony I feared an identification might not be possible.  Still (and I know this is probably beginning to sound like a broken record), I gave it the old college try.

I usually like to start simple and get more creative if the results aren’t satisfactory, so I went to my old friend Flickr and simply typed “Membracidae” as my search term.  Predictably, pages and pages of results appeared, and I began scanning through them to see if any contained nymphs at all resembling what I had.  After just a few pages, I encountered this photo with very similar-looking nymphs, and although no identification beyond family was indicated for the photo, I recognized the lone adult sitting with the nymphs as a member of the tribe Aconophorini – a diverse group distinguished from other treehoppers by their long, forward-projecting pronotal horn.  Luck was with me, because I happen to have a copy of the relatively recent revision of this tribe by Dietrich and Deitz (1991).  Scanning through the work, I learned that the tribe is comprised of 51 species assigned to three genera: Guayaquila (22 spp.), Calloconophora (16 spp.), and Aconophora (13 spp.).  The latter two genera can immediately be dismissed, as ant-interactions have not been recorded for any of the species in those two genera – clearly the individuals that I photographed were being tended by ants.  Further, the long, laterally directed apical processes of the pronotal horn, two pairs of abdominal spines, and other features also agree with the characters given for nymphs of the genus Guayaquila.  In looking at the species included in the genus, a drawing of a nymph that looked strikingly similar to mine was found in the species treatment for G. gracilicornis.  While that species is recorded only from Central America and northern South America, it was noted that nymphs of this species closely resemble those of the much more widely distributed G. xiphias, differing by their generally paler coloration.  My individuals are anything but pale, and reading through the description of the late-instar nymph of the latter species found every character in agreement.  A quick search of the species in Google Images was all that was needed to confirm the ID (at least to my satisfaction). 

In a study of aggregations of G. xiphias on the shrub Didymopanax vinosum (Araliaceae) in southeastern Brazil, Del-Claro and Oliveira (1999) found an astounding 21 species of associated ant species – a far greater diversity than that reported for any other ant-treehopper system.  The most frequently encountered ant species were Ectatomma edentatum, Camponotus rufipes, C. crassus, and C. renggeri, and after perusing the images of these four species at AntWeb I’m inclined to believe that the ants in these photos represent Camponotus crassus (although I am less confident of this ID than the treehoppers – corrections welcome!).  The authors noted turnover of ant species throughout the day in a significant portion of the treehopper aggregations that they observed, which they suggest probably reflects distinct humidity and temperature tolerances among the different ant species and that might serve to reduce interspecific competition among ants at treehopper aggregations.  Since treehopper predation and parasitism in the absence of ant mutualists can be severe, the development of multispecies associations by G. xiphias results in nearly “round-the-clock” protection that can greatly enhance their survival.

Update 3/3/11, 9:45 a.m.:  My thanks to Chris Dietrich at the Illinois Natural History Survey, who provided me in an email exchange some clarifying comments on the origins and subsequent dispersal of the family.  The first paragraph has been slightly modified to reflect those comments.

REFERENCES:

Del-Claro, K. and P. S. Oliveira. 1999. Ant-Homoptera interactions in a Neotropicai savanna: The honeydew-producing treehopper, Guayaquila xiphias (Membracidae), and its associated ant fauna on Didymopanax vinosum (Araliaceae). Biotropica 31(1):135–144.

Dietrich, C. H. and L. L. Deitz.  1991.  Revision of the Neotropical treehopper tribe Aconophorini (Homoptera: Membracidae).  North Carolina Agricultural Research Service Technical Bulletin 293, 134 pp.

Copyright © Ted C. MacRae 2011

Answer to ID Challenge #4 – Aetalion reticulatum

/ Ted C. MacRae / 8 Comments

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

Brazil Bugs #7 – Cigarrinhas

/ Ted C. MacRae / 2 Comments

It seems that North American entomologists have returned en masse from their various tropical winter travels – Alex and Brigette have returned from their respective trips to Ecuador, Troy has come back from Costa Rica, and I am now back home after my recent business trip to São Paulo, Brazil.  I’m anxious to see the photos and read the tales that the others will no doubt be posting in the coming weeks regarding their visits to cloud forests, research stations, and nature preserves.  My insect hunting activities were limited to municipal parks and hotel grounds, but I still have a decent variety of insect encounters to share (along with many pleasant memories of churrasco, cerveja, e novos amigos).

Acrogonia citrina

Thanks to Ani, I think we now agree that the pink-flowered shrub on the grounds of my hotel in Campinas that attracted such a nice diversity of insects belongs to the genus Ixora (family Rubiaceae).  Included in this post are a few leafhoppers (order Hemiptera, family Cicadellidae) in a group known as ‘sharpshooters’ (subfamily Cicadellinae) that I found also attracted to this shrub.  Leafhoppers are, of course, a hugely diverse family, but because of the generally small size and cryptic coloration of most North American species, it is a group that often goes unnoticed.  In the tropics, however, it’s a different story, with not only a number of larger forms but also a multitude of brightly colored species.

Acrogonia citrina at 5X life size

The diversity of species present in a place like southern Brazil might seem to preclude any possibility of identification without consulting a specialist, but the individual in these first two photos looks very much like Acrogonia citrina.  This species has become a major pest of citrus in São Paulo state during the past two decades, its importance driven not so much by direct damage, but rather by vectoring a bacterial disease of citrus called Citrus Variegated Chlorosis (Xylella fastidiosa) – or CVC (Lopes 2007).  Of the 12 sharpshooter species identified as vectors of CVC, A. citrina is among the most important due to its abundance in citrus groves (an important agricultural crop in São Paulo state) and high degree of polyphagy.  The disease affects mainly fruit quality, reducing their size and making them unsuitable to be sold fresh, and by decreasing yield when processed for juice.

Dilobopterus costalimai

Dilobopterus costalimai is another important vector of CVC, again primarily as a result of its abundance on citrus in São Paulo state and polyphagous nature.¹  At this point, CVC has not been found outside of South America; however, California and Florida citrus growers are understandably nervous about the potential for its eventual occurrence in the U.S. due to the presence here of leafhopper species that are confirmed vectors of the disease and the ease with which the disease can be transported in infected nursery stock.  There is no cure for CVC, and chemical control of vectors is both costly and difficult, leaving nursery certification, protection of nursery stock from infection, pruning of symptomatic parts of trees to remove inoculum sources, and other such labor intensive methods as the only options for managing CVC (Chung and Brlansky 2009).

¹ I originally attempted to photograph this individual because it appeared to have been parasitized by what I suspect is a dryinid (order Hymenoptera, family Dryinidae).  Unfortunately the parasitoid is on the right side of the abdomen of this individual and can’t really be seen in this view, and I didn’t get any other shots besides this one.

REFERENCE:

Chung, K.-R. and R. H. Brlansky.  2009.  Citrus Diseases Exotic to Florida: Citrus Variegated Chlorosis (CVC).  University of Florida, Institute of Food and Agricultural Sciences Fact Sheet PP-223, 4 pp.

Lopes, J. S.  2007.  Vector ecology and implications on epidemiology of citrus variegated chlorosis.  Proceedings of the 2007 Pierce’s Disease Research Symposium, California Department of Food and Agriculture.

Copyright © Ted C. MacRae 2011

Brazil Bugs #4 – Mais dos percevejos

/ Ted C. MacRae / 24 Comments

I found mais dos percevejos (more of the leaf-footed bugs) on the still-unnamed pink flowering shrub in back of the hotel in Campinas, Brazil.  Not only am I convinced that they truly do belong to the family Coreidae (for the reasons mentioned in the earlier post and below), but also that despite the different color patterns shown by the two individuals in that post that they are indeed a single species.  I also found the above individual, representing an even more heavily melanized version than the two shown previously.  In looking at a large number of individuals on the shrubs (and subsequently encountering them in a different part of Campinas over the weekend), it became clear that there were not just two distinct color forms but a broad range of variability.  I could believe maybe two species occurring together on a common resource, but it seems unlikely that each color variation represents a different species.  Thus, it now seems that there is one highly variable species visiting these flowers.

I had an idea on how to find the name of this species that almost worked.  Rather than Googling “leaf-footed bug” or “Coreidae,” I tried “percevejo” instead, along with Brazil or Brasil.  There were 3 or 4 photographs that showed up in the images search that I recognized instantly as belonging to the same species.  Unfortunately, none of the links where the photos were found gave any information more specific than family (all, however, agreeing with family Coreidae).  I think it’s time to send an email to Harry Brailovsky, a coreid specialist at the Instituto de Biologia (UNAM) in Mexico City.

Photo 1: Canon MP-E 65mm 1-5X macro lens (ISO 100, 1/200 sec, f/13).
Photo 2: Canon 100mm macro lens (ISO 100, 1/200 sec, f/16).
Both photos: Canon 50D, Canon MT-24EX flash w/ oversized DIY concave diffuser. Typical post-processing (levels, color, unsharp mask).

Last minute edit: I just heard back from Harry Brailovsky as I was ready to post (thank you Harry!).  The insect is, indeed, a species of Coreidae, which he identified as a member of the genus Hypselonotus.  I did some searching online to see if I could find any additional clues as the species identity – I found no images that looked right but did find this key to the Hypselonotus of Costa Rica.  The key relies on some ventral characters, and I’m a little uneasy about using it for something from southern Brazil, so I think I’ll just wait until Harry has a chance to look it up when he returns to the museum.

Second update 1/26/11:  Harry has confirmed the species as Hypselonotus interruptus, which was mentioned but not included in the key that I linked to above.  The only online images I have found of this species are at this link. Either Harry is wrong (unlikely), the photos in the link are misidentified (maybe), or the species is enormously variable (perhaps quite likely).

Copyright © Ted C. MacRae 2011