Armchair biodiversity discovery during COVID

With the COVID-19 pandemic, many of us are working at home, instead of in the field. In spite of this, I think that I have made a taxonomic discovery that is important for phorid classification.

My friend, Lonny Coote, recently wrote to me, saying he would help me with some entomological questions if I “describe[d] a second species of Cootiphora”, a genus I described and named for him in 1993. Since then, the genus Cootiphora has languished in obscurity. I have seen only three specimens: the holotype from Tinalandia, Ecuador, a second specimen from La Selva Biological Station, Costa Rica, and a third specimen from Bastrop State Park, Texas (near Austin).

The genus Cootiphora is known only from these three female specimens. They are extremely distinctive because of their cockroach-like, limuloid body form, their reduced, triangular wing rudiment, and their pointed, parasitoid-type oviscape.

The female Cootiphora specimen from Bastrop, TX

The holotype was collected (as the label states) on “the clubhouse windows”. Tinalandia was (is?) a golf course with some nice forest on the property that makes it a popular place with naturalists. It was on my first trip to the tropics, accompanied by Lonny Coote, John Acorn, and Jane O’Donnell, that I visited this resort and received the kind hospitality of Tina herself. One day, army ants (Eciton burchellii) invaded the clubhouse, and the windows were rife with flies associated with the ants. I had a great time collecting numerous phorids on that day, much to the chagrin of Lonny, who saw one of the wasps that he worked on during the first day of that trip, and not a single one thereafter. Amongst those phorids was the little female fly that I later described and named for him. I always assumed that it was associated with the army ants, but of course had no evidence of this.

Coote’s demand that I “describe a second species of Cootiphora” prompted me to look at the specimens I had gathered from Bastrop, Texas, just for fun. In doing so I noticed another peculiarity about the Bastrop fauna- I had described a new species of an unusual tropical genus known only from males from this park. Finding these flies, which I named Macrocerides (Tauricornis) taurocephalus, the name referring to the bull-horn like antennae of the males of all species in this subgenus. In my Macrocerides paper, I described two new species, one tropical (M. (T.) borkenti) and one nearctic (M.(T.) taurocephalus). I had never put this association together in my mind, but it seemed provocative that I would find these two tropical flies, one known only from males, and one only from females, at this site in Texas.

There was one thing left to check: I looked through the prepared, mounted, labelled material from that day in the clubhouse at Tinalandia, and found, to my delight, a single male specimen of M.(T.) borkenti.

Of course, this is still speculation, but if true, I would consider M.(T.) borkenti to be a synonym of Cootiphora angustata (the type species of Cootiphora); at least the subgeneric name Tauricornis to be a synonym of Cootiphora; Macrocerides (Cootiphora) angustata.

But wait, there’s more! Among the material I treated in my Macrocerides review were two further species, M. abaristalis Borgmeier from Costa Rica and M. attophilus Disney from Argentina. Both of these might be further species of Cootiphora, but most interesting is the latter, which was collected in association with leaf-cutter ants. This is significant, because one of the most distinctive things about the Bastrop State Park site back in Austin, Texas, is the large number of Apocephalus wallerae specimens also in the Malaise trap samples. This species is a parasitoid of Atta texana, whose colonies are common in the area (according to Alex Wild of the University of Texas, Austin, who kindly corresponded with me about this). Thus we have another hint of where to look for further Cootiphora specimens- in association with this leaf-cutter ant.

               Finally, I have some serious reservations about the monophyly of genus Macrocerides, discussed in my review of the genus. There is little to link the type species, M. curtifrons Borgmeier, with the species of subgenus Tauricornis, other than the moderately modified antennae. If further research indicates that these species are not closely related to M. curtifrons, we will be free to use Cootiphora as a full genus name again, something that I think would please my friend. At any rate, I think I have fulfilled his request: I speculatively have “found” not one, but two more species of what would be subgenus Cootiphora!

Another insanely good photograph by Steve Marshall, showing phorid sex

A mating pair of Phalacrotophora halictorum

My long-time friend, one-time advisor (for my MSc degree program), and world’s leading Dipterist (as selected in 2018 by the North American Dipterological Society- NADS), Dr. Steve Marshall, has amazed me again with another incredible photograph, this time of a pair of mating Phalacrotophora halictorum in flight (male on the left, female on the right). The interesting thing about this photo, besides the almost impossibility of capturing these little 1-2 mm long flies in flight, is the information about mating that it provides. Look at the precise placement of the male’s front legs and middle legs on specific parts of the female abdomen. This is not a male that is just holding on for dear life as it flops along attached to the female: this male is touching her in very specific parts of her body, presumably as a type of external courtship to convince the female to use his sperm. This photo gives us:

1- Potential phylogenetic information to compare with other, related flies when we observe where they touch their females while in flight.

2- Sites to examine on the bodies for specialized sensory structures. For instance, the female abdomen must have some kind of receptors that allow it to register the touch of the male. Insects don’t have highly sensitive skin like we do, they have an exoskeleton that has specific sensory structures, usually hair-like setae, that allow them to detect touch. Likewise, the male legs probably have some kind of structures that are used to stroke or otherwise stimulate the female. I’ll be looking at specimens in the collection to see if I can find male or female structures that correlate to these points of contac

3- Behavioral details that add to our ever-so-slowly increasing body of knowledge about mating patterns in phorids and other flies (see my previous post on Fly Porn).

I hope you are as impressed with this photo, and with Steve, as I am. He has a number of books featuring his photographs, including the best book ever written on flies. You can’t go wrong buying any of them.

Phorids and other flies from the urban “wilds”

Two papers have appeared recently based on our BioSCAN (Biodiversity Science: City and Nature) project. In this project, we partner with the public by placing Malaise traps (tent-like traps with a collecting bottle on top) in backyards and gardens, obtaining the homeowner’s help and permission to sample in places that would otherwise be off limits. We call our collaborators “site hosts”.

Each of the new papers looks at fly diversity in Los Angeles in slightly different ways, and involves a team of ecologists that are helping us interpret our results.

One of the BioSCAN sites and the Sanchez family, the site hosts

The first was headed by Dr. Terry McGlynn from California State University, Dominguez Hills (the full list of authors and the full citations are given below). Terry and colleagues looked at our weather station data along with phorid diversity from the first phase of BioSCAN (the phorid diversity was described by Brown & Hartop 2015). They found a Goldilocks situation with temperature as the strongest variable: not too hot and not too cold described the optimum conditions for phorid diversity. This makes climate change a real concern, given that even phorids (tough little flies) react strongly to small changes in conditions.

The second paper, headed by former postdoc Dr. Max Adams (now at George Washington University), looked at more groups of insects (including also syrphid and tipulid flies (flower flies and crane flies) and more variables. This paper found that the amount of water that was put on the landscape was most important, and that reducing water (as in dryland gardening) increased insect diversity across habitat types as diverse as parkland and high density residential areas. This might seem counter-intuitive, since more water produces more vegetation, which should promote more insects, but it turns out that the native diversity is not impressed by this extra water. A few widespread and introduced species are the main beneficiaries of such conditions.

So, the message from these studies is that, in Los Angeles, we need to continue to work together to slow or prevent climate change, and we need to avoid having lawns and other water-extravagant landscapes. Native plantings watered by drip irrigation would be the best type of yard to promote insect diversity. Greater (native) insect diversity promotes (or is a result of) a healthier ecosystem, which favors a better standard of life for all of us living in L.A.

Publications: I am grateful to our wonderful and talented group of collaborators who have allowed us to extract meaning from the bags of insects we collect from our BioSCAN sites: Terry McGlynn, Emily Meineke (who has a new position at UC Davis- go Emily!), Christie Bahlai, Jane Li, Emily Hartop, and Max Adams. Also, I cannot thank enough our BioSCAN staff, Lisa Gonzalez and Estella Hernandez, along with the volunteers and work study students who help make the project possible. Finally, all of our 80+ site hosts who shared their properties with our traps are truly special people who care about the future of nature in our city. I hope that we can continue to bring you new insights and actionable results.

Adams, B.J., E. Li, C.A. Bahlai, E.K. Meineke, T.P. McGlynn, and  B.V. Brown. 2020. Local and landscape scale variables shape insect diversity in an urban biodiversity hotspot. Ecological Applications.

McGlynn, T. P., E. K. Meineke, C. A. Bahlai, E. Li, E. A. Hartop, B. J. Adams, and B. V. Brown. 2019. Temperature accounts for the biodiversity of a hyperdiverse group of insects in urban Los Angeles.  Proceedings of the Royal Society, B.

New life history observation for a Megaselia species

In the field in Brazil last month, a couple of fantastic colleagues found a new type of life history for a Megaselia (phorid fly species). Dayse Marques and Steve Marshall were walking on a trail and came across a group of caterpillars of the genus Euglyphis (Lasiocampidae).

Dayse noticed a small phorid fly on the back of one caterpillar, and Steve captured the apparent oviposition beautifully. They also were able to collect the fly, which appears to be an undescribed species (no big surprise there!).

Phorids are known to attack damaged, dying caterpillars, but oviposition on an apparently healthy living host is new. I hope that the caterpillar-rearers of the world will keep their eyes open to the possibility of primary phorid parasitism, and not dismiss them immediately as secondary scavenger attack by Megaselia scalaris or some other vulture-like species.

I thank Steve and Dayse for sharing their expertise, and Dan Janzen for his caterpillar ID.

Fly School 2019

Its time for our biannual course for dipterists, Fly School! From 23 June to 6 July, we will be getting together 6 instructors, 2 special guests, and 26 students (from 16 countries). It is two weeks of non-stop dipterology, enough to make you a truly fly-obsessed expert.

This will be the second time we have held Fly School; the first time was in 2017 at Harmony Pines, near Wrightwood, California. Our students had a great experience, and many of them were participants in last year’s International Congress of Dipterology in Windhoek, Namibia.

OLYMPUS DIGITAL CAMERA

This year, Fly School will be by the coast, halfway between Los Angeles and San Francisco, in beautiful Montaña de Oro State Park. I will post any great discoveries and news from the program. I hope that aspiring dipterists will consider taking our course and joining the fun! Announcements of the next Fly School will be on the website, dipteracourse.com.

update on phorid identification

One reader of my blog ““Zombie flies” are not in Saudi Arabia (at least, not yet)” , wrote me a private message, disagreeing that an unequivocal identification of Megaselia scalaris could be made, based on the published figure “C” in that paper. Technically, this reader is correct that one could theoretically assemble a group of other Megaselia that would be indistinguishable from M. scalaris based on this photo. The context is important, however, as M. scalaris is abundant in dead insects and frequently found in dead honey bees (I have seen this association from dead honey bees many times from various parts of the world). Thus, what I should have written is that based on the incomplete photo and the situation where the flies were found, it is almost certain that they are M. scalaris.

“Zombie flies” also not recorded from Egypt

Similar to my last post, the honey bee parasitizing phorid Apocephalus borealis was erroneously recorded from Egypt. The photo of the fly involved is clearly Megaselia scalaris (except Fig. 4B, the ovipositor of the fly, which is an unacknowledged use of one of my photographs). The offending paper is:

“THE FIRST RECORDS OF THE PARASITE ZOMBIE FLY (APOCEPHALUS BOREALIS  BRUES) ON HONEYBEE,APIS MELLIFERA IN EGYPT” by METWALLY M. KHATTAB & EL-HOSSENY, E. NOWAR.2014. International Journal of Agricultural Science and Research (IJASR)
Vol. 4, Issue 6, Dec 2014, 37-42

Interestingly, this paper assigned itself an impact factor of 4.3594!

“Zombie flies” are not in Saudi Arabia (at least, not yet)

A recent publication in the Journal of Apicultural Research supposedly documents the presence of the bee-parasitizing phorid fly Apocephalus borealis in Saudi Arabia. This seemed pretty unlikely to me, so I looked at the evidence they presented. Unfortunately, it appears that the flies were misidentified. Their figure “A” is of a syrphid fly, Eristalinus taeniops, while their figure “C” is of Megaselia scalaris. Both are scavengers in decaying filth.

I am not sure how this paper got published with such severe issues in identification. Step it up, Taylor & Francis!

Reference: Mohammed, S.E.A.R. 2018. First report of Apis mellifera carnica Ruttner (Hymenoptera, Apidae) in Saudi Arabia parasitized by a phorid parasitoid (Diptera: Phoridae). Journal of Apicultural Research. www.tandfonline.com/doi/full/10.1080/00218839.2018.1466760

ZADBI: Zurqui All-Diptera Biodiversity Inventory

giant sciarid fly

From a 4 hectare (about 9 acre) patch of cloud forest near San José, Costa Rica, a team of dipterists (fly researchers) have identified over 4000 species of flies, and extrapolations from this collecting suggest that the true total is 7,000 – 8,000. This incredible diversity was the result of the ZADBI project, funded by the US National Science Foundation. A team of talented and dedicated Costa Rican biologists sampled at the site, called Zurquí de Moravia, for an entire year, using several Malaise traps, regular light trapping, hand collecting and other methods. The resulting catch was prepared (mounted, pinned, slide-mounted, labeled) and sent to international experts on various fly families for identification.  The result was an eye-popping number of species, many of them new to science (especially in the families of smaller flies).

Leading the way were the gall midges, or Cecidomyiidae, which were represented by at least 800 species, almost all of the probably undescribed. During the course of the project, cecid expert Dr. Mathias Jaschhof actually described some of the new species, including those that belonged in a new genus he named Zadbimyia in honor of the project (there were 19 of the 22 species of this genus alone at Zurquí).

Second most species rich were the phorids, whose numbers were so large that I am still reeling from the effort of trying to understand their diversity (with help from Maria Wong, Giar-Ann Kung, John Hash, and others). The 400 species we identified is surely just part of what is really there.

There were hundreds of species of other families of flies as well, including lots of strange and wonderful new things. It will be years before we can finish identifying everything, but the project gives us some important insights into tropical Diptera diversity. It is also a testament to how effective a large group of dipterists can be, identifying thousands of specimens of one of the least-known biotas in the world.

I hope to bring you many more details about the results from the project, but for now, here are links to the two recently published papers:

Borkent, A., B. V. Brown, P. H. Adler, D. S. Amorim, K. Barber, D. Bickel, S. Boucher, S. E. Brooks, J. Burger, Z. L. Burington, R. S. Capellari, D. N. R. Costa, J. M. Cumming, G. Curler, C. W. Dick, J. H. Epler, E. Fisher, S. D. Gaimari, J. Gelhaus, D. A. Grimaldi, J. Hash, M. Hauser, H. Hippa, S. Ibáñez-Bernal, M. Jaschhof, E. P. Kameneva, P. H. Kerr, V. Korneyev, C. A. Korytkowski, G. Kung, G. M. Kvifte, O. Lonsdale, S. A. Marshall, W. N. Mathis, V. Michelsen, S. Naglis, A. L. Norrbom, S. Paiero, T. Pape, A. Pereira-Colavite, M. Pollet, S. Rochefort, A. Rung, J. B. Runyon, J. Savage, V. C. Silva, B. J. Sinclair, J. H. Skevington, J. O. Stireman III1, J. Swann, P. Vilkamaa, T. Wheeler, T. Whitworth, M. Wong, D. M. Wood, N. E. Woodley, T. Yau, T. J. Zavortink, and M. A. Zumbado. 2018. Remarkable fly (Diptera) diversity in a patch of Costa Rican cloud forest: why inventory is a vital science. Zootaxa 4402: 53-90

 

Brown, B.V., A. Borkent , P.H. Adler , D.S. Amorim, K.Barber, D. Bickel, S. Boucher , S.E. Brooks, J. Burger, Z.L. Burington, R.S. Capellari, D.N.R.Costa, J.M. Cumming , G. Curler, C.W. Dick, J.H. Epler, E. Fisher, S.D. Gaimari, J. Gelhaus, D.A. Grimaldi, J. Hash, M. Hauser, H. Hippa, S. Ibáñez-Bernal, M. Jaschhof, E.P. Kameneva, P.H. Kerr, V. Korneyev, C.A. Korytkowski , G. Kung, G.M. Kvifte, O. Lonsdale, S.A. Marshall, W. Mathis, V. Michelsen, S. Naglis, A.L. Norrbom, S. Paiero, T. Pape, A. Pereira-Colavite, M. Pollet, S. Rochefort, A. Rung, J.B. Runyon, J. Savage, V.C. Silva, B.J. Sinclair, J.H. Skevington, J.O. Stireman III, J. Swann, F.C. Thompson, P. Vilkamaa, T. Wheeler, T. Whitworth, M. Wong, D.M. Wood, N. Woodley, T. Yau, T.J. Zavortink, & M.A. Zumbado. 2018. Comprehensive inventory of true flies (Diptera) at a tropical site. Communications Biology (Nature). 

 

tachinid fly, photo by W. Porras

 

 

 

 

 

More on greenbottle flies

Questions remain about differentiating greenbottle flies (Lucilia spp.) from muscid lookalikes (Neomyia) in iNaturalist photos. I wrote previously that the distribution of the tomentum (silver reflection caused by microtrichia) would help; below are some further photos to aid in this process.

Male Neomyia

Male Lucilia

Female Neomyia

Female Lucilia 

In each instance, you can see that the tomentum in Lucilia extends much farther dorsally on the frons than in Neomyia.

There was also the tougher question about separating Lucilia cuprina from L. sericata in photos. This is more difficult, because the main character used by the calliphorid expert, Terry Whitworth, is on the back of the head, usually out of sight in photos. There are supporting characters, however, on the dorsum (top) of the thorax. If you look at the humeral callus (“h”, below) and the notopleuron (the triangular area marked “n”), there are a  few tiny setulae along the posterior margins. In L. sericata, there are usually around 6, in L. cuprina 2-3. If you can see that kind of detail in an iNaturalist photo, then you can make a call; otherwise, I suggest leaving them as “Lucilia sp.”

sericata thorax

cuprina thorax