Ημερολόγιο της/του charles161

Hi Everyone!

With Gall Week quickly approaching this Saturday, I'd thought I would make a post highlighting some specific taxa that I am seeking to enhance my study on the diversity of the gall wasps in the tribe Diastrophini.

For a quick refresher, the Diastrophini are gall inducing and gall usurping wasps associated with the plant family Rosaceae. Diastrophini currently has 5 genera:

Diastrophus (19 species described)- gall inducers on brambles (Rubus) and cinquefoils (Potentilla, Drymocallis, Horkelia, Horkeliella[?], and possibly other closely related genera). Found in Nearctic, Palearctic, Neotropics

Xestophanes (3 species described)- gall inducers on Potentilla. Restricted to Palearctic.

Periclistus (18 species described)- gall usurpers of Diplolepis rose galls. Found in Nearctic and Palearctic.

Synophromorpha (4 species described)- gall usurpers of Diastrophus galls on Rubus. Found in Nearctic

Of these taxa my studies are primarily focused on uncovering the diversity of Diastrophus and Synophromorpha in the Nearctic and revealing how all these taxa are related through phylogenetics. Our lab here at Penn State is gearing up to do genome scale sequencing of these wasps, and we would love to receive specimens contributed from iNaturalist's rich community of explorers and enthusiasts.

This year I am especially interested in getting access to more galls and insects associated with cinquefoils from the Western US and Rubus from Southern US.

The Western US is a treasure cove for undiscovered biodiversity in the gall world. The bulk of Diastrophus's biodiversity is described from eastern US, and the western states have an even greater diversity of cinquefoils that could serve as potential hosts for these wasps. Of the described taxa I am particularly interested in figuring out the biology of Diastrophus fusiformans. This species was described in the 1890s from an unspecified species of cinquefoil, and I have yet to find/ rear wasps that match the type specimens perfectly. Many naturalists and I have fund undescribed galls on Potentilla, Horkelia, Drymocallis, and Horkeliella; and any of these hosts could be the host plant for D. fusiformans. These galls typically occur as swellings on the stem and petioles of their hosts but some even form cryptic galls that are hidden in the stem.

Horkelia is an endemic genus with its diversity concentrated in California and western Oregon. I have received/ reared specimens from 2 different Horkelia species that were distinct from each other morphologically and genetically. I would be elated to get even more samples from this genus, as I believe I have only scratched the surface of the species that utilize this host lineage.

Horkeliella is another genus of cinquefoil found in California. A couple years ago, Matt Purdy found these galls on Horkeliella congdonis (https://www.inaturalist.org/observations/130700577), and it is incredibly likely that these galls are caused by wasps in the genus Diastrophus.

Another diverse group of cinquefoils with Diastrophus galls is Drymocallis. So far I have found at least 5 different species of gallers associated with this genus. There is higher diversity of this genus in western US than in the east where there is predominantly one species, Drymocallis arguta. So far, each new host I have sequenced/ reared wasps from has been a different species.

In addition to these galls on cinquefoils, I would also love to get Rubus galls from southern regions North American. I am working on describing a new species of Synophromorpha reared from root galls on Rubus trivialis, which is one of the dominant species of Rubus in the southern US. I currently only have one specimen of the inquiline, and I would like to get more for a type series. I am also curious if there are other types of galls on this host besides the roots and would be interested in seeing if they are separate species from the root gallers. Synophromorpha kaulbarsi is described from a single specimen from Mexico, and its unknown what Diastrophus sp this wasp attacks or what host it is from, so any Rubus galls found in that region or further south in the US could help solve this puzzle.

If you find any galls that you would be willing to send, I can handle the rearing efforts on my end. If you could package the galls in a ziploc bag with airholes to prevent them from drying out and include the collection information on a note card alongside the galls in the ziploc as well that would be wonderful . The best package to put them in is probably a small box with some sort of padding inside or a padded envelope.

You can send them to the following address:

Charles Davis

112 Merkle Laboratory

Department of Entomology

Penn State University

University Park, PA, 16802

Let me know if you have any further questions and I am looking forward to seeing what galls we find in the coming weeks!

Hello iNaturalists and Gall Enthusiasts!

If you don't know me, My name is Charles Davis and I am an Entomology PhD Candidate at Penn State studying the taxonomy and evolution of gall wasps in the family Cynipidae. One of the main chapters of my dissertation is a revision of the genus Diastrophus within the Nearctic (North America). Diastrophus is a group of gall wasps that makes galls on plants of the family Rosaceae, mainly cinquefoils of the tribe Potentilleae and brambles of the genus Rubus. These gall wasps occur across the Holarctic (Northern Hemisphere) and there is even a species in the Neotropics (South America), but the bulk of the diversity is found within North America. There are 19 described species, but no one has actively worked on this group in over 20 years and there have been no new species in North America in over 100 years!

The main goal of my dissertation is to bring stability to this group of insects by assessing the validity of the species using an integrative dataset including morphological, biological and genetic data. As I evaluate the identities of these species, I also get the opportunity to describe new species of Diastrophus when appropriate.

One area of North America which has been under estimated in it's diversity for these insects is the West. As it stands now, there are only 4 species of Diastrophus that occur east of the Mississippi: Diastrophus austrior, Diastrophus kincaidii, Diastrophus turgidus, and Diastrophus fusiformans. Diastrophus kincaidii and D. austrior both make multichambered stem galls on Rubus parviflorus, and it is likely that they are the same species. Diastrophus turgidus creates multichambered stem galls on Rubus idaeus strigosus. Diastrophus fusiformans induces multichambered galls on the petioles and stems of an herbaceous cinquefoil in the genus Potentilla.

Whiles I have been able to either collect or source samples and specimens of the Rubus associated Diastrophus in the West, I have not been as fortunate with collecting D. fusiformans. There are currently only a few species described from Potentilla, and across literature it is generally assumed that these gallers are not as diverse as their Rubus associated congeners.

The only western cinquefoil galler is D. fusiformans, but at its description the host plant's species was not specified only that it belonged to the genus Potentilla. Across museum records, Diastrophus reared from Potentilla gracilis is considered to be D. fusiformans, but many of these specimens do not match the original specimens used to described the species. Potentilla gracilis is a very likely suspect for the host plant as it is one of the most common cinquefoils in the western United States, but the species is extremely polymorphic as there are several varieties across its geographic range. Furthermore, when D. fusiformans was described most cinquefoils were lumped into Potentilla, and there has been a decent amount of shifting since then with genera such as Drymocallis, Horkelia, and Horkelliela being resurrected/ established. There could be just as likely that D. fusiformans originates from galls one of these plants genera as it is likely to come from galls from Potentilla (sensu stricto).

Through my field work in the Idaho area and from contributions from several enthusiasts, we have found multiple species of galls from cinquefoils in Drymocallis, Horkelia and Potentilla. Of the wasps I have reared from these cinquefoils so far, the most likely culprit to the mystery of D. fusiformans are galls of one of the varieties of P. gracilis. I have received galls from the petioles of P. gracilis gracilis, and I have personally collected petiole galls from P. gracilis, but so far none of the adults I have reared from these galls have matched the wasps in the type series. I have also not seen galls on P. gracilis that make perceptible swellings of the stem like the galls of the type series. However, I have collected P. gracilis stems that house cryptic, imperceptible galls induced by an undescribed Diastrophus species! Additionally, the original wasp specimens used to describe D. fusiformans are from Colorado, while the majority of the fresh material I have examined originates from the Pacific North West.

I hypothesize D. fusiformans is on a variety of P. gracilis that I have yet to collect, or it is present only on a variety that is found within CO. I am hoping to do more field work out west soon to collect more galls across these amazing plants, but it is unlikely that I will be able to get complete coverage of P. gracilis's enormous range. If you want to help me solve the mystery of this elusive gall wasp species, please comment below, reach out to me via iNaturalist Dms, or email me at ckd5444@psu.edu and ckd.ento.eco.evo@gmail.com!

Massive thanks to these iNaturalists for contributing samples:
@lumenal
@thurmanjohnson
@friesen5000
@annieliveoak
@chris_nelson
@graysquirrel
@wisel
@ajwright