July 18, 2020

Bombus sonorus/Bombus pensylvanicus: evidence of hybridization?

Bombus pensylvanicus was described as a species in 1863 (by Cresson). In 1873, B. sonorus was described as a species (by Say). Franklin (1912) recognized them as species, but Milliron (1973) and Williams (2014) recognized B. sonorus as a subspecies of B. pensylvanicus. There have been reports of "intermediates" between Bombus pensylvanicus and B. sonorus in Texas and Mexico. However, these reports don't describe very well, if at all, the phenotype of the intermediates that they're reporting. Yet these alleged intermediates have influenced some taxonomists to demote B. sonorus to a subspecies under B. pensylvanicus. Unpublished, preliminary genetic data also contributed to this demotion. None of this evidence is documented very well in the published literature. Because of the longstanding and remaining uncertainty, I'm on a quest to set the record straight--with well documented evidence.

My objective is to find genetic/phenotypic evidence to support or refute the hypothesis of hybridization. I am collecting specimens of both species at locations where both species can be found pollinating the same plant. Then, I'll extract DNA and sequence a mitochondrial gene (I've already confirmed that the two species are genetically unique). If I find the DNA sequence of B. sonorus in a specimen that is phenotypically B. pensylvanicus (and vice versa), that would be evidence of hybridization at some point in the past.

What might constitute a "hybrid phenotype"? Labougle (1990) states: “...it is sometimes difficult to place a Mexican specimen in either subspecies because there are specimens with the coloration of the scutellum...intermediate between the two taxa.” The scutellum is the region of the pronotum between the base of the wings. But what does intermediate coloration mean, exactly? The author does not explain. Among males, intermixed black and yellow hairs is common in B. pensylvanicus so this cannot constitute such evidence. However, among females, B. pensylvanicusis described as having a scutellum usually covered in only black hairs, while in B. sonorus, only yellow hairs. If intermixed hairs is the "hybrid trait" reported in Texas and Mexico, we can discount this as evidence of hybridization if we find this trait in specimens far outside the zone of overlap (sympatry) between the two species--in places where it would be impossible for hybridization to occur. And there are indeed examples of this:

Female B. pensylvanicus with mixed yellow/black hairs on scutellum

@jane41, @mob-critters

Posted on July 18, 2020 20:37 by pfau_tarleton pfau_tarleton | 0 comments | Leave a comment

May 17, 2020

Water beetles

Water beetles aren't a monophyletic group and can be found throughout the Order Coleoptera. So displaying or searching for water beetles requires a bit more effort. Here are links to most aquatic and semi-aquatic beetles found in the U.S. So if you find something that you know or think is a water beetle, scroll through this collection of species to help narrow down your identification.

Water beetles of the U.S. (change location to whatever you wish). This includes the following groups: Hydrophilidae, Dytiscoidea, Haliplidae, Gyrinidae, Scirtidae, Noteridae, Amphizoidae, Hydroscaphidae, Lutrochidae, Dryopidae, Elmidae, Heteroceridae, Limnichidae, Psephenidae, Sphaeriusidae.

Posted on May 17, 2020 15:40 by pfau_tarleton pfau_tarleton | 2 comments | Leave a comment

March 29, 2020

Dissecting scope and focus stacking

As a kid, I always had my trusty microscope at my desk (a tiny department store model). And I used it regularly.

Since my camera does a poor job of capturing the tiny things--and because I really want to see the tiny things--I bought a dissecting scope. It was on sale 50% off. For the light, the LED ring works well.

The scope has a port for mounting a DSLR camera body, but those cost more money. So I'm using my smartphone with an adapter. A DSLR camera body would be better though.

Then I needed a camera app with the right controls (an infinite focus depth setting is critical), so I'm using Open Camera. Be sure to turn off the flash and auto exposure setting so the brightness stays consistent across focus levels.

When taking pics for focus stacking, I start taking pics focused at the upper plane and then focus downward in small increments taking a photo at each depth. The specimen CANNOT move or twitch at all during this process otherwise the images won't align.

And then, for the focus stacking, I'm currently using PICOLAY software. Before each focus stacking session, be sure to set the option to "Add original name to py file", otherwise it gives the resulting file a generic name. And set stacking parameters to "Align images 2x". From there, it's automagical.

Lastly, I use the Windows Photos app for cropping and enhancement. The "Clarity" adjustment, in particular, really makes them pop.

Posted on March 29, 2020 13:35 by pfau_tarleton pfau_tarleton | 10 comments | Leave a comment

March 15, 2020

The Tiny Beetle Club

To be a member of the Tiny Beetle Club, you have to be 3 mm or less in length. Here are the members of my Tiny Beetle Club.

The world's smallest beetle is evidently 0.325 mm long. The smallest I've seen so far is about 1 mm.

Posted on March 15, 2020 00:00 by pfau_tarleton pfau_tarleton | 0 comments | Leave a comment

March 03, 2020

Super cool moss project!

Check it out here: https://www.inaturalist.org/projects/physcohunt

Be sure and click "Read more" and download their training packet.

Tips on identifying and collecting:

Here's my contribution so far:

Posted on March 03, 2020 23:39 by pfau_tarleton pfau_tarleton | 0 comments | Leave a comment

March 01, 2020

Anemone edwardsiana: gaps in distribution?

There are some gaps in the observational distribution of Anemone edwarsiana. This species appears to prefer moist canyons of the Balcones Escapement. Here are the current observations:

Observational gaps occur between Leaky and Boerne and in the vicinity of San Marcos. I wonder if these are real gaps (they just don't occur there), or if folks just haven't noticed them yet?

Here's a guide to distinguishing species for those interested in watching for them. March is peak bloom time.

I'm tagging some top plant observers in these areas who might be interested--feel free to tag others.

@companyink, @beeblossomseeds, @beschwar, @entomike, @stephenramirez
@mattgeo1990, @donkeylady, @ygg_huur, @ygg_huur

Posted on March 01, 2020 15:19 by pfau_tarleton pfau_tarleton | 2 comments | Leave a comment

February 18, 2020

Mantidflies in Florida

I'm reaching out to observers in central Florida to keep an eye out for an apparently unique mantidfly documented in that area. Here are some observations:

If you find something that looks like this, capture it, post a pic, and contact me. It may just be an unusual variation of a common species, but it has a very unique set of characteristics and might be a new species. If we have a specimen in hand, I can sequence the DNA and send the critter itself to a taxonomic expert for further characterization.

@ryancooke, @gaudettelaura, @brennafarrell, @joannerusso, @mbelitz, @joshuadoby, @ericpo1, @scottsimmons, @j_appleget, @vijaybarve, @stevecollins, @marykeim, @floridensis

Posted on February 18, 2020 16:57 by pfau_tarleton pfau_tarleton | 18 comments | Leave a comment

February 15, 2020

Spring Timberlake Bioblitz

If the weather is cooperative, I'll be hosting another bioblitz at Timberlake Field Station in March or April. It will be the weekend of March 21st (or the 28th if the weather is bad). March 28th (or April 4th if the weather is bad) (Friday - Sunday).

Tarleton State University’s Timberlake Biological Field Station is an educational and research facility located on the Colorado River in the heart of Texas--midway between Austin and Abilene. The 790 acre property has approximately 3 miles of river frontage.

Here's the link to detailed info about Timberlake: https://docs.google.com/document/d/19D_D0b94QvtB72GR8e5cSH8XHXFSe9DS69zffjRrbtw/edit?usp=sharing

I'm tagging some folks that have expressed an interest and some nearby folks. Don't be offended if you're not tagged here--I loose track easily! Feel free to tag anyone else that you know might be interested.
@mikef451, @sambiology, @centratex, @davedenlinger, @lovebirder, @greglasley, @tweedledee, @alflinn329, @gpstewart, @ncowey, @tvasquez, @kbbutler, @mikaelb, @sawwhet, @sheliahargis, @jeffmci9, @sambiology, @wildcarrot, @catenatus, @brentano, @bosqueaaron, @gcwarbler, @annikaml, @mchlfx, @oddfitz, @tadamcochran, @rymcdaniel, @nathantaylor, @entomike, @nanofishology, @galactic_bug_man, @connlindajo, @k8thegr8, @squaylei2000, @ecarpe, @jeffmci9

Posted on February 15, 2020 02:27 by pfau_tarleton pfau_tarleton | 30 comments | Leave a comment

January 18, 2020

Annotation resolution: phenology

I don't do new year resolutions, but I'll make one exception. Well, two. I'm going to do lots of annotation (and not just phenology) from here on out. And take breaks from doing it to use the new piece of exercise equipment next to my computer so that I'll have more energy to observe stuff outside.

I discovered that you can filter observations that don't have annotations, so I'm doing phenology of TX/OK anemones now (note all the settings): https://www.inaturalist.org/observations/identify?reviewed=true&quality_grade=needs_id,research&page=2&order_by=random&taxon_id=883652&place_id=18,12&without_term_id=12

And here's an interesting article about plant phenology.

And here's an amazing document covering all aspects of plant phenology.

Setting yourself up for an annotation session:

  1. go to Identify mode
  2. select the taxa (e.g. Lepidoptera or flowering plants) and the place (anywhere in the world as no local expertise is required)
  3. go to Filters and select Research Grade in addition to Needs ID
  4. open More Filters and select Without Annotation and a relevant option for your taxa
  5. click through each observation (with the Annotations tab selected) and annotate away!

Once selecting all the options, you can bookmark the resulting URL for quick access later.

Posted on January 18, 2020 14:05 by pfau_tarleton pfau_tarleton | 1 comment | Leave a comment

December 31, 2019

Accurate geotagging

My camera has a built-in GPS, but it usually takes forever to get satellite readings and so many of my pics are missing the geotag. So, when I'm out on an observing trek and want to make sure I get accurate locations, I'm using the GPXLogger app on my phone in two different ways. I start the GPXLogger app to record my trek (I have it set to record my location every 40 seconds or so) and then, later, I sync my pics with the locations using GPicSync software on my computer (it ties pics with locations based on the timestamp). But I don't trust that GPXlogger is always working, so as a backup, I take a pic of the GPXLogger screen every so often to document the coordinates in my camera roll.

Posted on December 31, 2019 23:38 by pfau_tarleton pfau_tarleton | 0 comments | Leave a comment