Explaining Science – vermiform mites

You have heard of mites – minute arachnids that have four pairs of legs when adult, are related to the ticks and live in the soil, though some are parasitic on plants or animals. But what are vermiform mites? Maybe you have heard of vermi-compost, a composting technique that uses worms (like your earthworm in the garden) to decompose organic matter. So vermiform mites are mites with a body shape like a worm:

worm-shaped nematalycid Osperalycus

Why are they shaped like a worm, you may ask – To find out more I interviewed Samuel Bolton, former PhD student in the acarology collection at our museum, now Curator of Mites at the Florida State Collection of Arthropods. Sam’s main research interest is in mites that live on plants and in the soil, especially Endeostigmata, a very ancient group of mites that dates back around 400 million years, before there were any trees or forests. Sam’s PhD research with Dr. Hans Klompen here at OSU, was focused on a small family (only five described species) of worm-like mites, called Nematalycidae.

side note: You may have heard of Sam’s research in 2014 when he discovered a new species of mite, not in a far-away country, but across the road from his work place in the museum.

When Sam started his research it was not clear where these worm-like mites in the family Nematalycidae belong in the tree of life. To find out Sam studied several morphological characters of Nematalycidae and other mites. He focused in particular on the mouth-parts of this group. As he learned more about the mouth-parts of this family, he found evidence that they are closely related to another lineage of worm-like mites, the gall mites (Eriophyoidea). Eriophyoidea have a sheath that wraps up a large bundle of stylets. They use these stylets to pierce plant cells, inject saliva into them and suck cell sap.
Although Nematalycidae don’t have stylets, one genus has a very rudimentary type of sheath that extends around part of the pincer-like structures that have been modified into stylets in Eriophyoidea.

So what did Sam and his co-authors discover?

“.. Not only are gall mites the closest related group to Nematalycidae, but the results of our phylogenetic analysis places them within Nematalycidae. This suggests that gall mites are an unusual group of nematalycids that have adapted to feeding and living on plants. Gall mites use their worm-like body in a completely different way from Nematalycidae, which live in deep soil. But both lineages appear to use their worm-like bodies to move around in confined spaces: gall mites can live in the confined spaces in galls, under the epidermis (skin), and in between densely packed trichomes on the surface of leaves;  Nematalycidae live in the tight spaces between the densely packed mineral particles deep in the soil.”

This research potentially increases the size of Sam’s family of expertise, Nematalycidae, from 5 species to 5,000 species. We have yet to confirm this discovery, but it is highly likely that gall mites are closely related to Nematalycidae, even if they are not descended from Nematalycidae. This is interesting because it shows that the worm-like body form evolved less frequently than we thought. This discovery also provides an interesting clue about how gall mites may have originated to become parasites. They may have started out in deep soil as highly elongated mites. When they began feeding on plants, they may have used their worm-shaped bodies to live underneath the epidermis of plants. As they diversified, many of them became shorter and more compact in body shape.

I wish I could tell you now to go out and look for these oddly shaped mites yourself, but you really need a microscope. Eriophyoid mites are minute, averaging 100 to 500 μm in length. For your reference, an average human hair has a diameter of 100 microns.

eriophyoid Aceria anthocoptes

Reference:

Bolton, S. J., Chetverikov, P. E., & Klompen, H. (2017). Morphological support for a clade comprising two vermiform mite lineages: Eriophyoidea (Acariformes) and Nematalycidae (Acariformes). Systematic and Applied Acarology, 22(8), 1096-1131.

 

About the Authors: Angelika Nelson, curator of the Borror Laboratory of Bioacoustics, interviewed Samuel Bolton, former PhD graduate student in the OSU Acarology lab, now Curator of Mites at the Florida State Collection of Arthropods, in the Florida Department of Agriculture and Consumer Services’ Division of Plant Industry.

 

Explaining Science – taxonomy of parasitoid wasps

Professor Norm Johnson, Director of our C.A. Triplehorn Insect Collection, studies systematics of parasitoid wasps and so do his students. Graduate student Elijah Talamas collected many insect specimens during his PhD work at Ohio State and revised several taxa. Recently he published a photographic catalog of some primary types of parasitoid wasps in the large insect order Hymenoptera.

I contacted Elijah in his current position at the The Florida Department of Agriculture and Consumer Service and asked him to give us some insights into his life as a researcher. He recently published results from work he did as a a postdoctoral fellow for the U.S. Department of Agriculture at the National Museum of Natural History in Washington DC:

Elijah TalamasElijah: “I am the curator of Hymenoptera (bees, ants and wasps) at the Florida State Collection of Arthropods, which is part of the Florida Department of Agriculture and Consumer Services. I have broad interests in the taxonomy, morphology, and evolution of platygastroid wasps, especially groups with potential for biological control. I was trained by Dr. Norman Johnson at The Ohio State University, and maintain active collaboration with him and members of his lab.”

Angelika: “What species did you study?”

Elijah: “As a taxonomist, I study many species and genera in the superfamily Platygastroidea. These are parasitoid wasps that require development in a host to complete their life cycle, i.e. their larvae live as parasites that eventually kill their hosts. The past few years have focused on the genus Trissolcus which are parasitoids of stink bug eggs.”

(Angelika’s note: You may recall that the brown marmorated stink bug is an invasive species from Asia, now found in the eastern half of the U.S., as well as California, Oregon, Washington, Arizona, New Mexico and Texas. You may have seen one in your home, especially in late fall when they are looking for a sheltered place to overwinter)

Angelika: “What was your research questions in this particular study?”

Elijah: “A typical taxonomic project will “revise” a genus and involves many questions: What are the characters that define the genus? How many species does it contain and how do we identify them? The separation of organisms into species is the foundation of organismal biology and this is one of the jobs of a taxonomist.”

brown marmorated stink bugAngelika: “What do we know already, and why is it important to know this?”

Elijah: “We know that many parasitoid wasps attack the eggs of agricultural pests. This is important because they are often the best, and sometimes only solution to control numbers. The invasive brown marmorated stink bug is an invasive pest that can be found in Ohio, and it is not controlled by natural enemies in the United States. However, there are parasitoid wasps in its native distribution in Asia that kill the stink bugs’ eggs very efficiently. Biological control research about these wasps requires thorough study of their morphology to ensure that
species are properly identified.”

Angelika: “How did you study this question?”

Elijah: “I study parasitoid wasps by examining them under a microscope, documenting their anatomical structures, and the variability that can occur within a species. This often requires examination of specimens from all over the  world, and sometimes international travel is required to access specimens in foreign institutions and to collect fresh material. I rely heavily on photography to document and share information about these wasps, but I also use other techniques, including scanning electron microscopy and analysis of DNA.”

When looking at detailed features one may notice that some of them are different from how they were originally described and the specimen may be more closely related to to another group of specimens. This means that sometimes the classification of the species needs to be revised and renamed to reflect these new relationships. For example, in the figures below you can see the holotype, the specimen that was used to describe the species Psilanteris nigriclavata. This species was originally described with the name Opisthacantha nigiclavatus in 1905. The specimen was embedded in glue, which obscured some of its diagnostic characters and hampered a clear assessment of its identity. As part of this project, Elijah dissolved some of the glue and determined that it shared characteristics with other species in the genus Psilanteris. Thus this species was moved to this genus and now operates under the name Psilanteris nigriclavata.

62 head, mesosoma, metasoma, lateral view; 63 head and mesosoma, anterodorsal view (sk=skaphion); 64 head and mesosoma, lateral view. Scale bars in millimeters.

Angelika:  “Why is this research important?”

Elijah: “Taxonomy informs us about many aspects of the biological world. It is the science that reveals the planet’s biological diversity and discovers the evolutionary relationships between organisms. It enables other disciplines to identify organisms for the studies of behavior and ecology, and applications with large scale societal impact, such as biological control of invasive pests.”

Angelika: “What do you hope to have achieved with this study?”

Elijah: “For parasitoid wasps in the superfamily Platygastroidea, this study provides photographs of all holotype specimens in the National Musuem of Natural History and makes them freely available online. Taxonomists all over the world now have immediate access to these specimens through the internet, enabling them to make better informed decisions for classification, and more refined hypotheses about evolution.”

Let us know if you have any questions, we would like to hear form you!

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Some explanations you may find helpful:

Anterodorsal means in front and toward the back.

A holotype is a single type specimen upon which the description and name of a new species is based.

Lateral means from the side.

The body of arthropods is composed of three parts, from front to back, the prosoma, mesosoma, metasoma.

A parasitoid is an insect whose larvae live as parasites that eventually kill their hosts.

Superfamily is an intermediate classification rank directly above family and might contain one or more related families. For example, Muroidea, a superfamily of rodents, contains six families of rats, mice, hamsters and gerbils. Taxonomists use several levels to classify living things. They follow the International Code of Zoological Nomenclature which specifically mentions superfamily, family, subfamily, tribe, subtribe, genus, subgenus, species, subspecies.

Reference: Talamas, E. J., Thompson, J., Cutler, A., Schoenberger, S. F., Cuminale, A., Jung, T., … & Alvarez, E. (2017). An online photographic catalog of primary types of Platygastroidea (Hymenoptera) in the National Museum of Natural History, Smithsonian Institution. Journal of Hymenoptera Research, 56, 187.

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and the Outreach and social media manager for the museum. Here she interviewed Elijah Talamas, currently Postdoctoral researcher with the U.S. Department of Agriculture at the National Museum of Natural History, Smithsonian Institution in Washington DC.

Bat sounds

Bats are social mammals that use a repertoire of vocalizations to communicate with each other and to move around in the environment.

To detect obstacles and prey in their environment, bats emit a series of ultrasounds, very high-pitched sounds above 20,000 Hz, beyond our range of hearing. As a bat flies and calls, it listens to the returning echoes of its calls to build up a sonic image of its surroundings. Bats can tell how far away something is by how long it takes the sounds to return to them, how big the target is based on the strength of the returning signal, and what shape the target has based on the spectral pattern of the returning sound waves. We call this process echolocation.

Individual bat species echolocate within specific frequency ranges that suit their environment and prey types. This means that we can train ourselves to identify many bats by listening to their calls with bat detectors.

Let’s LISTEN to recordings of the little brown bat (Myotis lucifugus) and the big brown bat (Eptesicus fuscus) for comparison. – But how can we listen, if we cannot hear their calls? Let’s use a trick: When we slow down the recordings by a factor of 10, the calls are transposed to 10 times lower pitch and become audible to us.

Note: To make the sounds visible in sonograms we plotted frequency in thousands of cycles per second (kilohertz, kHz) on the vertical axis versus time in seconds on the horizontal axis. The varying intensity of colors ranging from dark blue (low intensity or quiet) to red (high intensity or loud) indicates the amplitude or loudness of each call. Amplitude is also shown in the top part of each figure with larger waves representing louder calls.

Little brown bat: Calls last from less than one millisecond (ms) to about 5 ms and sweep from 80 to 40 kHz, with most of their energy at 45 kHz.

sonogram of little brown bat Myotis lucifugus calls

Call series of a little brown bat Myotis lucifugus

 

Big brown bat: Calls last several milliseconds and sweep from about 65 to 20 kHz, and are thus lower pitched than calls of little brown bats.

bigsonogram of brown bat Eptesicus fuscus echolocating calls

Call series of a big brown bat Eptesicus fuscus

 

 

The above call series were recorded when the bat is generally surveying its environment, but what happens when it actually detects prey? Listen to this feeding buzz of a little brown bat:

sonogram of feeding calls of little brown bat

Feeding calls of a little brown bat Myotis lucifugus

 

When closing in on prey, a bat may emit 200 calls per second.

What might sound to us like the bat is getting excited – don’t you talk faster when you are excited about telling something? – this rapid series of calls actually helps the bat to pin-point the exact location of its prey, then it swoops in, and GULP – dinner is served, or not!

 

We hope you enjoyed listening to these bat sounds; if you have any questions please contact Angelika Nelson.794@osu.edu, curator of the animal sound archive at The Ohio State University.

The Ohio State University - logo

 

All recordings are archived with the Borror Laboratory of Bioacoustics (BLB.OSU.EDU) at The Ohio State University.

Summer in the field

This is the time when many students and faculty spend their days in the field doing research or attending conferences and meetings where they present their latest research results. Follow us on social media #ASCinthefield. We will not post here until the beginning of classes on August 22.

Have a great summer!

 

EEOB students experience charismatic creatures of the tropics

students in front of sign for Metropolitan nature park

Tropical Behavioral Ecology and Evolution class at the entrance to the Smithsonian Tropical Research Institute canopy crane, Metropolitan Nature Park, Panama City, Panama. Photo credit: Ryan McCarthy.

For the Tropical Behavioral Ecology and Evolution course in Panama, we established independent research projects, networked with the internationally-renowned Smithsonian Institution, got to know Panamanian culture, and made new friends. In addition, we had the opportunity to see some very charismatic Panamanian creatures, including the three-toed sloth (Bradypus variegatus). Attracted by their soothing movements, mischievous smiles, and tendency to hug things, I have long desired to see one of these slow, long-armed teddy bears of the jungle.

The chance to see a sloth came during a visit to Metropolitan Nature Park, where our group was preparing to board a canopy crane. Suddenly, while waiting excitedly to be lifted into the tropical rainforest canopy, out rang the call of, “İPerezoso!” the Spanish word for sloth, which also means “lazy.” All attention was diverted to a nearby forest edge, where a baby three-toed sloth was descending vines and trees, moving toward the ground.

We learned from one of the crane operators that sloths go to the ground to poop, a risky endeavor that makes them vulnerable to predators. It is thought that movement to the ground may benefit the moth and algae associates that live on a sloth’s coat, which the sloth relies on for camouflage. Regardless of its biological function, our group capitalized on the little sloth’s potty break as a photo opportunity.

adult sloth in tree

Adult sloth high in the canopy of an Anacardium excelsum tree. Photo credit: Ryan McCarthy.

When the crane was ready to take another group into the canopy, we begrudgingly pulled ourselves away from the baby sloth. Little did we know that we would see mama sloth, poised in the canopy and waiting for her little one’s return!

Our earth’s tropical rainforests are full of amazing biodiversity. The story of the sloth’s epic journey to the forest floor is just one of many biological sagas playing out in nature. You don’t have to go to the jungle to make amazing discoveries—check out a local natural area today!

 

Kali Mattingly, EEOB PhD candidateAbout the Author: Kali Mattingly is a PhD student in Steve Hovick’s lab studying population ecology and genetics of invasive plants. Kali recently participated in the Tropical Behavioral Ecology and Evolution course in Panama under Dr. Rachelle M. M. Adams and Dr. Jonathan Shik.

Squirreling in the Pacific Northwest

You may have heard that researchers discovered a new species of flying squirrel. These squirrels had lived in plain sight for decades but only recently did Brian Arbogast and colleagues investigate the DNA of some of these animals. Their findings were revealing: The Pacific squirrels cluster separately from the northern and southern flying squirrel. The researchers analyzed mitochondrial DNA as well as microsatellite data to reveal this new evolutionary relationship.

Note: Mitochondrial DNA and microsatellites are parts of a species’ genome that are regularly used to construct evolutionary trees. In addition to the DNA in every cell’s nucleus in our body, mitochondria, the energy powerhouses in our cells, have their own genome. This mitochondrial genome is relatively small, is inherited from the mother only and has relatively high mutation rates. It is like a small clonal lineage within an organism which makes it ideal for evolutionary studies.   Microsatellites are short sequence repeats in the nuclear genome that do not produce proteins. Thus they are free to mutate at a higher rate than coding sequences – mutations will not mess up protein production- and they frequently vary in length and thus reveal relationships among organisms. 

A few weeks ago, before this study was published, 2 species of flying squirrels were considered to exist in North America, the northern and the southern flying squirrel. Here in Ohio the northern flying squirrels is resident – it is nocturnal though, that’s why you probably have not seen one yet.

Map showing distribution of now 3 species of flying squirrels

Map showing distribution of now 3 species of flying squirrels

DNA analysis showed that the coastal squirrels in Washington and Oregon are distinct from their northerly relatives and that they actually only co-occur with them at 3 sites in the Pacific Northwest. Northern and the newly described Humboldt’s flying squirrel do not interbreed at these sites. By the way, the researchers named the new species Glaucomys oregonensis because the specimen that was used to describe the species was collected in Oregon.

You may recall from a previous post, that Dr. Andreas Chavez in our department of EEOB studies relationships among squirrels in a different genus, Tamiasciurus, the red squirrel T. hudsonicus and the Douglas squirrel T. douglasii. These two species share habitat in the Pacific Northwest and they do hybridize.

Dr. Chavez was not available for an interview for his thoughts on the new species description of flying squirrels, because he is currently pursuing his own fieldwork in the Pacific Northwest. He and his field assistant Stephanie Malinich are collecting data to better understand the hybrid zone dynamics between the Douglas and red squirrel.

We will give you an update on Dr. Chavez’ research once he returns.

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and writing this post for Stephanie Malinich, collection manager of the tetrapods collection. Stephanie is currently doing fieldwork on the red and the Douglas squirrel in the Pacific Northwest.

A gull look-alike

Another seabird species that I found to breed in Ireland is the Northern Fulmar Fulmarus glacialis. In a fleeting glimpse this bird may look like a gull but a closer look quickly reveals that is a close relative of albatrosses and shearwaters, the tubenoses Procellariiformes.

Can you see how this group of birds, the tubnoses, got its name? Doesn’t it look like they have a tube on top of their bill? This tubular nasal passage is used for olfaction. Yes, some birds do have the ability to smell. Especially seabirds use this sense to locate flocks of krill, shrimp-like animals that feed on single-celled marine plants (phytoplankton) right below the ocean’s surface. Breaking up phytoplankton cells releases a chemical called dimethylsulfide that concentrates in the air above areas where phytoplankton and thus krill are abundant. Researchers suspect that seabirds may smell their prey.

An acute sense of smell may also aid these birds to locate their nest within a breeding colony – you may recall the dense breeding conditions on the coastal cliffs from Monday’s post.

Furthermore, at the base of their bill these true seabirds have a gland that helps them excrete excess salt as they drink seawater. These birds and their relatives often spend long times out over the ocean without any land in sight. Thus they depend on drinking seawater.

So what do Northern Fulmars sound like? They are especially vocal when they return to their partner on the nest, they engage in an often minutes-lasting greeting ceremony. Listen to this pair recorded by Gabriel Leite in Clare county, Ireland (XC372370):

The unique morphological characteristics make these birds well adapted to their preferred environment of the northern oceans. They are among the longest-lived birds known, researchers estimate an average lifespan of 32 years for the Northern Fulmar.

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and currently teaches at the Audubon summer camp on Hog Island, ME.

 

Songs on both sides of the Atlantic

Like every year I will leave for Hog Island, Maine tomorrow morning. I will teach at two of the Audubon summer camps that have been held on the island almost every summer since 1936. You may recall this from my previous post.

This year I am particularly excited to watch birds along the Atlantic coast as I just returned from a trip to Ireland, on the other side of the Atlantic ocean. There I spotted birds of several species that also occur along the US coast. I doubt that the birds themselves make the crossing, but members of their species reside and breed on both sides of the Atlantic.

Rathlin Island

So which birds are we talking about? In Europe we visited Rathlin island, a small island off the coast of Northern Ireland, where we watched Atlantic Puffins Fratercula arctica, Razorbills Alca torda and Common Murres Uria aalge – or Common Guillemot as they are referred to in the UK. The Royal Society for the Protection of Birds (RSPB) runs a seabird center along the cliffs of the island where volunteers and staff regularly survey the breeding colonies and answer visitors’ questions. The resident naturalist shared with us the latest numbers: they estimate 100,000 Common Murres to breed on the cliffs, with them 20,000 Razorbills and some 700 pairs of Atlantic Puffins, everyone’s favorite due to their colorful breeding plumage.

Two Atlantic Puffins on Eastern Egg Rock

Atlantic Puffin on Eastern Egg Rock

On the US side of the Atlantic, in Maine, some 550 breeding pairs of these colorful seabirds have been reported in the largest colony on Seal island, ME.

Enjoy some photos of the Irish coastal scenery – I wish my photos conveyed the noise and smell that comes with large seabird colonies like these … David Attenborough in his Life of Birds series refers to these breeding conditions as the” slums in the bird world”.

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Most of these seabirds are not known for their vocalizations (although Black Guillemots may be exceptional with their distinct whistle; you can hear some in the background of the puffin recording below). Here are some recordings that I found in our collection:

Doug Nelson recorded this Atlantic Puffin on Matinicus Rock, Knox county, Maine, USA on 3 June 1981 (BLB23883):

Lang Elliott recorded a Common Murre on water near the Gaspesie Provincial Park, Bonaventure Island, Quebec, Canada on 1 July 1989 (BLB17181):

Common Eider is another bird that breeds on both sides of the Atlantic. Hear some nestling calls recorded by Don Borror on Eastern Egg Rock, Muscongus Bay, Knox county, Maine, USA on 23 June 1958 (BLB3508):

As you can see, most of these recordings were made a long time ago; time to go back and get some more recent recordings!

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and team-teaches at the Audubon summer camp on Hog Island, ME.

An 1892 Framed Plant Mount on display at the Thompson Library

The first director of The Ohio State University Herbarium and his wife, Dr. and Mrs. William Ashbrook Kellerman, prepared quite a large number of framed mounts of Ohio plants in 1892. According to the previous curator of the herbarium, Dr. Ronald L. Stuckey, these were “part of an exhibit of the Ohio flora displayed in the Ohio State Building … at the Columbian World’s Fair in Chicago in 1893. The total collection consisted of a display of mounted specimens of leaves, twigs, flowers, fruits, section of wood and bark of Ohio’s forest trees, and flowering plants, mosses, lichens, and algae.”

One of these framed mounts, twigs and wood section of the white oak tree, Quercus alba L., is currently on display at the Thompson Library until May 14, 2017. Dr. Florian Diekmann, head of the Food, Agricultural, and Environmental Sciences Library and Student Success Center, was in contact with the staff of the OSU herbarium early June last year seeking help in displaying specimens of white oak as many of the wooden structures of the main library were obtained from that plant.

Since the original twigs and leaves were not in good condition and the glass was chipped in a corner, Dr. Diekmann agreed to have it restored and refurbished. This is just one of the many framed, mounted but not displayed items in the Herbarium hitherto. The idea behind the gallery is to show the “unique connections and history shared between The Ohio State University and Ohio’s forests.” The Ohio State University Herbarium was glad to share its resources with the general public and has also made other items available for display at the gallery.

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Mesfin Tadesse, curator OSU herbariumAbout the Author: Mesfin Tadesse is curator of vascular plants at The Ohio State University Herbarium.

*** We would like to hear from you, please leave a comment ***

Flight of the Butterfly

What does re-animated life in the Triplehorn insect collection look like? What if a butterfly took flight from its drawer? Watch for yourself: Flight of the Butterfly by Tamara Sabbagh

THANK YOU Luciana Musetti, curator of the OSU Triplehorn Insect collection for facilitating the students’ visit.

About the Author: Angelika Nelson is the outreach and multi-media coordinator at the Museum of Biological Diversity and facilitates visits of school classes and students.

*** Which of the animations is your favorite? ***