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I will use this album to post updates of my website as new material becomes available, and before it can be incorporated into the website itself. For instance, I collected this Laphria sp. in June 2008 in the middle of a ten-acre lespedeza field in Baxter County on the edge of Norfork Lake. So far, the identification is still being determined.

In the field it looked like a small (11.6 mm) Laphria sicula (which see), except some sort of marking could just be seen on the abdomen. Under a microscope (and in this blown-up photo), the marking is revealed as appressed golden hairs on the last few segments. It appears that this is an undescribed species.

For years we have been catching glimpses of an Ommatius which doesn't have the leg-marking of O. gemma or O. ouachitensis, the only species so far recorded in Arkansas. Here is a picture we managed to get of it on Crowley's Ridge in 2008. Note that the hind femur is over fifty percent black, and the entire middle femur is black on its leading edge. Last year (2009) Edward Trammel collected a male marked like this in NW Arkansas, and Jeff Barnes examined it and said it was either an undescribed species, or a western species we have no key for. Either way, it constitutes a new species for the state.

Now this year (6/5/10) I have caught several fresh males in Jonesboro, Craighead County. Ommatius are all so similar to each other that usually for identification purposes the male genitalia must be examined under the microscope. Here is the tail end of a typical O. ouachitensis. Note the more or less blunt paddle shapes extending from the end.

Now here is the hind end of the unidentified Ommatius. Note how the paddles pinch down to a sharp point, like the nib of a pen. It is this different shape that strongly suggests we are looking at an undescribed species. This will need to be studied further.

In 2010 I caught several males from Craighead Co. and deposited them in the Arthropod Museum at Fayetteville. This year on 6/19/2011 I photographed this individual at Camp Robinson in Faulkner Co. north of Little Rock. It is particularly well-marked, showing the leading edge of the fore and mid-femora entirely black, and the hind femora almost entirely black. So these dark-legged Ommatius have so far been found in NW, NE, and now Central Arkansas.

Here is another well marked example, this one from 5/27/12.

In 2009 I realized I was looking at a dark Proctacanthus species I had never seen before. I collected it, and it became the first record of P. nigriventris for Arkansas. Now recently I was looking through some old pictures I had taken of Proctacanthus milbertii in Greene County and saw that this one, taken in 2008, in fact is also P. nigriventris, which I had totally overlooked. Note the black marking on the thorax (brown marking in milberti), sooty black femora (paler in milbertii), and, except for the pale terminal segment, the abdomen is black with distinct pale bands

Here is another picture of Protacanthus nigriventris, taken in the same area, this time in late October 2011. I crouched down low enough so that I could catch a glimpse of the black abdomen, without having to look through the wings.

We just visited the arthropod museum in Fayetteville (2/22/10), and while looking through the specimen trays, made some discoveries. First, this picture in my web site which I called Laphria index is in fact the look-alike species Laphria ithypyga. All the specimens I had taken in the past from the NE corner of Arkansas are that species.

Here for comparison is Laphria index on the left, and L. ithypyga on the right. It is clear that at least the males are distinguishable in the field, index with large bulbous genitalia, ithypyga much more modest. Also, and quite visible in this picture, but probably not in the field, index has two blunt apical processes on the last segment of the abdomen, which ithypyga does not have.

This male I saw on the western side of the state is clearly referable to Laphria index.

Here is a pair of L. index from the western edge of the state (the female is eating a bee). Evidently index does not occur on Crowley's Ridge, though I will need to check that this year. I'm glad to get these two straightened out finally.

Here is an important addition to Other Arkansas Robber Flies. This is Zabrops flavipilis, a close relative of Laphystia and Psilocurus. Herschel Raney collected an individual of this species 5 July 2005 in Pope County, and until now that has been the only Arkansas record for this rare robber fly. I collected an individual 29 June 2010 in eastern Mississippi County, and returned 30 June to get these live photos, perhaps the first ever taken of this species.

These were in dense tall weeds on the edge of riparian woods along the Mississippi River in the NE corner of Arkansas. They are so close to being in the designated area of my website that I will now look for them in appropriate habitat on Crowley's Ridge. They are small (10-12 mm) and look rather like Psilocurus birdi (which see), except they are darker and obviously covered with long yellow hair.

Here is another addition to Other Arkansas Robber Flies. This is a male Efferia texana. I found a group of these 8/1/12 in a pine barren in Hot Springs Village, in Perry County.

Efferia texana, female, Hot Springs Village

Here is another addition to Other Arkansas Robber Flies. This is Stichopogon colei, a very small robber that is found on white sandy beaches along the Arkansas River. We found this example at Choctaw Island, Desha County, a few miles south of where the Arkansas River enters the Mississippi River.

This is Asilus sericeus, in the namesake genus of the family as a whole: Asilidae, the Robber Flies. The standard arrangement of subfamilies and species I used in my website has long been known to be flawed and provisional because lacking rigorous phylogenetic analyses. Now T. Dikow has published two papers, both in 2009, one a morphological, one a molecular, study of the relationships of Asilids, the most thorough studies yet, and there are a number of changes.

A common ancestor gave rise to the flower-loving flies and the mydas flies, who went off in their direction, and to the Asilids who went in theirs. That first Asilid line (according to Dikow's molecular study), led directly into what is now the subfamily Trigonomiminae (which see), of which our local representative is the genus Holcocephala. Here is H. calva eating a small fly.

A split off the Trigonomiminae became the Laphriinae (which see). This subfamily still retains the largest number of ancestral traits of any robber fly group, and in fact in Dikow's morphological study it is the Laphriinae which came out as the basal line from which all the other robber flies derived (Dikow claims there is not enough evidence to prove conclusively which is correct). Laphria is the best known genus in the group (this is L. affinis).

Others in the subfamily are Atomosia and Cerotainia (this is C. albipilosa).

Also Lampria (this is L. rubriventris), Orthogonis, and Pogonosoma.

A change is that the subfamily Laphystiinae (which see) has been collapsed, and its members Laphystia and Psilocurus (this is P. nudiusculus) are now brought into the Laphriinae

as is also Zabrops flavipilis.

A branch off the Laphriinae gave rise to all the other subfamilies of robber flies. This first of them is the Dasypogoninae (which see), of which our only local representative is the genus Diogmites (this is D. angustipennis). Nicocles was formerly located here also, but it has now been placed in a new subfamily.

The new subfamily is the Brachyrhopalinae. It was known that the subfamily Stenopogoninae (which see) was a catch-all group of unrelated genera waiting to be placed somewhere. Now many of the old Stenopogoninae and Dasypogoninae have been placed here. For example, here is Nicocles pictus in its new home.

Among the old Stenopogoninae genera now in Brachyrhopalinae is Heteropogon (here is H. macerinus, which I always thought looked and behaved a lot like Nicocles, so I am happy to see them finally together).

Also included in Brachyrhopalenae: Holopogon (this is Holopogon phaeonotus), Ceraturgus, and Hadrokolos.

Another refugee from Stenopogoninae is now in its own subfamily, Dioctriinae, including Echthodopa (here, Echthodopa formosa) and Eudioctria.

A few have remained in Stenopogoninae, including this big Microstylum morosum

and also Prolepsis tristis (this is the female, a mimic of Polistes wasps).

The old Stichopogoninae has remained the same. Here is its best known member, Stichopogon trifasciatus.

And still in the subfamily is the tiny Townsendia nigra. Lasiopogon is also a member.

A very big surprise is to find the Leptogastrinae this late in the list (this is Psilonyx annulatus. Other genera in the group are Apachekolos, Leptogaster, and Tipulogaster). Before Dikow's study, Leptogastrinae (which see) was thought to be the ancestor of all the robber flies. Indeed, some had placed it in its own family before the Asilidae. But it turns out it is a derived group "deep" in the family, in fact close to the Asilinae and Ommatiinae.

The next subfamily in the old system, the Apocleinae (which see), has vanished, and all of its members have been moved up into the now very large subfamily, the Asilinae. That includes the genus Efferia (this big Efferia nemoralis has cottonwood fluff on its back suggesting its riparian habitat), as well as Mallophora and Megaphorus.

Also in the new subfamily Asilinae are Promachus (this is Promachus hinei)

and Proctacanthus (this is Proctacanthus hinei, but in an especially dark almost black form, which we occasionally get in northeast Arkansas).

Here is a more normally pigmented Proctacanthus hinei.

All of those are now combined with the original members of the Asilinae (which see), which include Asilus sericeus (its picture was at the beginning of this sequence), and Neoitamus (this is a Neoitamus flavofemoratus female), as well as Dicropaltum, Philonicus, and Neomochtherus.

Also the large Genus Machimus (this is M. snowii).

And finally the subfamily Ommatiinae (represented here by Ommatius ouachitensis) has remained the same, and has retained its position as being, evidently, the most derived group.

Speaking of Ommatius, I had long suspected the genus was crepuscular, but I had never tried to prove it. One was hanging around in our backyard and I had noticed it out in early evening and decided to keep an eye on it. The date was 7/5/10: "At 8:30 it is dark enough I cannot see my Ommatius, even with close-focusing binoculars, from more than six feet away. In this much light it flew up about six inches and returned to its post, and when I got very close I could see it had caught some tiny creature about the size of its head."

"At 8:45 I came out again (mosquitoes made it impossible to stay out) and I could just make out the Ommatius (through binoculars from about four feet away) in silhouette against the light-colored wall of my house. It was turning around alertly as a robber does when it is watching potential prey items fly by. Once a moth flew over its head, about ten inches above it, big enough so I could see it in the near-darkness, and the Ommatius flew up part way towards it, though it was way bigger than anything it would normally chase. "I came out at 8:50 with a flashlight. It was gone."

Here is a rather interesting finding by a friend of mine. This is the all-black male of Microstylum morosum (ten pictures back in this album is a picture of the reddish female). Look in the website under "Other Arkansas Robber Flies" for details of this very big, dramatic robber. It is strictly a prairie species found in Texas and Oklahoma, but with a handful of records in extreme southwest Arkansas (in prairie or prairie-like regions). But this one was found (August 2010) freshly dead in Baxter County, on the eastern shore of Lake Norfork, in a wooded area near the Missouri border. I guess a big powerful animal like this can fly wherever he wants to.

And now (July 16, 2012) Cheryl and I have found this female Microstylum morosum even farther to the northeast, in Sharp Co., and in even denser woods, on a gravel road through upland deciduous forest in the Harold Alexander WMA. So is the species less tied to prairie habitat than we have always assumed?

Here is the cover of the November 2010 Birding magazine showing a Proctacanthus rufus in the lower right-hand corner. This issue contains my article "The Next Recreational Insects?" in which I argue that, following butterflies and dragonflies which birders are beginning to enjoy watching in addition to birds, perhaps robber flies might be an appropriate next group of insects to take up.

Here is a problem I am currently working on. This robber fly keys to Machimus snowii. It emerges in late July and flies through August and September. I find it over dried mud or silt in seeps and swamp overflow areas, often more or less shaded by trees, where it feeds largely on moths. As this picture shows, in the camera's flash, it has a distinctly golden color.

But as many commentators have noticed, a robber fly also keying to Machimus snowii emerges and flies for a brief period in June. This one is found on sandy soil in slightly higher ground than the previous individual (the early and the late populations are in locations far removed from each other). It does not have a golden cast, and the male appears to me to have larger and chunkier genitalia.

I think the early population (on the right), may be a different, unnamed species.

As appendices to my website "The Robber Flies of Crowley's Ridge" I had already added "101 Butterflies of Crowley's Ridge," and "The Tiger Beetles of Crowley's Ridge." For anyone who may be interested, I have now added seven more albums: First: "The Dragonflies of Crowley's Ridge," which has images of 54 of the 60 species that have so far been recorded on Crowley's Ridge. http://picasaweb.google.com/norman.lavers/TheDragonFliesOfCrowleySRidge#

Next: "Argiope and Argyrodes," where I have illustrated life histories of the big Argiope Garden Spider, and the tiny silvery Argyrodes, which live parasitically in Argiope's web. http://picasaweb.google.com/norman.lavers/ArgiopeAndArgyrodes#