Observations on the psyllids of southeast Arizona, August 20-26 2017

I attended the 2017 iNat-athon in Southeast Arizona with the intention to photograph as much of everything as possible, as well as to simply enjoy my first adventure into Arizona with like-minded individuals. However, another main goal was to seek out and document as much of the psyllid diversity as I could, and hopefully find some of the endemic species. With 70 species recorded, Arizona is the 3rd most species-rich state for psyllid diversity in the US, and about a quarter of those species have been recorded nowhere else in the world. Here are the species we found over the course of the week:

1. Heteropsylla texana - Mesquite Psyllid

On the morning of August 20th, our group set out from Tucson toward the Chiricahuas, making a stop along the way at Texas Canyon Rest Area near the Dragoon Mountains. Noticing several types of Mesquite trees (Prosopis sp.) growing at this location, I quickly scoped them out for psyllids and was able to find Heteropsylla texana, the most common of the southwestern mesquite psyllids. Nymphs were especially common on the stems of the new growth, and a handful of adults were found as well without much difficulty.

Photo © James Bailey

While mesquite trees were not uncommon throughout the rest of the trip, this psyllid was surprisingly absent from many locations later on in the week.

2. Nyctiphalerus propinquus - a Ceanothus Psyllid

In California where Ceanothus is particularly diversified, there are about a dozen known species of psyllids that specialize on the genus. Arizona on the other hand, which only has about 4 Ceanothus species to California's ~50, only has 3 known species of Ceanothus-feeders. While two of those are widespread western species, the third, Nyctiphalerus propinquus, is a southwestern Arizona specialty.

Flowering Ceanothus fendleri shrubs grew along side the road at several points in the Chiricahuas, and at a road stop near Onion Saddle I was able to find adult Nyctiphalerus propinquus often resting on the tops of new leaves, one per leaf. I found more at another stop along the same road the next day, and again on the same host in the Santa Catalina Mountains on the 26th. No nymphs, and no other species of Ceanothus psyllid, were found at any of these locations.

Photo © Chris Mallory

This marks the first time this species has been photographed. It is similar to related Californian species such as Nyctiphalerus vermiculosus and N. jugovenosus, but with the wings noticeably rhomboidal instead of broadly rounded.

3. Cacopsylla insignita - a Mountain Mahogany Psyllid

In Western North America, Cercocarpus is one of the most commonly used psyllid hosts, with about 14 species in four genera recorded from the plant. Most of these species are known only from either California or Utah, with very few species recorded from other western states where Cercocarpus is known to grow. I have speculated that this disparity is more likely the product of collection bias in those states rather than a real difference in biodiversity, so going into Arizona I was interested to see what species we could find on this host. Only one species, Cacopsylla brevistigmata, had been previously recorded from the state, but last August @alice_abela photographed a related species, Cacopsylla insignita, in southeastern Arizona. Adults of these two species are exceedingly similar, differing mostly in the relative length of the genal cones. But based on observations made in the past year by both Alice and myself, it is obvious that the two species differ in one very important way: nymphs of C. insignita induce leaf-curl galls on its host, while C. brevistigmata nymphs do not. Driving through the Chiricahuas, @silversea_starsong noticed Cercocarpus growing alongside the road, and so we got out to investigate. Quickly we noticed that many of the leaves were deformed as is typical of C. insignita, and sure enough we were able to beat adult C. insignita from all of the trees we checked and we were able to find nymphs inside of the galls.

Photo © Chris Mallory

Photo © James Bailey

Photo © James Bailey

A day after the iNat-athon had ended @berkshirenaturalist found this species in New Mexico, which is to my knowledge a state record. This further suggests that this species is more widespread in the west than it's currently known to be.

4. Bactericera minuta - a Willow Psyllid

More psyllid species use willows (Salix) in North America than any other host, with most known diversity in the west. Many of these species, especially those in the genus Cacopsylla, emerge very early in the spring before migrating to other plants (typically conifers) later in the season, only to return to their willow hosts in March to breed. As such, I didn't expect to find any willow-feeding Cacopsylla species in late August. However, willow-feeding psyllids in the genus Bactericera may be found on their hosts throughout the year, and at East Turkey Creek in the Chiricahuas I was able to find both adults and nymphs of Bactericera minuta on Salix gooddingii, a host which this species seems to prefer.

Photo © James Bailey

5. Kuwayama medicaginis

Kuwayama medicaginis is an interesting species in several ways. Found throughout the southwest, it is the only member of its genus that extends into the United States, with its congeners being primarily neotropical. Most South American Kuwayama are associated with Asteraceae, but K. medicaginis - as its name alludes to - was described from alfalfa, Medicago sativa. What's problematic here is that nymphs of this often abundant species have never been taken on Medicago sativa - or any other plant - and it wouldn't make sense for a new world genus of psyllids to breed on a plant native to Europe. In the years since its description, adults of this species have been taken from numerous unrelated plants, often in large numbers, but until the nymphs are discovered its true host will remain a mystery.

A potential lead was made last year when Salvador Vitanza collected a large number of adults from Atriplex canescens in New Mexico, and as such this plant became a target in the search for nymphs to hopefully confirm this psyllid's host. In the Chiricahuas, this plant typically grows at elevations between 4000-6000 feet. But no Atriplex of any kind was around at Barfoot Meadow, where, at an elevation over 8000 feet, I swept one adult male Kuwayama medicaginis from low vegetation. I was unable to produce any other adults or nymphs from the plants in the area, though, so unfortunately the origin of this psyllid will continue to remain a mystery. But we now know that Kuwayama medicaginis definitely occurs in the Chiricahuas, and more sampling in the area may eventually reveal the life history of this insect first described over a century ago.

Photo © Chris Mallory

6. Pachypsylla celtidisvesiculum - Hackberry Blister Gall Psyllid

7. Pachypsylla venusta - Hackberry Petiole Gall Psyllid

8. Pachypsylla pallida - Hairy Bud Gall Psyllid

9. Tetragonocephala flava - Sugarberry Psyllid

Hackberry psyllids are the most commonly recorded psyllids in North America, in large part due to the very conspicuous galls that most species induce on their hackberry hosts. Each Pachypsylla species specializes in making a certain type of gall on a particular part of the plant, with different species using the stems, the buds, the petioles, and the leaves. In Arizona, there are three hackberry gall psyllids that can be expected. The blister gall psyllid (P. celtidisvesiculum) and petiole gall psyllid (P. venusta), both widespread North American species, find their natural western limit in the state. They are joined by the hairy bud gall psyllid (P. pallida), an uncommon southwestern specialty. Additionally, Tetragonocephala flava, a related species, does not create galls but the nymphs instead construct protective sugary lerps on hackberry leaves.

Just outside Portal Peak lodge, @silversea_starsong found one hackberry tree where all four of these species were present. Galls of all 3 Pachypsylla species were common, with nymphs found in each gall type. While P. venusta and P. pallida adults don't emerge until much later in the year, adult P. celtidisvesiculum were beginning to appear, with @berkshirenaturalist documenting one such teneral adult that had yet to develop its characteristic maculation. Tetragonocephala flava lerps were present on the leaves, but empty; given that Salvador Vitanza photographed adults of this species one month prior in Nogales, it's likely that if given more time we may have been able to find adults here as well.

Pachypsylla celtidisvesiculum adult. Photo © James Bailey

Pachypsylla celtidisvesiculum teneral adult. Photo © Jason M. Crockwell

Pachypsylla celtidisvesiculum galls. Photo © Chris Mallory

Pachypsylla pallida gall. Photo © Jason M. Crockwell

Pachypsylla venusta gall. Photo © Jason M. Crockwell

Tetragonocephala flava lerp. Photo © Jason M. Crockwell

10. Calophya minuta - a Sumac Psyllid

Psyllids in the genus Calophya are found throughout North America, with each psyllid specific to a particular species (or group of species) of Rhus (sumacs). The widespread Rhus aromatica, for example, is a common host, particularly for the equally widespread C. triozomima. But while Rhus aromatica was indeed plentiful in many places of the places we explored, there was almost no psyllid activity found on this host. My target psyllid species was Calophya minuta, a southeast Arizona endemic, never before photographed and only known from "Rhus sp." Which Rhus in particular, however, had never been recorded, so I made a point to check every type of Rhus I encountered.

I first ran into Rhus virens in the Huachucas, and near Eighty Spring on Montezuma Canyon Road I was able to check this potential host for psyllids. That investigation proved successful, and I found several adult Calophya minuta. Rhus virens became a priority after that discovery, and two days later at Peña Blanca Lake I found one particular Rhus virens shrub covered in dozens of adult pairs. Closer inspection revealed the presence of the nymphs on the fruits, and tiny black eggs all over the leaves, confirming R. virens as a host for this species.

Photo © Jason M. Crockwell

11. Aphalaroida inermis - a Mesquite Psyllid

Aphalaroida is a small southwestern genus associated with Mimosoid legumes, especially mesquite. While mesquite was common everywhere, it wasn't until the 24th at Peña Blanca lake that we found our first (and only) member of this genus that is represented by 5 species in Arizona. While many Aphalaroida are easily recognized by the glandular hairs that cover the head, thorax, and wings (such as in Salvador Vitanza's photo here of A. spinifera), A. inermis is one of the several species that lack such hairs.

Photo © Jason M. Crockwell

12. Cacopsylla sp. - a Purshia Psyllid

As the sun began to set on our final day in Arizona, we found ourselves at a rest stop along Mount Lemmon Highway, waiting out the storms that were starting to roll in before deciding our next course of action. It was here that James noticed that one of the shrubs at this stop - some type of Purshia sp. - was crawling with psyllids! While about 5 different psyllids are known from Purshia tridentata, this was another species of Purshia, and therefore an unrecorded psyllid host. Recognizing this, I collected several males for future study - I hope to determine soon whether this is one of the known Purshia tridentata associates, or if it is a related but undescribed species that specializes on a related host. Either way, an exciting find!

Photo © Jason M. Crockwell

13. Heteropsylla sp. - an Acacia Psyllid

Psyllids are tiny, and they can be easy to miss even when you're looking for them. As such, it wasn't until after the iNat-athon had ended that James noticed some psyllids on Acacia angustissima in the background of other photos from Peña Blanca lake. These psyllids can be recognized as some kind of Heteropsylla, but not the maculate-winged H. texana mentioned above. The mostly-neotropical genus is very large with many similar species of Mimosoid legume feeders, and there are probably more species in the US than are currently known, especially in southern Arizona and Texas. Two species in particular have been recorded from Acacia angustissima, though both are currently known only from Panama to southern Mexico. This species will definitely be a target the next time I visit Arizona, and hopefully then we can understand its identity.

Photo © James Bailey

Overall, I'm rather impressed with everything we were able to find in just one week! Many thanks to @finatic and @jaykeller for organizing the trip, and to everyone else that was a part of it that made it great. It was wonderful meeting everyone and I'd love to return soon!
הועלה ב-אוקטובר 12, 2017 06:57 אחה"צ על ידי psyllidhipster psyllidhipster


Excellent write-up, Chris! And magnificent photographs too. :)

פורסם על-ידי sambiology לפני יותר מ 6 שנים

Thanks Sam! All credit to Jason and James for most of the better photos I used in this post.

פורסם על-ידי psyllidhipster לפני יותר מ 6 שנים

Chris, it was great spending some time out in the field with you. I have a new appreciation for these insects and am in awe of those of you that can find such tiny little critters. Let's do it again some time soon.

פורסם על-ידי finatic לפני יותר מ 6 שנים

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