Sunday, August 5, 2018

Longhorn and Jewel Beetles at Portal, Arizona

Many of my bug safaris are just naturalists' explorations of anything crawling or buzzing around or hiding under cow dung. At other times, the participants concentrate on a certain family of insects, which helps my blog writing tremendously. This focus may develop inadvertently because habitat, season or a weather event favors the appearance of certain groups of insects.  Or it develops because my excursion companion arrives with an interest in certain taxonomic groups, and we seek out habitat that supports those groups. Hopefully weather patterns and moon phase don't work against us. For several weeks now, I joined the Arizona tour of my friend and co-author for the book Arizona Beetles, Dr Arthur Evans. We looked for all kinds of beetle species in places that Art already fondly remembered from the past and a few that I introduced him to. At the same time we hoped for more monsoon activity.  On the last July weekend, the arrival of Ted MacRae made us concentrate somewhat more on his favorite groups, Cerambycids and most of all Buprestids. We all met in the Southfork Creek area near Portal in the Chiricahuas. In Portal I always enjoy the lovely hospitality of my friend Barabara Roth, definitely a great added bonus to the breathtaking beauty and the ecological richness of the area.

Many Cerambycids are night-active forest creatures and come to black lights quite willingly. Of course they have been much more active in wetter years, and I had many more species at my lights then. This year I strung my light's out in Barbara's back yard.

There, Ted and Art also found a very small Hardwood Stump borer that may have emerged from a cavity riddled stump, left in place from a tree that died,  and that is now part of Barbara's entrance steps.

Styloxus bicolor, a cerambycid with short elytra. From Barabara's place in Portal. Photo Steve Lingafelter
Tetraopes discoideus
Rhopalophora meeskei and Lycids
Tetraopes femoratus
Luckily the Southwest Research station further up Southfork Creek Canyon uses its leach field to create a wet meadow with an abundance of Narrow Leaf Milkweed. There we found at least  2 more species of Cerambycids, and I am adding here the larger Tetraopes femuratus that I have found in that location a couple of years ago.Tetraopes means Four-eyes, and in the portrait you see what that name points to.

Ericydeus lautus, my personal rain weevil
I used my big beating sheet to find out what's hiding in shrubbery along Sunny Flats CG. One beat delivered dozens of cm long grey weevils into the sheet and I knew immediately that the monsoon would get serious that afternoon: when these weevils climb vegetation in big numbers they are trying to stay away from serious flooding.

Mwcas rotundicollis
We discovered a couple more Longhorn species along the trail from Steward to Sunny Flat Campground, visually by gleaning grasses and leaves like a warbler would. It's my favorite collection method because I learn more about behavior and host plants and I can often take in situ photos. Though that tendency can easily result in the loss of a rarely encountered bug. As many beetles first drop and then fly, I held my sheet under the mysterious Acanthocine that is still unidentified. The more formal photo on white with better lighting shows more detail, for example the pronotal thorns that  indicate that it's not for example Pseudastylopsis  but rather Sternidius or another 'armed' genus.

Far more flighty and shy than the morning-sluggish Cerambycids are the Buprestids. Tiny  Pachyschelus secedens is the exception, usually clinging tightly to its legum host Desmodium.

On the soft, sunflower-like leaves of an as yet unidentified Asteraceae we found, as I had expected,  a number of red-necked Agrilus. There are 2 similar spp. around in SE AZ, so I have to wait for Ted to work on the exact identification.  A few Acmaeodera cazieri turned up on the very few flowering plants at Sunny Flats and along the road.

Leptinotarsa rubiginosa, arguably the prettiest of the 'Potato Beetles' diverted even Ted's intense buprestid-focus for a while.  The bright red bug really screams for attention, but I have never found more than a single one and never on its supposed host plant the ground cherry.

Leptinotarsa rubiginosa
After the pleasant canyon hike along the dry creek, always towards some threatening, grumbling clouds just beyond the towering cliffs, we moved out into the flats between Portal and Rodeo. Ted knew records of  Sphaerobothris ulkei (LeConte) on Mormon Tea plants Ephedra trifurca.  It grows among rather low scrubby Mesquite Trees and Sweet Acacias, some of which were blooming. But everything else, including the Ephedra bushes, seemed dried out and barely alive. The heat was quite oppressive in those open flats.

Desert flats below Portal, Arizona – dominant woody vegetation is mesquite (Prosopis glandulosa), sweet acacia (Acacia rigida), and three-pronged joint-fir (Ephedra trifurca). Photo and description Ted MacRae
Still, sudden buzzing noises announced some rather active beetles: big Hippomelas males and even larger females  were zipping around those   knee-high mesquites.

Hippomelas shenicus
 From Santa Ritas I am quite familiar with Hippomelas planicaudata. Especially in the evening, I often see dozens of them on the pink blooming Mimosa. They are blueish grey with a yellow wax exudant. The Hippomelas at Portal were larger, more brassy in color and the exudant was orange: Hippomelas sphenicus (above).  Compare to H. planicauda from Florida Canyon, Santa Rita Mnts, below

Hippomelas planicauda

Acmaeodera gibbula were sitting on flowers and branches of the one blooming Acacia rigida

These Acacias are also the host plant of the large large, yellow powdered Gyascutus caelatus, and Ted and Art found a few of those, too.

Gyascutus caelatus
But our target species was hard to find, until Art spotted the first two Sphaerobothris ulkei  running in their characteristic bursts of speed on the stems of a good-sized Ephedra plant. The beetles were a shiny, metallic blueish green, chunky and nearly a cm long. They actually stood out from the leaf-less grey-green plant branches to be visible from several meters distance. But I was also spotted easily by these highly visual creatures, so it still took me a long time to catch one female of my own.

Sphaerobothris ulkei
 I missed the first one because I tried to photograph her in situ. I learned that  they easily fly off when discovered, but land predictably on the next nearest Ephedra bush. They zoom right towards this target, even when it is hidden behind  dense taller vegetation. So I figured out how to find them again and followed. Hunting these beautiful beetles was very exhausting even though the area was flat. The upcoming thunderstorm made the air oppressive and hard to breathe. After our hunt we were happy to retreat to Barbara's living room to photograph our beetles

Sphaerobothris ulkei female

Art and Ted at work
And the rain storm that the 'rain' weevils had announced? Just before dinner at the South West Research Station, it hit the Southfork Creek area. When after dinner Art and Ted wanted to cross a wash on Foothills Rd they were stopped by racing water. Surprisingly, at Barbara's house the creek showed not even a trickle.

Minor flash flood and easterner, easily impressed

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