Guide to Cactus Spring Trail Butterflies
Updated Oct. 23rd, 2023
|Papilio polyxenes rudkini
|Thamnosma montana (Rutaceae)
|The host, Turpentine Broom, is common along the trail and the butterfly is a regular here. Saw several hilltopping near the so-called Dolomite Mine on Feb. 9, 2023, and a female was flying October 21st of the same year, so they can fly much of the year.
|Possibly Prunus ilicifolia (Rosaceae), and/or Fraxinus velutina (Oleaceae) - Arizona ash tree.
|The largest butterfly on the trail, with a powerful flight.
|A citrus feeder, but I don't believe this is breeding on trail.
|I saw one fly by in the spring of 2020. No doubt a stray.
|I've seen females oviposit on Sisymbrium orientale and Descurainea pinnata here; there is no bladderpod, Peritoma arborea (Capparaceae), on this trail.
|Not uncommon in the spring. May use other mustards as well.
|They use a variety of mustards (Brassicaceae).
|Probably Descurainia pinnata ssp. glabra, as one that appeared to be ovipositing 4/5/15. Sisymbrium orientale also a good candidate.
|Pontia s. sisymbrii
|Descurainea pinnata ssp. glabra
|Early flyer. Found a larva on this plant in late April, 2017, and adults in March that year and the next. Common in April, 2019. In 2023, saw one Feb. 9th.
|Anthocharis s. sara
|I've seen the larvae on Descurainia pinnata ssp. glabra (Brassicaceae) not far from the trailhead. Watched one oviposit on Thysanocarpus laciniatus (narrow leaved lacepod) as well (4/23/17), and found several larvae on lacepod in April 2019.
|These typically fly from February into May, peaking Mar/April. In 2016, the Descurainia was senescent by mid-May, and the flight was nearly over.
|Anthocharis c. cethura
|Mustards, but time will tell which.
|First and only sightings by me were in early April, 2019.
|Anthocharis lanceolata desertolimbus
|Boechera perennans (Brassicaceae)
|This is a great trail to see this recently-described butterfly. My sightings have been late March and early April, usually with the adult taking nectar on Acmispon rigidus.
|Mainly Astragalus (Fabaceae), but rarely Acmispon glaber
|Astragalus douglasii (not on the trail) is the classic host, but the Monroes also list A. palmeri, which is the most common of the three rattlepod species here.
|Deerweed, rattlepod, poss. lupines.
|The Emmels (1973) have deerweed, and "possibly several Astragalus species". The Monroes list Astragalus crotalariae, Acmispon strigosus, A. glaber, and Lupinus bicolor. So there are many candidates on this trail.
|Saw one April 22, 2017. I think this was my only sighting of this butterfly on this particular trail to date. But not too surprising.
|Amorpha fruticosa (Fabaceae), a common plant on this trail.
|The abundant host, especially at drainages along the trail, is the reason there are so many of these flying here practically all year.
|Zerene c. cesonia
|Marina orcutti (Fabaceae) possibly? This rare plant is well down the trail (2.5+ miles) per Tom Chester's surveys. Maybe it uses Marina parryi, which is in the vicinity if not on the trail itself as far as we currently know.
|Not at all common, but may be found occasionally on the trail. This species hybridizes with eurydice, and I've photographed the F1 female that results from a male eurydice x female cesonia. Gordon Pratt sees it regularly in Anza.
|Many hosts. On this trail, probably Adenophyllum porophylloides (Asteraceae)(San Felipe Dyssodia).
|A very common butterfly most of the year. This is a beautiful, tiny sulphur with darker and lighter seasonal forms. Often patrols the trial, stopping on the dirt regularly. The Monroe's Anza-Borrego book has three hosts: San Felipe Dyssodia, Spanish Needle (Palafoxia arida), and Cinchweed (Pectis papposa). The latter two are not on the Chester list. I've searched in vain for larvae on the Dyssodia so far, but I found a chrysalis nearby. Note that this is the only Pierid we have that uses Aster family plants.
Hairstreaks and Blues
|Atlides halesus corcorani
|Uses mistletoe (Viscaceae), and there are three here: Phoradendron villosum, densum and califoricum, with the first two common on juniper and ceanothus. Eggs may be found on densum on juniper along the trail if you look carefully at the right time.
|Not common here, but it is present. An absolutely stunning large hairstreak with neon-like colors set against black. Always a treat to see, especially when fresh.
|Callophrys augustinus iroides
|Many hosts; I've recently seen them on Rhus ovata but they probably use Ceanothus perplexans (Rhamnaceae) as host here.
|Not as common here as they can be elsewhere. A spring flyer.
|Callophrys dumetorum perplexa
|Many, inc. buckwheats, deerweed, Ceanothus.
|They can be fairly common earlier in the spring around patches of Eriogonum fasciculatum not far from the trailhead parking area.
|Juniperus californica (Cupressaceae) is a dominant plant here.
|A featured flyer on this trail, it can be found conveniently right at the parking lot among the junipers to the north, as well as along the trail wherever there are junipers. The colors of this population on the ventral side can vary a bit, but typically (when fresh) they have plenty of blue and/or pink, while subspecies juniperaria, on the desert side of the San Gabriels, has more olive green. That said, I saw a very green one this spring (2016).
|Satyrium c. californica
|An Oak and Ceanothus feeder.
|Early summer flyer.
|Satyrium auretorum spadix
|Also early summer as an adult.
|Satyrium saepium chalcis
|Probably Ceanothus perplexans (Rhamnaceae)
|More common along the Santa Rosa Truck Trail a few miles to the west, but also usually present here if not common.
|Cercocarpus betuloides var. betuloides (Rosaceae)
|I've seen these in June and July along the Santa Rosa Truck Trail, but the host also is present on Cactus Spring Trail.
|Strymon istapa clenchi
|Hibiscus denudatus (Malvaceae), which isn't on the trail.
|Uncommon, but flying late March, 2014 and early April 2015.
|Strymon melinus pudicus
|Too many to list, but California Buckwheat is one.
|Not surprising to find them anywhere.
|Several hosts, including Senegalia greggii and Amorpha fruticosa (Fabaceae), and I see it commonly around these. But I've actually watched it oviposit on deerweed, so it may prefer that.
|A common garden butterfly that also thrives in the desert.
|In 2023, I finally confirmed that it uses Salsola tragus (Chenopodiaceae) near the trailhead. May use Amaranthus albus (Amaranthaceae).
|This handsome and diminutive butterfly may appear almost any time of the year on the trail.
|Celastrina e. echo
|Uses many common trees and shrubs, inc. Ceanothus, Oaks.
|I have only a couple of confirmed sightings of this butterfly here: in late April and May of 2017.
|Glaucopsyche lygdamus australis
|I've seen one oviposit on Acmispon rigidus (3/24/12), and it no doubt uses deerweed - A. glaber (Fabaceae) on this trail. Both are common right from the trailhead.
|An early spring flyer which can be common some years.
|Philotes s. sonorensis
|Host here must be Dudleya saxosa ssp. aloides (Crassulaceae)
|Another stunning and sought-after butterfly that can be found here in the spring, though perhaps not reliably. My records are from February through April.
|Euphilotes b. bernardino
|Eriogonum fasciculatum (Polygonaceae)
|Common butterfly that uses a common host. A spring flyer that can become abundant some years.
|Euphilotes dammersi dammersi
|Eriogonum wrightii vars membranaceum and nodosum (Polygonaceae)
|Fall only around the host buckwheat, which blooms at that time. Pratt and Emmel (1998, p.211) divide dammersi into three populations, one of which is a low desert group extending from the San Bernardino Mountains south into Mexico. (There is also a spring-flyer on the northeast side of the San Bernardinos on E. kennedyi or E. davidsonii, and a population in the Mojave.) A good place to see this blue in autumn is to check the patches of wrightii two-tenths of a mile from the trailhead, just before the trail signs at the road junction. Another is just short of the creek before the so-called "dolomite mine". The black spots on the underside have a characteristic "smudging" that is easy to see.
|Hemiargus ceraunus gyas
|Senegalia greggii (catclaw), Prosopis glandulosa (honey mesquite) and locoweeds such as Astragalus palmeri (Fabaceae). Will also use buckwheats.
|I saw a female ovipositing on Senegalia greggii buds on May 27, 2016.
|Hemiargus/Echinargus isola alce
|Senegalia greggii, Prosopis glandulosa (Fabaceae).
|Seen only occasionally on the trail. Mesquite is pretty far down the trail, but catclaw can be found about a half a mile along and is more common.
|Many in several families
|Found a larva on Eriogonum davidsonii on May 27, 2016.
|Eriogonum fasciculatum (Polygonaceae)
|This and the above taxon are part of an interesting complex. Both fly on this trail. I label many of them "acmon complex" if it isn't clear what's what. John Emmel considers monticola a full species (separate from lupini) and says they are "atypical" in this area.
|Bebbia juncea (Asteraceae)
|Not common at all here
|Apodemia v. virgulti
|Eriogonum fasciculatum (Polygonaceae)
|Common and multiple brooded, so may be found from spring to autumn. On this trail, there is phenotypic variety. Some males have little orange on the hind wing. Females are a noticably lighter color and larger than the males, some more than others.
|Milkweed, but probably doesn't breed here. See next entry.
|Danaus gilippus thersippus
|Funastrum crispum (Wavyleaf twinevine) is just off the trail not far from the trailhead; Bruce Watts showed it to me in 2023 and found more as well. It is in the Asclepiadaceae, as is Matelea parvifolia (Spearleaf), which was found a tenth of a mile shy of Horsethief Creek. I'm not sure whether this is used by Queens and/or Monarchs locally. So far, it seems that Queens aren't feeding on F. crispum here.
|A desert butterfly sometimes seen taking nectar here as at Horsethief Creek on the goldenrod.
|Chlosyne acastus neumoegeni
|Acamptopappus sphaerocephalus (goldenhead)
|Two seen patrolling approx. 2 miles down the trail on March 3, 2020. I'd never encountered this butterfly here before that year.
|Chlosyne leanira wrighti
|Castilleja foliolosa (Scrophulariaceae)
|Late spring flyer that may have a fall brood if conditions are right (saw one Sept. 20, 2014 after not seeing them that spring). I've seen larvae in mid-April as flight began, with adults through May. They are often well down the trail where the host is more common, but I've seen them hilltopping on the hill just past the Dolomite Mine. This striking butterfly may be absent (or nearly so) many years, and never seems to be common. Always good to see.
|Bahiopsis parishii (Asteraceae)
|Tom Chester's plant guide has the host beginning at 2.37 miles from the trailhead, but it also grows along the "alternate" old road that goes from the Dolomite Mine area to Sawmill Creek Road, near the top. The population of this butterfly seems to fluctuate, but it can be fairly common at Horsethief Creek some years on the Goldenrod there, and individuals can show up anywhere. In 2017, I was seeing it even in town in Palm Desert.
|I thought it was a stray, but I saw one ovipositing on Cordylanthus rigidus ssp. setiger on June 7, 2020 down the trail. Also on the trail is Plantago patagonica, or perhaps the local paintbrush spp.
|A brief sighting on June 3, 2017, and the one mentioned ovipositing three years later almost to the day.
|Microtia dymas imperialis
|The host, Justicia californica (Acanthaceae), isn't on the trail.
|I saw one September 20, 2013, and another April 5, 2015, but this trail is (probably) quite a ways from where the host Chuperosa is known to grow (online records have it several miles to the north and east). So add this to the list of unexpected sightings.
|Phyciodes m. mylitta
|The classic host is thistle (Cirsium species.
|A single sighting for me on this trail: May 18, 2012. Can be common elsewhere.
|Euphydryas chalcedona nr hennei
|Keckiella antirrhinoides var. microphylla (Plantaginaceae) confirmed on this trail. Brian Banker found a larva in 2023 on what I think was Cordylanthus rigidus.
|True hennei is named from Box Canyon in Anza-Borrego, and the chalcedona here tends to be lighter, possibly due to gene flow with corralensis to the north. Common, sometimes abundant, with a fall flight most years. I was surprised to see one on November 29th, 2022, a very late date. These will, at times, be your regular companion on a hike all the way down the trail to Horsethief Creek, where they congregate on Goldenrod if it's in bloom. The larvae can be found easily on the yellow-flowered host, with early instars in nests until the plant begins to dry out in the early summer. They go to ground as mid instars (where they are not easy to find), and resume feeding when the plants are again edible, as after summer/fall rains or in the spring. But they overwinter as mid instars whether or not there is a second brood.
|Too many to list. Truly polyphagous.
|Can be common at times, even early and late in the year.
|Limenitis lorquini powelli
|Willows (Salicaceae). This trail has Salix exigua, laevigata, and lasiolepis.
|Males patrol some of the places down the trail where willows grow.
|Three oaks are listed in Chester's plant guide: Quercus cornelius-mulleri; Q. wislizeni var. frutescens; and Q. acutidens (Fagaceae). Of the three, only Q. wislizeni is listed as a host for californica in my various books.
|Can be common on the trail, particularly in tree-lined canyons. Quercus wislizeni var. frutescens first appears on the trail near the junked car at the "Dolomite Mine". Overwinters as a larva.
|Ceanothus perplexans most likely.
|I hadn't really noticed this one before the spring of 2017 (late April), but they can become a regular part of the mix before numbers fall off again. Ceanothus perplexans - cupped-leaf ceanothus - is the likely food plant on this trail, but it doesn't seem to be a preferred host. It uses leucodermis in the Keen Camp Summit area.
|Epargyreus clarus californicus
|Probably Amorpha fruticosa (Fabaceae) here.
|Uncommon, but sometimes seen well down the trail, inc. at Horsethief Creek.
|Thorybes phylades indistinctus
|Amorpha fruticosa, possibly others in the Fabaceae family.
|Not common here.
|Pholisora c. catullus
|Chenopodium fremontii; Amaranthus species albus, fimbriatus, palmeri, torreyi; Ambrosia acanthicarpa (bur ragweed) possible here. But I believe I found an egg on Salsola tragus in 2023, but couldn't confirm because it didn't hatch.
|May 12, 2018 is the only time I've encountered one here.
|I found larvae Oct. 18, 2015 on Abutilon palmeri (Malvaceae) at Moeller’s nursery in Palm Desert; but that's not on the trail.
|A rare sighting here, but it turned up March 26, 2016, and since then a few times in the fall, most recently in October, 2019.
|Erynnis brizo lacustra
|Quercus cornelius-mulleri (Fagaceae)
|The host is plentiful, but this butterfly can be scarce on this trail, though it can be common in certain nearby habitats (as at Keen Camp Summit/Road). I once found a larva on this trail between two oak leaves that had been silkened together, and I've also watched a female oviposit, so it certainly can breed here.
|Gesta (Erynnis) funeralis
|Acmispon glaber and A. rigidus (Fabaceae) for sure. They sew leaves together to make nests. But caterpillars can be hard to separate from afranius until mature.
|A regular. Males may patrol areas inexhaustibly.
|Gesta (Erynnis) t. tristis
|Gordon Pratt says these can't really be separated reliably from funeralis without genital dissection (males). I assume some of the duskywings with white fringe on the hind wings are these as there is abundant oak here. Plant associations are crucial. Also, tristis likes to hilltop.
|Gesta (Erynnis) propertius
|Oaks, which on this trail means either Quercus cornelius-mulleri, which is relatively common here; Q. acutidens, which is uncommon; and Q. wislizeni var. frutescens, even rarer.
|Saw one on June 7, 2020 taking nectar on Eriogonum fasciculatum; that's my only sighting of this species on this trail. There is a June 9, 2019 record for the Santa Rosa truck trail on iNaturalist.
|Gesta (Erynnis) afranius
|It will oviposit on Acmispon rigidus (Fabaceae) here, even when A. glaber is nearby. These two are the dominant lotuses on the trail. Acmispon argophyllus is a good candidate as well, but it is rare here. Strigosus isn't common either on the trail but it wouldn't surprise me if afranius uses it some years.
|Noticably smaller than funeralis, and with hyaline spots, unlike brizo. Males are dark, with small hyaline spots; females have larger spots and more contrast to the forewings, and the hind wing fringe is usually a tan color. The similar E. pacuvius, which uses ceanothus, doesn't seem to be on the trail; it is in the San Jacintos, however. It probably can't use perplexans.
|Pyrgus scriptura apertorum
|Sphaeralcea ambigua (Malvaceae).
|Another small but sought-after butterfly. A fairly reliable spot on the trail is at the Sawmill Rd. junction just to the north, where the host is common and males patrol. Larvae make a silk shelter atop a leaf and place spicules in it to disguise their feeding area. They prefer low-growing mallow plants acc. to Gordon Pratt.
|Sphaeralcea ambigua (Malvaceae).
|Fairly common around the host at times. This and the following species fold and silken a leaf shut as larvae. Opening these may reveal one of the two; ericetorum have hairier heads.
|Sphaeralcea ambigua, Malacothamnus fasciculatus (Malvaceae). The latter was thought by the Emmels to be the favorite, and this plant is doing well now in burn areas along the trail. Apricot mallow is common on this trail. I'd like to monitor the field of Malacothamnusnorth of the trail in 2024 to see if anything is using it.
|Becomes common as spring turns to summer, esp. around patches of the host. In late summer they can be very common. There are three white skippers in the mallow patches here.
|Cynodon dactylon (Poaceae).
|Bromus madritensis ssp. rubens (Poaceae).
|More common in spring, but does fly late summer into fall as well.
|Agave deserti (Agavaceae).
|Always great to see these powerful flyers. Larvae burrow into the leaves of the host, which is plentiful on this trail. Stephensi flies ca. September-October. Can sometimes be found zipping around the hosts on the first leg of the trail not far from the trailhead, and at various places further down trail. A good flight in October 2019.