Utah Lepidopterist Volume 7 - No. 1, February 1997 The Papilio indra complex in Utah (excerpts) By Todd L. Stout
		(Click here for updated  and complete article)

INTRODUCTION

Previous lepidoptera publications describing the Papilio indra complex have labeled it as rare, fragile, isolated, and so forth. For example, William H. Howe describes it as follows: "The Papilio indra complex shows a considerable degree of geographic variation, especially in the southern parts of its range. Throughout its range the species is generally uncommon and specimens are rare in collections."

Clifford D. Ferris and F. Martin Brown add, "Because of its isolated habitats, indra is poorly represented in collections." Furthermore, according to John Adams Comstock, speaking of P. indra indra in Calif, "is one of our rare species, occurring in the higher altitudes of the Sierras...It is a difficult butterfly to capture, being rapid and erratic in flight." (Italics added.) But today, because of work by researchers and by many collectors who have become impassioned with indra, we know that it is not only more common than previously perceived--it has been recorded in every county in Utah save four; Sanpete, Iron, Wasatch, and Piute--but also, it is well represented in some collections.

The Papilio indra complex in Utah flies in a variety of habitats from desert swells, reefs, and limestone hills to the tops of the Wasatch Mountains. In fact, the butterfly has even been seen crossing valley floors between mountain ranges! It is true that indra does fly in some hostile environments. Its population numbers have been known to fluctuate drastically from year to year depending upon climate and parasitism. A large colony of P. indra minori in Emery County, was all but depleted between 1993 and 1995 due to heavy parasitism. Fortunately, this year (1996), minori has made a recovery there. One of the population stabilizing mechanisms of indra is the fact that their pupae can prolong diapause for several years in order to insulate against harsh or unfavorable conditions.

One of the elements that gives indra such an appeal to some collectors is its beauty coupled with its geographic variation. The indra swallowtail's geographic variation is peculiar in the effect that colonies which fly in moist montane habitat such as P. indra indra show much less individual variation than do colonies from the desert or from a semi-arid origin such as P. indra nevadensis or P. indra minori. The same phenomenon also seems to occur in California as montane colonies of pergamus and indra indra show a lower degree of individual variability as compared to the desert races of fordi and martini.

Utah currently has four varieties of indra; three named subspecies which include the typical race, minori, nevadensis, and one unnamed variety, "bonnevillei." Unlike its cousins from the machaon group, Papilio indra adults are not sexually dimorphic. In many Utah habitats, excepting most colonies of P. indra minori and P. indra nevadensis, indra flies sympatric with Papilio zelicaon; the former usually flying 7 to 10 days after the latter. The two species also share many of the same larval foodplants. However, zelicaon generally has a broader base of foodplants as compared to indra.

Although difficult and time-consuming, many collectors have been able to obtain attractive series of the different varieties of indra through rearing its caterpillars. One of the difficulties of rearing indra in the lab is the few species of plants--usually in the Lomatium and Cymopterus genera--which the caterpillars will accept. Obtaining these specific plants many times requires long distance travel to obtain. Another problem with raising indra in the lab that can be overcome through practices later discussed in this publication is their high susceptibility to microbial death. The two most common varieties of microbes that kill indra immatures are viruses and bacteria.

Others have obtained a decent series of some races of P. indra by collecting adults on the wing. Although Comstock describes the butterfly as being difficult to capture and erratic in flight, a little patience can overcome this obstacle through observation. In other words, indra males oftentimes will repeat their "erratic" courses as they fly similar aerial routes and land generally in the same spots. By predicting this repetitious behavior, specimens can be netted more easily. Some higher altitude males of P. indra indra exhibit this repetitive flying behavior, and have even been known pause from their aerial stunts in order to land and bask on snow banks!

Females, on the other hand, are much easier to capture as they more casually flitter in the vicinity of their larval hostplants. (The only exception to this is females of P. indra minori which tend to traverse their habitat in search of larval hostplant with much more haste.)

PART I: THE FOUR UTAH VARIETIES OF PAPILIO INDRA

Papilio indra indra

General:

The Type Locality of P. indra indra is vicinity of Empire, Clear Creek County, Colorado; Reakirt 1866. It is the shortest tailed race; some individuals exhibiting nothing more than a "stub." The nominate race is univoltine. The flight period in Utah varies depending upon elevation, snowfall, and larval hostplant. In the Bear River Mountains and in other isolated locations along the Wasatch Front where indra indra utilizes Lomatium grayi var. grayi between the elevations of 5000' to 7000', indra flies from mid-May to late July.

On the other hand, higher up in the Wasatch Mountains, where the larval hostplant (L. kingii) grows at around 8000' to 10,000', the flight period varies from around mid June to early September.

Utah Distribution and Habitat:

As discussed previously, the montane habitat of P. indra indra includes the Wasatch, Oquirrh, Stansbury, Bear River, and Uinta Mountain Ranges. Higher altitude males patrol and perch all day in search of females. Some of these males have been known to descend several thousand feet to canyon floors to nectar near rivers. (I.e, Provo Canyon, Utah County, and Big Cottonwood and Millcreek Canyons, Salt Lake County.)

Bionomics:

As stated earlier, the principal larval foodplant for P. indra indra in the Wasatch Mountains is Lomatium kingii (narrowleaf lomatium,) and the larval foodplant in the Bear River Mountains is Lomatium grayi var. grayi (milfoil lomatium.)

The ova is yellow-green, and is laid principally on healthy plants' peripheral ventral stalks. After a day or so, the ova develops rings and then turns black before hatching. From the time an egg is laid to the time it hatches is roughly six days in nature and five days in the lab. (Assuming room temperature.)

The young first instar larva is black with a thin, white saddle. As the larva moults into later instars, small white and yellow-orange speckles appear. Larvae of P. indra are much more timid than those of P. zelicaon.

The mature larva varies from black with off-white stripes to nearly all black with small yellow-orange dots. Hibernation is as pupa. For some reason, most lab-reared pupae emerge after two years of winter. Some pupae have been known to diapause for up to seven years.

Papilio indra minori

General:

The Type Locality of P. indra minori is Black Ridge Breaks, Mesa County, Colorado; Cross 1936. Minori is one of the most beautiful races of P. indra. Its large size with long tails combined with thin to intermittent cream bands and generous blue dorsal hindwing scales are diagnostic. Adults display a significant amount of individual variation. The bands on some individuals of minori are completely obsolete; showing the phenotype of what essentially is a black and blue swallowtail. It is the opinion of the author that this form kaibabensis which most authorities treat as a distinct subspecies really is a genetic drift morph of minori for two reasons. First, the kaibabensis form appears at least seldomly in mostly all minori populations. Again, its just an example of individual variation. Second, the habitat and bionomics of the two taxa are virtually indistinguishable.

Males hilltop on the tops of reefs, buttes, or even sheer peaks in search of females. In fact, minori males have shown intense aerial battles against one another in competition for females. Females, on the other hand, oftentimes fly in lower portions of buttes, or even in desert floors or swells in search of its larval hostplant. (Females only hilltop once to mate.) It is multivoltine depending upon rainfall; with up to three broods per year.

Utah Distribution and Habitat:

The distribution of minori in Utah is considerable. According to W.H. Whaley, over 50 distinct colonies can be found over Central to South-Southeastern Utah badlands. This distribution includes, but is not limited to, the West Tavaputs Plateau, Cedar Mountain, San Rafael Swell, San Rafael Reef, Capitol Reef National Monument, Henry Mountains, Cockscomb Ridge, La Sal Mountains, Abajo Mountains, and Monument Valley south to Northern Arizona.

Bionomics:

The larval hostplants of minori differ depending upon venue. In the San Rafael Swell, Cedar Mountain, San Rafael Reef, Capitol Reef National Monument areas, larvae utilize Lomatium junceum (rush lomatium.) At the Cockscomb Ridge, Monument Valley, and Abajo Mts, larvae use Lomatium parryi (parry desert parsley.) Also at Monument Valley and areas adjacent to Moab, larvae use Cymopterus terebinthinus (rock springparsley.) All of these larval hostplants are unique because they, for the most part depending upon rainfall, stay green and healthy from spring until fall; which accounts for the butterfly's ability to have multiple generations in one year.

Photos: Lomatium junceum & Lomatium junceum (closeup with ova)

The ova is yellow-green; developing rings and then turning black before hatching. The young larva is black with a white saddle. It is interesting to note that young minori larvae have a broader white saddle than young indra indra larvae have. The large mature larva is gorgeously arrayed with bright pink and black stripes strewn with orange dots. Immatures, unfortunately, are heavily subjected to several varieties of parasites. Egg parasites have recently been discovered in addition to the ever-so-prevalent small wasp parasites that kill third instar larvae and maggot parasites that kill fifth instar larvae. Hibernation is as pupa.

Papilio indra nevadensis

General:

The Type Locality of P. indra nevadensis is Jett Canyon, Nye County, Nevada; Emmel and Emmel 1971. In Utah, P. indra nevadensis is also known as P. indra nr. nevadensis. It is a long tailed race of indra. Amongst all the varieties of indra in Utah, nevadensis shows the most drastic example of individual variation with specimens looking like fordi, martini, panamintensis, and even pergamus. Nevadensis for the most part is univoltine with less than 1 percent of lab-reared pupae emerging during the same year. Adults of the Nevada Swallowtail fly early in the year; from mid to late March to early May.

Utah Distribution and Habitat:

The distribution of nevadensis in Utah is restricted to Washington County.

Bionomics:

Nevadensis immatures utilize two species of Lomatium in Washington County. In the vicinity of St. George, Lomatium scabrum (cliff lomatium) is the larval hostplant. Leaflets of L. scabrum burn off by mid to late May; which accounts for its one brood. However, leaflets of Lomatium parryi, which is its foodplant, further north, do not burn off until the fall. As such, it is plausible that nevadensis could at least have a partial second brood. Admittedly, more research needs to be done in this area.

Under typical conditions, females will only lay on healthier L. scabrum plants located between rocks or at the base of desert washes because these plants will thrive long enough to support the larva to maturity. However, in certain years, when population numbers are extremely high, it is interesting to note that females sometimes will oviposit on plants that cannot support the larva to maturity. Some Navajo Sandstone hills in Washington County do not have Lomatium scabrum on them except for North-facing washes and slopes. These hostplants only exist and survive there for two reasons: First, these washes and slopes accumulate more moisture and can support the roots of these plants. Second, plants in this area receive less direct desert sunlight as compared to south, east and west facing slopes.

The mature larva is similar to P. indra minori and is striped with bright pink-peach and black bands with yellow-orange spots. The pupa is salmon in color and camouflages well against Navajo Sandstone. As is true with all subspecies of indra, hibernation is as pupa.

Papilio indra "bonnevillei"

General:

Currently, "bonnevillei" is an unnamed race of Papilio indra. The name was originally under consideration by C.F. Gillette in 1987 and later dropped. Currently this unnamed race, also regarded as "West Desert indra" by local collectors, is being researched and considered to be named as a subspecies by W.H. Whaley.

The presenter of this publication feels that "bonnevillei" should have subspecific recognition for several reasons: First, "bonnevillei" is geographically isolated from nevadensis or nr. nevadensis. Second, P. indra nevadensis never have short-tailed morphs; P. indra "bonnevillei" does. Third, over a long series, "bonnevillei" has consistently more blue in the dorsal hindwings as compared to nevadensis. Fourth, some "bonnevillei" females exhibit extremely wide dorsal forewing bands that rival even P. indra fordi let alone nevadensis. Fifth, nevadensis documented larval hostplant Lomatium scabrum grows where "bonnevillei" flies. However, to date, "bonnevillei" immatures have not been found on it. Sixth, mature larvae of "bonnevillei" are drastically different to Washington County nevadensis.

"Bonnevillei" is short to medium tailed, and has one flight per year. The flight varies depending upon winter precipitation. At 5000', "bonnevillei" generally flies from mid/late April to mid/late May.

Utah Distribution and Habitat:

Colonies of "bonnevillei" exist in many North-South ranges in Utah's West Desert including but not limited to the Dugway Range, Thomas Range, Fish Springs Range, House Range, Confusion Range, Little Drum Mountains, and Wah Wah Mountains. All of these mountain ranges contain Limestone and exist in the vicinity of what was Lake Bonneville. These limestone hills is where the larval hostplant lives.

Bionomics:

The larval hostplant is Lomatium grayi var. depauperatum. This plant seems to die off faster than any other host of indra. The young larva has perhaps one of the most slender white saddles as compared to other subspecies of indra. As the larva matures, this saddle has been known to disappear altogether. Third instar larvae of "bonnevillei" change their resting position to the base of the hostplant where they are difficult to find. The mature larva has two basic forms from mostly black with tiny yellow dots to black with medium cream bands. The mature larva somewhat resembles the larva of P. indra indra.

Utah Papilio indra Subspecies and Larval Foodplant Matrix

**All subspecies of P. indra will gladly and readily accept L. kingii.

dLF = = Documented Larval Foodplant

YES = = Suitable Lab Foodplant

NO = = Not Suitable Lab Foodplant

??? = = Unknown

(A) P. i. indra 4th instar on L. kingii

(B) P. i. "bonnevilli" 5th instar on L. grayi

(C) P. i. minori 4th instar on C. terebinthinus

(D) P. i. minori 5th instar on L. junceum

References 

1. Emmel, Thomas C. and Emmel, John F. 1973. The Butterflies of Southern California p. 12.

2. Howe, William H. 1975. The Butterflies of North America p. 396.

3. Ferris, Clifford D. and Brown, F. Martin 1981. Butterflies of the Rocky Mountain States p. 184

4. Comstock, John Adams. 1927. The Butterflies of California, p. 21

5. Gillette, C.F. Col. Utahensis: Journal of the Utah Lepidopterists' Society l984 4.2, p.34.

6. Whaley, W.H. Personal Communication. 17 Jul 1996.

7. Gillette, C.F. Col. Personal Communication. 5 Jul 1996.

8. Whaley, W.H. ibid.

  Return to HomePage