|home Howatharra Botanical Photo Gallery Howatharra Plant Species List pdfs maps links|
FIELD NOTES on the BEHAVIOR and PHENOLOGYof Carthaea saturnioides (Bombycoidea: Fam. Carthaeidae)
a Spectacular Moth Endemic to SOUTHWESTERN AUSTRALIA
P.O.Box 277, Hereford, AZ 85615
This paper documents many details of the foodplants and life history of Carthaea saturnioides Walker never before published. The observations reported below are taken directly from field notes written in 1968, when I was Assistant Curator of Insects at the South Australian Museum (Natural History) in Adelaide (1965 - 1970). Later, when I was resident for seven years at Drummond Cove, near Geraldton, W.A. (1972 - 1978), the observations on Carthaea around Oakajee and Howatharra were added to the notebook (1974 - 1977). This moth is the only known member of its family.
From late October to early December of 1968, I undertook a 6-week springtime collecting trip, throughout the southwest of Western Australia, in the company of the late Dr. Norman B. Tindale, then emeritus on our staff at S.A.M. We traveled in my 1964 Holden ute (pick-up truck), and camped out most of the time, running an 8-watt UV light (off the car battery) whenever possible. We criss-crossed much of the region from Geraldton to Esperance, and thence west and south to the southwesternmost reaches of the continent, at Cape Naturaliste and Cape Leeuwin. My primary focus throughout this trip (in addition to general insect collecting for the S.A. Museum) was to locate and learn as much as I could about the early stages of Carthaea, which desire was abundantly fulfilled during these explorations. The handwritten notes, from which this paper is transcribed, were entirely recorded in the field during the 1968 trip, while the subject matter was right in front of me! The various preserved components of these Carthaea studies, code-numbered Ca.1 (Toolbrunup), Ca.1A (Needilup), and Ca.1B, Ca.1C, Ca.1D, were deposited in the S.A. Museum (Adelaide) and the W.A. Dept. of Agric. (South Perth).
Tindale's primary entomological focus on this trip was his beloved genus Geitoneura (Satyridae), on which he had been gathering ecological and other observations for much of his lifetime. I believe that most of his extensive field notes on this genus still remain buried within his vast array of handwritten "journals," unpublished.
Earlier rearing efforts over many years (1948 to 1964), involving various southwestern U.S. sphingid and saturniid larvae (Euproserpinus, Agapema, several Hemileuca spp., and Saturnia albofasciata in particular), prepared me well for my first rearing attempts with Carthaea larvae... It was not necessary for me to learn the hard way about the vital importance of daily sunshine and fresh air, which would prove to be imperative for success with Carthaea! This important lesson was already well embedded in my mind, when I happened upon this spectacular "ecological convergent" of our North American Hemileuca spp. (very much "sun-lovers" as larvae) -- see also McFarland 1966, 1974, and 1988: 366 (columns 1-2).
FIELD NOTE (19 Nov. 1968): WESTERN AUSTRALIA, Stirling Range, near Toolbrunup Peak (Ca.1). Carthaea larvae were abundant on the proteaceous dwarf-shrub, Banksia sphaerocarpa R. Br. HABITAT: This is a rich and varied sclerophyll shrub association, with many species of low, woody shrubs (especially various Proteaceae, dwarf Myrtaceae, and shrubby Casuarina spp.), and a rather uniform scattering (isolated emergent individuals and small groves) of mostly slender, small eucalypts; larger eucalypts are confined primarily to the ravines of surrounding hills and mountains. Soil lateritic (nodular light brown ironstone pebbles, of a common Western Australian type), with solid rock at the surface in many places. The above foodplant was not encountered in adjacent areas having the usual fine, white sandy soil. This particular location had a great abundance of larvae, but the area of maximum concentration was of very limited extent. Larvae of all instars from first to penultimate (but primarily first, second, and third on this date) were present; also, some recently deposited eggs were found on a few of the Banksia shrubs. This population was centered around the edges of a roadside gravel pit or quarry, and along a little-used road or track off the side of the main road, entering the gravel quarry. Fewer larvae were to be found on the same plant in the uncleared or "virgin" scrub, which everywhere surrounded this quarry. The quarry provided a sort of "edge effect" [see also McFarland 1967: 9 & 1988: 78, col. 3; Courtney 1982; Shapiro 1984] in a vast sea of otherwise undisturbed and rather uniform sclerophyll heath or kwongan (see Beard, 1990). Several "spot checks" were made nearby, along the main road: About one mile further up the road was another area of concentration, at a somewhat higher elevation (not far below the pass), along both sides of the road. Here the larvae were smaller -- first and second instars only. About two miles further along the road from the gravel quarry, only a couple of small larvae could be found on the many plants of B. sphaerocarpa that we searched. Other areas, several miles west of the quarry location, where the same plant was also noticed, did not seem to have any larvae present at all.
Only the soft and tender, yellowish-green new leaves of this sclerophyll plant are eaten; the tough previous year's foliage, which is a much darker shade of green, is not eaten. The plant is unlike any other low, sclerophyll shrubs in this habitat, and is easily spotted at this time of year due to its two shades of green (yellowish-green on the upper growing tips, contrasting with the dark green older leaves below). Form is low and rounded, with easily-broken woody stems which are mostly upright. The leaves are narrow-linear and minutely spine-tipped; margins are smooth, parallel, entire, and revolute beneath. The tender new leaves quickly wilt after stems are picked, soon becoming unacceptable to captive larvae.
EGG: Encountered on Banksia sphaerocarpa. Six eggs, presumed recently oviposited (because of their uniformly pale and translucent yellowish color) were found during a search over many bushes. They were in two groups of three eggs each (on two widely separated plants), fairly well glued to leaf and upper stem surfaces; adhesive colorless. Form rounded-elliptical and rather plump looking. Shell relatively thin but hard, the surface very shiny and smooth, with a gleaming surface luster over the translucent (internal) yellowish color. As the adhesive is colorless, there are no reddish or brownish smudges, or other markings on the surface, as seen on the eggs of Antheraea, Hyalophora, or Saturnia, for example.
The discovery of many dozens of first, second, and third instar larvae, occurring almost invariably in groups of two, three, or four of any one size (not yet dispersed over the plant), would seem to indicate that the eggs are typically deposited in small batches of perhaps two to five, with two or three probably being the usual clutch size resulting from any single stop made by an ovipositing female. In addition to the recently deposited eggs, two other batches of partially eaten egg shell remnants were also found (two in one batch, four in the other); all of these shells were about 1/3 to 2/3 eaten, and the tiny, all-black, spiny larvae were conspicuous at rest nearby. The empty egg shells were completely colorless and clear, and remained firmly attached to the foodplant leaves ... As the first instar larva is a dull black when newly hatched (before extensive feeding), the eggs could be expected to show darkening internal color changes as they incubate, no doubt clearly visible through the transparent chorion. EGG SIZE (3 discernible dimensions) = 1.85 - 1.70 X 1.55 - 1.50 X 1.50 - 1.45 mm. These measurements, recorded in diminishing maximums, reflect the full extent of variation seen in the three dimensions of all eggs measured (length of largest egg seen was 1.85 mm; length of smallest egg seen was 1.70 mm., etc.). Metric-dial calipers were used. [See also the four egg papers, McFarland 1970, 1972 (2 papers), 1973.]
FIRST INSTAR: (Nov. 20th): A silk-dropping ability was noted for recently hatched larvae, but not for any of the later instars (i.e., only the first instar is able to drop on a silken thread if dislodged). Clings with only slight tenacity, but is not quick to let go or drop when prodded. These small and spiny black larvae are highly conspicuous amongst the light yellow-green new leaves of the above-named foodplant; they rest fully exposed, making no attempt to hide.
PENULTIMATE INSTAR (Nov. 20th): This description is based on living larvae from the Toolbrunup locality. When filled out, ground color is dull grayish-black on dorsum and sides. Conspicuous subdorsal blotches are rust-brown or orange-brown. Venter grayish-white extending up into basal area, where there is a pale tan tinge. Lateral proleg shields tan and shiny. Cervical and caudal maculation light yellowish-tan. Spiracles black, closely encircled by dull gray and then by white, then by black rings, which are again semi-encircled from beneath by broken white U-shaped rings (open above). Setigerous tubercles of the dorsal, subdorsal, and supraspiracular rows are metallic blue-black, and gleam in the sunshine. These are more intensely brilliant in recently moulted larvae than in filled-out individuals. Other setae black with white tips, rather like flimsy bristles which are flexible, eventually becoming somewhat curled toward the tips (smooth and straight only when new). Truelegs tan and a little glossy. Ground color of head a rich yellowish-tan, marked with narrow lines of jet-black on a matte surface; there is no surface sheen whatsoever.
Locomotion is rather "clumsy" or lumbering, and they are quite easily dislodged. Skin soft and thin; the larvae seem quite feeble or "limp" when first handled, although they become somewhat more firm when curling up. May curl up into a ventral C-curl for a short time when first handled, or may not. Sometimes regurgitates if suddenly grasped. Others may thrash the forebody from side-to-side, or will sometimes let go and drop (rarely). No silk is ever woven at places of rest, and they never attempt to hide.
As the larvae get older (past second instar), they absolutely require fresh air and frequent sun exposure to trigger vigorous feeding, and to maintain good health. The tender new leaves of the foodplant must be fresh or they will refuse to feed. Repeated observations, throughout a 22-hour period in the Toolbrunup locality, showed that these larvae are strictly diurnal feeders in later instars, and that they "sleep" (on stems, a little below the growing tips) all night, never shifting their positions or feeding at all after dark. They move up again in the early morning (around 0700 hrs.) to begin slow feeding, even on cloudy-dull mornings. Feeding continues on and off throughout the day, until sunset. If the sun breaks through later in the morning or early afternoon, feeding becomes far more active and rapid, and they show a strong inclination to bask between feedings (stretching out in order to soak up the sun). There is almost constant air movement in this windy region. If these typical conditions of their natural habitat are reproduced in captivity, they can be expected to thrive. However, they will rapidly decline (and die!) if deprived of sunlight, fresh air, or fresh foodplant daily. As with numerous "sun-loving" larvae, the earliest instars (first/second only) seem less demanding of the natural conditions, and are able to tolerate captivity with little or no sun-exposure. Thus, a closed jar (which keeps the foodplant fresh for several days) works well for very young larvae, and saves labor by less frequent need to provide fresh foodplant.
Many larvae at the Toolbrunup locality were carrying numbers of white, elongate eggs of an unidentified tachinid fly; a few of these larvae were preserved. During late morning, when the sun was bright, a smallish tachinid fly was seen flying in and out of a B. sphaerocarpa bush , in which were 9 Carthaea larvae of various sizes. The fly suddenly landed on one (a third instar), presumably to oviposit, but the larva instantly detected it and began rapidly twitching its forebody, causing the fly to depart. It then landed on the ground a short distance from the foodplant, but I was unable to capture it. No other tachinids were seen thereafter.
Larvae as conspicuous as these, concentrated in large numbers in a small area, could be expected to be heavily parasitized, as indeed these were. It is a wonder that any of the large Carthaea larvae escape detection by tachinid flies. Some bushes contained as many as eight to ten conspicuous larvae, and many had between three to five larvae in them. The majority of bushes harbored two or three, and a few had singles. Some bushes contained all larval stages present side-by-side, from first through penultimate instar. Although univoltine, these moths appear to have a relatively long period of emergence and oviposition. They are probably on the wing down south from the first warm weather of early spring (about mid September to early October), continuing on into late November or early December (early summer). Near their northwestern limits (Geraldton region), the flight begins and ends much earlier (extending only from about mid/late August into September). These moths are strictly nocturnal in flight. All-night-to-dawn collecting would be imperative to get any accurate impression of their relative abundance in a locality. The majority of arrivals at light should not be expected until sometime past midnight.
ADULT: A single, somewhat worn male, of this univoltine, spring-flying bombycoid, came to ultraviolet light (G.E. F8T5/BL) near Toolbrunup Peak, on November 20th between 0300-0400 hrs., after a rather cold and windy night. DISPLAY: This male exhibited a high tectiform resting position, with no hindwing exposure (see McFarland, 1988: 238-39, 4th page of Appendix I, IBClosed Tectiform, and Ch. 33 on page 162, describing a moth with similar warning behavior). Upon being tapped or handled, it would drop and perform a distinctive rhythmic display: Head depressed to the ground, with antennae held parallel and straight out in front (along the ground), and the hindwings up, but in the same plane as the forewings. While the latter were kept still, the hindwings were moved rhythmically apart and together again, more rapidly if the moth was aggravated, then gradually terminating all movement if not further disturbed. During display, the abdomen is held in a fixed position, gently arched downward with its tip touching the ground. The legs are positioned so as to elevate the wings with their dorsal surfaces facing forward (in the manner of the tail of a displaying peacock). The hindwing eye-spots are thus rendered visible during the display. Photographs of the above-described displaying male were taken from several different angles, to illustrate various details of the display. After a long period of rest, "shivering" is necessary before flight is possible. The only other adult collected to date, earlier on this trip (alas, also a male!), came to "black light" about 0400 hrs., on November 10th, at our camp 25 miles ESE of Lancelin, near the Moore River, Darling Range (N. of Perth); a fresh specimen.
Over 50 penultimate and last instars (mostly not yet filled out) were easily collected during a 45-minute search, in just two D. cirsioides patches close to the highway. Numerous smaller larvae (mostly penultimate) were left behind. The smallest larvae encountered here were three first instars (filled out), and these were preserved. On this date, in a year which appears to be running "late" (season abnormally cool), the majority of larvae seen were still in penultimate instar (filled out), or in early last instar (newly moulted). Only about seven fully grown last instars were found here. The time of this search on was between 16-1700 hrs. of a warm and sunny afternoon, at which time most of the larvae were still out and feeding actively in the bright sunlight. Penultimate instars awaiting the final moult were also present, but kept themselves somewhat hidden beneath dense foliage, resting closer to the main stems.
Recently moulted last instars were seen devouring their cast (penultimate) skins, as they stretched out and basked in the sun after moulting. Many others (last instar and penultimate) were observed either feeding rapidly, or lumbering about clumsily over the very spiny D. cirsioides foliage, in search of more new leaves on which to continue feeding. They are easily dislodged, clinging with but slight tenacity, and stand out incongruously on these plants. They do not look as if they "belong" on this plant at all!
If a last instar is touched, it will usually release its hold on the plant and thrash suddenly to one side or the other (into a lateral "C-curl"), with the head somewhat retracted. If further prodded, it continues to thrash still more violently (side-to-side), and may eventually cause itself to fall from the plant if the thrashing continues. This behavior is very reminiscent of certain sphingid larvae (Hyles spp.) when disturbed. Also like Hyles, it will sometimes regurgitate when suddenly contacted, especially if grasped near the rear end. It may then thrash back, spitting as it does so, although this is not as copious as would be expected in Hyles. When first picked up, it may remain in the lateral C-curl for a short time before moving again. When handled gently, it usually just keeps on trying to crawl away, showing little or no other response. They quickly "adjust" to handling and then fail to register further annoyance.
Nearly all of these larvae were found to have numerous white eggs of a tachinid fly attached to them (varying from two or three to ten or more per larva). These eggs are easily "popped" by the careful use of sharp-pointed forceps, and those still unhatched can be seen to squirt out a minute amount of fluid when being thus pinched. (This is always worth trying in the case of any valuable larva, which is found to have parasitoid eggs attached to it at the time of collection.)
LAST INSTAR (Nov. 23rd): The living larva is dull grayish-black on dorsum and sides (a few are dull gray, not black at all). Ground color below this, and extending down onto the venter, is a pale tan-gray with a very faint pinkish tinge; it turns a much deeper pink in alcohol, but this is not the true (living) color. Prolegs pale yellowish-tan. The conspicuous subdorsal blotches are dull rust or red-brown, finely speckled with dull black. These blotches are irregular in outline, and vary greatly in size from one larva to another; in some they are nearly absent, or reduced to very small, irregular spots. The jet-black spiracles are ringed by pale gray with a slight gloss. These gray rings are, in turn, encircled by another ring of black; above this is an arc of dull, pale yellowish-tan; below this, and up to either side (nearly or completely contacting the yellow-tan upper arc) is a whitish mark that half encircles the black ring from beneath. Approximately along the spiracular line is a zone of transition from the dull black dorsal coloration to the (pinkish) gray-tan ventral ground color -- not a sharply defined line. Truelegs slightly glossy, yellow-tan. Head dull yellow-tan, strongly marked with black lines (matte; no surface sheen). Cervical shield similar to head color, with black markings. Suranal plate pale yellow tan, as are lateral shields of anal prolegs. All formerly conspicuous setae and iridescent blue-black tubercles, etc., and the orange of the subdorsal markings, as seen in penultimate instar, are now gone. At first glance, the final instar is a vastly different larva, although its head is much the same as in penultimate, and so is the encircling maculation around the spiracles. Skin texture is smooth, silky-soft and rather "thin." There is no surface gloss or shine, even in "plump" or filled-out larvae. Healthy last instar larvae, when close to full size, are quite firm to the touch, in spite of the thin, soft skin; more recently moulted individuals (early last instar) often feel rather "limp" when handled. During handling, the tactile impression of a full-sized last instar again recalls the mature Hyles larval body form.
The first response to a minor disturbance is simply to remain in the same position, while retracting the head under and ventrad, producing a modest sphingiform stance. However, there is no pronounced rearing back when the head is retracted. If no further annoyance follows, there is then a gradual return to feeding. A further prod will usually elicit twitching or more vigorous thrashing, depending upon the degree of annoyance.
These larvae are more easily discovered on sunny days because of their great propensity for sun-basking. This means that all larger larvae (except those remaining hidden in preparation for a moult) are moving around on top of the plant throughout the day, gradually relocating so as to always remain maximally sun-exposed. Thus, early morning or late afternoon hours find them all concentrated entirely on the most intensely sunny side of the (columnar) D. cirsioides plants. When under strong sunlight, they feed with great vigor and rapidity, whereas they only feed slowly during cloudy periods, or earlier in the morning. At night they always remained totally inactive (never seen crawling or feeding).
On Nov. 23rd (sunny afternoon), another search was made well to the north of the most productive area close to Needilup. This was at about 3/4 mile WNW of Needilup, where many more plants of D. cirsioides were found, emergent above the surrounding undisturbed low heath scrub. Here, too, the larvae were abundant, but only of localized occurrence. All larval stages were found except first instar. Most were penultimate or last instar (not yet filled out). After about two hours of searching, I was able to locate 28 plump final instars; these were to be kept alive in the hope of soon obtaining healthy pupae, with no need for extended care after we returned to Adelaide. Immediately after collecting, I carefully scrutinized all of them and "popped" any visible tachinid eggs, many of which were still firm and unhatched. Most of these eggs were attached in the region of the head and thorax, or in folds between segments, some even on the venter, but mostly lateral or dorsal in placement.
The 28 larvae collected for rearing were all confined together in one large, square plastic wash-basin (see photo), which was kept directly open to the sun whenever our travels would permit. It was also left wide open to the night air and (usually) heavy dew, a typical feature of this habitat. As these larvae have a rather clumsy, lumbering locomotion, and little clinging ability in the prolegs, and cannot weave a silken pathway on which to climb, they are easily kept in a smooth-sided open container, with no danger of escape. The basin was filled to a depth of about 2 inches with surface soil from the habitat. On top of this was a one-inch layer of typical surface leaf litter (Dryandra, Grevillea, and mallee) from beneath the plants. Every morning, I would introduce upward-pointing shoots of tender new D. cirsioides tips (from which I had removed all of the, sharp-spined older leaves), while retaining a 3-inch barrier of smooth sides all the way around inside of the basin. The larvae kept in this way quickly settled down to quiet feeding when placed in the sunshine. After resting all night in the container, they would suck up dew drops and begin feeding early in the morning (07-0800 hrs.), even when a cloud-cover was present. As the sun became brighter (usually by about 1100 hrs.), they began feeding more avidly and showed no discomfort at being crowded. Taken out of the sun, they soon exhibited distress and began wandering about, refusing to feed. Their simple requirements were thus rendered quite obvious! (If catered to, they are no trouble at all in captivity.) It is only a matter of introducing plenty of fresh foodplant each morning, after they have been warmed by the sun. Sprinkle the foliage lightly, if the night dew has been missed by the captives; they will usually drink, and probably require a little water at least every few days for optimum health.
Further searching by N.B.T., around the Needilup locality, revealed a few penultimate and last instar larvae on Banksia caleyi, which has large and very tough, spine-toothed sclerophyll leaves; the new leaves are heavily brown-pubescent and very soft. (They were, of course, eating only the tender new leaves.) This is a large and rounded, woody bush, of somewhat open and sprawling growth habit, with large red flowers, erupting far down on the woody branches. The larvae appear rather more "at home" on B. caleyi, being able to rest outstretched on the long leaves or stems, instead of having to clamber about precariously over densely spiny terminal heads, as they do on D. cirsioides! However, the latter clearly seems to be the "preferred" foodplant in this locality.
As a matter of interest, they also readily accepted Dryandra pteridifolia R. Br., which has a low and rounded but upright growth habit, with all of its leaves springing from one basal point, very close to ground level; older leaves are heavily sclerophyll, young leaves brown-pubescent and quite soft. The leaves of this Dryandra are up to 18 inches long and very deeply toothed, almost to the point of being pinnately divided. This plant was not growing at the Needilup locality, but was rather common around Jerramungup and eastward, scattered throughout the rich and varied heath associations growing along the highway to Ravensthorpe.
FIELD NOTE (23 Nov. 1968): WESTERN AUSTRALIA, at Jerramungup, between 17-1800 hrs. -- a patch of D. cirsioides covers a rather large area here, among mallee eucalypts and other (lower) scrub, just to the south and west of the school grounds. This patch contained larvae of all instars, from second to early final, but they were by no means as common here as they were around Needilup.
Both here and at Needilup, it was noted that certain D. cirsioides plants (usually small groups of them rather than isolated individuals), were under attack by scale insects attended by ants, and the "honeydew" produced by the scales had caused a growth of black sooty-mold on the woody stems and all older (or lower) foliage. Such plants were further characterized by a paler yellowish-green and "sickly" looking new growth. In no case, in any locality, was even a single Carthaea larva found on such scale-infested plants. The ovipositing females probably avoid these plants (?) -- or, if they do not, then perhaps the ants remove any young larvae as soon as they are discovered....
The huge DROPPINGS of last instar are most distinctive in their shape and formation, and are exceptionally firm (well consolidated). In color, they are mostly pinkish-tan, if from larvae feeding on D. cirsioides. The unique frass alone would readily serve to indicate the presence of this species, even if one has arrived too late to find any larvae. Many of the droppings fall down into the dense leafy rosettes of the foodplant leaves and remain lodged there, baked hard by the sun; others are conspicuous nearby on the ground. (Many such frass pellets from Needilup were collected and preserved under the code-number "Ca. 1A" at the S.A. Museum.)
FIELD NOTE (Nov. 24th): 10 miles E. of Jerramungup. One last instar (only) was found on D. cirsioides, in a large patch of this plant near a roadside gravel pit. (Most of the plants in this place were at least partly covered with sooty mold.) Also found in the same locality, was one first instar larva (Ca. 1B) on new leaves of D. pteridifolia R. Br. There was no cirsioides nearby, indicating that the oviposting female had clearly selected pteridifolia in this case. Three miles east of this location, a few more larvae were found on D. cirsioides and also on Banksia ?caleyi (or possibly a related species with cream-colored flowers).
FIELD NOTE (Nov. 24th): 17 miles W. of Ravensthorpe. We stopped for a quick "spot-check" at this location, which was suggested to me by Ian Common. Several penultimate instars were located here on D. cirsioides within only a few minutes, but none were collected.
FIELD NOTES (Nov. 25th): Nine miles south of Ravensthorpe, along the road to Hopetoun, around the borders of a gravel pit, we noticed D. cirsioides abundant here, so stopped for another "spot check." A few penultimate and last instars were present. Most notable observation here: 2 third instar larvae were found on two widely separated shrubs of the intensely red-flowered Grevillea concinna R. Br., feeding on the long and linear new leaves of this sclerophyll shrub, which was widespread along the road to Hopetoun, and also east of Ravensthorpe. Both plants having larvae on them were not growing anywhere near to D. cirsioides, so there was little doubt that the ovipositing female had selected them. A few more "spot-checks" were made for evidence of Carthaea larvae, in three other locations along the highway east of Ravensthorpe, as follows:
(a) 23 miles E. of Ravensthorpe: D. cirsioides common, but no larvae (nor even dry frass) were in evidence here.
(b) 49 miles E. of Ravensthorpe (one mile west of Munglinup): Both D. cirsioides and D. pteridifolia (and a close relative) were common here, but only two larvae (last instar) were located; these were feeding on the soft, brown-pubescent new leaves of pteridifolia. No evidence of larvae (nor last instar frass) could be found on any of the cirsioides plants here. (We searched for about 30 minutes.) The two larvae feeding on pteridifolia were preserved for the larval collection (Ca. 1C).
(c) 63 miles E. of Ravensthorpe: A habitat similar to (b), and with the same two foodplants present, but no larvae or frass could be located on either of the two Dryandra spp. here.
The localities one-half to one mile W. of Needilup, and SW. of Jerramungup school, were originally mentioned to me by Mr. J.A. Mahon, C.S.I.R.O., Wembley, W.A. (Perth suburb), who had collected Carthaea larvae there for I.F.B. Common several years earlier (see Common 1966). Mr. Mahon also mentioned "43 miles W. of Ravensthorpe, just off the main road," as being a good location for Carthaea larvae on D. cirsioides, but we could not find any cirsiodes growing there! Several last instar larvae were preserved from the Needilup location (Ca.1A), in addition to the 28 others that were kept for rearing; I also preserved a series of filled-out penultimate instars from Needilup, plus many others from the Stirling Range locality (under Ca. 1), from B. sphaerocarpa. The Needilup location was by far the most productive for last instars on the dates we visited there (Nov. 22-23).
From the many searches we made, it gradually became evident that these larvae are to be found in certain very specific small areas in far greater abundance than in others, regardless of the presence of D. cirsioides nearly throughout the Needilup to Ravensthorpe region (and to the east and south of there). This reflects a distinctly patchy or localized distribution within the overall range of the species. Of all the places we encountered Carthaea larvae, the Stirling Range population was the least advanced by mid to late November, while the Needilup population showed the greatest range of instars present all on the same date (first through final instar).
All foodplant names recorded above were confirmed by Mrs. M. Kenny, S.A. Museum botanist, and they were also shown to Paul Wilson, plant taxonomist at the W.A. Dept. of Agriculture in South Perth, for additional verification. NOTE for future attempts at similar rearings: The plastic container (open basin) idea was excellent for the requirements of the last instar larvae, but it was not very suitable for pupation, especially when in transit over endless miles of bumpy and corrugated dirt roads! It probably would have been acceptable had the container been standing quietly in one place the whole time. However, as many of the pupae were being formed during our travels over rough roads, some of them ended up badly deformed due to angular pieces of litter shifting about and jutting into the cocoons, thus denting the newly formed (soft) pupae within; additional damage was caused by partial collapse of the (flexible) cocoon walls down onto the newly formed pupae, etc. As a result, only 15 of the original 28 produced good (or fairly good) pupae; all the rest were badly dented or deformed, even though they came from healthy looking mature larvae (a tough lesson learned!).... No parasitoids have emerged from any of the 15 good pupae at this time (Jan. 1969), although some might be anticipated closer to emergence time next spring (?).... All pupae are still responding readily with abdominal movement when handled. A specially constructed, "cave-in proof" false bottom, with abundant partitions for separated cocoon formation, could be fabricated and inserted into the bottom the rearing basin, for any future attempts at travel-rearing. This would probably lead to more successful pupation, even during the relentless hammering of back road travel....
PUPA: Very tough-shelled, blackish, not shiny. At first glance, somewhat reminiscent of the pupae of certain North American Hemileucinae, especially Pseudohazis, and they are housed in the same style of silk-tied debris-cocoon, on the ground in the shade of shrubs, just beneath surface litter. Cocoon silk tough and colorless, of a fairly open weave which ties together adjacent litter, at or just below the soil surface (presumably under leaf litter in the shade of shrubs). These pupae are quick to respond with abdominal movement to any touch, and they are far more lively or readily responsive than are the pupae of Pseudohazis or Hemileuca spp., although the movement is not particularly fast; it can be varied from side-to-side to almost circular.
After emergence from its pupa, which was lying on damp sand in a "Henne Pupa Pot" (see McFarland 1988: 366, col. 3; 367, cols. 1-2, for details), the first male crawled slowly up the side of the container and onto the top netting, where it soon settled with its wings hanging straight down (0826 hrs.). Wing expansion was completed by 0905 hrs. (40 minutes). After about 47 minutes, the wings were firmly pressed together into the commonly seen downward-hanging, veliform "drying-phase" (typical of most large moths), and were held this way for the next 82 minutes; thereafter, it assumed a partially normal resting posture for this species (i.e., flattened tectiform, with no hindwing exposure, and the antennae still out). This switch, from the veliform drying position to the partial resting posture, was a slow movement -- not the sudden "snap" seen in some moths; it took about one minute of very gradual wing-opening, accompanied by much wing-twitching as the change-over neared completion, but no rocking movements (see Blest, 1957); antennae remained still during this process. The typical (higher tectiform) resting position was assumed about one hour after initiation of the partial resting pose. Timing of this was not precisely recorded, as the moth had been subjected to repeated disturbance during photography of its partial resting pose (see photos). The typical or final resting position differs from the "partial" as follows: It is a higher tectiform, with almost no hindwing exposure, but for a narrow strip sometimes visible along the inner margin, and the antennae are now completely tucked under the wings, out of sight. Once fully dried, the male proved very quick to respond to even the slightest disturbance -- not quiet and easily-handled, as are so many nocturnal bombycoid moths in the daytime. [For a complete terminology of resting positions in the Lepidoptera, see McFarland 1988: 235-243.]
NOTE on reactions of a living adult female: This moth was at rest in its normal tectiform resting posture, hanging from the top of a pupa-pot (1730 hrs.). I gave it only a light touch and it instantly "awakened" to begin wing-trembling, preparatory to take-off and flight.
The gravid female's abdomen is surprisingly small and thin for a newly emerged female bombycoid moth of this size, probably indicating that the total number of eggs is not great. (This remark is based upon seeing three newly emerged females which had not yet deposited any of their eggs.)
LATER FIELD NOTES
13 October 1974: WESTERN AUSTRALIA, Moresby Range, Oakajee District, on Bowman's farm (about 16 miles NNE. of Geraldton), on the NE-facing lower slopes of rocky hills east of the house, on the way to my Comocrus hilltopping study site (see McFarland 1976), I noticed recent extensive feeding on the light green new leaves and branch tips of the very spiny-leafed Dryandra fraseri R. Br., an abundant and widespread low shrub of this district, typically found on brown lateritic gravel; the flowers are cream-white, and the mature foliage is a distinctive bluish-green. Closer examination revealed several of the unmistakable large pinkish-tan final instar frass pellets, but no larvae. Four of these pellets were saved for the dry collection. The larvae had already left to pupate, probably just a few days earlier. At this latitude (about 28° 35 min. S.), I am guessing that late September to early October would be the best time to find mature larvae north of Geraldton.... This was my first evidence of Carthaea in the Geraldton district (a northernmost record for me). Geraldton is more than 500 miles to the northwest of the various southern localities described above.
24 September 1976: WESTERN AUSTRALIA, Moresby Range (about 19 miles NNE. of Geraldton), at Howatharra Hill Reserve (see McFarland 1977), in a large gravel quarry located about 100 yards east of Zone 4 (S); also, a few were found in an area just south of Zone 3 (SC). On this date, approximately 40 young larvae were found, mostly second and third instars, and a few still in first. In all cases, they were eating only the most tender (pale green) new leaves of Dryandra fraseri. All of the larvae were concentrated on just a few plants in a relatively small area, on a low rise with a rocky surface and an abundance of brown laterite pebbles. There were usually 2 to 4 larvae per bush (rarely singles), again reflecting the typical mode of oviposition in small batches, as seen down south in 1968. None were collected on this date. 2 October 1976: Returned to the above location and found them now mostly in 3rd - 4th instars, growing rapidly and feeding avidly in the hot spring sunshine. 8 October 1976 (with Muriel and Norman B. Tindale): Returned again to the same location, and found them now (only six days later) mostly in penultimate or last instar, and some had already departed for pupation! Brought home six large individuals to rear at Lot 68, Drummond Cove, where we were resident from 1972 - 1978.
25 August 1977 (with Lisa Green): Same Howatharra location as above. We found only one second instar, after extensive careful searching in the same Dryandra fraseri patch described above; no eggs seen (perhaps a little too early?).... It is also possible that Carthaea may be somewhat cyclic from year to year, and/or that the typically localized populations may "rotate" or shift throughout suitable habitat (as often seen in Hemileuca juno in SE Arizona), probably due to random dispersal by ovipositing females. There are many (apparently) suitable patches of D. fraseri, growing on brown lateritic gravel, throughout the Oakajee-Howatharra-Nabawa district (N. of Geraldton), especially toward the east end of the Howatharra-Nanson road. This locality is only about 6 to 8 miles inland from the Indian Ocean coastline at Coronation Beach, amidst steep and rocky flat-topped hills (mesas), which are densely covered with a unique and diverse sclerophyll heath formation (see McFarland 1977). The overall appearance of this vegetation vividly recalls certain Southern Californian coastal chaparral habitats, when viewed from a distance (a striking convergence in leaf forms and growth habits, etc.).
It is quite possible that so-called "progress" or "development" could have reared its ugly head in at least some of the habitats described herein. To the extent that this may have transpired, some of my above descriptions might now be relegated to the category of "history," and Carthaea (or its foodplants) may no longer be present in all of these locations (?).... But this paper faithfully documents the localities as they were at the time of these observations....
I must thank Julie Klein (of Hereford, Arizona) for her expert handling of this manuscript, from "raw notes" through to the trying final revisions! I also thank Ian Common and J.A. Mahon for their suggestions regarding where to look for Carthaea larvae in the Needilup to Jerramungup district, and Paul Wilson (W.A. Dept. Agric., Perth), for help, with the determinations of numerous Western Australian plants between 1968 - 1978. Pamela Cameron (if still of Ravensthorpe?) may have some interesting additional foodplant records, as she was becoming interested in Carthaea when I last visited that locality in April of 1985....
BEARD, J.S. (1969) -- Endemism in the Western Australian flora at the species level. J. Roy. Soc. W. Aust. 52(1): 18-20.
___________ (1970) -- A Descriptive Catalogue of West Australian Plants. Pub. of Soc. for Growing Australian Plants (S.G.A.P.), Sydney
___________ (1976) -- The vegetation of the Geraldon area of Western Australia (detailed map and booklet). Vegmap Publications, 6 Fraser Rd., Applecross, W.A. 6153.
___________ (1990) -- Plant Life of Western Australia. Kenhurst. N.S.W.: Kangaroo Press (319 pp.). ISBN 0 86417 2796.
BLACKALL, W.E. & GRIEVE, B.J. (1974) -- How to Know Western Australian Wildflowers, Parts 1-3 (in one vol.). Nedlands: Univ. of W.A. Press. [see also Grieve]
BLEST, A.D. (1957A) -- The function of eyespot patterns in the Lepidoptera. Behaviour 11: 209-256.
___________ (1957 B) -- The evolution of protective displays in the Saturniidae and Sphingidae. Behaviour 11:257-309.
BURBIDGE, N.T. (1960) -- The phytogeography of the Australian region. Aust. J. Bot. 8:75-212.
COMMON, I.F.B. (1966) -- A new family of Bombycoidea (Lepid.) based on Carthaea saturnioides Walker from Western Australia. J. Ent. Soc. Qld. 5: 29-36. (pdf)
C.S.I.R.O. (1970) - The Insects of Australia. Melbourne Univ. Press (1029 pp.). [see pp. 850, 854-55, 858]
COURTNEY, S. (1982) -- The "edge effect" in butterfly oviposition. Ecol. Ent. 7: 131-137.
DALLMAN, P.R. (1998) -- Plant Life in the World's Mediterranean Climates. Berkeley & Los Angeles: University of California Press (258 pp.)
ERICKSON, R., et al (1973) -- Flowers and Plants of Western Australia. Sydney: A.H. & A.W. Reed. (numerous superb color photographs from all floristic regions of the state).
GEORGE, A.S., HOPKINS, A.J.M. & MARCHANT, N.G. (1979) -- The heathlands of Western Australia. In: Heathlands and Related Shrublands of the World. (Ecosystems of the World 9A & 9B: chapters 2, 6, 7). Amsterdam & N.Y.: Elsevier Sci. Pub. Co.
GRIEVE, B.J. & BLACKALL, W.E. (1976) -- How to Know W.A. Wildflowers, Part IV. Nedlands: Univ. of W.A. Press. [see also Blackall]
HEPPNER, J. B. (2006) -- in Lepidopterorum Catalogus, Fascicle 106: 1-8 (pdf)
MAIN, B.Y. (1967) -- Between Wodjil and Tor. Jacaranda Press, Brisbane and Landfall Press, Perth [detailed seasonal/phenological account of the natural history of a locality about 100 miles E. of Perth].
MARCHANT, N.G. (1973) -- Species diversity in the southwestern flora. J. Roy. Soc. W. Aust. 56(1-2): 23-30.
McFARLAND, N. (1966) -- Overcoming difficulties with the pupae of Euproserpinus phaeton mojave in captivity (Sphingidae). J. Res. Lepid. 5(4): 249-252. [another example of the great importance of sunshine]
___________ (1967) -- Spring moths of a natural area in northeastern Kansas. J. Res. Lepid. 6(1): 1-18. [the "edge effect," as seen in Hemaris oviposition]
___________ (1970A) -- Botanical names in entomological papers and habitat studies. J. Res. Lepid. 9(2): 89-96.
___________ (1970B) -- Moth Eggs! Aust. Nat. Hist. Mag. 16(10), June issue: 346-352. [see pp. 348-49, Fig. 9, for a photo of 3 living Carthaea eggs, as oviposited on B. sphaerocarpa]
___________ (1972A) -- Notes on describing, measuring, preserving, and photographing the eggs of Lepidoptera. J. Res. Lepid. 10(3): 203-214.
___________ (1972B) -- Egg photographs depicting 40 species of southern Australian moths. J. Res. Lepid. 10(3): 215-247. [see pp. 224-225, Fig. 9, for a photo of 3 living Carthaea eggs on B. sphaerocarpa]
___________ (1973) -- Some observations on the eggs of moths and certain aspects of first instar larval behavior. J. Res. Lepid. 12(4): 199-208. [entirely Australian examples discussed in this paper]
___________ (1974) -- Notes on 3 species of Hemileuca (Saturniidae) from eastern Oregon and California. J. Lepid. Soc. 28(2): 136-141. [more documentation of the sun requirement for larval health] (pdf)
___________ (1976) -- Hilltopping and defence behaviour in a [W. Australian] diurnal agaristid moth. Aust. Ent. Mag. 3 (2): 25-29.
___________ (1977) -- Introduction to Howatharra Hill Reserve in the Moresby Ranges near Geraldton, Western Australia [32-page booklet printed by Geraldton Newspapers]
___________ (1979) -- Annotated list of larval foodplant records for 280 species of Australian moths. J. Lepid Soc. 33 (Supp. to 3): 1-71. [see pp. 19-20]
___________ (1988) -- Portraits of South Australian Geometrid Moths. Lawrence, Kansas: Allen Press (400 pp.). ISBN 935868-32-1.
MORCOMBE, M.K. (1977) -- Australia's Western Wildflowers (4th ed.). Dee Why, N.S.W.: Lansdowne Press (div. of Paul Hamlyn Pty. Ltd.).
SHAPIRO, A.M. (1984) -- "Edge-effect" in oviposition behavior: a natural experiment with Euchloe ausonides (Pieridae). J. Lepid. Soc. 38(3): 242-245.
ZAHL, P.A. (1976) -- Southwest Australia's wild gardens: bizarre and beautiful. National Geographic Mag. 150(6): 858 - 868 (Dec. issue).
Click on any photo to enlarge it.
Moth Study (CARTHAEA)
Sidetracked by Stapeliads!
HOWATHARRA HILL RESERVE
The EARLY HISTORY of HOWATHARRA HILL RESERVE near GERALDTON, WESTERN AUSTRALIA (1968-1988)
The Concept of So-Called "DEVELOPMENT"
HOWATHARRA: INTERPRETATION of the SPREADSHEET COLUMNS
HOWATHARRA HILL RESERVE: ABOUT the "ZONES" CREATED FOR DOCUMENTING LOCATIONS on the Reserve
HOWATHARRA HILL RESERVE: FLOWER COLOURS CODED
HOWATHARRA HILL RESERVE: Comments on the PHOTOS in the GALLERY
MORE PLANT DOCUMENTATION NEEDED at HOWATHARRA HILL RESERVE!
HOWATHARRA HILL RESERVE: BOTANICAL PHOTO GALLERY
FINAL COMMENT: The Fruits of "Progress"