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firmer pistils ; for all the parts which are representative of
the other species of Pronuba are here more stout, and the
denuded and flattened body is well suited to creeping
between the flowers.* There is no question but that the
tree Yuccas represent an ancient type of our flora, and
Pronuba aynthetica may also be looked upon as an ancient
type of our Lepidopterous fauna. That it should have so
many striking peculiarities that recall insects of other
orders, is, therefore, very suggestive. I was very anxious
to obtain the larva and chrysalis of this species, and the
following year Mr. Eoebele, at my request, revisited the
tree Yuccas and succeeded in May, 1888, in obtaining
infested fruit. As soon as this was received, the
larvsB left the pods and entered the ground, some of them
forming cocoons almost identical in appearance with that
of yuccasella. Others remained in the larva state, without
forming cocoons. Indeed, one peculiarity noticeable was the
great length of the larval life, as a few had not yet formed
their cocoons by the end of 1889, or more than a year
from the time they were received, while one was living and
unchanged, in its cocoon, in August, 1891, or nearly two
years and a half from the time it left the fruit. However,
most of those that were reared to the imago state, whether
by Mr. Eoebele in California or at Washington, issued the
following March or April. These facts would indicate that
while normally the moth is produced the ensuing year, yet
belated individuals may not issue from the ground until the
second or even the third year, and I have been informed
that it is not an uncommon thing for Yucca h^evifolia to
produce no flowers over large districts during some years.
The tendency to retardation in development is, under these
circumstances, advantageous to the species.



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144 HI880UBI BOTANICAL GARDEN.

Larva (PI. 41| Fig. 2, a). — Length when fall-grown, 14 mm.
Somewhat more cylindrical than that of yuccasella, the general color
being blaish-green tinted with a rosaceous hne; otherwise nndistin-
guishable from those of the other two species.

Chrysalis {PL 41, Fig. 2» 5,e). — In size » general shape and arrange-
ment of the spines similar to that of yuccaseUa, but readily distinguished
by the wing-sheaths in both sexes reaching only to the sixth abdominal

1'oint and the posterior legs to the seventh, whereas in yuceasella the
ormer reach to the eighth and the latter to about the middle of the
ninth. The medio-dorsal spines are also longer, more prong-like and less
spatulate, while the capitate spine is perhaps less prominent. The dif-
ference is more particularly noticeable in the greater length and promi-
nence of the two spines on the second abdominal joint. The anal joint
in the male is narrower and comparatitvely longer, and the two terminal
teeth much shorter than in the female, also not so well defined as in
yuceasella. The anal segment in the female is broader and stouter than
in yuccaaeUaf with the teeth shorter, stouter and further apart, (c, d, e,

Imago (PI. 41, Fig. 1, a). — Expanse 9, 15-20 mm.; ^ 16-18 mm.
Body flattened, plceous. Wings smolcy-gray; the scales sparse and as
easily lost on the upper surface, especially of primaries, as In the Sesildae,
so that none but those carefully killed soon after issuing from the chrysalis
show the wings well covered. In such specimens the general color is
cinereous, the primaries but slightly darker than secondaries, the scales
being narrow and elongate, mostly gray, but with an admixture of black
ones. The exposed membrane of the wing is fuliginous except a nar-
row dlscal space and more or less of the costal region which remain
sordid white. Fringes paler but sparse and easily lost except at anal
angle of hind wings, where they persist. Veins black and strong. Body
but sparsely clothed in freshest specimens and soon becoming bare
except at neck; highly polished and minutely punctate, and in some
specimens with metallic tendency. Head (Fig. 1, &) with the hair pale
ferruginous; eyes brown, naked; labial palpi bownlsh-black with sparse
white scales; maxillary tentacles stout and brown, shorter than tongue;
max. palpi nearly as long as tentacle, basal joint stout, rounded, joints 2
and 8 short, sub-equal in length, joint 4 very long, terminal joint with
two spines at tip; tongue very stout, long and ferruginous; antennae
black. Thorax with two singular transverse-ovoid translucent and
somewhat opalescent spots recalling the so-called cenchri of Tenth-
redinids ; legs stout and dark, the hind tibiae and tarsi pale ferruginous.
Abdomen separated from thorax dorsally by a broad and deep suture
which is pale rufous by contrast with the general plceous color; anal
joint (PI. 42, Fig. 1, c, d) in 9 rufous, with darker shade at base,
the sides compressed from above smd expanded into a broad and angu-
late wing, the borders of which are thickened and stiflEened and con-
verge to a rather sharp tip which is, however, obliquely truncate from
the side; ovipositor Issuing generally at right angles and with the same
parts as in yuceasella but all stouter and shorter (e,f). In the ^ the
dorsal fulvous suture or pit between thorax and abdomen is more pro-
found and concave, the abdomen is less flattened and the claspers are
brown, very stout, one-half as Ions; as the abdomen, the basal part
broad and leaf -like, the terminal part abruptly curved upward, dilated
into a decurved triangular tip, and the prong quite long, slightly curved
and denticulate at tip (a, d).

Described from 28 9 ?, 10 c?c?, from the fruit of Tucca hreoi^
folia.



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TUCCA MOTH AND YUCCA POLLINATION. 145
THE SPECIES OF PRODOXUS.

It is my design to give here descriptions of all the species
80 far as known. The early stages of these different species
are remarkably similar and it is extremely difficult — at
times quite impossible — to point out characters by which
to separate them. It will be well, therefore, first of all to
reproduce the original description of Prodoxus decipiens^
somewhat amplified, and merely describe the others by
comparison. The ovipositor varies in appearance according
as it is extruded or not.

Generic Characters of Prodoxus.

IMAOO. — Agreeing with Pronnba, except In the following important
particulars: The basal joint of the maxillary palpi in the female Is not
produced into a spinous tentacle, but is formed just as in the male, being
a mere blunt-pointed tubercle.

Larva. — Apodous.

Chbysalis. — Without prominent dorsal spines.

PRODOXUS decipiens Riley,

[PI. 39, Figs. 1, 2, 3, 4.]

Eoo.— Soft, white, easily yielding to pressure, and hence variable In
shape, but usually elongate, rounded at both ends about O.i mm. in
length, and less than 0.1 mm. wide.

Larva (PI. 89, Fig. 1, a).— Length 5 to 7 mm. Apodous, plump,
broadest on joints 2 and 8, tapering thence posteriorly, with the dorsum
strongly arched and the bead and prothoracic joint more or less fully
bent down on the breast. The body is glabrous and not conspicuously
wrinkled and the general aspect strongly recalls some Hymenopterous or
Rhyncophorous larvss. Head small, retractile. Stigmata placed as in
Pronuba, i, e., the first pair on the hind portion of the prothorax and
rather lower down than the succeeding 8 pairs, which are on the anterior
portion of joints 4 to 11, the prothoracic spiracles somewhat Jargerthan
the rest. Color of body either pale yellowish- white, or emerald -green,
this last being the more usual color of the mature and especially of
the hibernating specimens. The head is honey-yellow with a dusky spot
on each side, a dash on each suture of the epistoma, the mouth dark
brown, the mandibles black, labium and maxillra white; the mandibles
have four teeth, much blunter than in Pronuba, though the labial palpi
are smaller and more plump and the labium and maxillae do not surpass
the mandibles. The cervical shield is not defined as in Pronuba, but
consists of 4 chitinous patches of the same color as the head.

Chrtsaus (PI. 89, Fig. 1, e). — Average length about 6 mm. Of
the same color as In Pronuba but much more slender, with the dorsum
less arched and lacking the characteristic dorsal, arcuated plates with
their peculiar recurved, flattened spines, there being In place of them the
barest indication of a transverse row of minute points or teeth not re-

10



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146 MISSOURI BOTANICAL GARDEN.

curved but pointing posteriorly, near the anterior border of Joints 6-11;
joint 5, which is so strongly aimed in Pronuba, being here perfectly
smooth. Joint 12 in both sexes is unarmed as in (^ but not in the S
Pronnba, while the terminal subjoint is much swollen and curved upward,
with two minute spines taking the place of the broader, compressed
processes in Pronuba. The capitate point Is much stouter and beak*
like, flattened and somewhat excavated laterally, so that the upper edges
form each a sharp carina. The sexes are only distinguishable by the
somewhat less swoolen sub-ioint in the 9 and her longer leg-sheaths,
which reach a little beyond the tip of the body, whereas in the J^ they
fall short of the tip.

Imago 9 , (Fig. 2). Average expanse 16 mm. In general appearance
closely resembling Pronuba vuceaaella, but the upper surface is ordi-
narily more silvery and less creamy in appearance, and the dark
shades, as of the eyes and the dark hairs of the palpi, front legs and tarsi
and at the base of the costs on primaries, are more pronounced and black-
ish. The under surface is somewhat darker, and the tip of the abdomen
not truncate but pointed, and slightly beveled off superiorly. The
terminal joint is swollen and darker than in Pronuba. The ovipositor
is stout, dark brown, laterally flattened, between three and four times as
broad as in Pronuba, shorter, the sculpture of basal portion closer, finer
and ribbed, the tip obliquely cut off below and having a series of minute
teeth, the ventral one being more conspicuously produced, and a series
of eight or nine more prominent teeth along dorsal edge, while two dis-
tinct grooves run along the whole length and several smaller ones are
noticeable near the tip. (Fig. 8, a, d.)

(^, Somewhat smaller than Q , the genitalia being more elongate and
prominent than in Pronuba, tne claspers extending fuliy twice as far,
less recurved, and having on the lower border i small black points or
tubercles, equidistant from each other. (Fig. 8, /, g.)

Described from namerous specimens of both sexes,
either foand in the flowers or reared from the stems of
different species of Yucca throughout the eastern States.

AH the specimens obtained or reared east of the Missis-
sippi have been immaculate, with the faintest tendency to a
few minute spots; but western forms, especially those from
Texas and Colorado, show a greater tendency to maculation,
the number of spots ranging from 1 to 5 or more, usually
arranged along the middle in the form of a broad W, a dot
representing each angle and each outer tip. When the
basal spot alone is absent the four remaining present the
figure of a rhomboid. When it is absent and there is
another spot posteriorly we have the W inverted. When a
single spot is present there is no regularity in its position,
and it may be differently placed on the two opposite wings
of the same specimen. There may also be more spots on
one wing than on the opposite one, while I have seen speci-
mens with the thorax spotted with two metathoracic mesial



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YUCCA MOTH AND YUCCA POLLINATION. 147

spots, one above the other* When there are more than
five spots, the additional spots are ranged around the pos-
terior border. These spots are sometimes so small as to be
eonfined to a single scale.

FBODOXUS HARGINATUS Bilej.
[H. 43, Fig. 2.]

This species was described in 1880 (Proc. A. A. A. S.
Vol. XXIX.) from specimens collected by Mr. H. K. Mor-
rison in Kern Co., Calif. I have since been able, through
Mr. Eoebele's collecting in 1886, to rear it from the peti-
oles and basal portions of the pods of Yucca whipplei
obtained in Lios Angeles Co., Calif., in the flowers of
which it is also frequently met with from the end of April
to the end of June. Its habits, so far as they have been
observed, are quite similar to those of dedpiens^ the larvsB
remaining within the petioles nearly a year, transforming
and issuing during the ensuing month of April. No especial
observations have been made on the method of oviposition
And the egg has not yet been obtained.

Larva. — Average length 8-4 mm. General color pale bluish-green.
Head honey-yellow, marked each side of the clypeos with some more or
less distinct but Irregular dusky patches. The ceryical plate con-
colorous with the body, but marked in front and behind with two faintly
dusky patches, otherwise agreeing precisely with P. dedpiens.

Chrtsajjs. — Except in the smaller size and less prominent spines and
sculpturing, agreeing exactly with that of deetpiena. This is especially
true of the male chrysalis. The frontal tubercle in the female, besides
being smaller, lacks the sharp lateral carin^e and has on the sides a shal-
low longitudinal channel or depression. The dorsal tubercles on the
eighth abdominal joint are also transversely ovoid instead of being per-
fectly cylindrical at the base.

Imago (PL 48, Fig. 2).— Expanse 8-10 mm. Color white, the clothing
of body very sparse, especially on the abdomen, and showing more or
less distinctly the integument which is dark brown often with an »neous
tinge. Antenn® bare towards tip and yellowish. Primaries ( Fig. 2, pr)
satiny -white with a terminal black band of varying width; under surface
fuscous, almost black on costil and posterior borders; fringes white.
Secondaries white with a broad costal and apical fuscous shade; under
surface concolorous; fringes white. Apical abdominal joint of 9 black*
Ish) slender, very obliquely truncate above, the tip blunt-pointed (Fig. 2,
a). Ovipositor short and stout; the homy terminal joint gradually
narrowed to the pointed tip, the upper edge very floely and acutely
«errulate (Fig. 2, $Jo\ (Haspers of > (Fig. 2, c) not dentate, their
form much concealed by scales, the large arms broad and of nearly
uniform width; large upper basal piece obtusely angulated in the middle.



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148 MISSOURI BOTANICAL GARDEN.

Described from 21 $ $ and 22 ^ ^ collected and reared in
Southern California.

The males are as a rule smaller than the females with the
marginal band often much narrower, sometimes reduced
to a small dot or even entirely wanting.

PRODOXUS INTERMEDIUS Silej.
[PI. 48, Fig. 1.]

This species was described in the same paper as the pre-
ceding from two female specimens taken by Mr. J. Boll in
Texas and one taken by myself July 18th, 1887, at Ute
Pass, Colo. No others have been taken since, and the early
states and the male remain unknown. This species is very
interesting as showing how closely, except in lacking the
characteristic maxillary teutacle, the species of Prodoxus
may come to the t}rpical Pronuba. The character of the
ovipositor in this Prodoxus would indicate that the species
breeds perhaps normally in the fruit, notwithstanding it can
have nothing to do with pollination. It would thus be en-
tirely dependent for its existence on the efforts of Pronuba.

Imago (Vh 48, Fig. 1), 9* — S^&i^ao ^^-^ ™™* Coloration as in
Pronuba yuceaaella. Basal joint of the maxillary palpi not provided with
a tentacle, but having a slight tubercle at the tip. Apical joint of
the abdomen (Fig. 1, a) shaped as in Pronuba yuccasellaf but slightly
deeper and possibly a little thicker. Ovipositor, shaped as in Pronuba
yuccasellaf but slightly stouter, more acuminate at tip and with the
serrations of membrane finer and more numerous (tjo). The sculpture
of basal joint shows like very fine punctatlons in angular rows (bjo).

Described from 2 $ $ from Texas and 1 $ from Ute Pass,
Col., July 18, 1887.

PRODOXUS ciNEREUS Riley.

[PI. 43, Fig. 4.]

Originally described in the same paper as the preceding
from seven males collected in Eern Co., California, by Mr.
Morrison. Since that time I have obtained numerous
specimens either from the flowers of Tucca whipplei^ in
Los Angeles Co., California, collected by Mr. Eoebele, or
reared from the flower stems of the same species of Yacca*



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YUCCA MOTH AND TUCCA POLLINATION. 149

The species prefers the mam stem of the plant for purposes
of oviposition. Stems, received ia May, 1887, gave forth
the moth during the latter part of that month, but others
issued from the same stems during the same month of May
in the consecutive years of 1888, 1889 and 1890, thus
indicating great variation in the development of the species
and a remarkable tendency to retarded development. The
eggs and the early states have not been observed, nor the
earlier states preserved and described.

IMAOO ^. — Expanse 12 mm. Head, thorax, legs and apical ventral
joints wmtish. Primaries ashy; secondaries and nnder surface of all
the wings brown with a cinereous reflection. Tip of maxillary palpi and
apical third of antenn» black; the integument of body black. Claspers
(Fig. 4, a, b) dark testaceous, similar In form to those of dedpiens
but without teeth; large upper basal piece broadly rounded or 8ubtrun«
cate; the smaller piece beneath it of similar shape.

9 showing no difEerenoes whether as to size or coloration of scales, the
head being somewhat darker, on the average. Anal joint of same form
as in dedpiens, the ovipositor being more slender than in any of the other
species of the genus and coarsely toothed along the entire upper edge.

Described from many specimens.

FRODOXUS JENESGENS Rilcy.
[PI. 48, Fig. 8.]

This species was also described in the same paper as the
preceding from 8 females and 8 males collected by Mr.
Morrison, in Eem county, California, but I have since
reared it from the main stems of Yucca tohippleif also
collected by Mr. Eoebele, at Newhall, Los Angeles Co.,
California. The egg and mode of oviposition have not yet
been observed, but Mr. Eoebele reports that the larger
larv8B (doubtless those which produce females) work in the
stem with the head upward, while the smaller larvae work
downward, and that they go through their transformations
in the month of May. I have serious doubts whether there
is any sexual difference in the position of the larvsd in the
stem, as might be gathered from his observation.

Larva. — Attaining a length of 9 mm. with a diameter of only about )
the length, and distinguished from the other species by this greater
slendemess and relatively greater length. The body tapers but little
posteriorly and the general aspect is more that of a Cerambycid larva



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150 MI880UBI BOTANICAL OABDEN.

than of a BhTncophoroos larva. Qeneral color pale greenlah. Head
honey-yellow, darkest In front with a broad browniah anterior border,
more or less dlstinctyand a narrow blackish lateral line and dnsky mark-
ings each side of the clypeus, thus resembling that of P. mafyinaCiw.
The cervical shield with two or three more or less continent faintly dnsky
spots anteriorly and 2 rather well defined somewhat qnadrate black spots
posteriorly.

Chrysalis. — Scarcely dlstingalshable from that of dsdpienif except
by the smaller size, smaller spineSi and finer scolptorlng. The frontal
tubercle Is relatively shorter and stonter.

IMAOO. — Expanse, 9 1^-7 mm.; ^ 11.S— 14 mm. General color^
broDzy, the primaries with a distinct purple reflection. Under surface
of thorax, the cox» and the femora clothed with white scales. Head
whitish, with scattered black hairs; labial palpi with black hairs; 4th
and ftth Joints of maxillary palpi and the antenn», except at the base»
black, integument black. Apical abdominal joint (Fig. 8. a) swollen
as in P. dedpieiiM and obliquely truncate from above, but the tip Is also
truncate from beneath and the lower border is slightly excavated.
Ovipositor short and stout, very broad; the upper border of the homy
terminal Joint (Fig. 8, tjo) thbi, arched and finely serrate, the tip
obliquely truncate beneath and at the base of the truncation f ormlns a
small, thin tooth, the base beneath forming a blunt tooth, the border be-
tween these teeth retuse. Claspers of ^ (Fig. 8, e) with no teeth on the
arms beneath ; the arms more slender than in cinereu9 and narrowed more
abruptly near the base; the broad basal part with a small tooth at the
apex within. Large upper basal piece forming a stout process at the »pex.

Described from 20 females and 38 males taken from
Southern California, many of them reared from the main
stem of Yucca tohipplei.

FBODOXUS PaLYEBULENTUS, n. Sp.

I have five specimens of this species , all females, two of
them reared from the seed-pods of Tucca whipplei in May,
1886, by Mr. Eoebele, the pods obtained at Santiago, Cal-
ifornia, while three specimens were given me by President
H. W. Harkness, and Mary E. Ciirran, of the California
Academy of Science, in April, 1887, and obtained from
the flowers of the same Yucca. The adolescent states
are still unknown.

Imago $. — Expanse 9-10 mm. General color, white; head with the
antennn white, the basal half fuscous; eyes brown; palpi pale yellow -
ish,hairs white. Thorax, with the hair mixed with a few blackish scales ;
primaries white, more or less densely sprinkled with blackish scales at
the posterior third and sparsely so on the remaining portion. These
dark scales produce a powdery appearance of the wings, the amount
varying in the specimens before me, there being In two of them but a faint
trace of the darker scales; secondaries white, with a broad dusky
anterior margin; under surfaces more densely flecked with blackish
scales and hence somewhat darker. Abdomen fuscous above, with a few
long whitish hairs on the terminal two joints; venter and legs white.
Tip of the abdomen shaped as In P. marginatua.



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TUCCA MOTH AND YUCCA FOLLINATIOH. 151

PBODOXUS T-INVEBfiUS, D. Sp.
[PL 48, Fig. 6.]

Specimens of both sexes of this species were reared from
parts of a pod of an unknown species of Yucca (but doubt-
less T. baccala) received from Mr. D. C. Chapman, of
Washington, D. C, who had obtained them in May, 1883,
from New Mexico, the moths issuing during May of the
following year. The larvae infest the fleshy portions of
the pod and produce hard, gall-like swellings. The cocoon,
which, as with the other species, is constructed within the
burrow, is pale brownish, and resembles an elongate, cylin-
drical bag, rounded at the base and cylindrical at the apex.
When ready to transform, the larva retires to the lower third
of the bag and separates it from the upper two-thirds by a
dense, tough, delicate whitish layer of silk, thus dividing
the cocoon into two unequal chambers. No larvae were
preserved, but those which were noticed in cutting open the
swellings showed a remarkable resemblance to those of
decipiens. The chrysalis also has not been studied.

Imago. — Q. Average expanse 14 mm. ^ 10-12 mm. General color
white. Head, thorax, legs and abdomen white beneath, the hairs
between the antenne occasionaUy yeUowish. Eyes black; palpi white;
tip of labials yellowish; tongue pale yellowish. Primaries (Fig. 6, a)
marked with black as follows — a costal streak along the basal half,
widening posteriorly and more or less completely fused with a round spot
near its end. An elliptical or roundish spot about the middle of the
wing at the basal third ; a more or less sharply defined inverted-T-shaped
band across the posterior third of the wing, with Its exterior arm
generally connected posteriorly with a black patch which extends
along the posterior border but is more or less broken at the extreme
border and also along its inner margin. This terminal dark patch
usually broadens toward the apex and is sharply cut off on the costa at
about the outer fourth of the wing. Secondaries pale yellowish, darkest
at apex; fringes concolorous. Undersarfaces with the dark markings of
the primaries less sharply defined. Abdomen, brownish above, the
male claspers (Fig. 5, 6, c), yellowish-brown, almost bare, quite slender^
andgradnally narrowing toward the tip, which is almost acute; each
arm is provided with 5 or 6 very small, cylindrical, acute teeth at the
posterior edge; basal lobes are almost circular and concave at the
inner side; upper basal plate triangular. Anal segment of the female


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