Neotropical tineidae, VI: Prosetomorpha falcata, a new genus and species of setomorphinae (Lepidoptera: Tineoidea) from Colombia associated with curculionid galleries in stems of Solanum

15 Pages·1996·9.4 MB·

by  D R Davis

PROC. ENTOMOL. SOC. WASH.
98(2), 1996, pp. 173-187
NEOTROPICAL TINEIDAE, VI: PROSETOMORPHA FALCATA, A NEW
GENUS AND SPECIES OF SETOMORPHINAE (LEPIDOPTERA: TINEOIDEA)
FROM COLOMBIA ASSOCIATED WITH CURCULIONID GALLERIES IN
STEMS OF SOLANUM
DONALD R. DAVIS
Department of Entomology, National Museum of Natural History, MRC-127, Smith-
sonian Institution, Washington, DC 20560 U.S.A.
Abstract.(cid:8212)Adult and immature stages of Prosetomorpha falcata, a new genus and
species of tineid moth from Colombia, are described and illustrated. Prosetomorpha 1s
remarkable in being the most plesiomorphic setomorphine tineid discovered, as evidenced
by the five-segmented maxillary palpi, moderately well developed haustellum, mandibles
vestigial but distinct, female with signum present, and larva with six pairs of stemmata.
Synapomorphies shared with other Setomorphinae include similar semi-appressed head
vestiture, annulate but completely fused, eighth abdominal tergosternum in the male, mem-
branous eighth abdominal segment without rami in the female, and larvae with unidentate
mandibles. The larva is believed to be primarily a scavenger within the burrows of a
curculionid weevil, Faustinus apicalis (Faust), that bores in the stems of Solanum qut-
toensis var. quitoensis Lamarck and S. quitoensis var. septentrionale R. E. Schultes. A
braconid parasitoid, Promicrogaster sp., has been reared from burrows occupied by Pro-
setomorpha.
Key Words: Tineidae, Setomorphinae, Prosetomorpha, immatures, scavenger, host rec-
ord, Solanum, Curculionidae, Faustinus, Neotropical
In the course of their investigations on Morphological comparisons of the larva,
the insect pests of Solanum quitoensis La- pupa, and adult reveal that Prosetomorpha
marck, known locally as (cid:8220)(cid:8216)lulo(cid:8221) or (cid:8220)(cid:8216)nar- is a member of the Setomorphinae, a small,
anjillo,(cid:8217)(cid:8217) entomologists at the Instituto Col- mostly neotropical subfamily, previously
ombiano Agropecuario (ICA) of Bogota, represented by two genera (Setomorpha,
Colombia, have reared a previously un- Lindera) and approximately eight species
known, stem-boring setomorphine moth,
(Robinson and Nielsen 1993). Prosetomor-
Prosetomorpha falcata. The larva was
pha is of phylogenetic interest in being the
found frequently in association with larvae
most plesiomorphic member of the subfam-
of the stem-boring weevil, Faustinus api-
ily, as evidenced by the five-segmented
calis (Faust). Considering what is known of
maxillary palpi (Figs. 13, 14), relatively
the larval biology of other Setomorphinae
well developed haustellum, mandibular ves-
(Hinton 1956, Gozmany and Vari 1973,
tiges distinct, female with signum present
Zimmerman 1978, Robinson and Nielsen
(Figs. 24, 25), and larva with six pairs of
1993), the new species probably feeds pri-
stemmata (Figs. 35, 55). The discovery of
marily as a scavenger within the tunnels of
the weevil. Observations indicate, however, Prosetomorpha consequently broadens our
that living plant tissue is also consumed. definition of the subfamily, which previ-
174 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON
ously had been characterized in part by of maxillary palpus. Maxillary palpus 5-
moths with more reduced mouthparts and segmented, with ratios from base = 0.2:
by larvae lacking stemmata (Hinton 1956, 0.18: 0.18: 1: 0.33. Labial palpus 3-seg-
Zimmerman 1978, Robinson and Nielsen mented; ratios from base = 0.43: 1: 0.88;
1993). Synapomorphies shared with other segment II smooth dorsally and laterally,
Setomorphinae include similar semi-ap- with rough, triangular tuft ventrally; bristles
pressed head vestiture (Figs. 3, 4), slender absent; segment III entirely smooth, de-
annulate eighth abdominal sclerite with pressed.
stout projections directed anteriorly in the Thorax: Metafurcasternum (Figs. 16, 17)
male (Fig. 19), membranous eighth abdom- with anteromedial process (APM) elongate,
inal segment without rami in the female slender, with a pair of furcal apophyses
(Fig. 24), and larva with unidentate man- (FA) directed sharply anteriorly; furcal
dibles (Fig. 56). In addition to retaining the ridge continues caudally and terminates as
plesiomorphies listed above, Prosetomor- a pair of rounded lobes arising inside lam-
pha differs most notably from Lindera and ina of secondary furcal arms (LSF). Fore-
Setomorpha by the presence of | and 2 an- wing (Fig. 15) falcate, abruptly indented
nuli of flagellar scales (a basal, dorsally ab- between apex and M1; R 5-branched; R4
breviated row and an entire distal annulus and 5 stalked half their length; R5 termi-
(Figs. 5, 6), falcate forewings, and a com- nating before apex; all 3 branches of M sep-
pletely fused, eighth abdominal tergosternal arate; CuA1 and 2 arising approximate; Al
ring in the male. In other Setomorphinae and 2 fused except for fork at basal third;
the adults possess a single annulus of fla- accessory cell present; base of media usu-
gellar scales, the forewings terminate in a ally not evident within discal cell; retinac-
simple rounded apex, and the eighth ab- ulum of male a tightly curled flap (Figs. 9,
dominal sclerite of the male is interrupted 10). Hindwing with all veins arising sepa-
dorsally. rate; M 3-branched; base of media divided
within cell; male with a single stout frenu-
Prosetomorpha Davis, NEw GENUS
lum; female with 2 smaller frenular bristles.
Type species.(cid:8212)Prosetomorpha falcata, Foreleg (Fig. 11, 12, 18) with epiphysis ca.
new species. 0.5 the length of shortened tibia, the latter
Adult.(cid:8212)Moderately large moths with equal in length to tarsomere I. Tibial spurs
falcate forewings; length of forewing = = 0-2-4. Apices of all tibiae and tarso-
8.5(cid:8212)-13 mm. meres with 3 stout, spiniform setae (Fig.
Head (Figs. 3, 4, 13, 14): Vertex mod- iL 1D).
erately rough with lateral tufts converging Abdomen (Fig. 19): Sternal apophyses (cid:8212)
mesally over occiput and projecting anteri- slender, ca. half the length of S2. Eighth
orly between antennae over frons; scales segment of male with a slender, sclerotized
slender with bidentate apices. Frons rela- ring completely encircling segment; a pair
tively smooth, scales directed mesally. An- of slender projections arising laterally from
tenna simple in both sexes; length ca. % of ring; T7 reduced, triangular. A pair of non-
forewing; scape cylinrical, without pecten; retractible coremata arising ventrally from
flagellum (Figs. 5, 6) with two rows of slen- S8 of male. Corethrogyne of female con-
der scales per segment dorsally, with only sisting of a dense ring of elongate, straight
the distal row forming a complete ring. Pil- setae.
ifers well developed, densely setose. Man- Male genitalia: Tegumen reduced to a
dibles (Fig. 13) present but vestigial, narrow dorsal ring. Vinculum similar to and
equalling apical segment of maxillary pal- contiuous with tegumen as a narrow ventral
pus in length. Haustellum moderately de- ring; saccus short, ca. 0.14 the length of
veloped (Fig. 14), slightly exceeding length valva, compressed. Valva long, ca. 1.3 the
VOLUME 98, NUMBER 2 175
Figs. 1-6. Prosetomorpha falcata. 1, Adult male, forewing length 10.6 mm. 2, Female, forewing length 14
mm. 3, Head, lateral view (0.75 mm). 4, Anterior view of Fig. 3. 5, Lateral view of antenna at distal third
showing two dorsal rows of scales (annuli; 100 pm). 6, Ventral view of Fig. 5 showing continuation of distal
row of scales and position of sensilla coeloconicum (see arrow; 100 wm). (Scale lengths in parentheses; bar
scale for all photographs = Fig. 3.)
176 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON
Figs. 7-12. Prosetomorpha falcata, adult. 7, Sensilla coeloconicum shown in Fig. 6 (5 pm). 8, Ventral
sensilla of antenna showing details of sensilla chaetica (arrow) and sensilla auricillica (asterisk) (15 pm). 9,
Male retinaculum, ventral view, (120 pm). 10, Distal view of Fig. 9 (100 wm). 11, Foretibia with epiphysis and
apical spines (176 pm). 12, Detail of epiphysis showing flat spines (comb; 6 um). (Scale lengths in parentheses;
bar scale for all photographs = Fig. 7.)
VOLUME 98, NUMBER 2 NWT
length of genital capsule; sacculus moder- light to dark brown scales with suffusion of
ately broad, gradually narrowing to ex- cream around tornus. Hindwing uniformly
tremely slender cucullus (Fig. 22), bearing fuscous except for streak of white along
a small recurved spine at apex. Juxta a flat, costa, broadest at wing base and narrowing
subrectangular, elongate plate, with length toward apex; fringe generally lighter in col-
ca. 2X width. Aedoeagus a relatively sim- or, gray along hind margin becoming more
ple, slightly depressed, elongate, and slight- white toward apex with streaks of fuscous.
ly curved (viewed laterally) tube; cornuti Legs mostly dark fuscous dorsally, pale
absent. buff ventrally, with buff banding on tibia
Female genitalia: Ovipositor elongate, and more faint at apices of tibia and tarso-
telescoping. Posterior apophyses 1.7 the meres. Hindleg much paler, lighter brown.
length of anterior pair. Ventral pseudapo- Abdomen: Dark fuscous dorsally and _lat-
physes absent. Ostium bursae indistinct, erally, cream ventrally with long, cream,
broad; a small, sclerotized, triangular scler- piliform scales over A8 largely covering
ite (amella postvaginalis; Fig. 24, LP) im- genitalia.
mediately caudad to ostium; lamella post- Female (Fig. 2).(cid:8212)Length of forewing
vaginalis with a slender keel-like process 10.5(cid:8212)13.0 mm. Generally paler than male.
extending anteriorly; ductus bursae mostly Head: Light brown to white with light
broad, membranous except for a dense, brown scaling laterally on labial palpus.
elongate patch of minute spinules from an- Forewing light brown with fuscous spots
terior end that extends to signum within more evident. Hindwing gray with whitish
corpus bursae; corpus bursae moderately costal streak as in male. Legs with similar
enlarged (Fig. 24), with a single densely markings to male but generally lighter in
spinose signum (Fig. 25). color.
Etymology.(cid:8212)The generic name is de- Male genitalia (Figs. 20(cid:8212)23).(cid:8212)As de-
rived from the Greek prefix pro (before) scribed for genus.
combined with the generic name Setomor- Female genitalia (Figs. 24, 25).(cid:8212)As de-
pha. It is considered feminine in gender. scribed for genus.
Larva (Figs. 30(cid:8212)42, 49(cid:8212)58).(cid:8212)Length of
largest larva 20 mm, maximum diameter
Prosetomorpha falcata Davis,
2.9 mm. Body generally white with distinct
NEW SPECIES
dark brown plates and pinacula (Figs. 49,
Male (Fig. 1).(cid:8212)Length of forewing 8.5(cid:8212) BO):
10.1 mm. Head (Figs. 3, 4, 13, 14): Vertex Head: Maximum width 2.7 mm. Color
buff to dark brown; frons paler, cream to reddish brown, becoming darker over frons
buff. Antenna with scape mostly fuscous, and along anterior margins. Chaetotaxy as
paler ventrally; flagellum light brown, cov- illustrated (Figs. 30(cid:8212)32, 34, 52, 53, 55); AF
ered with narrow scales dorsally, mostly na- 1 absent. Stemmata (Figs. 35, 55) consist-
ked ventrally except for dense pubescence ing of 6 pairs, with 3(cid:8212)5 contiguous near
of short sensilla chaetica and dense, slender lateral rim of antennal socket, and 6 more
sensilla auricillica (Fig. 8). Maxillary pal- remote and ventral. Mandible unidentate
pus cream to white. Labial palpus mostly (Fig. 56). Spinneret (Fig. 33) slender and
cream to white with external sides of I and elongate with a minute orifice. Labial pal-
II irrorated with fuscous. Thorax: Dorsum pus 2-segmented, slender and elongate, ca.
brown, irrorated with fuscous; tegulae 0.8 the length of spinneret; apical segment
mostly fuscous. Venter pale buff to cream. less than % the length of basal segment; api-
Forewing variably light to dark brown, fine- cal seta 1.5X the length of second segment.
ly spotted with small clusters of dark fus- Apex of mentum with a pair of minute sec-
cous scales, fringe similarly mottled with ondary labial setae (Fig. 33).
178 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON
Figs. 13-19. Prosetomorpha falcata, adult. 13, Head, anterior view; mandible (see arrow; 0.5 mm). 14,
Detail of maxilla (0.2 mm). 15, Wing venation. 16, Metafurcasternum, lateral view (0.5 mm). 17, Caudal view
of Fig. 16. 18, Leg structure (1 mm). 19, Ventral view of male abdominal segments 7-8; note complete,
sclerotized ring on A8 (0.5 mm). (Scale lengths in parentheses.)
VOLUME 98, NUMBER 2 179
r
Figs. 20-27. Prosetomorpha falcata, adult. 20. Male genitalia, ventral view (0.5 mm). 21, Lateral view. 22,
Mesal view of valva. 23, Ventral view of aedoeagus. 24, Female genitalia, ventral view; LP = lamella postva-
ginalis (0.5 mm). 25, Enlarged detail of signum shown in Fig. 24. 26, Pupa, dorsal view (2 mm). 27, Ventral
view. (Scale lengths in parentheses.)
PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON
Figs. 28-33. Prosetomorpha falcata. 28-29, Adult: 28, Pretarsus of hindleg, ventral view (38 wm). 29, Detail
of unguitractor plate in Fig. 28 (12 pm). 30(cid:8212)33, Last instar larva: 30, Head, dorsal view (0.43 mm). 31, Head,
ventral view (0.43 mm). 32, Head, anterior view (0.43 mm). 33, ventral view of maxilla and labium (100 pm).
(Scale lengths in parentheses; bar scale for all photographs = Fig. 28.)
VOLUME 98, NUMBER 2 181
Thorax: Pronotum and spiracular plates 1560 m, Cundinamarica Prov.; Oct 1988, I.
dark reddish brown. Lateral setae trisetose Zenner, ex stem of Solanum quitoensis [vat.
and together with spiracle on same plate; a septentrionalis R. E. Schultes], USNM.
crescent shaped, hyaline separation imme- Paratypes.(cid:8212)Same data as holotype: 6 6,
diately anterior to spiracle (Fig. 51). Meso- 9 §, 11 cocoons, slides USNM 30429,
and metathorax with L3 arising on separate 304305930597 S059S hs SOOM ei o-
pinacula from L1(cid:8212)2. MSD1 and 2 reduced, (BMNH, ICAB, USNM); Same locality as
of similar lengths. Legs well developed; tar- holotype: 2 ¢, 2 2, May 1990, I. Zenner,
sal claw moderately stout, with an abruptly ex stem of Solanum quitoensis [var. qui-
enlarged base (Fig. 38). Coxae widely sep- toensis Lamarck, (ICAB, USNM); 13 lar-
arated, bearing 6 setae. vae, slides USNM 30599, 30600, 30677, 8
Abdomen: L1-(cid:8212)3 on separate pinacula on pupae, slides USNM 30602, 30603, 31605,
segments Al(cid:8212)8; L2 and 3 together on AQ. May 1988, ex stems of Solanum quitoensis
SV trisetose on Al-(cid:8212)8, with SV1 and 3 to- [var. septentrionalis R. E. Schultes,
gether on same pinacula on Al-(cid:8212)6. Anal (USNM).
plate with 5 pairs of setae, including extra Hosts.(cid:8212)Solanaceae: Solanum quitoensis;
seta XD1 (Fig. 51). Prolegs well developed Zenner-Polania (in corres. 6 Jun 1990) re-
on A3-(cid:8212)6 and 10; crochets A3(cid:8212)6 uniordinal, ports both the spiny variety septentrionalis
uniserial, and arranged in a complete ellipse R. E. Schultes and the smooth variety qui-
of approximately 45(cid:8212)47 hooks; a scattered toensis Lamarck as hosts.
band of smaller, numerous spines encircling Parasitoid.(cid:8212)Braconidae: Promicrogaster
apex of planta (Fig. 39); crochets on A10 sp. (det. PR. M. Marsh).
consisting of a single row of approximately Distribution.(cid:8212)Reported only from the
20(cid:8212)22 hooks along anterior edge of planta type locality in central Colombia.
(Fig. 42). Etymology.(cid:8212)The specific epithet is de-
Pupa (Figs. 26, 27, 43-45, 59-64).(cid:8212) rived from the Latin falcatus (sickled-
Length 9-11.3 mm; width 2.9-3.3 mm. shaped, hooked) in reference to the falcate-
Color usually light reddish brown, becom- tipped forewings.
ing darker anteriorly. Head smooth except Discussion.(cid:8212)Zenner-Polania (personal
for a minute, subapical, slightly curved correspondence 19 June 1989) reports that
spine projecting anteriorly and appressed to larvae of P. falcata feed within the stems
head (Fig. 45); length of spine ca. 90 jm of Solanum quitoensis, generally in groups
long. Labrum with a pair of lateral setae of 3 to 5. Sometimes they co-occur with
(Fig. 59). Forewings extending beyond cau- larvae of the stem-boring weevil, Faustinus
dal margin of A4 (Fig. 27). Hindlegs only apicalis, apparently scavenging in the de-
to middle of A3. A3(cid:8212)7 with a small anterior tritus left by the latter. In freshly damaged
row of spines and a smaller, caudal row of stems, however, Prosetomorpha larvae ap-
spines; tabulation of spines as follow: A3, pear to consume living plant tissue, thus re-
anterior = 26(cid:8212)29, posterior = 51-58; A4 sembling the broader feeding habit of a few
(Fig. 60), anterior = 43-47, posterior = Opogona (Davis and Pefia 1990). Infested
67(cid:8212)75; A5, anterior = 50(cid:8212)60, posterior = stems are typically swollen (Figs. 46, 47).
70-77; A6, anterior = 42(cid:8212)49, posterior = Damage has been observed only in plants
63-71; A7, anterior = 34(cid:8212)38, posterior = 10 months or older. After that period, even
24-28; A8 = 17-19; A9 = 9-10. A10 en- mature plants with stem diameters up to 10
circled by 8 stout spines of equal size (Figs. cm are tunneled.
61(cid:8212)64) as follow: a dorsal pair, 2 lateral Older larvae are often found exposed
pairs bearing short setae, and a ventral pair within the galleries, with younger larvae
separated further apart than dorsal pair. most frequently occurring within flimsy,
Holotype.(cid:8212)d; COLOMBIA: Anolaima, silken cases covered with frass. In the field,
PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON
Figs. 34-39. Prosetomorpha falcata, last instar larva. 34, Head, lateral view (0.46 mm). 35, Detail of
stemmatal area in Fig. 34 (150 pm). 36, Maxilla (43 ym). 37, Detail of sensilla at apex of maxillary palpus
(8.6 wm). 38, Pretarsus of metathoracic leg (43 ym). 39, Right proleg, A4 (arrow = anterior; 158 wm). (Scale
lengths in parentheses; bar scale for all photographs = Fig. 34.)