Notes on the Life Cycle of the Tobacco Hornworm, Manduca sexta (L.) (Lepidoptera; Sphingidae), in Puerto Rico

The life cycle of the sphingid moth, Manduca sexta (L.), the tobacco hornworm, was investigated in Puerto Rico. Descriptions of the stages, including measurements of the egg (length and width), larva (length and head capsule width), pupa (length), and the duration of each of the stages are given. The estimated leaf consumption by each larval instar, a list of known host plants, and the natural enemies known to occur in Puerto Rico are included.

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Life history and larval density of Cheumatopsyche digitata Mosely (Trichoptera: Hydropsychidae) in Opa Reservoir spillway, Ile-Ife, southwestern Nigeria

Zoosymposia ◽

10.11646/zoosymposia.5.1.32 ◽

2011 ◽

Vol 5 (1) ◽

pp. 401-407

Author(s):

SYLVESTER OGBOGU ◽

WILLIAMS ADU

Keyword(s):

Life History ◽

Life Cycle ◽

Larval Instar ◽

Larval Density ◽

Adult Emergence ◽

Head Capsule ◽

Southwestern Nigeria ◽

Growth Ratio ◽

Head Capsule Width ◽

Site Density

The life history and density of Cheumatopsyche digitata Mosely (Trichoptera: Hydropsychidae) were examined below Opa Reservoir in Ile-Ife, southwestern Nigeria. This caddisfly is the only species that occurs immediately below the impoundment auxiliary spillway where it closely associates with an aquatic bryophyte, Fontinalis sp. We collected larvae every month between July 2004 and June 2005 as long as larvae were available in the study site. The instar growth ratio was fairly constant and ranged from 1.198 to 1.402 (mean ± standard error = 1.285 ± 0.073) but mean head capsule width increased with larval development. The frequency distribution of head capsule width of larvae clustered into 5 size classes, suggesting 5 larval instars for C. digitata in the study site. Density of larvae ranged from 1,100 to 11,150 inds.m-2 (mean ± SE = 6739 inds.m-2 ± 3904.70), the highest densities occurring in October 2004 during the bloom of Fontinalis. The first larval instar appeared in July 2004. Adult emergence occurred mainly in December 2004 through January 2005 at the onset of reservoir draw-down and death of Fontinalis. These patterns indicate that C. digitata tended to show a univoltine life cycle in the study site.

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Life cycle of Diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), in Puerto Rico

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v70i4.7099 ◽

1969 ◽

Vol 70 (4) ◽

pp. 229-234

Author(s):

Carlos Rosario ◽

Carlos Cruz

Keyword(s):

Puerto Rico ◽

Life Cycle ◽

Body Length ◽

Plutella Xylostella ◽

Average Duration ◽

Diamondback Moth ◽

Head Capsule ◽

Head Capsule Width ◽

Larval Length

The life cycle of the diamondback moth, Plutella xylostella (L.), the worst pest of cabbage in Puerto Rico, was studied. Description of the stages, including measurements of the larva (body length and head capsule width), and duration of the stages are given. The average duration in days of the egg, larva, prepupa, pupa and adult was 3, 11.7 (4 instars), 1, 3.6 and 11.1, respectively. Larval length and head capsule width in mm for the 1st, 2nd, 3rd and 4th instar was 1.2, 2.1, 3.7, 7.0 and 0.15, 0.24, .40, 0.56, respectively.

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Life cycle and control of the Asian lime swallowtail, Papilio demoleus (Lepidoptera: Papilionidae): A new invasive pest in Puerto Rico.

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v94i1-2.2592 ◽

1969 ◽

Vol 94 (1-2) ◽

pp. 165-174

Author(s):

Alejandro E. Segarra-Carmona ◽

Irma Cabrera-Asencio ◽

Luisa E. Flores-López ◽

Luis Morales-Collado

Keyword(s):

Puerto Rico ◽

Life Cycle ◽

Larval Instar ◽

Pupal Stage ◽

Head Capsule ◽

Invasive Pest ◽

Toxicity Tests ◽

Local Conditions ◽

Larval Stages ◽

Papilio Demoleus

The arrival of the invasive Asian lime swallowtail, Papilio demoleus L., in Puerto Rico has prompted the need for a better understanding of its life cycle, and its control options under local citrus-producing conditions. Our results show that P. demoleus has a life cycle of approximately 30 days. From oviposition, eggs hatch in three days. Larval instar durations are 3, 2, 3, 3, and 5 d for larval stages 1 to 5, respectively. Pupal stage lasts approximately 12 days. Head capsule measurements for instars 1 to 4 are similar in males and females. Last instar females tend to be larger than males. Our data suggest that 12 or more generations are possible under local conditions. Acute stomach toxicity tests on third instar larvae indicate that spinosad and Bacillus thuringiensis subs, kurstaki cause 100% mortality in most concentrations tested. Other insecticides were not effective. Possible advantages of using these products are discussed in light of initiatives to use reduced risk pesticides and biologically-based pesticides.

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Breaking the rule: Five larval instars in the podonomine midge Trichotanypus alaskensis Brundin from Barrow, Alaska

Journal of Limnology ◽

10.4081/jlimnol.2018.1758 ◽

2018 ◽

Cited By ~ 1

Author(s):

Alec R. Lackmann ◽

Malcolm G. Butler

Keyword(s):

Life Cycle ◽

Larval Instar ◽

Adult Emergence ◽

Head Capsule ◽

The Arctic ◽

Larval Instars ◽

Daily Monitoring ◽

Field Samples ◽

Standard Life ◽

Capsule Size

Except for one unconfirmed case, chironomid larvae have been reported to pass through four larval instars between egg and pupal stages. We have observed a fifth larval instar to be a standard life-cycle feature of the podonomine Trichotanypus alaskensis Brundin 1966 in tundra ponds on the Arctic Coastal Plain near Barrow, Alaska. T. alaskensis has a one-year life cycle in these arctic ponds. Adults emerge in June ~2-3 weeks after pond thaw, then mate and oviposit; most newly-hatched larvae reach instar IV by October when pond sediments freeze. Overwintering larvae complete instar IV within a few days of thaw, then molt again to a fifth larval instar. Imaginal discs, normally seen only during instar IV in Chironomidae, develop across both instars IV & V prior to pupation and adult emergence. While monitoring larval development post-thaw in 2014, we noticed freshly-molted T. alaskensis larval exuviae a week or more prior to any pupation by that species. In 2015-16 we reared overwintering instar IV larvae from single pond sources, individually with daily monitoring, through molts to instar V, pupa, and adult. Some overwintering instar II and III larvae were reared as well, but were few in number. During 2016 we also reared T. alaskensis progeny (from eggs) through instar II, thus documenting head capsule size ranges for all five instars in a single pond’s population. Without individual rearings, the fifth larval instar was not readily apparent for two reasons: 1) The molt itself occurs immediately after thaw and is so synchronous it is difficult to discern in daily field samples. 2) The head capsule size increment between instars IV-V is much lower than the ratio predicted by the Brooks-Dyar Rule. Up through instar IV, the Brooks-Dyar ratio for T. alaskensis ranged 1.30-1.61, but during the IV-V molt head capsule dimensions (sexes pooled) increased by a ratio of 1.09 – comparable to the magnitude of sexual dimorphism in head capsule size within each of the final two larval instars. Individual rearings coupled with 2014-2016 field surveys in nine other ponds suggest that five larval instars is an obligatory trait of this species at this location. As this is the first confirmed case of five larval instars in a chironomid, the phylogenetic uniqueness of this trait needs further investigation.

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Differentiation of roles of chemosensory organs in food discrimination among host and non-host plants by larvae of the tobacco hornworm, Manduca sexta

Physiological Entomology ◽

10.1111/j.1365-3032.1987.tb00765.x ◽

1987 ◽

Vol 12 (4) ◽

pp. 387-398 ◽

Cited By ~ 51

Author(s):

GERRIT DE BOER ◽

FRANK E. HANSON

Keyword(s):

Manduca Sexta ◽

Host Plants ◽

Tobacco Hornworm ◽

Chemosensory Organs

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Incorporation of Radiolabeled Tyrosine, N-Acetyldopamine, N-β-Alanyldopamine, and the Arylphorin Manducin into the Sclerotized Cuticle of Tobacco Hornworm (Manduca sexta) Pupae

Zeitschrift für Naturforschung C ◽

10.1515/znc-1984-11-1212 ◽

1984 ◽

Vol 39 (11-12) ◽

pp. 1066-1074 ◽

Cited By ~ 40

Author(s):

Lothar Grün ◽

Martin G. Peter

Keyword(s):

Manduca Sexta ◽

Larval Instar ◽

Tobacco Hornworm ◽

Insoluble Fraction ◽

High Loss ◽

Tyrosine Residues ◽

Cuticle Sclerotization ◽

Larval Serum Protein ◽

Pupal Cuticle

Abstract Radiolabeled manducin, which is the arylphorin (i.e. tyrosine-rich larval serum protein) of the tobacco hornworm Manduca sexta was prepared by in vivo biosynthesis from [U-14C]-ʟ-tyrosine. In order to see whether manducin is incorporated into the cuticle of developing pupae and participates in cuticle sclerotization, the radiolabeled protein was injected into late last larval instar larvae. Fractionation of the sclerotized pupal cuticle into a buffer soluble, acid soluble and acid insoluble fraction shows that up to 2.6% of peptidic tyrosine residues end up in the acid soluble portion. Another 0.5% are recovered from the acid insoluble fraction by combustion. Only 30% of peptidic tyrosine residues of manducin incorporated into the acid soluble fraction are recovered as tyrosine. The presence of radioactivity in the acid insoluble fraction suggests that peptidic tyrosine residues are transformed partly into melanin-like material. The incorporation of manducin into the cuticle of pupae is also evident from immunological studies. Relative large quantities of radiolabeled acid insoluble melanine like material is also recovered from sclerotized cuticle after incorporation of radiolabeled tyrosine as well as tanning substrates N-acetyldopamine and N-β-alanyldopamine. Application of doubly labeled [7-3H,8-14C]-N-acetyldopamine shows a high loss of 3H in the acid insoluble fraction. It is suggested that tanning agents form lignine-like polymers and that sclerotization results from copolymerization with peptidic tyrosine residues in the cuticle. Thus, the arylphorin manducin appears to be an important constituent of the sclerotization system in Manduca sexta.

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