Morphometric and Chronobiological Assessment of the Life Cycle of Eudocima materna

Int. Jr. of Contemp. Res. in Multi. Volume 4 Issue 1 [JanFeb] Year 2025 245 © 2025 Hafssa Chahbane, Khalid Houssaini. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC BY NC ND). https://creativecommons.org/licenses/by/4.0/ Research Article Morphometric and Chronobiological Assessment of the Life Cycle of Eudocima materna Komal Jagzap 1*, Prof. Dr. Yasmeen Shaikh 2 1,2 Dr. Rafiq Zakaria College for Women, Aurangabad, Maharashtra, India Crospondin author: Komal Jagzap Email: komaljagzap1[email protected] Corresponding Author: *Komal Jagzap DOI: https://doi.org/10.5281/zenodo.17485992 Abstract Manuscript Information The present investigation elucidates the morphometric and chronobiological dynamics of the developmental stages of Eudocima materna (Lepidoptera: Erebidae) under controlled laboratory conditions. The study integrates quantitative morphometric measurements and time-based developmental observations across egg, larval, pupal, and adult stages. The total life cycle was completed within 32.40 ± 0.79 days. Progressive allometric growth, distinct instar-specific differentiation, and a synchronised developmental rhythm were observed. The larval phase, encompassing five instars, exhibited exponential increases in mass, length, and head capsule width. Pupation marked a phase of histogenesis and structural reorganization, while the adult stage displayed notable sexual dimorphism in morphology and lifespan. The findings contribute to a refined understanding of the species’ life-history strategy, supporting ecological modeling and pest management frameworks involving E. materna. ▪ ISSN No: 2583-7397 ▪ Received: 19-01-2024 ▪ Accepted: 07-02-2024 ▪ Published: 28-02-2025 ▪ IJCRM:4(1); 2025: 245-248 ▪ ©2025, All Rights Reserved ▪ Plagiarism Checked: Yes ▪ Peer Review Process: Yes How to Cite this Manuscript Chahbane H, Houssaini K. Breaking Barriers: Digital Activism’s Role in Changing Morocco’s Political Landscape. International Journal of Contemporary Research in Multidisciplinary. 2025;4(1): 245-248. KEYWORDS: Eudocima materna, life cycle, morphometry, development, Lepidoptera, chronobiology, growth pattern 1. INTRODUCTION The genus Eudocima (Lepidoptera: Erebidae) represents a group of fruit-piercing moths of considerable ecological and economic relevance, particularly across tropical and subtropical regions. Eudocima materna, a widely distributed noctuid, is known for its frugivorous adult stage and polyphagous larval behavior. Understanding its life cycle parameters and morphometric transitions provides essential insight into its adaptive strategies and pest management potential. Developmental duration and body metrics serve as reliable indicators of physiological and environmental responses in Lepidoptera. The integration of morphometry and chronobiology offers a powerful approach to quantify stage-specific growth patterns and temporal regulation mechanisms. Prior research has outlined broad aspects of Eudocima biology (Ali & Rizvi, 2009; Singh & Rani, 2017), but a comprehensive life cycle assessment integrating both morphometric and temporal data remains limited. This study aims to fill that gap by detailing each developmental phase of E. materna under controlled rearing, providing valuable data for both ecological modeling and applied entomology. 2. MATERIALS AND METHODS Laboratory cultures of E. materna were established using fieldcollected adults maintained under controlled conditions (27 ± 2°C, 70 ± 5% RH, and a photoperiod of 12L:12D). Eggs were Int. Jr. of Contemp. Res. in Multi. Volume 4 Issue 1 [JanFeb] Year 2025 246 © 2025 Hafssa Chahbane, Khalid Houssaini. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC BY NC ND). https://creativecommons.org/licenses/by/4.0/ collected from ovipositing females and monitored for developmental progression. The larvae were reared individually on fresh host leaves to prevent cannibalism. Each instar was identified based on ecdysis and head capsule width (HCW) measurements. Morphometric parameters, including body length, width, and mass, were recorded using a stereomicroscope and analytical balance. Durations of each stage were documented daily, with data expressed as mean ± standard deviation (SD). Statistical comparisons across instars were made using ANOVA, followed by post-hoc tests to determine significant differences (p < 0.05). Pupal and adult parameters were similarly recorded, and adult longevity was observed separately for males and females. 3. RESULTS AND DISCUSSION The complete developmental cycle of E. materna extended for approximately 32.40 ± 0.79 days (Table 4.9). The egg stage lasted 2.75 ± 0.12 days, with embryos exhibiting uniform pigmentation before hatching. The larval phase, extending over 15.61 ± 0.48 days, represented the most dynamic period of growth, divided into five morphologically distinct instars. First instar larvae (2.15 ± 0.02 days) were minute and translucent, measuring 4.42 ± 0.33 mm in length and 0.0011 ± 0.0012 g in mass. Subsequent instars exhibited exponential increases in size and mass, with second instars initiating active feeding and achieving a head capsule width (HCW) of 0.76 ± 0.09 mm. By the fifth instar, larvae reached 52.02 ± 1.10 mm in length and 1.418 ± 0.091 g in body mass, indicating maximum somatic growth. The pronounced rise in HCW across instars supports Dyar’s rule of geometric growth. Larvae exhibited a characteristic wandering phase before pupation, marking the onset of histolysis and tissue reorganization. The pupal stage, lasting 13.85 ± 0.15 days, was defined by significant internal restructuring, producing robust, obtect pupae averaging 25.31 ± 0.72 mm in length and 1.328 ± 0.078 g in mass. The head capsule width (6.42 ± 0.08 mm) reflects cephalic differentiation and neural restructuring. Adult emergence was synchronous and sex ratio-balanced. Males exhibited a lifespan of 23.15 ± 0.65 days, while females survived for 25.28 ± 0.59 days. Males were relatively slender with elaborate antennae, reflecting enhanced chemosensory adaptations. Females displayed greater body mass and extended longevity, which are advantageous for oviposition and fecundity. The marked sexual dimorphism underscores the adaptive divergence of functional morphology between sexes. Table 1: Assessment of the Life Cycle of Eudocima materna Int. Jr. of Contemp. Res. in Multi. Volume 4 Issue 1 [JanFeb] Year 2025 247 © 2025 Hafssa Chahbane, Khalid Houssaini. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC BY NC ND). https://creativecommons.org/licenses/by/4.0/ Duration for Life Stages of Eudocima materna Comparatively, the duration of each developmental phase aligns with observations made for other tropical noctuids, though the rapid larval growth rate of E. materna may reflect its dietary plasticity and thermal adaptation. Similar growth dynamics have been recorded in related genera, supporting the hypothesis that temperature and nutrient availability act as principal drivers of developmental rate (Zar, 2010). The synchronization between morphometric expansion and developmental timing in E. materna suggests a tightly regulated hormonal cascade, likely governed by the interplay between ecdysteroid and juvenile hormone. Such regulation facilitates precise molting cycles and ensures optimal body proportions for subsequent stages. The transition to the pupal stage indicates energy reallocation from feeding to metamorphic restructuring, culminating in adult emergence. The observed dimorphism between the sexes may be attributed to evolutionary optimization—males prioritizing mate-location efficiency and females emphasizing reproductive investment. These findings emphasize the importance of integrating morphometric profiling with chronobiological assessment to predict phenological trends and assess species adaptability under environmental variation. This study thereby establishes baseline data for further physiological and molecular investigations on lepidopteran developmental regulation. 4. 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