The caste developmental pathway for the production of soldiers and nymphs in termite colonies is variable among species and limited numbers of studies have properly categorized such pathways. In this study, the developmental pathway for the production of soldiers and nymphs in Coptotermes formosanus Shiraki has been re-analyzed using the data from previous studies in light of new observations. Five distinct colony life stages were determined based on the caste developmental pathway used by the colony at each stage, which we here redefined as: incipient colony, immature colony, juvenile colony, mature colony, and senescent colony. We determined that in incipient colonies, the first soldier (nanitic) emerges from a second instar larva. We suggest that the production of a nanitic soldier is cost-effective as it allows the colony to focus on the production of workers from the first cohort of individuals. However, in an immature colony, the origin for the production of soldiers shifts to first and second instar workers. In juvenile colonies, soldiers are essentially produced from second instar workers. In mature colonies (>5 years), soldiers are mostly produced from second instar workers, occasionally from third instar workers, and we suggest that nymphs are primarily produced from second instar larvae. Finally, in senescent colonies, the absence of brood leads to the accumulation of old individuals. We concluded that descriptions from previous studies may have overlooked the group dynamics within a colony and that the caste developmental pathway in C. formosanus is dependent on the age of the colony.

Colony age-dependent pathway in caste development of Coptotermes formosanus Shiraki

The existence of a worker caste in Prorhinotermes inopinatus was determined with the help of biometrical analyses and morphological observations. No dichotomy between alate and worker lines was detected among the young larval instars. Mandible sclerotization and wear show that the larvae become active by the fourth instar in mature colonies, and by the third in incipient ones. Prothoracic finger-shaped expansions characterize the most dependent larval instars. The antennal structure is the best feature for distinguishing late instars. The developmental schema is very flexible: the late larvae of stages 5 to 8 (at least) can give rise to wing-padded nymphs, to the next larval instar, to presoldiers, or most likely to neotenic reproductives as well; the wing-padded individuals (nymphs) normally moult direct to alates, but they can also undergo a regression of their wing pads and revert to worker-like individuals or differentiate into soldiers or neotenics. Slight variations in alate size and antennal morphology result from their origin in different larval instars. Whole-colony censuses revealed that the major part of the colony's work force is composed of pseudergates, i.e. late larvae that do not follow the most direct pathway to the alate. The pseudergates of Prohinotermes do not constitute a distinct worker caste irreversibly diverted from the alate developmental pathway. For this reason the caste system of Prorhinotermes is analogous to that of the Kalotermitidae and Termopsidae and much more primitive than those of the other Rhinotermitidae so far studied, Reticulitermes, Schedorhinotermes and Coptotermes.

Morphology, development and evolutionary significance of the working stages in the caste system of Prorhinotermes (Insecta, Isoptera)*

In the past five decades, major advancements in the understanding of subterranean termite biology have been made, partially thanks to the research that focused on Coptotermes pest species. In this chapter, a comprehensive overview of the Coptotermes colony life cycle is placed in the broader context of termite biology, to assemble the interconnected pieces of a complex sociobiological entity. As eusocial cockroaches, termite biology is deeply rooted in its ancestral hemimetabolous developmental constraints, and the life cycle of a termite colony reflects this aspect throughout its lifetime. Each individual termite develops in a socio-environmental context that influences its caste determination, its function within the colony and its potential longevity. A Coptotermes colony goes from foundation to death by passing through major steps of colony growth and maturation, while optimizing reproductive output and high colony fitness over time. This chapter provides a systemic approach to this Coptotermes biology, with first a focus on individual termite development, physiology, symbiosis, and behavior, to the colony-wide implications of individual differentiation over time, and finally, with important considerations for colony demographic alteration throughout the lifetime of a Coptotermes colony. 

A primer to termite biology:Coptotermescolony life cycle, development, and demographics

The hemimetabolous termites have a very different caste system from social Hymenoptera in which only true imagoes participate in all social tasks. In termites, the imagoes are restricted to reproduction. The termite solidiers have no equivalent in other social insects. They are unique both in their post-embryonic development and their exclusively defensive function. At maturity they keep their molting gland and therefore should be considered as stabilized, differentiated immatures. They appeared monophyletically, early in the evolution of termites.

Ontogenetic development and evolution of the worker caste in termites

Publisher Summary This chapter discusses that lower termites comprise several evolutionary lines and do not constitute a systematic unit. The species of the lower termites has reached different degrees of evolution, especially in their caste development. By comparative studies, it is possible to reconstitute the main steps of the evolution of the caste system in the Isoptera, especially the emergence of the worker caste. In spite of recent contrary assertions, the developmental pathway well evidenced in Kalotermes flavicollis is general for the Kalotermitidae and Termopsidae. From the normal developmental line, ending in the sexual alates, many deviations occurs, and gives rise to the soldiers, the neotenic reproductives and the pseudergates. This caste appears as an irreversible deviation from the normal developmental line, realized at a definite larval instar. The earlier it appears the more evolved the species. Several steps of this evolution are observed in the Rhinotermitidae. Polymorphism of Mastotermitidae—where a worker line seems separated at the first moult—remains unexplained.

Pathways of Caste Development in the Lower Termites

Les etudes biometrique et morphologique du couvain permettent de distinguer chezCoptotermes intermedius deux stades larvaires communs a la lignee des imagos et a celle des ouvriers. La lignee des soldats ne semble pas etre differenciee des le troisieme stade.

Études biométrique et morphologique du couvain deCoptotermes intermedius Silvestri (Isoptère Rhinotermitidae)

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of {limit} columns in the table. Remove at least 1 column to add or create another one.

J. Roy-Noël

Author Tools

Chat about Author

Papers

Études biométrique et morphologique du couvain deCoptotermes intermedius Silvestri (Isoptère Rhinotermitidae)