A new term for an important biological phenomenon: introducing 'secromorphosis' as categorically distinct from metamorphosis

Before reading this Post, please watch https://www.youtube.com/watch?v=3EVLJChVV48.

Everyone knows that

certain arthropods undergo metamorphosis (https://en.wikipedia.org/wiki/Metamorphosis and https://www.perplexity.ai/search/why-are-those-insects-possessi-nbMZwWoaShG3_0B0oBfGSg), and
metamorphosis is fundamental to the life-history strategy of insects in particular.

However, there is another process whereby the bodies of arthropods are radically modified. This deserves a term of its own: secromorphosis.

[As a necessary digression, please note a terminological quirk. The biological adjective derived from the noun 'metamorphosis' is 'metabolous', not 'metamorphic'. Likewise, those derived from holometamorphosis and hemimetamorphosis are respectively holometabolous and hemimetabolous. In accordance, the adjective derived from my new term - albeit unsatisfactory owing to some ambiguity with metabolism - would be secrobolous, not secromorphic.]

In metamorphosis,

the tissues of the body are reformulated/reconstituted to change the form of the soma (https://dictionary.cambridge.org/dictionary/english/soma), by pupation or ecdysis, or both, and
the important point is that no secretion (https://www.merriam-webster.com/dictionary/secretion) of structures is necessary.

By contrast, in secromorphosis, the transformation of the body - which can be extreme (https://lostcoastoutpost.com/nature/5938/ and https://australian.museum/learn/animals/insects/giant-female-scale-insects-and-bird-of-paradise-flies/ and https://www.ecoorganicgarden.com.au/problem-solver/how-to-control-lerps/ and https://www.dpi.nsw.gov.au/agriculture/horticulture/citrus/content/insects-diseases-disorders-and-biosecurity/insect-pest-factsheets/long-tailed-mealy-bug#:~:text=Description&text=Adults%20are%203%E2%80%934%20mm,a%202%E2%80%933%20week%20period. and https://www.projectnoah.org/spottings/135616016 and https://www.projectnoah.org/spottings/21883009 and https://upload.wikimedia.org/wikipedia/commons/a/af/Ceroplastes_cirripediformis.jpg and https://upload.wikimedia.org/wikipedia/commons/3/30/Red_lerps_austrochardia_acaciae.jpg) - is achieved by means of secretion.

https://www.treehugger.com/the-planthopper-nymphs-dazzling-style-of-protection-4868356

The body-parts secreted - '3-D printed', as it were, by glands - consist mainly of various organic compounds (https://www.perplexity.ai/search/what-is-the-overall-term-for-m-vzBxp5QiQsiuxJqs.GQVnQ), including both

those containing oxygen, and
those lacking oxygen, and best-described as hydrocarbons (https://en.wikipedia.org/wiki/Hydrocarbon).

These secreted structures, which can be substantial relative to body size, are non-living, even though they form part of a living body.

It is true that important components - particularly the exoskeleton and wing-membranes - of the body in metabolous arthropods consist of dead tissue. However, there is a categorical distinction between once-living (i.e. metabolising, containing DNA, and undergoing cell-division), now-dead materials on one hand, and materials that have never been alive on the other.

The relevant body-parts of secromorphic insects, particularly the waxy filaments, shields, and lattices secreted by sap-sucking sternorrhynchan hemipterans (https://en.wikipedia.org/wiki/Sternorrhyncha), fall into the latter category.

Everyone knows that the bodies of arthropods contain non-living components, particularly exoskeletons made of chitin (in some cases reinforced by calcium carbonate).

However, all chitinous body-parts are derived from cell-walls. In other words, they originate as living tissues that have then died and become indurated.

The crucial distinction is that the components produced in secromorphosis are not aptly described as dead. This is because - like secretions as a category - they were not metabolically active in the first place.

Within Hemiptera, the trend is for an inverse correlation between chitinousness and waxiness. Heteroptera rely on chitin, whereas Sternorrhyncha tend to have minimal exoskeletons, relying instead on wax. Achenorrhyncha are intermediate in this respect.

As far as I know,

all secrobolous insects are also hemimetabolous, i.e. they show hemimetamorphosis in the form of an ontogenetic series of nymphs culminating in an adult, and
most or all secrobolous insects fall within Hemiptera (https://en.wikipedia.org/wiki/Hemiptera).

It follows that most or all secrobolous insects are sap-suckers, foraging mainly on the fluid contents of phloem (https://en.wikipedia.org/wiki/Phloem).

This leads to a strange realisation: that hemipterans manifest two aspects of a rapid throughput of carbon and hydrogen, and to some extent oxygen.

Sap-sucking hemipterans take in much superfluous sugar as they filter dilute fluids for their content of nitrogen and mineral nutrients. As part of this process, they exude the energy-content of most of this sugar, whether as

unmodified sugar (honeydew, which qualifies as excretion as much as secretion, https://en.wikipedia.org/wiki/Honeydew_(secretion)), or
polymerised carbohydrate (lerp, which consists of mainly starchy, somewhat durable, polysaccharide secretions, https://en.wikipedia.org/wiki/Lerp_(biology)), or
organic wax, which probably requires more metabolic energy to synthesise enzymatically than does polymerisation (https://www.perplexity.ai/search/in-the-cells-of-some-organisms-_vtnUGdtQj6gekN8RWLmBg), or
hydrocarbon wax, which is presumably the most costly secretion in this context, in terms of metabolism and autotoxicity.

There is a kind of congruence in the fact that sap-sucking hemipterans

take in large quantities of energy superfluous to metabolism, and
subsequently exude (3-D print, https://en.wikipedia.org/wiki/3D_printing) the energy-containing substances, in modified form, for various purposes.

In the case of most secrobolous hemipterans (belonging to a bewilderingly large number of families in two suborders and many superfamilies):
sugar in, wax out.

And wax can be so much more durable/imperishable than sugars - indeed, almost as durable as chitin in the case of small insects - that it can effectively constitute a large proportion of the body (albeit extraneous to the tissues, both living and dead).

In the past, most insects have been categorised as either holometabolous or hemimetabolous. With the realisation that many sternorrhynchan and some auchenorrhynchan hemipterans are secrobolous, how should woolly aphids, lerp psyllids, wax scalebugs, etc., be best categorised?

Relevant to this question is the observation that the waxy secretions are best-developed in nymphs in some clades of hemipterans, vs in adults in other clades. In some families, even the eggs are invested in waxy filaments (https://www.perplexity.ai/search/in-which-sternorrhynchan-and-a-SD3Y5dGdRjOM_qDIWNoKZw).

In extreme cases, an adult the size of a small fly (https://upload.wikimedia.org/wikipedia/commons/8/89/Bird_of_Paradise_Fly.jpg) may possess a waxy 'tail', consisting of filaments up to 7.5 cm long (https://www.inaturalist.org/taxa/706751-Callipappus-australis and https://www.perplexity.ai/search/which-sternorrhynchan-hemipter-b8qjNcwDQvOh4qos8rQxSQ).

Given that the secretions correspond incongruently to growth-stages, across the various clades of hemipterans, I would argue that the categorisation of certain taxa as secrobolous is more relevant/informative than their categorisation as hemimetabolous.

Here is a question corollary to this topic:
Does any insect secrete chitin, which is a polysaccharide, viz. a polymer of sugar (https://www.perplexity.ai/search/is-any-arthropod-known-to-secr-xA81XDKuT4ykAEVrVpQxaA)?

SUPPLEMENTARY DEFINITIONS AND CLARIFICATIONS

https://www.perplexity.ai/search/some-waxes-qualify-as-hydrocar-mDycdLR.SEau1cXA_07e4A

https://www.perplexity.ai/search/does-the-term-imago-apply-to-h-2UJbwMNjTySOK7itutyHFg

https://en.wikipedia.org/wiki/Imago

https://en.wikipedia.org/wiki/Instar

https://www.perplexity.ai/search/consider-the-wings-of-a-butter-VMmn0357Ts6wZVsfsOwK6g

https://www.perplexity.ai/search/keratin-is-a-protein-is-chitin-GdtZaMicQTiuWVYVQ1Q1NA

https://www.perplexity.ai/search/many-hemiptera-exude-waxy-stru-miLLSSHESEyi0fyKlhdskQ

https://www.perplexity.ai/search/do-any-crustaceans-undergo-met-G2jx7A7NSd2f4DavQcp6RA

https://www.perplexity.ai/search/is-starch-a-polysaccharide-Tw0HHpHHTFiADMI7PBn74A

https://www.perplexity.ai/search/do-both-larvae-and-nymphs-occu-LY4JgZMATj6vjnJqKaXWag

https://www.perplexity.ai/search/in-hemiptera-is-honeydew-produ-9mwXoi_VT8W9FuJaSF0H6w