Anamorphidae

Arriaga-Varela, Emmanuel, Leschen, Richard A. B. & TomaszeWska, Wioletta, 2023, The debris-cloaking larva of Catapotia laevissima and the origin of defensive strategies in Anamorphidae and other Coccinelloidea (Coleoptera), Organisms Diversity & Evolution (New York, N. Y.) 23 (4), pp. 901-915 : 910

Debris-cloaking in Anamorphidae

The diversity of immature stages in Anamorphidae has been poorly documented. Of the 35 genera known in the family, larvae have been described for only five genera ( Shockley & Tomaszewska, 2007) and observations about behaviour and functional morphology are scarcer. Larval behaviour of C. laevissima was not observed, and though we now can place the unidentified larvae observed by Leschen and Carlton (1993) into Catapotia , this information assists little in developing a complete behavioural repertoire of loading and manipulation of debris onto the dorsal surface of the body, or whether behavioural traits are common throughout Anamorphidae . We can, however, confirm that the materials used are variable (exuviae, detritus, plant, and fungal tissue) and describe morphology associated with debris-cloaking.

Larval Catapotia and Bystus share a similar body form. The setose lateral thoracic lobes may function similarly with setae for capturing debris and centring it on the body. The dorsal setae, however, differ. Bystus decorator Leschen & Carlton, 1993 , and Catapotia spp. share the spoon-like apical structure of the setae, but a barbed shaft occurs only in Bystus . Though Idiophyes niponensis retains exuviae and debris like Bystus and Catapotia , the setal structure was not described by Hayashi (1984). Contrary to lacewings where nude, non-camouflaged larvae lack textured setae ( Tauber et al., 2014), having barbed setae is not required for debris capture or retainment in anamorphids. It is worth noticing that the larvae of Symbiotes , an anamorphid genus in which debris-cloaking has not been observed, lack the lateral thoracic lobes ( Shockley & Tomaszewska, 2007). This reinforces the idea that the presence of these lobes in Anamorphidae is associated with debris manipulation.

How anamorphid larvae choose debris, manipulate the material onto their bodies, retain, and use it in defence remains mysterious. While the function of debris-cloaking in chrysopids has been studied experimentally ( Eisner et al., 1978; Hayashi & Nomura, 2011; Nakahira & Arakawa, 2006), no studies exist for anamorphids, and the actual defensive use of a covering with debris and exuvial skins has yet been explored. It is also not confirmed that debris-cloaking and exuvial retention in Anamorphidae is used for camouflage or crypsis (sensu Endler, 1981) or as a type of extrinsic autotomy ( Yoshida & Leschen, 2020), where potential predators are left with a mouthful of debris or exuvia. Additionally, the actual interactions with predators and parasiotoids have not been observed or explored under natural conditions or in the lab. This can be done experimentally, by exposing debris covered and nude larvae to predators and evaluating survival or aggression rates between these classes.