Many (most?) cetoniines do not go to flowers. In the New World the three primary cetoniine feedings strategies are 1) sapping (feeding on plant exudates, especially fermenting sap flows (see pic below) and on fruit (usually in later stages of “ripeness,; most species in this group feed on both sources), 2) feeding on/in flowers, and 3) carnivory (Cremstocheilini). In addition there are some that feed on roots as adults: When you see species with erect (sharp) teeth on the clypeal apex, suspect root feeding (e.g. as in the former “Stephanucha” species). Euphoria verticalis can often be found by pulling up sunflowers by their roots, the adults have there heads burried in a hole they’ve made in the tap root. The dynastine Oxygrylius ruginasus is usually doing the same thing on the same plant root; my record thus far for E. verticalis on a single sunflower root is 22 specimens.
About 20 adult Australian Schizorhinini (Cetoniinae) species have never been found on flowers or observed feeding. So far we haven't referred to it as non-feeding but as 'never found on flowers' (which also requires a different mate selection strategy than in most cetoniines). You will find that said on page 2, 2nd column, 2nd paragraph. Mouth parts may be functional, since those I've reared lapped up sugar water after hatching.
Moeseneder, C., Weir, T., Lemann, C., Hutchinson, P. (2019) 'Chapter 34 Cetoniinae', in Slipinksi, A., Lawrence, F. (eds.) Australian Beetles. Volume 2. Canberra: CSIRO Publishing. pp. 531-553. pl. 73-76. ISBN 9780643097308
From: Scarab Beetle Taxonomy Discussion List <[log in to unmask]> on behalf of Dirk Ahrens <[log in to unmask]>
Sent: Sunday, March 15, 2020 3:52 AM
To: [log in to unmask] <[log in to unmask]>
Subject: Non-feeding adults in Scarabaeoidea
in a work in preparation we would like to give in a few sentences a short review on non-feeding scarab adults.
Could you guys give us a help to make this thing more complete?
There are in literature some vague statements such as this of Ritcher (1958) and Scholtz (1990) about nonfeeding Rutelinae and Dynastinae, for which I could find so far no precise data on taxa and references. Maybe I have overlooked other references…
In order to avoid notification already known to us, I attached below the list I could make so far…
Thanks to all in advance who may help!
ps. Do we have this pattern (i.e., nonfeeding of adult specimens) also among dung beetle lineages (Aphodiinae/ Scarabaeinae)?
Non-feeding in Scarabaeoidea
· Diphyllostoma (Lucanidae; nonfunctional mandibles; maxillae with a small rounded galea; Nel & Scholtz 1990)
· Amphicoma, Lichnanthe (Glaphyridae; Ritcher 1958; Sabatinelli et al. 2020)
· Pleocoma (Pleocomidae; Ritcher 1958; nonfunctional mandibles; maxillae with a small rounded galea; Nel & Scholtz 1990
· Pachypus (Pachypodiini; Crovetti 1968)
· Ceramida (Tanyproctini; very simple and reduced mouthparts; Sanmartin & Martin-Piera 2000; some more candidates with reduced epipharynx: Alaia, Atanyproctus, and Otoclinius)
· Aclopus (Aclopinae; reduced galea, simple epipharynx; Nel & Scholtz 1990)
· Xenaclopus (Melolonthinae, s.l. (Ocampo & Vaz de Mello 2008): reduced galea, simple epipharynx; Nel & Scholtz 1990)
· Scapanoclypeus ("Tanyproctini" (see Eberle et al. 2018); epipharynx reduced, galea, lacinia, ligula absent; Nel & Scholtz 1990)
· Sebaris, Pseudachloa, Eucyclophylla (Melolonthinae, s.l.; galea oval with setae; group 4 and 5; Nel & Scholtz 1990)
· "There are species in each of the subfamilies Melolonthinae, Rutelinae, and Dynastinae which do not feed at all in the adult stage" (without specifications; Ritcher 1958, Scholtz 1990)