Rigoutorum a new genus for Diaphonia bacchusi Rigout and Allard (Coleoptera: Scarabaeidae: Cetoniinae: Schizorhinini), with description of a second species from Western Australia and notes on habitats and behaviours Author Hutchinson, Paul M. Department of Primary Industries and Regional Development, Quarantine Western Australia, Locked Bag 69, Welshpool DC, Western Australia 6986, Australia. Author Moeseneder, Christian H. 0000-0002-6718-1913 CSIRO Oceans and Atmosphere, Queensland Biosciences Precinct, 306 Carmody Road, St Lucia, Queensland 4067, Australia. chris. moeseneder @ csiro. au; https: // orcid. org / 0000 - 0002 - 6718 - 1913 & Australian Museum, 1 William Street, Sydney, New South Wales 2010, Australia. chris.moeseneder@csiro.au Author Mitchell, Andrew Australian Museum, 1 William Street, Sydney, New South Wales 2010, Australia. text Zootaxa 2022 2022-06-07 5150 2 239 259 journal article 68520 10.11646/zootaxa.5150.2.4 7855152c-c1c5-4aa4-a13b-1d93eab53d14 1175-5326 6621254 925781D5-F885-4892-ABBA-822E85E23CF4 Genus Rigoutorum Hutchinson & Moeseneder , new genus ( Figs 4–6 , 8–10 ) http://zoobank.org/NomenclaturalActs/0b3827fe-945e-4a1d-aafb-38e61a5ff30e Type species: Diaphonia bacchusi Rigout & Allard, 1997: 26 ; here designated. Included species: Diaphonia bacchusi Rigout & Allard, 1997 ; Rigoutorum jakli new species Description. Length 12.5–18.9 mm . Form elongate ovate. Colour black (females) or brown with yellow elytra and maculation (males). Head . Clypeus quadrate, lateral margins divergent, parallel in apical half, widest apically; clypeolateral ridges present, parallel, anterior margin linear sinuate medially; margins abruptly inclined to high elevations; disc coarsely punctate. Frons coarsely punctate. Antennal club not enlarged in male, same length as antennomeres 2–7. Thorax . Pronotum transverse trapezoidal; basomedian margin weakly concave-linear; lateral margins with broad median angles; disc punctate. Scutellum base broad, elongate, coarsely punctate. Elytron with posthumeral arch linear (in dorsal view), slightly exposing metacoxa, then slightly convergent to broad arcuate apex; mesepimeron slightly exposed; humeral and apical umbones indistinctly raised; sutural costa distinct, each elytron with one complete, indistinct, low costa; disc punctate in irregular lines. Mesometasternal process undeveloped, present as low parallel process, declivous at anterior margin of mesocoxae. Legs . Protibiae unidentate, denticle elongate; protarsomeres elongate and simple. Mesotibiae broadest in basal half, not bidentate or weakly bidentate, concave in apical half. Mesotarsomeres elongate and simple. Metafemora elongate, anterior margin arcuate. Metatibiae elongate, narrow, parallel in apical half, angulate to weakly denticulate at mid-length; spurs elongate parallel, broader in females. Metatarsomeres elongate and simple. Abdomen . Sternites distinctly concave in males, convex in females. Metasternum sparsely punctate medially, rugulose laterally. Pygidium concentrically rugulose. Genitalia ( Fig. 10 ). Phallobase to paramere length ratio 2:1, phallobase widest at apex with narrow, deep medial longitudinal groove on dorsal surface, parameres narrowing from base; sinuate concave widening near apex; dorsal cleft basally acute, narrowly ovate in basal half, then attenuate to apex. Differential diagnosis. The following combination of characters distinguishes Rigoutorum from other genera of Schizorhinini. Size 12.5–18.9 mm ; clypeus quadrate with clypeolateral margins abruptly and highly elevated; anterior margin linear; antennal club not enlarged, same length as antennomeres 2–7; head and pronotum punctatesetose; male protibiae unidentate; mesometasternal process undeveloped. Table 2 provides distinguishing characters among Rigoutorum , Diaphonia and Aurum Hutchinson & Moeseneder, 2019 . TABLE 2. Comparison of characters among the genera Rigoutorum , Diaphonia and Aurum .

Character	Rigoutorum	Diaphonia	Aurum males
(females unknown)
Male antennal club	Not enlarged, shorter than	Enlarged, same length or	Not enlarged, shorter than anten-
length	or equal to antennomeres	longer than antennomeres	nomeres 2–7.
2–7, same length as that of	1–7, longer than that of
female.	female.
Clypeal shape	Quadrate (length:width	Elongate, widest at	Quadrate (length:width equal);
equal); apical margin	pre-apex; apical margin	apical margin sinuate; anterior
linear-sinuate; anterior and	sinuate-arcuate bilobate;	and lateral margins (clypeolateral
lateral margins (clypeolat-	anterior and lateral mar-	ridges) gradually raised and low.
eral ridges) abruptly and	gins (clypeolateral ridges)
highly elevated.	not abruptly elevated.
Pronotal shape	Attenuate linear in basal	Trapezoidal, widest at	Cap-shaped, narrow and parallel in
half, angulate medially,	base.	basal third.
then attenuate-linear to
apex, narrowly exposing
mesepimeron.
Elytra, subhumeral arch	Sinuate-linear, not expos-	Shallow, distinctly arcuate,	Distinctly arcuate, exposing ster-
in dorsal view	ing sternites.	not exposing sternites.	nites.

Mesometasternal process	Undeveloped; parallel-sid-	Fungiform; apex moder-	Cap-shaped; parallel sided; short,
ed; apex arcuate; declivous	ately to greatly expanded	not surpassing mesocoxae.
between mesocoxae.	laterally; surpassing
mesocoxae.
Male protibial denticles	Unidentate	Tridentate	Tridentate
Metatarsomere bristles	Absent (setae only)	Present (except in D.	Absent (setae only)
dispar )
Phallobase structures	Unadorned	Unadorned	Medially sclerotised

Specimens examined: Rigoutorum bacchusi ; Rigoutorum jakli new species ; Aurum leonorensis ; Diaphonia dispar ; Diaphonia xanthopyga ; Diaphonia melanopyga Lea, 1914 ; Diaphonia luteola ; Diaphonia vicina ; Diaphonia notabilis White, 1846 ; Diaphonia antoinei Allard, 1995 ; Diaphonia lateralis Blackburn, 1894 . Remarks. In Moeseneder et al. (2019) , Rigoutorum keys out at couplet 42 “ Diaphonia bacchusi … Diaphonia Newman (part)”. In Krikken (2018) , Rigoutorum keys out at couplet 21 “ Diaphonia and Chondropyga ”. Hutchinson & Moeseneder (2019) give differential characters of Aphanesthes , Aurum , Chondropyga Newman, 1840 , Diaphonia , Diaphonia bacchusi and Diaphonia kerleyi Rigout & Allard, 1997 . This study is our first step towards addressing the complex relationships among Diaphonia , Aphanesthes , Hemichnoodes , Pseudoclithria and Metallesthes . Mitchell et al. (2020) noted that “While the sampled species in this group are well defined, extensive further work is required to understand the relationships between these species and the status of the five current genera.” Natural history. Behaviourally, Rigoutorum belongs in the non-flower-visiting group of Australian Schizorhinina genera where males are usually seen in flight and females are sedentary and rarely observed. This is also the case in Aurum , Diaphonia , Pseudoclithria , Grandaustralis Hutchinson & Moeseneder, 2013 , Navigator Moeseneder & Hutchinson, 2016, and Tapinoschema Thomson, 1880 . The flower-visiting group of genera are mostly found congregating on flowers with males and females in similar numbers and both sexes having similar-sized antennae ( e.g. Metallesthes , Hemichnoodes , Aphanesthes ) ( Hutchinson & Moeseneder 2013 , 2019; Moeseneder et al. 2014 , 2019; Moeseneder & Hutchinson 2016 ). Aurum and Rigoutorum new genus constitute a subset of the former group in which male antennal clubs are not enlarged. Etymology. The genus is named in honour of the Rigout family. Jacques Rigout contributed to the taxonomy of Batocerini ( Coleoptera : Cerambycidae ), Cetoniini and Schizorhinini (Cetoniinae), describing numerous new species. The Rigout family travelled to New Guinea researching Schizorhinini. Lydia Rigout operated Hillside Books.