Aulacocyclinae Kaup, 1868

Fonseca, Claudio Ruy Vasconcelos Da, Barbosa, Márcio Luís Leitão & Fernandez, Maria Fernanda Souza, 2011, A hypothetical evolutionary history of passalid beetles narrated by the comparative anatomy of the hindgut (Coleoptera: Passalidae), Zootaxa 3012, pp. 1-20 : 5-6

Subfamily Aulacocyclinae Kaup, 1868

( Fig. 1 )

The genera Aulacocyclus Kaup ( Fig. 1 A), Comacupes Kaup ( Fig. 1 B), Taeniocerus Kaup ( Fig. 1 C), Cylindrocaulus Fairmaire ( Fig. 1 D) and Ceracupes Kaup ( Fig. 1 E) are included in this subfamily. The ileum in these genera is similar to Scarabaeidae ( Umeya 1960; López-Guerrero 2002), where the diverticula are assembled around the proximal edge and vary in shape and number. There are about six diverticula in Comacupes and none in Cylindrocaulus , but the average is three to four for the subfamily. As to segmentation, there is variation from broad ( Comacupes ) to close clustering, which makes the ileum look bellow-shaped ( Cylindrocaulus ).

Branch Solenocyclinae+ Figs 2–8

This branch embodies all genera that are part of Passalinae in Reyes-Castillo’s (1970) classification. The features of the ileum confirm this observation, as it is obvious that Solenocyclinae+ is the sister group of Aulacocyclinae . Concerning the ileum architecture, Solenocyclinae+ show transformations that start to become noticeable on the African genera Stephanocephalus Kaup ( Fig. 2 C), Didimus Kaup ( Fig. 2 D), Pentalobus Kaup ( Fig. 2 E), Semicyclus Kaup ( Fig. 2 F) and Flaminius Kuwert ( Fig. 3 E), possessing a collection of protuberances in the distal half. In Solenocyclus Kaup ( Fig. 3 A), Vitellinus Kuwert ( Fig. 3 B), Ciceronius Kaup ( Fig. 3 C) and Erionomus Kaup ( Fig. 3 D), such protuberances extend their range to cover the whole surface of the ileum. The number and size of the protuberances are not constant, as sometimes they can be dense in Leptaulax Kaup ( Fig. 2 B), giving a very striking differentiation to the ileum. In addition to the protuberances, the long diverticula, which arise from the proximal region in Aulacocyclinae , undergo shortening in the Solenocyclinae+, and in some instances turning into just one diverticulum. Protuberance clustering increases in taxa from Indo-Australian Pleurarius Kaup ( Fig. 7 A) to Neotro- The Neotropical taxa are included in two tribes: Passalini and Proculini ( Boucher 2006) . The ileum in most genera of Proculini (exposed clypeus); Odontotaenius Kuwert ( Fig. 4 A), Spurius Kaup ( Fig. 4 B), Popilius Kaup ( Fig. 4 C), Pseudacanthus Kaup ( Fig. 4 D), Vindex Kaup ( Fig. 4 E), Petrejoides Kuwert ( Fig. 4 F), Heliscus Zang ( Fig. 4 G), Chondrocephalus Kuwert ( Fig. 4 H), Verres Kaup ( Fig. 5 A), Veturius Kaup ( Fig. 5 B) and Proculejus Kaup ( Fig. 5 C); has the long diverticulum facing down. The long diverticulum faces up for Proculus Kaup ( Fig. 5 G), in which the ileum is formed by large diverticula on the proximal region that becomes smaller towards the distal apex. On the other hand, the large, closely clustered protuberances distinguish Proculus from all other Proculini . In the Passalini (hidden clypeus); Ptichopus Kaup ( Fig. 6 A), Passalus ( Fig. 6 B), Spasalus Kaup ( Fig. 6 C), Paxillus MacLeay ( Fig. 6 D) and Passipassalus Fonseca & Reyes-Castillo ( Fig. 6 E); the ileum becomes flattened and the protuberances increase from four to six rows, becoming noticeably denser in Macrolininae.

Figures

FIGURE 1. Aulacocyclinae hindgut. A— Aulacocyclus edentulus (MacLeay), Australia; B— Comacupes cylindraceus (Perty), Philippines; C— Taeniocerus bicanthatus (Percheron), Borneo; D— Cylindrocaulus bucerus Fairmaire, Japan; E— Ceracupes fronticornis (Westwood), Taiwan.

FIGURE 2. Solenocyclinae hindgut. A— Trichostigmus thoreyi (Kaup), Philippines; B— Leptaulax dentatus (Fabricius), India; C— Stephanocephalus hostilis (Percheron), Madagascar; D— Didimus aberrans (Kuwert), Democratic Republic of the Congo; E— Pentalobus barbatus (Fabricius), Ivory Coast; F— Semicyclus grayi Kaup, Madagascar.

FIGURE 3. Solenocyclinae hindgut. A— Solenocyclus exaratus Klug, Madagascar; B— Vitellinus approximatus (Klug), Madagascar; C— Ciceronius morbillosus (Klug), Madagascar; D— Erionomus planiceps (Eschscholtz), Democratic Republic of the Congo; E— Flaminius nonfriedi Kuwert, Madagascar.

FIGURE 4. Proculinae hindgut. A— Odontotaenius striatopunctatus (Percheron), Mexico; B— Spurius bicornis (Truqui), Costa Rica; C— Popilius marginatus (Percheron), Brazil; D— Pseudacanthus mexicanus (Truqui), Mexico; E— Vindex agnoscendus (Percheron), Mexico; F— Petrejoides tenuis Kuwert, Costa Rica; G— Heliscus tropicus (Percheron), Mexico; H— Chondrocephalus granulifrons (Bates), Mexico.

FIGURE 5. Proculinae hindgut. A— Verres corticicola (Truqui), Mexico; B— Veturius heydeni (Kaup), Venezuela; C— Proculejus truquii Kaup, Mexico; D— Ogyges laevissimus (Kaup), Guatemala; E— Undulifer incisus (Truqui), Mexico; F— Oileus rimator (Truqui), Mexico; G— Proculus goryi (Melly), Guatemala; H— Xylopassaloides pterocavis Reyes-Castillo, Fonseca & Castillo, Mexico.

FIGURE 6. Passalinae hindgut. A— Ptichopus angulatus (Percheron), Costa Rica; B— Passalus interruptus (Linnaeus), Brazil; C— Spasalus crenatus (MacLeay), Puerto Rico; D— Paxillus leachi MacLeay, Brazil; E— Passipassalus buhrnheimi Fonseca & Reyes-Castillo, Brazil (Fig. E from Fonseca & Reyes – Castillo 1993).

FIGURE 7. Macrolininae hindgut. A— Pleurarius pilipes Kaup, India; B— Ophrygonius inaequalis (Burmeister), India; C— Episphenus moorei Kaup, India; D— Aceraius grandis (Burmeister), Taiwan; E— Macrolinus latipennis (Percheron), Java; F— Pseudepisphenus perplexus Gravely, New Guinea; G— Protomocoelus australis (Boisduval), Solomon Islands; H— Labienus ptox (Kaup), New Guinea; I— Analaches puberilis Kuwert, New Guinea.

FIGURE 8. Macrolininae hindgut. A— Mastochilus polyphyllus (MacLeay), Australia; B— Pharochilus dilatatus (Dalman), Australia; C— Cetejus virginalis (Kaup), New Guinea; D— Gonatas naviculator (Percheron), New Guinea; E— Plesthenus quadricornis (Kaup), Sulawesi; F— Pelopides gravidus (Kuwert), Sumatra.