A Synopsis of the New World Genera of Phileurini (Coleoptera: Scarabaeidae: Dynastinae), with English and Spanish Keys to the Genera

The 22 genera of New World Phileurini are briefly reviewed and characterized, and English and Spanish keys to all the genera are provided for the first time, thus facilitating generic identifications. Chili-phileurus Endrödi (a junior synonym of the Asian genus Eophileurus Arrow), Moraguesia Dechambre (transferred to Oxyligyrus Arrow in the tribe Pentodontini)


INTRODUCTION
Species in the tribe Phileurini are found in nearly all regions of the world, although most species occur in the tropics.The world fauna is comprised of 35 genera (Endrödi 1985) with 300 currently recognized species.In the New World, there are now 22 genera and 189 valid species.Endrödi (1977Endrödi ( , 1978Endrödi ( , 1985) ) provided the most recent, comprehensive review of the entire tribe, but new genera and 114 new species (37 % of all species currently known) have been described in the past 38 years.
Adult phileurines are recognized by their generally flattened body; large mentum that covers the bases of the labial palpi; a clypeal apex either acuminate or rounded; frons with one or two tubercles or horns; pronotum often with a longitudinal, median furrow and subapical tubercle; elytra usually flattened and either smooth or striate; protibia with three or four teeth; and apex of metatibia truncate or armed with one to three teeth (Endrödi 1977(Endrödi , 1978)).In some species, the concavity of the vertex on the head differs between the sexes, with the male having a deeply hollowed pit, while the female does not.
Adult phileurines are nocturnal, and many species are known by only a few specimens.Their rarity may result from genuinely small and/or dispersed populations, inadequate methods for attracting or collecting them, and our lack of knowledge of where to look for them.Adults of a few species have been attracted to lights, but in our experience phileurines are not as readily attracted to lights as are many other dynastines.This may be because adults live in and on rotting tree trunks and stumps where they do not usually "see" the occasional light trap.Some species are inquilines with ants or termites (Vanin et al. 1983, Ratcliffe andSkelley 2011), while others live in decaying wood in a fashion similar to that of passalids, although without subsociality.
The larval stages, life history, and larval development are poorly known.There is evidence that adults of some species may be predaceous on other insects (McCleve 2007, Ratcliffe et al. 2020).A few larvae have been collected from rotting wood or termite or ant nests.There is a genuine need for laboratory rearing, so that larvae and their subsequent descriptions can be associated with adults.This opportunity will fall largely to resident entomologists in the countries in which these species occur, since visiting researchers on short collecting trips cannot hope to efficiently accomplish this task.
The genus Amblyodus (Fig. 1c) contains two species, with A. taurus Westwood, 1878 occurring in Costa Rica, Panama, and Nicaragua (Bates 1888, Ratcliffe 2003a) and A. castroi Grossi and Grossi, 2011 found in Peru and Brazil (Grossi and Grossi 2011).Endrödi (1977)  Other than being attracted to lights (although perhaps not strongly so), nothing is known of the biology of the species in this rarely collected genus.Endrödi (1977Endrödi ( , 1985) ) reviewed the genus.
The species of Amblyoproctus are all small (none exceeding 17 mm); possess two or three small spinules on the apical angle of the metatibia; have narrow mandibles lacking teeth; have a median, longitudinal furrow on the pronotum; and the apex of the prosternal process projects angularly backwards.Nothing is known of the natural history of Amblyoproctus species other than they live under the bark of rotting logs, and adults are occasionally attracted to lights.Endrödi (1977Endrödi ( , 1985) ) provided the most recent review of the genus, although new species have been described since.
Anisophileurus Prell 1912: 182 (described as a subgenus of Amblyphileurus; synonym).Archophileurus (Fig. 1e) currently contains 33 species (Endrödi 1977, 1985, Morón 1990, Lamant-V 1995 Endrödi, 1969 with Archophileurus fodiens (Kolbe, 1910).The species of Archophileurus are characterized by the presence of two tubercles or short horns on the head; apex of the metatibia truncate and with numerous small spinules; and a distinctive fringe of reddish-brown setae arising from beneath the lateral pronotal margins.Many species are rarely collected, often as singletons, and a female not associated with a male at the time of collection is virtually impossible to identify.Specimens in older collections are frequently misidentified, especially if the essential parameres have not been examined to determine their form, and so the distributional data based on undissected museum specimens is questionable.
The immature stages and life history are unknown for all species.Endrödi (1977Endrödi ( , 1985) ) provided the most recent synopses of Archophileurus, but seven species have been described since his latest synopsis.Di Iorio et al. (2017) reviewed in detail the species from Argentina.

Argentophileurus Penco and Zubarán, 2013
Argentophileurus Penco and Zubarán 2013: 23.Penco and Zubarán (2013) established the genus Argentophileurus (Fig. 2a) to accommodate a single new species, A. litoralensis Penco and Zubarán, 2003, characterized by simply curved mandibles; a metatibial apex with three blunt teeth; unique form of the parameres; and the first antennomere bulbous at its apex and subequal in size to the entire club that is almost twice as long as antennomeres 2-7.This species occurs in Argentina.Nothing is known of the life history of A. litoralensis except that adults come to lights (Mario Ibarra Polesel, personal communication 2022).
The monobasic genus Caymania (Fig. 2b) is known only from Little Cayman Island in the West Indies.Its species, C. nitidissima Ratcliffe and Cave, 2010, is characterized by small size (9.5-11.5 mm); strongly shiny and minutely punctate dorsal surface; dark reddish brown to almost black color; body slightly flattened dorso-ventrally; head lacking tubercles; small eyes (interocular width equals 9.0 transverse eye diameters); pronotum lacking a median furrow; elytra lacking striae; tridentate protibiae; and symmetrical parameres.The specimens of the type series were found beneath a rock.Nothing is known of the species' life history.
The rare Ceratophileurus lemoulti Ohaus, 1911 (Fig. 2c) is found in French Guiana and Suriname (Gillett et al. 2010).It is distinctive because of the long, recurved horn arising from the frons in both sexes.Well-developed specimens have a short, laterally compressed, truncate tubercle on each side of the pronotum.The few adult specimens known were all taken at lights, and the life history and immature stages remain unknown (Gillett et al. 2020).

Cnemidophileurus Kolbe, 1910
Cnemidophileurus Kolbe 1910: 335.Kolbe, 1910 (Fig. 2d) occurs in Amazonian Brazil and is the only species in the genus.It is morphologically unique in having a broadly rounded clypeal apex; a broad mentum; frons with two tubercles; pronotum with small, dense punctures and simply convex with a broad, shallow, longitudinal furrow; tridentate protibiae; metatibial apex with two large teeth; and form of the parameres.Dupuis and Perrin (2020) reported that this species is found in termite nests in French Guiana, but otherwise little is known of its life history.
The genus Goniophileurus (Fig. 3a) is distinguished by tridentate mandibles; tridentate protibia; pronotum with a narrow, longitudinal furrow; and metatibiae at the apex with three small teeth (one small tooth between two larger teeth).
Goniophileurus was reviewed by Endrödi (1977Endrödi ( , 1985) ) who recognized a single species, G. femoratus (Burmeister, 1847).Dupuis and Mantilleri (2013) transferred G. explanatus (Burmeister, 1847) from Metaphileurus Kolbe and synonymized it with G. femoratus.Goniophileurus is known from South America east of the Andes (Colombia, Ecuador, Venezuela, French Guiana, Bolivia, and Brazil), and it also extends into Central America (Panama, Costa Rica, Honduras, El Salvador, and Mexico) (Endrödi 1977, Ratcliffe 2003a, Ratcliffe and Cave 2006, Ratcliffe et al. 2013).Nothing is known of the natural history of the species in this genus other than some specimens were collected at lights.These are small, rarely collected scarabs.The immature stages are unknown.
Haplophileurus (Fig. 3b) currently contains three species, all from Andean South America.Haplophileurus species are very similar to Archophileurus species but have only one tubercle on the head.The immature stages and life history are unknown for all species, and the female is known for only H. caudipenis Dupuis, 2011. Dupuis (2011) provided the most recent synopsis of Haplophileurus species.

Phileucourtus Dechambre 2008b: 156 (New Synonym).
Hemiphileurus (Fig. 3c) is a large genus with 60 species.Endrödi (1977Endrödi ( , 1978Endrödi ( , 1985) ) was the last to comprehensively review the genus, although many new species have been described since (Howden 1978, Chalumeau 1981, 1988, Ratcliffe 1988, 2001, 2003a-b, 2014, Ratcliffe and Ivie 1998, Dechambre 2000, Dupuis and Dechambre 2000, Dupuis 1996, 2004a, Ratcliffe and Cave 2006, 2015, Neita-M and Ratcliffe 2010, Ratcliffe et al. 2023).There are now twelve species in the West Indies, 30 species in South America (some shared with Central America), 21 species in Mesoamerica, and one species in the USA.The genus Hemiphileurus continues to grow in number of species as new localities are explored and unidentified specimens already residing in research collections are studied.Compare, for example, Endrödi's (1985) listing of 24 known species with, just 38 years later, the 60 species now recognized.Many species are rarely collected, often as single-tons, and a female not associated with a male at the time of collection is almost impossible to identify.Specimens in older collections are frequently misidentified, especially if the essential parameres have not been examined to determine their form, and so the distributional data based on undissected museum specimens is suspect.
The genus is characterized by having acute, simply curved mandibles; clypeus triangularly acuminate and reflexed; frons with two tubercles (usually) or horns (occasionally) arising far from the lateral margin of the head (less distinct when horns are large with a larger basal footprint); pronotum with a longitudinal furrow but lacking an anterior fovea or strong declivity; apex of metatibia with a single, large tooth or spine on the upper angle and usually with several minute serrations and short spinules below the large tooth; and apex of the first metatarsomere extended into a long, acute spine.Most of the species are moderate in size at 16-24 mm in length.Because most species are so similar externally, great reliance must be placed on the form of the parameres for accurate identifications.Accordingly, most females can only be reliably identified when collected with males.
Our knowledge of the natural history and habits of these beetles remains scant as a result of the secretive habits of most of the adults and larvae.Adults are attracted to lights at night, and this is where virtually all specimens in collections were taken.Until our search pattern for collecting goes beyond light traps (such as employing extensive excavation of rotting logs), specimens of most Hemiphileurus species will remain uncommon in collections.
The larval stage for only three species, H. illatus (LeConte, 1854) (USA and Mexico), H. dispar Kolbe, 1910 (Hispaniola), and H. elbitae Neita-Moreno and Ratcliffe, 2010 (Colombia), are described (Ritcher 1966, Ocampo and Morón 2004, Neita-M and Ratcliffe 2010, respectively).Larvae for the remaining species remain unknown or undescribed.Larvae presumably live in decaying wood where they feed on the wood or associated fungi.Obtaining larval life history information will probably require on-site research and lengthy periods of laboratory rearing.Dechambre (2008b) briefly described Phileucourtus bicornutus as a new genus and species from Peru.Our examination of conspecific material from Peru indicates that the characters defining Phileucourtus are, in all respects, the same as those for Hemiphileurus except for the swollen protarsomeres of P. bicornutus.We do not believe that the enlarged protarsi are sufficient evidence for establishing a new genus and so reduce Phileucourtus to synonymy with Hemiphileurus.The presence or absence of an enlarged protarsus also occurs between species in other dynastine genera: Euetheola humilis (Burmeister, 1847) (enlarged) and Euetheola bidentata (Burmeister, 1847) (simple); Ligyrus peruvianus (Endrödi, 1970) (enlarged) and Ligyrus burmeisteri Steinheil, 1872 (simple).The body character states and especially the form of the parameres of P. bicornutus are identical with those of H. howdeni Endrödi, 1978, also from Peru, except for the swollen protarsi of P. bicornutus.
Homophileurus (Fig. 3d) is a relatively small genus consisting of ten species.Five species are found exclusively in South America, one is indigenous to Cuba and another to Central America, and three occur from Mexico to Brazil, with one of these also present in the West Indies (Endrödi 1978, 1985, Ratcliffe and Cave 2006, Dupuis 2012b, Ratcliffe et al. 2013).
Species in the genus are distinguished by the tubercles of the frons placed near the lateral margins of the head; quadridentate protibiae; and apex of the metatibia with three large teeth.Some of the larger species in the genus Phileurus are similar in overall appearance, including some with quadridentate protibiae, but none have three large teeth on the apex of the metatibia.The genus was comprehensively reviewed by Endrödi (1978Endrödi ( , 1985)).
Only the larva and pupa of H. luederwaldti (Ohaus, 1910) and the larva of H. integer (Burmeister, 1847), both South American species, are described (Costa et al. 1988, Ratcliffe andSkelley 2011, respectively).Little is known of the biology of any of the species.The larvae of some species probably live in rotting wood, while others are known to live in the nests of termites (Vanin et al. 1983, Costa et al. 1988, Neita and Ratcliffe 2011, Ratcliffe and Skelley 2011).
Adults are attracted to lights at night.
Metaphileurus (Fig. 4a) is comprised of two species that occur in South America.Dupuis (2014) removed a former third species, M. explanatus (Burmeister, 1847), to Goniophileurus.Species are characterized by bi-or tridentate mandibles; tridentate protibiae; and metatibial apex with four small teeth.The life histories of the species remain unknown.
The small genus Microphileurus (Fig. 4b) contains two small species from South America, one known from Brazil and Argentina and the other rare species known from Peru.Species in the genus are characterized by tridentate mandibles, obtusely acuminate clypeal apex, and frons with two small tubercles.
Mictophileurus is another monobasic phileurine genus, with only the southern Brazilian M. punctulatus Ohaus, 1911 as its included species.It shares many morphological characteristics with other genera of phileurines but can be distinguished by a combination of an acuminate clypeus; broad mandibles angled laterally; long, broad, and deep longitudinal pronotal furrow with a shallow fovea on each side; elytral intervals strongly convex; tridentate protibiae; metatibial apex with four small teeth; and form of the parameres.The natural history and immature stages of the species are unknown.
Oryctophileurus (Fig. 4c) contains four uncommon species found in Colombia, Peru, and Bolivia, which are characterized by tridentate mandibles; the presence of a horn or large tubercle on the frons; and quadridentate protibiae (Gasca-Á andAmat-G 2010, Perger andGrossi 2013).The immature stages and life history remain unknown for all species.

Palaeophileurus Kolbe, 1910
Palaeophileurus Kolbe 1910: 335.Kolbe (1910) described Palaeophileurus (Fig. 4d) for a single species, Phileurus sclateri (Bates, 1887), from Guyana.The genus now has ten species distributed only in South America (Ratcliffe 1988, 2002, Dechambre 1997, Dupuis 2012a, Neita and Ratcliffe 2012, 2017).Dechambre's (1997) P. panamensis, supposedly from Panama, is an erroneous country record because the type specimen is actually from Leticia, Amazonas, Colombia.Dechambre (1996b) proposed three new species but did not include a description of the species.All of these names are nomina nuda because they were not accompanied by a description or diagnosis in words as required by Article 13a (i) of the International Code of Zoological Nomenclature that was in effect at that time or by the most recent code (Article 13.1.1)(International Commission on Zoological Nomenclature 1985, 1999).Dechambre (1997) corrected this oversight by proposing the names again but accompanied by a brief description of each.The date for those three species, therefore, is 1997 and not 1996.
Species of Palaeophileurus are characterized by two adjacent tubercles on the head with the surface slightly concave between the tubercles; pronotum lacking a median furrow, fovea, or tubercle; nearly smooth, opaque black elytra; metatibial apex with a single apical tooth; simple basal metatarsomere; and long, stout prosternal process with a trilobed apex.Specimens of Palaeophileurus are usually uncommon, although occasionally locally abundant.Their rarity may result from genuinely small and/or dispersed populations or inadequate methods for attracting or collecting them.A few specimens have been attracted to lights, but, in our experience, phileurines are not as readily attracted to lights as are many other dynastines.
Paraphileurus (Fig. 5a) is a small genus comprised of only three species, all of which are known from northern South America, with one species reaching Panama (Ratcliffe 2003a).Paraphileurus is similar to Hemiphileurus but is distinguished by the presence of a broadly foveate pronotal cavity with an apical tubercle.In Hemiphileurus, the longitudinal furrow of the pronotum varies from indistinct to broad and from shallow to narrow and deep but never wid-ened anteriorly into a broad depression nor with an apical tubercle.In addition, Paraphileurus has a prosternal process that is produced posteriorly into a large, conical knob.
The life history and immature stages of the species are unknown.Endrödi (1978Endrödi ( , 1985) ) provided the most recent synopsis of the genus.
Phileurus species are characterized by a sharply acuminate clypeus; slender, externally arcuate mandibles; pronotum with a longitudinal furrow, subapical tubercle, and fovea or declivous area; and the apical margin of the metatibia with the dorsal angle produced into a single large, acute tooth or two teeth.Most of the species are moderately large beetles, with only some specimens of P. valgus (Olivier, 1789) measuring less than 20 mm in length.
The larval stage is described for only two species in the genus, P. didymus (Linnaeus, 1758) and P. valgus (under the name P. castaneus [Haldeman, 1843]) (Ritcher 1966).The natural history of Phileurus species is largely unknown.Adults and larvae have been collected from rotting logs and stumps (Ritcher 1966;BCR and RDC personal observations), where the larvae probably feed on decaying wood and/or associated fungi.Adults are frequently encountered at lights.Adults have been observed beneath streetlights in Mexico, where they were tearing open and feeding on the abdomens of Heterogomphus chevrolatii Burmeister, 1847 (Scarabaeidae: Dynastinae) (Ratcliffe and Morón 1997).McCleve (2007) observed an adult female on the branch of a tree where it was feeding on a lepidopteran larva.Albert Thurman (personal communication to BCR, June 2015) posted a video (www.youtube.com/watch?v=AY-dcJWvS-P0) of a Phileurus adult, probably P. truncatus (Palisot de Beauvois, 1806), feeding on a large dung beetle (Dichotomius species) in Panama.Adults of P. carinatus Prell, 1914 were observed consuming an adult female Golofa eacus Burmeister, 1847 after both were confined together in a terrarium in Ecuador (Ratcliffe et al. 2020).These observations demonstrate that some phileurine adults are predaceous.Little else is known of their natural history.
The genus Planophileurus (Fig. 5c) contains three species known from Cuba, the Bahamas, and the Dominican Republic (Ratcliffe and Cave 2015).Planophileurus species are noticeably dorsoventrally flattened relative to most other phileurines, and males are distinguished from all West Indian phileurines by their enlarged protarsal claws.
The frons has two nearly obsolete tubercles, the pronotum lacks a longitudinal furrow (a row of punctures at most), the basal bead is obsolete in front of the scutellum, the prosternal process is large and bulbous, male tarsomere four usually has a small ventral lobe that projects forward beneath tarsomere five, male tarsomere five is short and slightly to distinctly enlarged, and the medial claw is usually enlarged.
The females are best identified by association with the males when collected but also by their broadly oval pronotum that is reminiscent of the shape seen in species of Palaeophileurus from South America (best seen with comparative material).The natural history and immature stages for these rare beetles are completely unknown.
Their dorsoventrally flattened body form suggests they live under bark.

Chiliphileurus Endrödi, 1977
Chiliphileurus Endrödi 1977: 19.Ratcliffe et al. (2021) determined that the single species in this genus, Chiliphileurus tuberculatus Endrödi, 1977, is a junior synonym of the Asian Eophileurus cingalensis Arrow, 1908.The male holotype of C. tuberculatus is labeled "Valdivia, Chile" and, if correctly labeled, is a result of inadvertent commercial transport from Asia to Chile.
Chiliphileurus was removed from the list of American phileurines by Ratcliffe et al. (2021).Based on a detailed analysis of larval and adult characters, they transferred Platyphileurus from the Phileurini to the Oryctini and remarked that the flattened body shape was probably related to the beetle's unique habitat among tight bromeliad leaves, where larvae pupated and adults concealed themselves.Dupuis and Perrin (2020) suggested that the characters of Platyphileurus are closer to Cyclocephalini rather than Oryctini, and so definitive placement of this genus remains under study.
Dupuis and Dechambre, 2001 Allophileurinus Dupuis and Dechambre 2001: 201.Dupuis and Dechambre (2001) established Allophileurinus (Fig. 1b) to include two new species: A. cavifrons Dupuis and Dechambre, 2001 and A. mediopunctatus Dupuis and Dechambre, 2001, both from Ecuador (Ratcliffe et al. 2020).Allophileurinus species are characterized by a broadly subtriangular clypeal apex; smooth and shiny pronotum that lacks a median, longitudinal furrow; shiny, punctate-striate elytra; metatibia with two transverse carinae; and apical angle of the metatibia with a stout, triangular tooth.The form of the parameres for each species is unique.Members of Allophileurinus approach those of Paraphileurus in the form of the body, clypeus, frons, and prosternal process.Their life history is unknown.
indicated he saw a specimen from Colima, Mexico, but we remain unconvinced of the veracity of this record.Miguel Morón (personal communication to BCR, May 1997) said he knew of no Mexican records.Amblyodus species are easily recognized by their distinctive head horns and flattened pronotum.It is one of only two genera of phileurines in Central America whose species possess dentate mandibles and quadridentate protibiae, whereas species of Goniophileurus (the other genus whose much smaller species have dentate mandibles) have tridentate protibiae.
) described Moraguesia as a monotypic genus of Phileurini from French Guiana.Dupuis and Perrin (2020) transferred its species, M. champenoisi Dechambre, 2008, to Oxyligyrus Arrow in the Pentodontini.Platyphileurus Ohaus, 1910 Platyphileurus Ohaus 1910: 684.Ohaus (1910) created the genus Platyphileurus to accommodate a single species, P. felscheanus Ohaus, 1910.This species has an unusually flattened and posteriorly widened body form that may have suggested to Ohaus its phileurine affinities.After examining type specimens, Grossi et al. (2010) placed Surutu jelineki Endrödi, 1975 (Cyclocephalini) in junior synonymy with P. felscheanus and documented its occurrence in the Brazilian Atlantic Coastal Forest and Restinga biotopes in the Brazilian states of Bahia, Espírito Santo, Minas Gerais, Rio de Janeiro, Paraná, and Santa Catarina.In a detailed study, Albertoni et al. (2014) described the immature stages and life history of P. felscheanus.They repeatedly collected and reared larvae and pupae in bromeliad phytotelmata in Santa Catarina in southern Brazil.