Research Article |
Corresponding author: T. Keith Philips ( keith.philips@wku.edu ) Academic editor: Frank Krell
© 2016 T. Keith Philips.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Philips TK (2016) Phylogeny of the Oniticellini and Onthophagini dung beetles (Scarabaeidae, Scarabaeinae) from morphological evidence. ZooKeys 579: 9-57. https://doi.org/10.3897/zookeys.579.6183
|
A phylogenetic study was conducted to hypothesize relationships of most of the genera of the Oniticellini and Onthophagini for the first time using morphological characters from a diverse array of external and internal sclerites. The monophyly and sister relationship of both tribes was found using Bayesian and parsimony analyses with heavily to moderately weighted data. An alternative hypothesis based on parsimony analyses of unweighted or slightly weighted data show a paraphyletic Oniticellini without the Onthophagini, although recognition of the subtribe Helictopleurina as a tribe would eliminate non-monophyly.
Of the three Oniticellini subtribes, the Helictopleurina and Drepanocerina are monophyletic. There is no support for the monophyly of the Oniticellina or the Onthophagini subtribe Alloscelina, as currently defined. The genus Liatongus is paraphyletic, while strong support was found for monophyly of the Madagascan genus, Helictopleurus. The genus Onthophagus is never monophyletic in any analysis performed. Two new subtribes are also proposed: Liatonginasubtr. n. including the genus Liatongus and Attavicinasubtr. n. including the genera Attavicinus and Paroniticellus.
Topological evidence shows that the ancestral oniticellines and onthophagines were all coprophagous with alternative food sources evolving relatively recently. Both myrmecophily and termitophily probably evolved only once in the onthophagines. The phylogenetic analysis supports an African origin for the two tribes, with a relatively early age for the split of the Madagascar helictopleurines from the remaining oniticellines via dispersal. Furthermore, the presence of the oniticellines in the New World is hypothesized to be due to two relatively old dispersal events via Beringia and two relatively recent trans-Atlantic invasions of the Caribbean.
Parsimony, Bayesian, biogeography, tribe, subtribe, new taxa
The Oniticellini and Onthophagini contain close to one half of the roughly 7,000 species of scarabaeine dung beetles known worldwide (Schoolmeesters et al. 2010). Undoubtedly more species remain undocumented, perhaps as many as 1,000 or more, and certainly a large proportion of those, when described, will be placed in either the speciose onthophagine genus Onthophagus or another closely related group. In one estimate, Onthophagus alone contains 1765 species (
Many Oniticellini and Onthophagini (generic classification in Table
Generic classification of the Oniticellini and Onthophagini with the number of species in each genus currently recognized in the far right column. Taxa in bold are included in this study.
Tribe Oniticellini Kolbe, 1905 | |||
Subtribe Drepanocerina van Lansberge, 1875 – 12 genera, 53 spp. (+ 1 extinct sp.) | |||
Afrodrepanus | Krikken | 2009 | 2 |
Clypeodrepanus | Krikken | 2009 | 3 |
Cyptochirus | Lesne | 1900 | 4 |
Drepanocerus | Kirby | 1828 | 5 |
Drepanoplatynus | Boucomont | 1921 | 1 |
Eodrepanus | Barbero, Palestrini and Roggero | 2009 | 9 |
Epidrepanus | Roggero, Barbero and Palestrini | 2015 | 3 |
Ixodina | Roth | 1851 | 5 |
Paraixodina | Roggero, Barbero and Palestrini | 2015 | 3 |
Latodrepanus | Krikken | 2009 | 3 |
Sinodrepanus | Simonis | 1985 | 8 |
Tibiodrepanus | Krikken | 2009 | 7 |
Subtribe Oniticellina Kolebe, 1905 – 12 genera, 75 spp. | |||
Anoplodrepanus * | Simonis | 1981 | 2 |
Attavicinus | Philips and Bell | 2008 | 1 |
Euoniticellus | Janssens | 1953 | 19 |
Liatongus | Reitter | 1893 | 45 |
Nitiocellus | Branco | 2010 | 2 |
Oniticellus | Serville | 1828 | 10 |
Paroniticellus | Balthasar | 1963 | 1 |
Scaptocnemis ** | Péringuey | 1901 | 1 |
Scaptodera # | Hope | 1837 | 1 |
Tiniocellus | Péringuey | 1901 | 6 |
Tragiscus | Klug | 1855 | 1 |
Yvescambefortius | Ochi and Kon | 1996 | 1 |
Subtribe Helictopleurina Janssens, 1946 – 2 genera and ~ 81 spp. | |||
Helictopleurus | d’Orbigny | 1915 | 62 |
Heterosyphus | Paulian | 1975 | 1 |
Tribe Onthophagini Burmeister, 1846 – 36 genera and ~ 2500 spp. | |||
Subtribe Alloscelina Janssens, 1949 – 3 genera and 43 spp. | |||
Alloscelus | Boucomont | 1923 | 4 |
Haroldius | Boucomont | 1914 | 38 |
Megaponerophilus*** | Janssens | 1949 | 1 |
Remaining 33 genera | |||
Amietina | Cambefort | 1981 | 4 |
Anoctus | Sharp | 1875 | 5 |
Caccobius | Thomson | 1859 | 89 |
Cambefortius | Branco | 1989 | 8 |
Cassolus | Sharp | 1875 | 9 |
Cleptocaccobius | Cambefort | 1984 | 24 |
Cyobius | Sharp | 1875 | 5 |
Diastellopalpus | Van Lansberge | 1886 | 33 |
Digitonthophagus | Balthasar | 1959 | 2 |
Disphysema | Harold | 1873 | 1 |
Dorbignyolus | Branco | 1989 | 1 |
Euonthophagus | Balthasar | 1959 | 26 |
Eusaproecius | Branco | 1989 | 7 |
Heteroclitopus | Péringuey | 1901 | 10 |
Hyalonthophagus*** | Palestrini | 1989 | 9 |
Krikkenius | Branco | 1989 | 1 |
Milichus | Péringuey | 1901 | 16 |
Mimonthophagus | Balthasar | 1963 | 8 |
Neosaproecius | Branco | 1989 | 2 |
Onthophagus | Latreille | 1802 | 2000–2500 |
Phalops | Erichson | 1847 | 38 |
Pinacopodius | Branco | 1989 | 2 |
Pinacotarsus | Harold | 1875 | 2 |
Proagoderus | Van Lansberge | 1883 | 73 |
Pseudosaproecius | Balthasar | 1941 | 12 |
Stiptocnemis | Branco | 1989 | 2 |
Stiptopodius | Harold | 1871 | 11 |
Stiptotarsus | Branco | 1989 | 3 |
Strandius*** | Balthasar | 1935 | 17? |
Sukelus* | Branco | 1992 | 1 |
Tomogonus | d’Orbigny | 1904 | 11 |
Unidentis*** | Josso and Prévost | 2012 | 1 |
Walterantus | Cambefort | 1977 | 1 |
The Onthophagini contain approximately 35 genera, the number depending upon the chosen taxonomic classification (
Inconsistencies in the classification of these two tribes have been frequent. For example, nine of the 35 generic level onthophagine taxa were formerly placed in Dichotomiini (
Based on evidence of relationships within the Scarabaeinae from a wide range of morphological characters (
The 41 ingroup species, including many rare taxa, represent the morphological and behavioral diversity found within these two tribes reasonably well (Table
Ingroup | |
Oniticellini: | |
Helictopleurina: | |
Helictopleurus quadripunctatus Olivier | Madagascar |
Helictopleurus giganteus Harold | Madagascar |
Helictopleurus neoamplicollis Krell | Madagascar |
Drepanocerina: | |
Scaptocnemis segregis Péringuey | East Africa |
Cyptochirus ambiguous (Kirby) | South Africa |
Afrodrepanus impressicollis (Boheman) | South Africa |
Oniticellina: | |
Anoplodrepanus reconditus (Matthews) | Jamaica |
Tragiscus dimidiatus Klug | South Africa |
Paroniticellus festivus Steven | Turkey |
Oniticellus pictus (Hausmann) | South Africa |
Euoniticellus intermedius (Reiche) | South Africa |
Liatongus militaris Castelnau | South Africa |
Liatongus californicus (Horn) | USA |
Attavicinus monstrosus (Bates) | Mexico |
Tiniocellus spinipes Roth | South Africa |
Onthophagini: | |
Alloscelina: | |
Alloscelus paradoxus Boucomont | Haut-Uele, Moto, DRC |
Haroldius convexus (Philips & Scholtz) | South Africa |
Subtribe undefined: | |
Amietina eburnea Cambefort | Ivory Coast |
Caccobius ferrugineus Fahraeus | Botswana |
Cassolus humeralis Arrow | Mangpo, Darjeeling, India |
Cleptocaccobius schaedlei (d’Orbigny) | Kenya |
Diastellopalpus thomsoni Bates | Malawi |
Digitonthophagus gazella (Fabricius) | South Africa |
Euonthophagus sp. | South Africa |
Eusaproecius tinantae (Boucomont) | DRC |
Heteroclitopus annamariae Branco | Nigeria |
Hyalonthophagus alcyon (Klug) | South Africa |
Megaponerophilus megaponerae Brauns | Lulua, Sandoa, DRC |
Milichus apicalis Fahraeus | South Africa |
Mimonthophagus hinnulus (Klug) | Madagascar |
Onthophagus depressus Harold | South Africa |
Onthophagus hecate (Panzer) | North America |
Onthophagus capella Kirby | Australia |
Phalops sp. | South Africa |
Pinacotarsus dohrni Harold | Haut-Uele, Paulis, DRC |
Proagoderus lanista Castelnau | South Africa |
Pseudosaproecius validicornis Quedenfeldt | Tanzania |
Sukelus jessopi (Branco) | Kenya |
Stiptopodius doriae Harold | Gemu-Gofa Prov., Ethiopia |
Strandius lenzi (Harold) | Japan |
Tomogonus crassus (d’Orbigny) | Masinga (Mayombe), DRC? |
Outgroups | |
Eurysternini: | |
Eurysternus sp. | Costa Rica |
Sisyphini: | |
Sisyphus sp. | South Africa |
Onitini: | |
Onitis fulgidus Klug | South Africa |
To test generic monophyly, the study included three species of the Madagascar endemic Helictopleurus (from three species groups), two species of Liatongus Reitter (an Old and New World representative), and three species of Onthophagus Latreille (one endemic each from North America, Africa, and Australia). Three outgroup taxa were used to polarize character evolution in the ingroup and included a representative from the Onitini, Eurysternini, and Sisyphini. Previous analyses of the entire subfamily using morphology (
Dried specimens were initially relaxed in hot water and then cleared using lactic acid. Individual sclerotized body parts were observed on slides in glycerine and some of the larger structures were studied dry. An attempt was made to discover as many characters as possible from the various sclerotized structures without any bias as to what might be phylogenetically informative. Characters were only excluded if discrete states could not be adequately defined or if they were autapomorphic within a binary character. Five genitalic characters were used and more could have been included (as some recent dung beetle studies have done (e.g.,
For the parsimony analysis, WinClada (
Anoplodrepanus |
0011121123122102100110101131111101111201011101?201000?????02---2110011111100101000121??11101010101111111111010101120011002110111100211 |
Cyptochirus |
001001113312210210101010123111111111101120111131011101121112-1221100110011101113001211011101010100111101110111111121111002110111100111 |
Afrodrepanus |
00110201421221021011100012311111111110112111113100100112111010221100110111001110001210011101010100111100111110101121111110110111100201 |
Euoniticellus |
02011110531221021001101002311011111110010111110-012001221102---20100111111001113001211111101010111111111110010111121011002110111100211 |
Helictopleurus_quadripunctatus |
001101103312210210111011122111110010121021112110014101121002---21101110110001011010111110001010111110111110010101121011101111111111111 |
Helictopleurus_giganteus |
001000103310210210111011122110110110121021112110012201121102---21101111110001011010111110001010111110111110110101121011101121111111111 |
Helictopleurus_amplicollis |
00110110331221001?111010023102111101101011112131012301121102---21101110110001010011011110001010111110111100111101121011102121111111211 |
Liatongus_californicus |
001001112312210010001010023111111011101111112101011100221102---21100110111011013010211011101010111111111110210101121011102110111101101 |
Liatongus_militaris |
001010113312210011111010023101101011101111112111011101121002---20100110111001010011211000101010001111101110212110121011102110111101211 |
Liatongus_monstrosus |
001010111311210210111010023112132011121121112111011101121002---21101111111102013000210011001010111110111110113111021111102110111111211 |
Oniticellus |
001011112312210210201010023111101111100101112132011101121102---20101110111011110001111100101010011111101110311110121001002110111111211 |
Paroniticellus |
001010112312210210111010023110110011101021111131011401121102---21101110010101011001210001101010001111101110110111021111102110111111111 |
Scaptocnemis |
00101011311221021001101002311011001110110011113201100022??12-022110011011001111301121111110101111110110111011211112101100211011110121? |
Tiniocellus |
0011121123122102101010101131101?0011101100112132011001121102---20111010110001111011211101101010011101101110011101121011002110111101211 |
Tragiscus |
0010?00101112102100010100231111?111110110111210-011211121002---1110111011101111300121101110101011111110111031211002100101211011111121? |
Haroldius |
00111220731200011?11101011311211110102112?11013211060012??101020111110111?320013211211110111210111111011111412001021211601102101111011 |
Alloscelus |
111011106012010210301112123112101111111101110132103001121012-022110111111?020003111111111110000111111110111112111000111201106001110010 |
Amietina |
01111200331221001030101001301110110102112211013210300?????12-020111111011100001311101??11111010111111110111112111100111241106011111110 |
Caccobius |
02111210731221021010101002310010010112112011211110?020121012-1221100111110002013010211011001010111110110101112111100111301100111111111 |
Cassolus |
0000021002122002001013101031121111010211221131?211053?????101020111111111102011311101??10101310111011011111112011001111641105001111110 |
Cleptocaccobius |
021112007312210010101000013111100121121120110132105000221111-0201110111010002013011111111101010111111110101112111100111201100111111111 |
Diastellopalpus |
001013101210210210111010020113000121121111012111014101121112-201110111110100101301021101100101011111111010111211111011150100311111111? |
Digitonthophagus |
100010102112210000011010113110120111121111102131013201121112-1211101111110101013010201011001010111111111101112111110011301100111111111 |
Euonthophagus |
001112103212210210411010023100110101121101102131003101121012-022110111011000201201111111010101011111111011111211110011130110011111111? |
Eusaproecius |
021112103012110211410010101112131101111111110032103121121012-1221001101110020013001211111121200111111110111112111100111201100111111111 |
Heteroclitopus |
021112103002111210?1100010311211?111111101110032103321121012-0221111101110?20003001011110121201111111110111112111100111201100110011011 |
Hyalonthophagus |
121002107112210210011010023100100121121111012131003400221012-0021001110010002013010011111101010110110110111112111100110701100111111111 |
Megaponerophilus |
03111200?312010110101000113101100111011101112031103401121012-1201111101110221113111211111111200111111110111112111000111701106101111110 |
Milichus |
031112207312210200211010023001100121121101102131003021121012-1201101111010002013000211011101010111110110111112111110111341100111111111 |
Onthophagus_capella |
121101106210210210501111123112110111121111102131016100121012-0221101111001002013010111010101010111110110101102111110111301100111111111 |
Onthophagus_depressus |
000111108312210010011010113112010111121111100131003201121112-0221111110110102013000011011101010111111110101102111100111201100111110011 |
Onthophagus_hecate |
021112107212210010211010113111110111121111104131004400221012-1221001110111032010010011011001010111110110101112111100111201100111111111 |
Onthophagus_sp. |
020112204312210200101010013100100111121101112121103100221112-0211111011110102013011011011101010011111110101102111100111301100111111111 |
Phalops |
001002112112210200011010113111110100121111104011011201121012-0011001110110101010000211011101010111111111101112111121110341100111011111 |
Pinacotarsus |
0211121030121102013100121011121421111111?1110032103101121012-0201111101110000003001011111121100111111111111111111100111401100110111011 |
Proagoderus |
00100210231221021051101002311112010112110111211-016101121112-1211001110010001010011011011001010111110011111112111001111501100111111111 |
Pseudosaproecius |
0211121070120102000101101031121?110112111111013110?00112101210221101111110320?13011011011110200111111111111112111100111301100111111011 |
Sukelus |
021112101002211211310012101112152111111111100032103100121012-020110110111???0?03011211111121200111111110111112111100111201100110011011 |
Stiptopodius |
0211111030121112013102121011121?2101121121110032103021121012-0221111101110020013001111111121100111111111111112111100111201100101111011 |
Strandius |
121111108312210200411110113111100111121111102130004100211012-0021101110010002012010211010101010111110111111113111110111301100111111111 |
Tomogonus |
1111111093122000101011101130111001211211111021?110300?????12-122110111111002201301121??1110101011121011111111?111100111301106111111011 |
Eurysternus |
1001121003122101021112100131041?01010211201121320055302101100112110111111030001311101111110101111111111101051011113001183011601111011? |
Onitis |
002001110312210213111110023114100121021121112110016200000112-0221101111110001013000201111001010111011111110512111030011820014111111111 |
Sisyphus |
03111210731221021011112012311210011102112211113200220000011001121101110110000013100011111101011111111111011014001130011951106011110101 |
Piwe weighting (parsimony with implied weighting) in TNT (
Weighting in morphological analyses has been considered unscientific by some (e.g.,
The standard model for morphological data and the default set of priors were used in the Bayesian analysis (Mr. Bayes version 3.2.1 for Windows 32 bit) (
Posterior probability node support is shown on the tree from the Bayesian analysis. Bootstrap values were calculated in TNT from 1000 replicates using sampling with replacement, the traditional tree search setting, and collapsing of groups below a value of 1. Values are displayed at all nodes where support is at or above 0.5 or 50%. Consistency and retention indices (CI and RI) derived from unweighted data (Figs
Biogeographic analysis was done using a Dispersal-Vicariance Analysis (
Brief discussions on the evolution of morphology, nesting behavior, food sources, and biogeography are based on the best supported hypotheses of evolution. Rather than inclusion in the discussion, Table
Character support for selected clades, unweighted or weighted (K value =10) data.
Character support: Onitini, Oniticellini, and the Onthophagini monophyly (unweighted data) |
Uncontroverted synapomorphies: |
1) pygidium median groove absent (59-2); |
2) propygidium transversely with an even width (61-0); |
3) propygidium posterior/ventral border medially without either an angulate emargination anteriorly or rounded shape posteriorly (62-2); |
4) elytral striae composed of a single line (94-0); |
5) cervical lateral sclerite apex lacking a lateral pocket or cavity (104-1); |
6) meso- and metatibia broad and greatly expanded apically (125-1); |
7) metatibia not elongate and parallel sided at middle ½ (130-1). |
Controverted synapomorphies: |
8) cephalic projection consisting of a central horn positioned posteriorly (46-1); |
9) eye canthus completely dividing eye (49-1); |
10) ventral lacinial articulation sclerite with a short “tail” extending only part of length (76-1); |
11) four teeth on the protibia; (80-0); |
12) pronotal posterior margin with a slight but distinct posteriorly directed point or angulate edge (89-0). |
Character support: Oniticellini + Onthophagini monophyly (unweighted data) |
Uncontroverted synapomorphies: |
1) labial palps with the third palpomere reduced in size and appearing as having only two palpomeres (21-0); |
2) mentum paraglossal strut laterally at distal apex expanded but not bifurcate (29-1); |
3) angle of parameres to basal piece where attached approximately 45 degrees (54-1); |
4) length of parameres to basal piece, excluding narrow projections approximately ½ the length of basal piece (55-2); |
5) dorsal plate of the genital capsule oriented transversely (56-1). |
Controverted synapomorphies: |
1) mentum glossal lobe narrowly rounded (31-1); |
2) the antennae with vessicles present and easily visible (36-1); |
3) blunt paramere apex (53-1); |
4) mesonotum with the prescutum anteriorly transverse plate approximately ventrally directed and angularly emarginate (107-1); |
5) mesocutum lateral projection extended with a pointed apex (114-2); |
6) mesoscutum lateral edge lacking a pocket (115-1); |
7) metascutellum posterior edge with a slight margin or remnant edge (119-1). |
Character support: Oniticellini + Onthophagini monophyly (weighted data, k = 10) |
Uncontroverted synapomorphies: |
1) labial palps with the third palpomere reduced in size and appearing as having only two palpomeres (21-0); |
2) angle of parameres to basal piece where attached approximately 45 degrees (54-1); |
3) length of parameres to basal piece, excluding narrow projections approximately ½ the length of basal piece (55-2); |
4) dorsal plate of the genital capsule oriented transversely (56-1); |
5) wing AA vein posteriorly forming a cell partially closed with extension toward costal margin (8-2). |
Controverted synapomorphies: |
1) antennae with vessicles present and easily visible (36-1); |
2) blunt paramere apex (53-1); |
3) mesonotum with the prescutum anteriorly transverse plate approximately ventrally directed and angularly emarginate (107-1); |
4) paraglossal strut laterally at distal apex expanded, but not bifurcate (29-1); |
posterior margin of the gula on the head truncate and slightly projecting (51-1). |
Character support: Oniticellini monophyly (weighted data, k = 10) |
Uncontroverted synapomorphies: |
1) pygidium lacks a transverse ridge defining or separating the propygidium from the pygidium (58-0). |
Character support: Onthophagini monophyly (unweighted data) |
Uncontroverted synapomorphies: |
1) scutellum (metanotum) posterior margin with a short apical projection and with a truncate apex and laterally with rapidly converging sides (119-5). |
Controverted synapomorphies: |
1) dorso-lateral edge of propygidium angulate and not rounded; (63-1); |
2) mesonotum scutellum apex triangular shaped (106-1); |
3) prescutum-scutum junction when viewed in a horizontal position broadly rounded (109-2); |
4) mediophragma of the metanotum with a distinct longitudinal ridge (123-0). |
Character support: Onthophagini monophyly (weighted data, k = 10) |
Controverted synapomorphies: |
1) dorso-lateral edge of propygidium angulate, and not rounded (63-1); |
2) the scutellum (mesonotum) apex triangular shaped (106-1); |
3) prephragma of the prescutum (mesonotum) in ventral view recurved in shape (116-1); |
4) mediophragma (metanotum) with a distinct longitudinal ridge (123-0). |
Onthophagini clade 1 support: Haroldius + Cassolus through to Sukulus (unweighted data) |
Uncontroverted synapomorphy: |
1) apical extension of pigmented mesal comb compared to sclerotized (darkened) area near opposite lateral edge approximately the same length or slightly shorter; (92-2). |
Controverted synapomorphies: |
1) mentum length approximately equal to width (24-1); |
2) inner strut of lacinia (nearest to palpifer), distal tip, notch absent and tapered tip (75-2); |
3) scutum distinctly transverse (113-0); |
4) metatarsi: length of first metatarsis compared to second: first nearly 2X or more the length of second (126-0). |
Onthophagini clade 2 support: Megaponerophilus through to Sukulus (unweighted data) |
Uncontroverted synapomorphies: |
1) proximal antennomere of the apical club in lateral view (~4 to 5 times as long as wide) (37-1); |
2) mandibular cuticle on the lateral edge and part of ventral surface bright chestnut red color (93-0). |
Controverted synapomorphies: |
1) prothoracic apodemes with a complete oblique suture (40-0); |
2) apex of the paramere blunt and not pointed (53-1). |
Oniticellini clade 1 support: Helictopleurina (unweighted data) |
Controverted synapomorphies: |
1) prothoracic apodeme with a large flattened single flange and with one lateral edge slightly expanded perpendicularly (39-0) [only seen elsewhere in Paroniticellus]; |
2) pronotal surface glabrous (88-0); |
3) elytral seventh stria strongly curved (100-0); |
4) anterior margin of scutum with an pale colored, transverse region of cuticle (111-0). |
Oniticellini clade 2 support: Drepanocerina: Cyptochirus + Afrodrepanus (unweighted data and weighted data, k = 10) |
Controverted synapomorphies: |
1) anal region of wing with a posterior notch (4-0); |
2) apodeme of cervical sclerite lacking a carina (40-2); |
3) a single carinae anterior of eyes (47-1); |
4) a transverse ridge defining or separating propygidium from the pygidium present (58-1); |
5) Elytral umeral angle in dorsal view with a lateral bulge (97-0); |
6) Mesonotum prescutum: prephragma in ventral view with recurve present (116-1). |
Oniticellini clade 3 support: Oniticellina and Drepanocerina (unweighted data) |
Controverted synapomorphies: |
1) RA vein extension along apical margin relatively great (7-1) [only seen elsewhere in Phalops and Onitis]; |
2) internal apodeme (V or Y shaped usually with one arm relatively short) adjacent to paraglossal apodeme in dorsal view, from anterior to posterior obliquely angled outwards (33-0) [only seen elsewhere in Helictopleurus quadripunctatus]. |
Oniticellini clade 4 support: Attavicinus + Paroniticellus (unweighted data) |
Controverted synapomorphies: |
1) internal accessory sclerite within the maxilla that is curved near the proximal end (74-1); |
2) the protibia on proximal side with a line of setae associated with a carina (81-0); |
3) males with two postero-lateral ridges on the pronotum (85-0); |
4) scutum distinctly transverse (113-0). |
Oniticellini clade 5 support: Liatongus californicus to Euoniticellus (unweighted data) |
Uncontroverted synapomorphies: |
1) metacoxal separation at middle relatively large (129, 0), uncontroverted. |
Controverted synapomorphies: |
2) labium internal apodeme adjacent to paraglossal apodeme in dorsal view, from anterior to posterior, appearing V shaped (32, 1); |
3) visible portion of the first ventrite projecting between metacoxae distinctly truncate at apex (67, 0). |
0. AA vein: (0) with a remnant cross vein and appearing as a small “T” proximally; (1) lacking remnant cross vein. CI = 0.16, RI = 0.16.
1. MP vein length compared to RP: (0) normal (long), approximately 30% or more the length of the RP; (1) intermediate, approximately 20–30% the RP length; (2) short, only near margin and not extending backwards (less than 20% the RP length); (3) MP vein absent. CI = 0.30, RI = 0.58.
2. Pigment patch near apical 1/3: (0) absent; (1) present and distal edge perpendicular to longitudinal axis of the body (Note that the patch is sometimes poorly defined; (2) present and distal edge oblique. CI = 0.28, RI = 0.0.
3. Anal region: (0) large and well developed (noticeably expanded); (1) lacking this shape. CI = 0.10, RI = 0.43.
4. Anal region posterior notch: (0) present; (1) absent. CI = 0.11, RI = 0.27.
5. Jugal and AP vein: (0) both present; (1) AP only; (2) both absent; (3) jugal only. CI = 0.17, RI = 0.22.
6. MP vein near posterior margin of wing: (0) straight to very slightly curved; (1) distinctly, strongly curved; (2) does not reach margin. CI = 0.20, RI = 0.0.
7. RA vein extension along apical margin: (0) slight, not reaching the margin; (1) great, reaching and running parallel to margin for part of its length. CI = 0.25, RI = 0.75.
8. AA vein posteriorly (near wing base): bridge vein extension towards CuA vein: (0) forming cell that is completely closed; (1) forming cell partially closed and extending on both sides of AA and AA vein with small break; (2) forming cell partially closed and with extension toward costal margin but large break on AA vein; (3) cell broadly open, bridge vein absent; (4) forming cell slightly closed with bend towards costal margin; (5) forming cell slightly closed and proximal end of bridge vein detached from AA vein; (6) cell bridge vein complete but cell partially open due to break in AA vein; (7) cell absent (lacking bridge vein) and AA vein smoothly curved; (8) cell partially closed with bridge vein not reaching CuA vein; (9) cell absent (bridge vein absent) with vein slightly sigmodal in shape. CI = 0.39, RI = 0.36.
9. Apical margin: (0) broadly emarginate and not projecting medially; (1) narrowly, smoothly emarginate medially; (2) projecting medially; (3) approximately truncate. CI = 0.25, RI = 0.40.
10. Pigmentation: (0) extremely heavy and dark colored; (1) heavy and dark color absent. CI = 0.50, RI = 0.0.
11. Lateral comb (chaetopariae) apical extension: (0) to or near lateral margin; (1) to front margin first and curving towards lateral margin; (2) distant from both front and lateral margin. CI = 0.40, RI = 0.0.
12. Lateral combs (chaetopariae): (0) relatively parallel and straight but curving slightly inwards apically; (1) relatively parallel and straight throughout; (2) curved throughout. CI = 0.50, RI = 0.66.
13. Anterior median ventral process base (crepis): (0) long (length much longer than width; (1) short (length approximately equal to width). CI = 0.50, RI = 0.50.
14. Anterior median ventral process basally (crepis): (0) distinct and triangular (sometimes elongately); (1) indistinct. CI = 0.50, RI = 0.50.
15. Posterior median tormal process (epitorma): (0) smoothly, broadly tapered throughout: (1) smoothly narrowly tapered; (2) more irregularly shaped. CI = 0.18, RI = 0.10.
16. Lateral tormal processes (apotorma): (0) without any obvious circular-shaped muscle attachment point proximally; (1) with attachment point(s). CI = 0.10, RI = 0.0.
17. Dark pattern on anterior half of ventral surface: (0) broadly triangular without any emargination on either side of peak; (1) moderately broadly triangular and with an emargination on either side of the peak; (2) triangular but with parallel sides at narrow base; (3) broadly rounded. CI = 0.60, RI = 0.50.
18. Cavity on dorsal side of proximal portion of epipharynx: (0) broadly emarginate; (1) flat to slightly rounded; (2) narrowly, sharply emarginate; (3) narrowly, gradually emarginate; (4) moderately, sharply emarginate; (5) small shallow emargination on either side of middle (two). CI = 0.27, RI = 0.27.
19. Base of anterior median process in dorsal view (crepis): (0) lateral projections visible; (1) projections lacking. CI = 0.11, RI = 0.38.
20. Coarse setae on ventral surface between combs (prophobae): (0) at middle only; (1) relatively evenly scattered throughout. CI = 0.50, RI = 0.75.
21. Third palpomere: (0) indistinctly and appearing as two, with the third very reduced in size; (1) distinctly as three, third only slightly reduced; (2)third absent; (3) third subequal to second. CI = 0.37, RI = 0.28. Note that in state “0,” the third palpomere is very tiny and difficult to observe. It appears though to be a tiny reduced palpomere.
22. Second palpomere shape: (0) distinctly rounded to transverse; (1) elongate; (2) triangular. CI = 0.40, RI = 0.0.
23. Mentum apical edge: (0) shallow V-shaped notch; (1) U-shaped notch; (2) smoothly rounded notch. CI = 0.40, RI = 0.40.
24. Mentum shape: (0) distinctly transverse; (1) length approximately equal to width. CI = 0.10, RI = 0.52.
25. Mentum oblique lateral edge: (0) no notch, steeply angled; (1) no notch, moderately angled; (2) notch present (slight to distinct). CI = 0.18, RI = 0.52.
26. Shape of anterior declivous region of mentum: (0) narrow and parallel sided; (1) elongate triangular shape with acutely pointed apex; (2) broad and parallel sided; (3) broad triangular shape with a broadly rounded apex. CI = 0.75, RI = 0.75.
27. Anterior declivous region of mentum apex: (0) with a dark lip; (1) dark lip absent. CI = 0.33, RI = 0.0.
28. Anterior declivous region of mentum: (0) projecting anteriorly with ventral surface horizontal; (1) or not. CI = 0.12, RI = 0.12.
29. Paraglossal strut laterally at distal apex: (0) expanded and bifurcate; (1) expanded but not bifurcate; (2) approximately parallel sided; (3) sigmoidal; (4) abruptly expanded near apex. CI = 0.22, RI = 0.39.
30. Palpomere strut apex adjacent to paraglossal strut: (0) expanded; (1) unexpanded. CI = 0.50, RI = 0.0.
31. Glossal lobe; (0) large and emarginate; (1) large and narrowly rounded; (2) large and broadly rounded; (3) large and triangular; (4) small and rounded; (5) absent. CI = 0.33, RI = 0.37.
32. Internal apodeme (V or Y shaped usually with one arm relatively short) adjacent to paraglossal apodeme in dorsal view, from anterior to posterior, appearing: (0) Y-shaped; (1) V-shaped; (2) straight, no arm present. CI = 0.25, RI = 0.62.
33. Internal apodeme (as in #32): (0) obliquely angled outwards; (1) longitudinally aligned; (2) obliquely angled inwards. CI = 0.33, RI = 0.66.
34. Internal apodeme, proximal apex: (0) enlarged; (1) not enlarged. CI = 0.12, RI = 0.12.
35. Most proximal apodeme, length from apex to transverse bridge: (0) long; (1) normal (approximately the same length as the width of the transverse bridge). CI = 0.50, RI = 0.50.
36. Antennal vessicles: (0) absent (or possibly obscure and difficult to see); (1) present and easily visible. CI = 0.33, RI = 0.66.
37. Proximal antennomere of the apical club viewed laterally: (0) about 50% longer than wide; (1) approximately 4 to 5 times as long as wide; (2) approximately two times as long as wide. CI = 0.28, RI = 0.66.
38. Apical flanges: (0) trilobed; (1) or not. CI = 0.50, RI = 0.50.
39. Apodeme: (0) with a large flattened single flange (with one lateral edge slightly expanded perpendicularly; (1) large flattened single flange absent. CI = 0.50, RI = 0.66.
40. Apodeme: (0) with a complete oblique suture/carina; (1) with an incomplete oblique suture/carina; (2) suture/carina absent. CI = 0.14, RI = 0.53.
41. Apodeme pocket: (0) deep and elongate; (1) no deep pocket, slight flanges at most. CI = 0.25, RI = 0.14.
42. Apodeme apex: (0) with a short second flange; (1) short second flange absent. CI = 0.50, RI = 0.0.
43. Apodeme shape: (0) broad, smoothly rounded; (1) lacking a broad and smoothly rounded shape. CI = 0.25, RI = 0.66.
44. Clypeal teeth: (0) two and juxtaposed; (1) two and broadly separated; (2) four; (3) single median. CI = 0.36, RI = 0.58.
45. Genal development: (0) strong, acutely angled or less; (1) weak, angle greater than 90 degrees. CI = 0.33, RI = 0.66.
46. Cephalic projections: (0) central horn anteriorly; (1) central horn posteriorly; (2) paired separate projections. CI = 0.30, RI = 0.30.
47. Carinae anterior of eyes: (0) two transverse carinae; (1) one transverse carina; (2) no carinae. CI = 0.22, RI = 0.61. Taxa that have a horn that obscures a carina if it was present were coded with a dash (-).
48. Transverse projection: horn or ridge posterior of eyes: (0) present; (1) absent. CI = 0.50, RI = 0.92. This ridge is located anterior of a second ridge, if present, demarking smooth usually hidden surface posterior from typically exposed part of the head.
49. Eye canthus: (0) not dividing eye; (1) completely dividing eye. CI = 0.20, RI = 0.80.
50. Head posterior margin, dorsally: (0) wide projection with broadly truncate apex; (1) medial moderate triangular projection approximately equal in size to emarginations on either side; (2) medial narrow triangular projection, much narrower than emarginations on either side; (3) medial broad triangular projection, larger than emarginations on either side; (5) medial broad and elongate triangular projection and with emarginations distally with slightly filled in with darken cuticle; (6) medial very broad projection with approximately equal and broad emarginations on either side. CI = 0.42, RI = 0.61.
51. Posterior margin of gula: (0) broadly rounded and strongly projecting; (1) truncate and slightly projecting; (2) shallowly emarginate at middle; (3) narrowly slightly projecting at middle; (4) broadly rounded and weakly projecting; (5) truncate but narrowly emarginate at middle; (6) narrowly strongly projecting at middle. CI = 0.27, RI = 0.30.
52. Setal pattern on anterior margin of gula: (0) transverse band; (1) elongate triangular shape with base positioned distally; (2) approximately equilateral triangle with base positioned proximally; (3) broad triangular shape with base positioned distally. CI = 0.37, RI = 0.0.
53. Paramere apex: (0) elongately pointed; (1) blunt. CI = 0.12, RI = 0.46.
54. Angle of parameres to basal piece where attached: (0) aligned at approximately same angle; (1) approximately 45 degrees; (2) approximately 90 degrees. CI = 0.20, RI = 0.11.
55. Length of parameres to basal piece, excluding narrow projections: (0) nearly equal to length of basal piece; (1) much greater than ½ the length of basal piece; (2) approximately ½ the length of basal piece. CI = 0.66, RI = 0.50.
56. Dorsal plate orientation: (0) vertical; (1) transverse. CI = 1.00, RI = 1.00.
57. Dorsal plate shape: (0) with distinct lateral projections or “tails;” (1) lateral projections lacking. CI = 0.12, RI = 0.58.
58. Transverse ridge defining or separating propygidium from the pygidium: (0) absent; (1) present. CI = 0.25, RI = 0.72.
59. Median groove: (0) distinct and with complete lateral edges; (1) present but indistinct; (2) absent. CI = 0.50, RI = 0.50.
60. Median groove on propygidium: (0) sides parallel; (1) sides converging. CI = 1.00, RI = 1.00.
61. Propygidium shape: (0) even width throughout; (1) longer medially (slightly); (2) narrowed medially. CI = 0.18, RI = 0.10.
62. Propygidium posterior/ventral border medially: (0) angulate emargination anteriorly; (1) rounded posteriorly; (2) none of the previous. CI = 0.40, RI = 0.25.
63. Dorso-lateral edge of propygidium: (0) with a lateral projection creating an overhanging edge; (1) not projecting and angulate, not rounded; (2) none of the previous. CI = 0.22, RI = 0.41.
64. Dark band of pigment at base: (0) present; (1) absent. CI = 0.25, RI = 0.0.
65. Propygidium length compared to width: (0) relatively broad; (1) or narrow. CI = 0.20, RI = 0.0.
66. First ventrite: (0) distinctly visible throughout entire length; (1) reduced to thin “line” near middle. CI = 0.16, RI = 0.50.
67. First ventrite visible portion projecting between metacoxae: (0) distinctly truncate; (1) not distinctly truncate. CI = 0.20, RI = 0.50.
68. Fifth ventrite, males: (0) reduced to a thin line at middle; (1) wider and obvious. CI = 0.50, RI = 0.0. Note: Males were lacking for Liatongus californicus, Anoplophora, Cassolus, Amietina, and Tomogonus and were coded as “?.”
69. Galea shape: (0) longer than wide; (1) wider than long. CI = 0.33, RI = 0.66.
70. Apical palpomere: (0) basal 2/3 distinctly darker than apical 1/3; (1) approximately the same shade throughout. CI = 0.80, RI = 0.42.
71. Dorsal articulatory sclerite: (0) projecting laterally as an acute point; (1) not projecting laterally as an acute point. CI = 0.14, RI = 0.14.
72. Ventral articulatory sclerite (‘V) of the galea (distal half) in dorsal view: (0) abruptly expanded from base to apex on galea brush side at middle; (1) expansion not abrupt but more gradual. CI = 0.50, RI = 0.0.
73. Ventral articulatory sclerite (‘V’) of the galea (proximal half) in dorsal view: (0) parallel sided or nearly so; (1) expanded at or near middle. CI = 0.12, RI = 0.46.
74. Accessory internal sclerite: (0) curved near distal end; (1) curved near proximal end; (2) straight. CI = 0.33, RI = 0.25. Two taxa, Heteroclitopus and Sukelus, were coded as “?” as the structure was too difficult to see clearly.
75. Inner strut of lacinia (nearest to palpifer), distal tip: (0) with notch (sometimes with one tooth greatly reduced); (1) with notch and with one tooth perpendicular to other; (2) notch absent and tapered tip; (3) notch absent and spatulate tip. CI = 0.42, RI = 0.63.
76. Ventral lacinial articulation sclerite (in ventral view): (0) lacking any extension or “tail;” (1) with a short “tail” extending only part of length; (2) with a long “tail” extending most of lacinial length. CI = 0.40, RI = 0.86.
77. Number of “extra” sclerites associated with the galea: (0) one or more; (1) absent. CI = 0.25, RI = 0.62.
78. Large sclerotized plate of the dorsal aticulation sclerite situated between arms of ventral articulatory sclerite (“V) of the galea: (0) present; (1) absent. CI = 0.33, RI = 0.33.
79. Ventral articulatory sclerite (‘V) of the galea, apex of distal arm: (0) truncate; (1) slightly emarginate; (2) bifurcate; (3) pointed or rounded. CI = 0.23, RI = 0.09.
80. Number of teeth on tibia: (0) four; (1) three; (2) two. CI = 0.50, RI = 0.60.
81. Tibia on proximal side opposite outer teeth: (0) with a line of setae associated with a carina; (1) setae absent. CI = 0.11, RI = 0.50.
82. Pronotum anterior opening dorsally: (0) with a slight indentation medially; (1) or more smoothly rounded. CI = 0.12, RI = 0.53.
83. Tibia between second and third teeth, number of microteeth: (0) two or three; (1) one; (2) none. CI = 0.11, RI = 0.15.
84. Male tibia: (0) elongate, narrow, and curved near apex; (1) relatively short, wide and straight throughout. CI = 0.50, RI = 0.0.
85. Male pronotal sculpture: (0) two posterio-lateral ridges; (1) or not. CI = 0.50, RI = 0.50.
86. Male pronotal projections or depressions: (0) present; (1) absent, surface smoothly rounded. CI = 0.12, RI = 0.61.
87. Pronotum with pale colored maculations: (0) present; (1) absent. CI = 0.25, RI = 0.0.
88. Pronotal surface: (0) glabrous; (1) setose, although sometimes only at or near edges. CI = 0.14, RI = 0.40.
89. Pronotum posterior margin dorsally: (0) with a slight but distinct posteriorly directed point or angulate edge; (1) edge rounded. CI = 0.14, RI = 0.33.
90. Apex, appearing (0) sharply acute; (1) narrowly rounded; (2) broadly rounded. CI = 0.66, RI = 0.87.
91. Outer lateral edge: (0) bulbous/expanded laterally; (1) no bulbous expansion laterally. CI = 0.50, RI = 0.0.
92. Apical extension of pigmented mesal comb compared to sclerotized (darkened) area near opposite lateral edge: (0) longer; (1) absent (not visible); (2) approximately the same length or slightly shorter; (3) approximately ¾ the length of the sclerotized area. CI = 0.60, RI = 0.66.
93. Outer lateral edge and part of ventral surface: (0) with bright chestnut red colored cuticle; (1) red colored cuticle absent. CI = 1.00, RI = 1.00.
94. Elytral striae: (0) composed of a single line; (1) composed of a three lines creating two rows (i.e., with a thin line separating two adjacent rows). CI = 0.33, RI = 0.33
95. Pigment patches: (0) dark elongate areas on some intervals adjacent to pale cuticle; (1) dark areas lacking. CI = 0.20, RI = 0.0.
96. First, third and fifth intervals: (0) slightly raised above surrounding intervals; (1) nearly the same height as the others. CI = 0.25, RI = 0.25.
97. Humeral angle in dorsal view: (0) with a lateral bulge; (1) bulge absent. CI = 0.50, RI = 0.50.
98. Epipleura: (0) double; (1) single; (2) indistinct. CI = 0.66, RI = 0.0.
Note in Tomogonus there is no distinct epipleura but the elytra are smoothly rounded to the lateral edge.
99. Eighth interval: (0) extending only approximately ½ the length of the elytron; (1) or not. CI = 1.00, RI = 1.00.
Note that in Scaptocnemis and Tiniocellus, the eight interval appears to be obsolete beyond the basal half.
100. Seventh stria: (0) strongly and distinctly curved inwards towards 6th stria near the elytral base; (1) slightly curved at most. CI = 0.16, RI = 0.54.
101. Shape at anterior margin: (0) rounded without or only a slight lateral protrusion; (1) or not. CI = 0.50, RI = 0.50.
102. Lateral margin near apex: (0) with a distinct beak-like tapered straight point; (1) tapered straight point absent. CI = 0.33, RI = 0.71.
103. Apex: (0) with a distinct darkened hook projecting ventrally; (1) hook projecting ventrally absent. CI = 0.11, RI = 0.50.
104. Apex with a lateral pocket or cavity: (0) present; (1) absent. CI = 1.00, RI = 1.00.
105. Apex, including muscle apodeme: (0) broadly rounded; (1) or not. CI = 0.16, RI = 0.44.
106. Scutellum apex: (0) elongate and parallel sided, tongue-shaped; (1) triangular shaped. CI = 0.25, RI = 0.78.
107. Prescutum anteriorly: transverse plate approximately ventrally directed: (0) narrow, parallel sided, needle-shaped; (1) angularly emarginate to various depths; (2) narrowly rounded; (3) short small projection; (4) flat, no projection; (5) broadly rounded. CI = 0.55, RI = 0.42.
108. Prescutum anteriorly transverse plate approximately ventrally directed: (0) with distal tips curved out laterally; (1) tips parallel or absent. CI = 0.33, RI = 0.0.
109. Prescutum-scutum junction when viewed in a horizontal position: (0) sharply emarginate; (1) broadly emarginate; (2) broadly rounded; (3) narrowly rounded at middle; (4) straight. CI = 0.33, RI = 0.33.
110. Scutum- scutellum, each sclerite: (0) on two different planes or levels (with a strong declivity between them); (1) on a single plane or level (declivity absent or weak). CI = 0.50, RI = 0.50.
111. Anterior margin of scutum: (0) with a pale colored, transverse region of cuticle; (1) pale colored transverse region absent. CI = 0.14, RI = 0.25.
112. Prescutum: prephragma (longitudinally directed median apodeme with scutum in a horizontal position: (0) with a transverse suture; (1) transverse suture absent. CI = 0.50, RI = 0.50.
113. Scutum: (0) distinctly transverse; (1) not distinctly transverse in shape. CI = 0.16, RI = 0.37.
114. Scutum lateral projection (0) extended only slightly and truncate; (1) distinctly extended and with a blunt apex; (2) extended and with a pointed apex; (3) projection absent. CI = 0.37, RI = 0.77.
115. Scutum lateral edge: (0) with a rounded or somewhat rounded lateral pocket; (1) pocket absent. CI = 0.20, RI = 0.76.
116. Prescutum: prephragma in ventral view: (0) recurve absent (and with longitudinal axis): (1) recurve present; (2) recurve absent (longitudinal axis absent to support recurve). CI = 0.40, RI = 0.78.
117. Scutellum ventral surface at apex: (0) with carina extending anteriorly through V-shaped sclerite; (1) carina absent. CI = 1.00, RI = 1.00.
118. Scutellum in ventral view: (0) triangular shaped and much less than ½ the width of the scutum; (1) or not. CI = 0.50, RI = 0.0.
119. Scutellum posterior margin: (0) no margin or edge; (1) slight margin or remnant edge; (2) short, round triangular projection (converging sides); (3) long triangular projection (parallel or subparallel sides for part of length); (4) short projection with truncate apex, gradually converging sides; (5) short projection with truncate apex, rapidly converging sides; (6) short projection, gradually converging sides with emarginate apex; (7) short triangular projection (converging sides) but truncate apex; (8) broad, subparallel projection with truncate apex; (9) short, sharp triangular projection (converging sides). CI = 0.64, RI = 0.80.
120. Scutellum anterior margin: (0) straight to very slightly projecting; (1) moderately projecting and broadly rounded; (2) sinuate; (3) truncate (rounded at anterio-lateral edges); (4) slightly emarginate; (5) strongly projecting and broadly rounded. CI = 0.55, RI = 0.0.
121. Alar ridge sides on scutellum excluding anterior projection towards posterior: (0) narrow in width and sides slightly converging basally; (1) wide and sides strongly converging basally; (2) wide and sides slightly converging basally. CI = 0.40, RI = 0.76.
122. Mediophragma, ventral margin cleft shape: (0) deeply emarginate (sides subparallel); (1) shallowly emarginate (sides obliquely angled). CI = 0.50, RI = 0.0.
123. Mediophragma: (0) with a distinct longitudinal ridge; (1) with a partial ridge (remnant easily visible); (2) ridge absent. CI = 0.50, RI = 0.86.
124. Mesosternum: (0) with a transverse and longitudinal low ridge forming a cross shape of various forms; (1) with a U shaped depression intersected by a longitudinal ridge; (2) with a transverse ridge with a very slight medial expansion anteriorly; (3) transverse ridge medially narrowly smoothly expanded ventrally; (4) with a longitudinal ridge expanded anteriorly; (5) with a transverse ridge expanded slightly anteriorly at middle forming a truncate anterior margin; (6) with a transverse ridge (in Amietina extending anteriorly gradually towards middle). CI = 0.66, RI = 0.57.
125. Meso- and metatibia: (0) narrow and only slightly expanded apically; (1) broad and greatly expanded apically. CI = 0.25, RI = 0.25.
126. Metatarsi: length of first metatarsomere compared to second: (0) first nearly 2X or more the length of second; (1) first only slightly longer than second. CI = 0.33, RI = 0.50.
127. First metatarsomere: (0) lengthened and greatly expanded laterally; (1) neither lengthened and expanded laterally. CI = 0.50, RI = 0.50.
128. First metatarsomere: (0) distinctly fringed on both lateral edges with dense combs of setae; (1) distinct setal fringes lacking. CI = 0.33, RI = 0.0.
129. Metacoxal separation at middle: (0) relatively large, coxae distinctly separated throughout and ventrite projection anteriorly at middle separating coxae truncate at apex; (1) relatively narrow, coxae not distinctly separated anteriorly, in contact or nearly so, ventrite projection pointed at apex. CI = 0.50, RI = 0.85. Note that this character appears to be quite variable within the Eurysternini.
130. Metatibia: (0) elongate and parallel sided at middle ½; (1) or not. CI = 0.25, RI = 0.57.
131. Metasternum between mesocoxae: (0) diverging anteriorly; (1) approximately parallel sided; (2) converging anteriorly. CI = 0.22, RI = 0.58.
132. Metasternum posteriorly: (0) with a shallow depression; (1) depression absent. CI = 0.33, RI = 0.0.
133. Metendosternite basal stalk: (0) sides diverging throughout length; (1) sides parallel (sometimes slightly sigmoidal) to slightly converging . CI = 0.33, RI = 0.33.
The hypothesis that the Oniticellini and Onthophagini constitute a monophyletic group is strongly supported by this study (Figs
Biogeographical analysis using S-DIVA of the Oniticellini and Onthophagini showing relative probabilities of ancestral area alternative distributions. Each color and associated letter code represents a biogeographic area used in the analysis: A Afrotropical B Palaearctic C Oriental D Australasian E Madagascar F Nearctic G Neotropical H Caribbean. Font in bold indicates Onthophagini taxa.
The tribe Onthophagini is monophyletic in all analyses. For the Oniticellini two results were discovered. The tribe is monophyletic in the Bayesian tree (Fig.
K values of 8–10 also resulted in identical topologies (Fig.
In all analyses, the Helictopleurina and Drepanocerina are monophyletic (supported by four and six controverted synapomorphies respectively) while the Oniticellina is paraphyletic. The sister relationships of Tiniocellus + Scaptocnemis, Tragiscus + Oniticellus, and Anoplodrepanus + Euoniticellus are also invariant in all analyses. Attavicinus monstrosus (Bates), formerly placed in Liatongus (see
This tribe is a well-defined monophyletic group based on both Bayesian and parsimony analyses, and using either unweighted or weighted data. In the unweighted topology, five states (one uncontroverted) support monophyly. The relationships found with K values = 8–10 are identical (Fig.
The trees found with the most extreme weighting (K values of 1–3) compared to all others are the most different (Fig.
The probable symphile taxa (from Amietina to the tree apex) with the most derived features have strong support for monophyly; all included nodes are supported by a minimum of one uncontroverted and two controverted states. These lineages are not dung feeders but necrophilous (Amietina), myrmecophilous (Haroldius, Megaponerophilus, Alloscelus, and likely Eusaproecius and Pseudosaproecius) or termitophilous (Heteroclitopus, Pinacotasus, Stiptopodius, and probably Sukelus). Inquiliny most parsimoniously evolved only once in the common ancestor of Haroldius through to Sukelus. Support for this clade is based on five character states, including one uncontroverted. The Alloscelina (Alloscelus, Haroldius, and Megaponerophilus) is found within this larger clade but there is no support for its monophyly in any of the tree searches performed.
These results and the morphological studies of
In contrast to all other studies,
Traditionally the Oniticellini are divided into three subtribes, the Drepanocerina, Helictopleurina, and the Oniticellina (e.g.,
The Drepanocerina currently contain 12 genera but until recently included only two, Cyptochirus and Drepanocerus. Even the genus Cyptochirus was previously considered a synonym of Drepanocerus (e.g.,
The two representatives in this study, Cyptochirus and Afrodrepanus, were found as sister taxa. The Drepanocerina may not be monophyletic based on preliminary studies mentioned but not discussed in
The Madagascar endemic helictopleurines are composed of only two genera, the speciose Helictopleurus with ~80 species and the monotypic Heterosyphus. The included species of Helictopleurus representing three subgenera are strongly supported as monophyletic. The rare Heterosyphus was not available for study. When
The position of the Helictopleurina in the moderately or heavily weighted topologies supports the recognition of the group as either a monophyletic subtribe or tribe. In contrast, the unweighted or slightly weighted topologies support the creation of a new tribe to avoid a paraphyletic Oniticellini. But molecular evidence from
The subtribe Oniticellina is paraphyletic, although some generic sister relationships are invariant (see in results above). Euoniticellus and Paroniticellus have been classified as subgenera of Oniticellus in the past (
While an African Euoniticellus was included in this study, the single New World species E. cubiensis Laporte from the West Indies (Cuba, Jamaica, Isla de la Juventud, and the Bahamas (
Several genera not included also deserve brief comments. The monotypic genus Scaptodera was removed from generic synonymy by
Based on this study, a solution for monophyly within the Oniticellini subtribes outside of the Helictopleurina would be to recognize all genera (including the Drepanocerina) in a single subtribe, or alternatively, the recognition of the Drepanocerina and two or more subtribes. From the Bayesian analysis and the majority of parsimony topologies found (see Figs
Drepanocerina: Afrodrepanus, Clypeodrepanus, Cyptochirus, Drepanocerus, Drepanoplatynus, Eodrepanus, Epidrepanus, Ixodina, Latodrepanus, Paraixodina, Sinodrepanus and Tibiodrepanus.
Helictopleurina: Helictopleurus (with Heterosyphus a junior synonym of Helictopleurus).
Liatongina subtr. n. Philips. Type genus Liatongus Reitter, 1893: Liatongus Reitter (monophyly of the genus needs confirmation).
Diagnosis: This subtribe can be characterized by the following two characters: The mesonotal prescutum anteriorly with the transverse plate approximately ventrally directed is narrowly rounded apically and the posterior median tormal process (epitorma) of the epipharynx is smoothly and broadly tapered throughout its length. Based on a weighted topology (K=3) the three following characters also support this clade: The prothoracic apodeme has an incomplete oblique suture/carina, one or more “extra” internal sclerites are associated with the galea, and the metanotum scutellum posteriorly has a slight margin or remnant edge.
Oniticellina: Anoplodrepanus, Euoniticellus, Nitiocellus, Oniticellus, ScaptocnemisScaptodera, Tiniocellus, Tragiscus and Yvescambefortius.
Attavicina subtr. n. Philips. Type genus Attavincinus Philips & Bell, 2008: Attavicinus and Paroniticellus.
Diagnosis: This subtribe can be characterized by the following combination of characters: Maxilla internal accessory sclerite is curved near the proximal apex, the protibia on the proximal side has a line of setae associated with a carina, males have a longitudinal ridge on the pronotum laterally, and the mesosternal scutum is distinctly transverse in shape.
Note that based on the most heavily weighted parsimony topologies (Piwe K values = 1 and 2), Paroniticellus should be placed within the Oniticellina. Based on the Bayesian topology, Paroniticellus may need to be placed in its own or possibly one of the other subtribes, as its relationship to the other subtribes (excluding the Helictopleurina) is unclear.
This tribe in every analysis was a well supported monophyletic group.
The topologies found herein with extreme weighting K = 1–3 topologies are considered less trustworthy compared to those found with higher K values. This conclusion is also supported by the molecular studies of
As a very preliminary test of monophyly for Onthophagus, three species were studied, including one Nearctic, an Australian, and one Ethiopian. Also included were four taxa that are usually considered subgenera of Onthophagus (i.e., Digitonthophagus, Diastellopalpus, Proagoderus, and Strandius), as well as Euonthophagus, Hyalonthophagus, and Mimonthophagus. All will be considered Onthophagus, sensu lato in the discussion below.
In this study, Onthophagus, in either the strict or broad sense, is not monophyletic. Onthophagus, sensu stricto, typically appears in three clades. Onthophagus, sensu lato, appear in various topologies in no fewer than four to as many as nine separate lineages. Strandius often appears as part of a clade of Onthophagus while Euonthophagus, Hyalonthophagus and Mimonthophagus are justified as genera evolutionarily distinct from Onthophagus. In regards to Onthophagus, sensu stricto, molecular evidence from
Two phylogenetic studies have been done that concentrate mainly on Onthophagus. One on the “Serrophorus” complex (
From various sources (Wikispecies website accessed 3 N. 2015, Zunino 1979, Lumaret and Kim 1989,
There are a number of scarabaeine species that historically have been placed in various tribes, reflecting difficulty in their classification. This often included some of the inquilinous scarabaeines with highly modified morphologies, such as flattened leg segments and the presence of trichomes (e.g.,
Two problematic genera are Haroldius Bocomont and Cassolus Sharp.
In
Ancestral oniticellines and onthophagines are presumed to have been coprophagous as all of the basal lineages are dung feeders. Tunneling behavior in this clade is very similar amongst taxa and all are classified as Pattern I nesters in
Both tribes are characterized typically and most distinctively by the absence of a brood ball and larvae are supplied with a brood mass that is either modified to some degree or not. Additionally, male-female cooperation is absent or limited and brood care is not known to exist. These are simple behaviors in what one could argue is a derived lineage compared to some of the more ancient origin tunneling clades where complex behaviors evolved. For example, coprines construct brood ovoids, and have extensive male-female cooperation, and brood care. But simple nesting behavior appears to be a very successful strategy evolutionary; the oniticellines and onthophagines are some of the most successful dung beetles in many ecosystems in terms of number of species, and often in terms of abundance and biomass (
The African endemic Stiptopodius and Pinacotarsus groups of onthophagines form a monophyletic clade as discussed above. Based on the results, all included species are probably either myrmecophilous or termitophilous. As evidenced by the relatively high diversity within this lineage, the association with social insects may be relatively ancient. In contrast, only the New World oniticelline, Attavicinus montrosus, is an inquiline. This species is associated with leaf-cutter ant debris piles and has a very restricted distribution in central Mexico (
Above these clades (in less derived positions) in successive steps are three additional lineages also associated with social insects. The first, Alloscelus, is thought to be closely related to Pseudosaproecius (due to similar male genitalia and form of sexual dimorphism) but they do not form a monophyletic clade. The second and third, Megaponerophilus and Haroldius + Cassolus, are mainly myrmecophiles, with the exception of Cassolus where only one species of nine is known to be an ant associate (
In summary, the evidence in this analysis suggests that there may be a single origin of inquiliny in the onthophagines. Several genera with unknown habits are probably associated with either ants (Eusaproecius and Pseudosaproecius) or termites (Sukelus). The other four genera may also be considered as part of this clade although future studies may shift Haroldius and Cassolus out of the onthophagines. The evolution of myrmecophily preadapting the more derived taxa for an association with the Isoptera also seems plausible.
Necrophagy and mycetophagy are rare within the oniticellines and onthophagines and perhaps are recently evolved behaviors with several independent origins. For example, Liatongus rhinocerulus (
The Oniticellini and Onthophagini are postulated to be a relatively modern aged group of dung beetles by
Another general trend of the Oniticellini appears to be successive invasions from the Ethiopian into the Palaearctic through to the Oriental region (including the Lesser Sunda Islands and Sulawesi) in many groups (e.g., Tibiodrepanus (
Based on basal branching, the oniticelline ancestors that led to the Madagascan helicopleurines, the Palaearctic Paroniticellus, and the New World Attavicinus and Liatongus may be relatively old dispersal events. Dispersal of an ancestral oniticelline from Africa to Madagascar during the early to middle Cenozoic may be the most likely hypothesis for the presence of the helictopleurines (see
The New World oniticellines belonging to Attavicinus and Liatongus may each represent separate invasions by ancestral species from Asia to North America via Beringia. The land connection between these continents has been present from the mid-Cretaceous up through the late Pliocene 3.5 Mya and several more times during the Pleistocene (
The Mexican Attavicinus monstrosus generally appears as sister to Paroniticellus, a monotypic genus known from middle Asia and Turkey. This close relationship is difficult to explain compared to the latter’s alternate position in the K = 1 or 2 extreme weighted trees, where it is deep within a paraphyletic Oniticellina. But links between the eastern/western Palearctic with western Nearctic are certainly known (
The two Nearctic Liatongus species, L. californicus (Oregon and northern California) and L. rhinocerulus (northern and central Mexico) most likely share a most recent common ancestor based on very similar external morphologies and close but disjunct distributions. The one representative included in this study, L. californicus, nearly always appears as sister to a larger clade that has as its basal lineage an Old World species of Liatongus.
The Jamaican endemic Anoplodrepanus and an African representative of Euoniticellus appear as sister taxa in all topologies discovered. It is a relatively derived lineage appearing at the apex of the Oniticellini topology with its sister clade of Cyptochirus + Afrodrepanus. Euoniticellus has an African origin with Palaearctic and Asian species and a single New World member, E. cubiensis (Cambefort, 1996). A link between the faunas of Africa and the Caribbean has been reported elsewhere for many groups of insects and studies give both vicariance and dispersal hypotheses (e.g.,
Few biogeographic studies have been completed on individual genera. But in one on Eodrepanus (
The Onthophagini dispersal pattern is similar to that seen in the Oniticellini, but continued into Australia and South America, as well as everywhere else where one finds dung beetles. The African, Asian, and Palaearctic regions contain a total of 30, 11, and 3 genera, respectively. But of the total 35 Onthophagini genera, most are endemic to either the African (22 genera) or Asian (4 genera) regions (
Onthophagus alone is the most widespread as well as the most speciose genus, comprising at least 45% of the species of Scarabaeinae. It is also the only onthophagine genus that has spread outside of the Ethiopian, Oriental, or Palaearctic regions. Based on
This study is the first with a broad range of taxa from these two tribes that strongly supports the monophyly of the Oniticellini + Onthophagini, and the Onthophagini. The Oniticellini are also monophyletic in the Bayesian analysis (Fig.
In all topologies, the Helictopleurina are monophyletic. Recognition of this clade as a tribe would eliminate the potential paraphyly of the oniticellines in unweighted and weighted topologies (K = 11–30). But, since molecular data shows the helictopleurines as more derived oniticellines and not a basally originating lineage, the group should continue to be recognized as a subtribe. The Drepanocerina is supported as monophyletic. The Oniticellina is paraphyletic without the Drepanocerina and therefore redefinition of the former and the recognition of additional subtribes is needed if one desires to maintain monophyly in the classification.
The three most thorough molecular studies on the Oniticellini and Onthophagini generally support the monophyly of the two tribes combined and the Oniticellini (
Certainly larger molecular data sets and perhaps large numbers of morphological characters from a broad range of taxa is needed to help stabilize our conclusions and understanding of the evolution of these two major tribes of Scarabaeinae. Morphological phylogenies have the advantage that rarely collected taxa can be included. Regardless, future molecular studies using new techniques will produce large amounts of data and will clarify the evolution of these tribes and major clade divergence times (but see
I sincerely thank Tristão Branco (Porto, Portugal), D.W. Edmonds (Waco, Texas, USA), Bruce Gill (Agriculture Canada, Ottawa, Canada), Malcolm Kerley (Natural History Museum, London, United Kingdom), and Fernando Vaz-de-Mello (Universidade Federal de Mato Grosso, Cuiabá, Brazil) for their help in supplying many valuable specimens. Tristão Branco, Adrian Davis and Bruce Gill also helped with various discussions on the group. Preliminary work was supported via a postdoctoral fellowship at the University of Pretoria, South Africa with Clarke Scholtz. I also thank Richard Bowker, the Department of Biology, Ogden College, and Western Kentucky University for their support of this project and John Andersland for advice and assistance on figure design. Thanks also to Linda Gerofsky for assistance with editing. Adrian Davis, Frank Krell (editor), and two anonymus reviewers gave many useful comments on this manuscript. One in particular deserves special thanks for a very careful and detailed review. I am grateful to Robert Neidlinger who photographed and carefully edited most of the automontage images of the specimens illustrated in the trees. Lastly, thanks to Harry Taylor and Max Barclay (Natural History Museum, London) for arranging photography of the Sukelus and Cassolus specimens.