jueves, 28 de abril de 2011



RUTELINAE

Classification

Kingdom Animalia (Animals)

Phylum Arthropoda (Arthropods)

Class Insecta (Insects)

Order Coleoptera (Beetles)

Suborder Polyphaga (Water, Rove, Scarab, Longhorn, Leaf and Snout Beetles)

Superfamily Scarabaeoidea (Scarab, Stag and Bess Beetles)

Family Scarabaeidae (Scarab Beetles)

Subfamily Rutelinae (Shining Leaf Chafers)








Antes de comenzar necesitamos saber en donde estamos, para lo cual nos ayudaremos de Mary Liz Jameson, luego veremos lo que nos cuentan los expertos y terminaremos con 2 regalos (una pequeña explicación a los diferentes patrones de color y algunas claves)



Mary Liz Jameson and Brett C. Ratcliffe

Scarabeiformia (crowson, 1960)
Scarabaeoidea (latreille, 1802)


The superfamily Scarabaeoidea is a large, diverse, cosmopolitan group of beetles. Scarabaeoids are adapted to most habitats, and they are fungivores, herbivores, necrophages, coprophages, saprophages, and some are carnivores. They are widely distributed, even living in the Arctic in animal burrows. Some scarabs exhibit parental care and sociality. Some are myrmecophilous, termitophilous, or ectoparasitic. Many possess extravagant horns, others are able to roll into a compact ball, and still others are highly armored for inquiline life. Some are agricultural pests that may destroy crops while others are used in the biological control of dung and dung flies. Scarabaeoids are popular beetles due to their large size, bright colors, and interesting natural histories. Early Egyptians revered the scarab as a god, Jean Henri Fabre studied their behavior, and Charles Darwin used observations of scarabs in his theory of sexual selection.


A continuación se pretende presentar una visión general de la Subfamilia Rutelinae teniendo en cuenta diferentes perspectivas


  1. Mary Liz Jameson (AMERICAN BEETLES VOLUME 2, 2002)
  2. Alan Hardy (A CATALOG OF THE COLEOPTERA OF AMERICA NORTH OF MEXICO)
  3. Käfer (1985)
  4. German Amat Garcia (GUIA PARA LA CRIA DE ESCARABAJOS, COLOMBIA, 2005)
  5. M. A. Morón (Instituto Nacional de Biodiversidad, COSTA RICA)
  6. Angel Solís (Instituto Nacional de Biodiversidad, COSTA RICA)
  7. Univarsity of Nebraska State Museum
  8. JONATHAN BROWNE CLARKE H. SCHOLTZ (1999)



  • MARY LIZ JAMESON


RUTELINAE MACLEAY 1819
Common name: The shining leaf chafers

Characteristics:
Form elongate oval. Labrum produced weakly beyond apex of clypeus (except in Anomalacra [Anomalini]). Antenna with 8-10 segments, antennal club with 3 segments. Anterior coxae transverse. Scutellum exposed. Tarsal claws on all legs independently movable, claws unequal in length or size and frequently weakly split at apex, 1 claw of each pair greatly reduced (1 claw lacking on all legs in Leptohoplia [Anomalini]). Onychium laterally flattened. Pygidium exposed beyond apices of elytra.
The subfamily Rutelinae is composed of approximately 200 genera and 4,100 species that are distributed worldwide (Machatschke 1972), although many taxa remain to be describe Adult rutelines are phytophagous and feed on leaves, flowers, or flower parts. Larvae feed on roots, compost, and decaying vegetation. Some taxa, such as Popillia japonica Newman and Anomala species (both Anomalini), are agricultural pests. The common name of the subfamily, the shining leaf chafers, reflects the fact that many members of the subfamily are brightly colored, beautifully patterned, and often brilliantly metallic leaf-feeding beetles. Others in the subfamily, such as the genus Anomala, are small, obscure beetles. The subfamily is divided into six tribes, two of which occur in the United States. The tribe Spodochlamyini is found only in Central and South America; the tribe Anoplognathini occurs in the Australia and Central and South America; the tribe Adoretini is distributed throughout the Old World; the tribe Geniatini is distributed in Central and South America. The two remaining tribes, Rutelini and Anomalini, are the most speciose ruteline tribes and both occur in the Nearctic region. The tribe Rutelini is widely distributed but is most speciose in the Neotropics. The tribe Anomalini is widely distributed and is most speciose in the Old World. In the Nearctic region, the subfamily includes 14 genera and 95 species. Keys to genera and species: Casey 1915; Cooper 1983; Jameson 1990, 1998. Keys to larvae: Ritcher 1966; Jameson et al. 1994, Jameson 1998. United States catalog: Hardy 1991; Smith 2001. Regional works: Blatchley 1910; Loding 1945; Saylor 1948b; Edwards 1949; Hatch 1971; Kirk and Balsbaugh 1975; Lago et al. 1979; Ratcliffe 1991; Downie and Arnett 1996; Morón et al. 1997; Harpootlian 2001. World catalog: Machatschke 1972.



  • ALAN HARDY


The Rutelinae and Dynastinae are large, diverse groups found on every continent or major land mass in the temperate and tropical zones.
Rutelinae larvae are root feeders, many of grass or grass crops, and may be of economic concern. Adults are foliage feeders or may be nonfeeding. There are diurnal, nocturnal, and crepuscular behavior patterns, and many species are attracted to lights. Anomalini generally are nocturnal or crepuscular, spending the day buried in the soil, and are most readily taken at light. Rutelini are often diurnal, although some groups are strictly nocturnal. Diurnal representatives usually spend the night on the host plant, whereas nocturnal groups may pass the day on the host plant or in the soil. Rutelini often are spectacularly colorful.
The Rutelinae and Dynastinae are subject to population fluctuations that may result in local explosions of individuals. Major parasites of these groups include Hymenoptera (Tiphiidae, Scoliidae, Ichneumonidae, Braconidae), Diptera (Tachinidae, Sarcophagidae), Acarina, (Pyemotidae and Tyroglyphidae), and the Acanthocephala (thorn- or spiny-head worms).



  • KÄFER (1985)


Unterfamilie Rutelinae
Scarabaeoidea-Scarabaeidae-rutelinae

Gedrungene, 8-22 mm lange Arten, braun, schwarz und metallfarben. Fühler 9gliedrig, Fächer 3gliedrig. Schildchen gut sichtbar, hinten abgerundet. Die Flügeldecken lassen das Pygidium und einen Teil des vorletzten Tergits frei. Außenseite der Vorderschienen mit 2-3 Zähnen; Füße mit ungleichen Klauen. Bei allen Männchen Innendorn der Vorderschienen in Höhe des vorletzten Außenzahnes, bei den Weibchen nach vorn verschoben. Vorderfußglieder der Männchen bei einigen Arten verbreitert. In Hainen, Wäldern, Baumgärten, auf Wiesen; fliegen tags und abends. Die Eier werden mit Vorliebe in Sandboden gelegt; die Larven leben an Wurzeln. Anomala dubia (Scopoli, 1763) Metallischer Julikäfer 21 Synonym: Anomala aenea De Geer

BESCHREIBUNG: Gedrungen, gewölbt, Färbung ziemlich variabel, am häufigsten metallgrün, Halsschildrand, Flügeldecken, Beine und Fühler gelb bis braun. Kopf, Halsschild und Schildchen dicht punktiert, Halsschild vorn gerandet, hinten ungerandet. Flügeldecken mit 10 gepunkteten Streifen, Schulterbeule stark entwickelt.
VARIABILITÄT: Im Norden hellere, im Süden dunklere Formen. Es gibt Tiere, bei denen die gelbe Farbe auf Halsschild und Pygidium überwiegt.
ERSCHEINUNGSZEIT: Käfer fliegen von Mai bis August an sonnigen Tagen und abends.

VORKOMMEN: Auf Sand- und Sandlehmböden mit Weiden, Birken, Pappeln, Ulmen, Haselsträuchern u. a.
VERBREITUNG: Europa von Süditalien bis Südnorwegen, Mittelschweden und -finnland; lokal in England und Schottland. Phyllopertha horticola (L., 1758) Juni-, Gartenlaubkäfer 21
BESCHREIBUNG: Stark metallisch grün bis schwarz glänzend, Flügeldecken hell- bis orangebraun, mitunter dunkler. Naht und Seitenränder der Flügeldecken dunkel. Seiten, Unterseite und Beine hell behaart. – Kopf vorn dichter punktiert als auf dem Scheitel. Halsschild vor allem vorn breit gerandet, punktiert; seitlich vor der Basis leicht ausgeschnitten, so daß die Hinterecken rechtwinklig sind. Flügeldecken mit je 6 Punktlängsstreifen.
BIOLOGIE: Larve im Erdboden an Würzelchen, Käfer am Laub von Eichen, Hasel, Birken und Blüten, vor allem von Rosen und Kirschen. Stellenweise früher als Schädling betrachtet, heute ohne nennenswerte wirtschaftliche Bedeutung.

ERSCHEINUNGSZEIT: Käfer im Mai und Juni, Entwicklung 2-3 Jahre.
VORKOMMEN: Gärten, Wiesen und Waldränder von der Tiefebene bis ins Gebirge.
VERBREITUNG: Eurasien: im Norden bis Mittelfennoskandien; Britische Inseln; Gebirge in Südeuropa.



  • GERMAN AMAT GARCIA


los escarabajos fitófagos, incluidos en la familia MELOLONTHIDAE. En este grupo se encuentran los escarabajos plateados o de la subfamilia Rutelinae, los escarabajos frugívoros o de la subfamilia Cetoniinae y los escarabajos cornudos o de la subfamilia Dynastinae.
Los rutelinos o escarabajos plateados, varían en tamaño entre los 3 y 60 mm. Generalmente tienen forma ovalada, redondeada y convexa. Sus patas son cortas y un poco robustas. Las uñas de cada pata tienen diferente longitud y grosor y en algunos casos muestran sus extremos bífidos o presentan un dientecillo en el borde medio inferior.
Estas uñas pueden cerrarse como verdaderos broches de presión sobre los bordes de las hojas en las cuales permanecen alimentándose. Los machos se distinguen de las hembras por la forma del abdomen y en ciertos grupos por la longitud y el grosor de las patas posteriores. Su coloración abarca desde el negro intenso brillante hasta el plateado, pasando por casi todos los colores y combinaciones, incluyendo el blanco puro.
Las larvas se desarrollan en troncos derribados, en los suelos ricos en materia orgánica y algunas pueden ser rizófagas. Los adultos de este grupo también han sido registrados como plagas del follaje y de las flores de algunas plantas con importancia agrícola u ornamental.
Es posible encontrarlas en casi todos los ecosistemas establecidos entre el nivel del mar y los 2500 m. Los adultos tienen hábitos diurnos, crepusculares o nocturnos. Sus ciclos vitales duran entre uno y dos años.
El grupo de los escarabajos fitófagos (Melolonthidae) está ampliamente diversificado en el país pues se conocen 107 géneros y 582 especies (Restrepo et. al, 2003). De este gran grupo se conocen 36 géneros y 203 especies de escarabajos plateados o rutelinos, entre los que se destacan especies pertenecientes a los géneros Plusiotis, Rutela, Chlorota, que exhiben coloraciones dorada, plateada, verde brillante, con azul, púrpura, rosado o amarillo.



  • MIGUEL ANGEL MORÓN


Los rutélinos varían en tamaño entre los 3 y 60 mm. Generalmente tienen forma ovalada, redondeada y convexa. Sus patas son cortas y un poco robustas. Las uñas de cada pata tienen diferente longitud y grosor y en algunos casos muestran sus extremos bífidos, o presentan un dientecillo en el borde medio inferior. Estas uñas pueden cerrarse como verdaderos broches de presión sobre los bordes de las hojas, en las cuales permanecen alimentándose. Los machos se distinguen de las hembras por la forma del abdomen, y en ciertos grupos por la longitud y el grosor de las patas posteriores. Su coloración abarca desde el negro intenso brillante hasta el plateado, pasando por casi todos los colores y combinaciones, incluyendo el blanco puro. En Costa Rica son famosas las especies del género Plusiotis, que exhiben coloraciones doradas, plateadas, verdes brillantes, con azul, púrpura, rosado o amarillo. En Costa Rica se han citado cerca de 15 géneros y 70 especies de esta subfamilia, y se considera que aún quedan muchas especies por registrar o describir como nuevas para la ciencia.
Las larvas se desarrollan en troncos derribados, en los suelos ricos en materia orgánica, y las de algunas especies, como las del género Anomala, consumen raíces. Los adultos de este grupo también han sido registrados como plagas del follaje y de las flores de algunas plantas con importancia agrícola u ornamental. Es posible encontrarlas en casi todos los ecosistemas establecidos entre el nivel del mar y los 2500 m. Los adultos tienen hábitos diurnos, crepusculares o nocturnos. Sus ciclos vitales duran entre uno y dos años.



  • ANGEL SOLÍS


Entre los Scarabaeoidea, ésta subfamilia es la que a la mayoría de las personas más llama la atención, lo anterior debido a lo atractivo de la coloración de muchas de sus especies. Dentro de ella se encuentran los muy apreciados escarabajos dorados, verdes y plateados de género Chrysina (antes Plusiotis).
Su cuerpo es normalmente convexo dorsalmente sin cuernos ni protuberancias en la cabeza o el tórax, aunque en muchas especies el tubérculo meso-metaesternal está muy desarrollado. Las uñas tarsales pueden ser bífidas o enteras, pero siempre, en cada pata, una de cada par es algo mayor que la otra. En general las hembras poseen la porción distal de las tibias posteriores más anchas que las de los machos, mientras que en los machos por su parte los tarsos anteriores son más robustos que en las hembras.
Muchas especies de este grupo son nocturnas, existiendo no obstante una buena parte de ellas de hábitos diurnos. Cuando adultos, se alimentan de follaje de ciertas plantas, flores y algunos de frutos suaves. Las larvas se alimentan principalmente de troncos podridos de árboles o menos frecuentemente de materia orgánica o raíces en el suelo.
En Costa Rica existen no menos de 220 especies en 34 géneros diferentes.





  • UNIVERSITY OF NEBRASKA STATE MUSEUM

http://www.unl.edu/museum/research/entomology/Guide/Scarabaeoidea/Scarabaeidae/Rutelinae/Rutelinae-Overview/RutelinaeO.html

Shining leaf chafers

Characteristics

Form elongate oval. Labrum produced weakly beyond apex of clypeus (except in Anomalacra [Anomalini]). Antenna with 9 or 10 segments, antennal club with 3 segments. Scutellum exposed. Anterior coxae transverse. Mesotibial apex with 2 spurs; spurs mesad, adjacent (not separated by basal metatarsal segment). Tarsal claws on all legs independently movable, claws unequal in length or size and frequently weakly split at apex, 1 claw of each pair greatly reduced (1 claw lacking on all legs in Leptohoplia [Anomalini]). Onychium laterally flattened. Pygidium exposed beyond apices of elytra. References: Ohaus 1934, Machatschke 1957, Machatschke 1965.

Classification Status

MacLeay (1819) proposed the family Rutelidae for taxa previously included in the genus Scarabaeus Linneaus. Since Blanchard (1851) the group has been referred to as a subfamily of Scarabaeidae. Some workers regard the group as a family or as a subfamily of Melolonthidae. We follow Machatschke (1972) and Lawrence and Newton (1995) and regard the Rutelinae as a subfamily of the Scarabaeidae. Tribal classification of the subfamily is stable, but some tribes may be paraphyletic (i.e., Rutelini [see Jameson 1998]). The ruteline tribe Anomalini is occasionally regarded as a subfamily of Scarabaeidae (i.e., Potts 1974, 1977a, 1977b) or a subfamily of Melolonthidae (i.e., Sabatinelli 1991). In addition, Hoplia and its congeners have occasionally been included as a tribe (Hopliini) and included the Rutelinae (i.e., Baraud 1985). Subtribal classification of the subfamily is, in many cases, based on diverse assemblages of taxa, and many subtribes are not monophyletic. Phylogenies for the Scarabaeoidea hypothesize three differing views for the relationship of the Rutelinae: 1) that the subfamily Dynastinae is ancestral to the Rutelinae, 2) that the Dynastinae and Rutelinae are sister groups, or 3) that the subfamilies are possible sister groups and that their relationships remain unresolved (Endrödi 1966; Howden 1982; Iablokoff-Khnzorian 1977; Meinecke 1975; Scholtz and Chown 1995).

Distribution

The subfamily Rutelinae is composed of approximately 200 genera and 4,100 species that are distributed worldwide (Machatschke 1972), although many taxa remain to be described. The subfamily is divided into six tribes, five of which occur in the New World.
The tribe Spodochlamyini is found only in Central and South America; the tribe Anoplognathini occurs in the Australia and western Central and South America; the tribe Geniatini is distributed in Central and South America; the tribe Rutelini is widely distributed but is most speciose in the Neotropics; the tribe Anomalini is widely distributed and is most speciose in the Old World. The tribe Adoretini is exclusively distributed in the Old World. In the New World, the subfamily includes about 95 genera. Keys to genera and species: Casey 1915; Cooper 1983; Jameson 1990, 1997. Keys to larvae: Ritcher 1966; Jameson et al. 1994, Jameson 1997. United States catalog: Hardy 1991. Mexico, Central and South America catalog: Blackwelder 1944. World catalog: Machatschke 1972.

Ecology

Adult rutelines are phytophagous and feed on leaves, flowers, or flower parts. Larvae feed on roots, compost, and decaying vegetation. Some taxa, such as Popillia japonica Newman and Anomala species (both Anomalini), are agricultural pests. The common name of the subfamily, the shining leaf chafers, reflects the fact that many members of the subfamily are brightly colored, beautifully patterned, and often brilliantly metallic leaf-feeding beetles. Others in the subfamily, such as the genus Anomala, are small, obscure beetles. Adults may aid in pollination of plants.

Larvae

Despite the potential agricultural importance of some rutelines, few ruteline larvae have been described. Larvae typically feed on decaying wood, compost, or roots. Ritcher (1966) characterized the North American ruteline larvae as follows: Mandibles with stridulatory area consisting of transverse ridges. Maxilla with row of anteriorly directed, sharp, pointed, stridulatory teeth; lacinia with 1-3 unci. Epipharynx with haptomerum, with or without plegmata, without proplegmata, two nesia usually present; haptomerum with two or more prominent heli (beak-like or mound-like) and with 15 or more prominent spine-like setae. Dorsal surface of abdominal segments 9 and 10 never fused. Raster with or without palidia; anal slit transverse, slightly curved. Claws each bearing 2 setae. Keys to genera: Jameson et al. 1994.

New World Tribes

Anomalini

Anoplognathini

Geniatini

Rutelini

Spodochlamyini


TRIBE ANOMALINI

Characteristics: Labrum horizontally produced with respect to the clypeus. Antennae with 9 segments. Protibiae bidentate (rarely unidentate or tridentate), inner protibial spur subapical (lacking in Leptohoplia); foretarsomeres not enlarged or densely setose ventrally. Elytra with membranous border at lateral margin. Terminal spiracle not positioned in pleural suture.

The tribe Anomalini includes one of the largest genera in the Animal Kingdom: the genus Anomala, which includes approximately 1,000 species worldwide. Adult anomalines feed primarily on flowers and floral parts. Larvae feed primarily on plant roots. One introduced member of the tribe, Popillia japonica Newman, causes economic damage to agricultural crops and ornamental plants. Despite the agricultural importance of some members, the tribe is poorly known taxonomically and in desperate need of revisionary studies. The tribe includes 11 genera in the New World. Keys: Cooper 1983; Potts 1974, 1977a, 1977b. Key to larvae: Ritcher 1966.

TRIBE ANOPLOGNATHINI

Characteristics: Labrum vertically produced with respect to the clypeus, with apicomedial projection. Mentum lacking apical tooth or projection. Antennae with 9 or 10 segments. Terminal spiracle positioned in pleural suture.

The tribe Anoplognathini is distributed in the southern hemisphere. Members are found in Australia (some members are commonly called Christmas beetles) and from central Mexico to southern South America. In the New World, the tribe includes five genera (Aulacopalpus, Brachysternus, Hylamorpha, Phalangogonia, and Platycoelia). Keys: Smith 2003.

TRIBE GENIATINI

Characteristics: Labrum vertically produced with respect to the clypeus, with apicomedial projection. Antennae with 10 segments. Protibiae tridentate, inner protibial spur apical; foretarsomeres usually enlarged in males and/or females and densely setose ventrally. Elytral margin chitinous or membranous. Terminal spiracle positioned in pleural suture.

The tribe Geniatini is exclusively a Neotropical group of beetles. Little is known of the natural history of the group. Members inhabit deciduous forests and cloud forests, and some adults are attracted to lights at night. In the new World, the tribe includes about 12 poorly studied genera. Keys: Machatschke 1965; Villatoro and Jameson 2001; Jameson and Hawkins 2005.

TRIBE RUTELINI

Characteristics: Labrum horizontally produced with respect to the clypeus. Antennae with 10 segments (8 or 9 in Parachrysina). Protibiae tridentate, inner protibial spur apical; foretarsomeres not enlarged or densely setose ventrally. Elytral margin entirely chitinous. Terminal spiracle positioned in pleural suture.

The tribe Rutelini is distributed worldwide but is most speciose in the Neotropics. A wide array of morphological forms is exhibited by members of the tribe including taxa with enlarged, horn-like mandibles (Fruhstorferia from Asia), backward-projecting thoracic horns (Peperonota from Asia), enlarged hind femora (Heterosternus and Chrysina from the New World), and strikingly-colored, metallic silver and gold beetles (Plusiotis from the New World). Exemplar genera in the tribe include Pelidnota, Macraspis (both of which are most diverse in Central and South America), and Parastasia (most diverse in the Old World with one species in the New World). The tribe includes over 70 genera in the New World. Keys: Cooper 1983; Jameson 1990; Jameson in prep. Keys to larvae: Ritcher 1966; Jameson et al. 1994; Jameson 1997. Catalog to Pelidnota and related genera.

Overview to Heterosternina.

TRIBE SPODOCHLAMYINI

Characteristics: Labrum vertically produced with respect to the clypeus, lacking apicomedial projection. Antennae with 10 segments. Protibiae tridentate, inner protibial spur apical; foretarsomeres not enlarged or densely setose ventrally. Elytral margin entirely chitinous. Terminal spiracle positioned in pleural suture.

The tribe Spodochlamyini is a small, Neotropical group that includes four genera. Members of the group are distributed primarily in cloud forest habitats in northernern South America. Adults are attracted to lights at night. Keys: Machatschke 1965.



JONATHAN BROWNE and CLARKE H. SCHOLTZ

Evolution of the scarab hindwing articulation and wing base: a contribution toward the phylogeny of the Scarabaeidae (Scarabaeoidea: Coleoptera)

(abstract + phylogeny)


Abstract. A study is made of the articulation and base of hindwings of Scarabaeidae. The survey is based on an examination of over 150 genera from sixteen scarabaeid subfamilies and taxa of uncertain phylogenetic status. Relationships among all subfamilies of Scarabaeidae are examined here for the first time. The constructed phylogeny shows that the scarabaeid lineage (Scarabaeidae) is comprised of two major lines: an aphodiine line (containing Aphodiinae, including Aegialiini, Aulonocnemis and Scarabaeinae), and an orphnine line (containing Orphninae, Melolonthinae, Acoma, Chnaunanthus, Hopliini, Oncerus, Rutelinae, Dynastinae, Trichiinae, Cetoniinae, Osmoderma and Valginae).




Fig. 2. Hypothesized branching patterns among members of Scarabaeidae based on ninety-three characters of the hindwing articulation and wing base (see Material and methods and Table 1). The tree shown here is the consensus tree of the two alternative trees produced by phylogenetic analysis; the first with the same topology as shown here, and the second with Orphninae as the sister group of the melolonthine subgroup, indicated by the dotted line. Solid boxes represent apotypic character states. Large numbers refer to branch points and smaller numbers refer to characters given in text (see Results and discussion). Characters which unite the Scarabaeidae (*) are given in Browne & Scholtz (1995).


¿¿¿POR QUE BRILLAN TANTO LOS RUTELINOS???

J. DAVID PYE, 2010

The distribution of circularly polarized light reflection

http://onlinelibrary.wiley.com/doi/10.1111/j.1095-8312.2010.01449.x/abstract


Abstract

The light reflected from many scarab beetles is strongly circularly polarized, a phenomenon that may be unique in nature. Approximately 1500 genera and more than 19 000 species/subspecies of scarab beetles (Scarabaeoidea) in the collection of the Natural History Museum, London, were surveyed with circularly polarizing filters to assess how widespread this effect is and how it relates to colour patterns in the individuals concerned. Over 1100 measurements were made of the strength of the circular polarization, in some cases registering 97%. Circular polarization had been previously described from five subfamilies of Scarabaeidae and, in the present study, was found in three further subfamilies: Phaenomeridinae, Dynastinae and Euchirinae, as well as in the subfamily Ceratocanthinae of the family Hybosoridae, comprising the first records outside the Scarabaeidae. The results may have implications for the taxonomy of the group, for visual discrimination, and for the behaviour of the species themselves.


The rutelines include many spectacular beetles. They are often large and brilliantly coloured, with metallic gold or silver, shiny or matt green, generally produced by structural means, and commonly associated with very strong CPR. Indeed, the rutelines stand alongside the cetoniines as leading exemplars of this property. Chrysina were remarkably consistent in that all 35 species in the collection showed strong CPR. It is not possible, however, to predict the presence of CPR by eye, without the help of polarizing filters (a circular polariscope), because the same colours may exist independently of CPR. Circular polarized reflection was first discovered in the ruteline C. resplendens (Michelson, 1911). However, this ‘brassy’ species is not one of the strongest examples as already noted by Kattawar (1994). Present observation of the 20 specimens available, shows a great deal of individual variation, with six specimens ranging to an exceptionally high a= 7.1, 75%. Some specimens, uniquely within this survey, showed reversed handedness: the ratio a was less than one, decreasing as low as a= 0.8, 11% righthanded in one specimen. This individual was judged by eye and a polariscope to be the most extreme of the reversed polarizations present (see below for further discussion).

By contrast, eight specimens of the spectacularly golden C. aurigans all showed very strong (lefthanded) polarization ranging up to a= 24, 92% and the brown-silvery Chrysina optima showed a maximum of a= 23, 92%, comparable with the strongest of cetoniines. It is curious that the strongest cetoniines were in the genus Chalcothea, whereas, in the rutelines, the shiny, dark green Chrysina chalcothea registered up to a= 14, 87% (presumably the green colour in each case is reminiscent of copper ores). Several other green species, including pale matt green ones, were classified as ‘strong’ (i.e. a > 2.0, 33%). Extremely high values were also found in the greenish-gold Anoplognathus parvulus at a= 25,92%, and Anoplognathus aureus gave a= 20, 90%. However, the shiny green pronotum of Anoplognathus daemeli gave a= 5.4, 69% with the elytra at only a= 1.8, 29% and Anoplognathus brunnipennis gave a= 4.9, 69% but only a= 1.1, 5% on the elytra. Other high values were found in Anomala rosette (a= 10, 82%), Anomala pterygophorus (a= 12, 85%), Microrutela campa (a= 13, 86% in a green specimen), Chrysophora chrysochlora (a= 10, 82%), and Anoplognathus lamprimoides (a= 9.2, 80). The very large genus Adoretus, sometimes regarded as a tribe within the Rutelinae, was represented by 226 species, of which 211 showed no CPR. The remainder were mostly weak, with the highest being Adoretus aenescens (maximum: a= 3.3, 53%), Adoretus sikorae (a= 2.0, 33%), and Adoretus vagepunctatus (a= 1.7, 26%).

Michelson (1911) found that in his specimen of C. resplendens the circular polarization was strongest for blue light, diminished in yellow and was absent for orange–yellow, whereas red light appeared to be circularly polarized in the opposite (right-handed) sense. Gaubert (1924) confirmed that relationship in Chrysina amoena. However, Neville & Caveney (1969) considered that this might all be a mistaken impression due to the use of a polarizing filter that incorporated a retarder plate of 550 nm rather than the more usual 150 nm. This is difficult to understand: the correct quarter-wave or 150 nm retarder was readily available even to Victorian microscopists as a mica component and, together with a Nicol prism linear polarizer, it would make an excellent circular polarizer (or analysing filter) and was often thus used; by contrast, the other common retarder, the 550 nm or ‘full-wave’ type (then made of gypsum), cannot be used to make a circular polarizer and has quite different functions (Pye, 2001). Furthermore, Michelson was a world renowned optical physicist, having already received the Nobel prize for his share in the seminal Michelson–Morley experiment that disproved the presence of an all-pervading ‘aether’ and paved the way for relativity. He would have known exactly what he was doing.

Neville & Caveney (1969) reported that all the species they investigated reflected lefthand circularly polarized light ‘irrespective of the wavelength of the reflected colour’ (although this wording does not necessarily imply an absence of any spectral bias). Hegedus, Szel & Horvath (2006) investigated the problem with a non-quantitative photographic method in the rutelines Chrysina resplendens and Chrysina chrysochlora, as well as Proaetia speciosa (as Cetonischema jousselini)of the Cetoniinae. They found examples of right-handed polarization with certain colours but concluded that the situation is ‘complicated’. Goldstein (2006) found that in Chrysina resplendens ‘there are scarabs for which the hand of the circular polarization reverses from the blue end of the spectrum to the red’. Thus, to date, there is mixed support for Michelson’s observations, although they cannot be disputed because there appears to be considerable individual variation in this respect and his specimen could well have behaved as he described. Thus, although differences in colour responses are not central to this taxonomic survey, it appeared worthwhile to examine the subject briefly. A selection of various Chrysina species was examined carefully by eye with a circular polariscope as usual and then with the polariscope covered in turn by each of the three colour filters. There was no indication that handedness of polarization was reversed in red light and the effects appeared to be substantially similar to those with white light as described above. Two specimens of C. resplendens were chosen for repeated quantitative measurements under the Coleopticon but with the colour filters placed in turn over the LED-lamp aperture. The chosen specimens were one that showed the greatest value of left-handed polarization and the one that most clearly showed reversed (right-handed) polarization. The results are summarized in Table 4. It is clear that, in these two specimens at least, there was no consistent spectral trend.

In specimen A, the left-handed (normal) specimen, the red and green readings were the same as for white light, but blue light appeared not to contribute to the polarization. In specimen B, the aberrant righthanded specimen, both blue and green appeared to contribute nothing to the polarization, which was entirely a result of the red. In this case, red was indeed right-handed. The Coleopticon was also used to compare values of polarization in white, red and green light from a matt green Chrysina chrysopedila; the degree of polarization was virtually the same throughout. In Anomala jansoni, a green colour was overlain by a purplish sheen which disappeared under a right-circular filter to leave the green. Values were a= 2.0, 33% in both white and red light, and a= 1.0, 0% in green, as might have been expected. The problem of spectrally dependent handedness clearly deserves much more detailed study, although this would require a more elaborate apparatus than was available for this survey


CLAVES

KEYs

  • KEY TO THE TRIBES OF RUTELINAE

(modified from Ohaus 1934)

  • KEY TO THE SUBTRIBES OF RUTELINI

(modified from Ohaus 1934)

  • KEY TO THE GENERA OF AREODINA

  • KEY TO THE SPECIES OF VIRIDIMICUS

  • Key to the American Genera of Rutelini Based on Third-Instar Larvae

(Modified from Jameson 1999)

  • Clave para separar algunas de las larvas de tercer estadio de Melolonthidae comunes en los suelos de la región Altos de Chiapas, México.

Concepción RAMÍREZ-SALINAS, Miguel Ángel MORÓN2 y Adriana E. CASTRO-RAMÍREZ, (2004)

  • Key to the New World Genera of Anomalini

(after Jameson, Paucar-Cabrera, and Solıs 2003)

(Phyllopertha latitarsis Nonfried is incertae sedis and is omitted from the key)

(ingles y español)

  • Clave para los géneros de la tribu Anomalini del Nuevo Mundo

(Modifi cada de Morón y Nogueira, 1999; Jameson et al., 2003; Paucar-Cabrera, 2003)

  • Clave para distinguir a Paranomala zaragozai de las especies del grupo “capito”.

Andrés Ramírez-Ponce 2010

  • Key to the Species of Brachysternus

Male Brachysternus species are characterized by having the apex of the terminal sternite quadrate; females are characterized by having the apex of the terminal sternite moderately to deeply emarginate.

  • Clave para las Especies de Brachysternus

Los machos de las especies de Brachysternus se caracterizan por tener el apice del esternito terminal cuadrado; las hembras se caracterizan por tener el apice del estenito terminal moderadamente o profundamente emarginado.


REFERENCIAS


German Amat Garcia, GUIA PARA LA CRIA DE ESCARABAJOS, Colombia,
2005

Ross H. Arnett JR, Michael C. Thomas, Paul E. Skelley, J. Howard Frank, American Beetles, Volume II: Polyphaga: Scarabaeoidea through Curculionoidea, 2002

http://www.inbio.ac.cr/papers/insectoscr/Texto101.html

http://www.inbio.ac.cr/es/default.html

http://www-museum.unl.edu/

http://www.unl.edu/museum/research/entomology/Guide/Scarabaeoidea/Scarabaeidae/Rutelinae/Rutelinae-Overview/RutelinaeO.html

http://bugguide.net/node/view/12432/bgimage

http://www.bioone.org/doi/full/10.1649/0010-
065X%282002%29056%5B0321%3AROTSAG%5D2.0.CO%3B2

http://www.bioone.org/doi/full/10.1649/0010-
065X%282001%29055%5B0103%3AEBGRCS%5D2.0.CO%3B2

http://www.bioone.org/doi/full/10.1649/0010-
065X%282002%29056%5B0438%3ALADEFT%5D2.0.CO%3B2

http://www.bioone.org/doi/full/10.1603/0013-
8746%282000%29093%5B0408%3ATROPLS%5D2.0.CO%3B2

http://www.bioone.org/doi/full/10.1649/0010-
065X%282002%29056%5B0321%3AROTSAG%5D2.0.CO%3B2

http://www.bioone.org/doi/full/10.1603/0013-
8746%282001%29094%5B0866%3AXANAUG%5D2.0.CO%3B2

http://www.bioone.org/doi/full/10.1649/0010-
065X%282002%29056%5B0540%3ANCRFNA%5D2.0.CO%3B2

www.arthropod-systematics.de.


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