Ithomiini

Taxobox
name = Ithomiini

---

image_caption = "Pteronomyia apuleia" from Bolivia
regnum = Animalia
phylum = Arthropoda
classis = Insecta
ordo = Lepidoptera
unranked_familia = Rhopalocera
superfamilia = Papilionoidea
familia = Nymphalidae
subfamilia = Danainae
tribus = Ithomiini
diversity_link = see text.
diversity = c.370 spp.
subdivision = 43 genera. See text.
subdivision_ranks = Genera

Ithomiini is a butterfly tribe in the nymphalid subfamily Danainae. Some authors consider the group to be a subfamily (Ithomiinae). These butterflies are exclusively Neotropical, found in humid forests from sea-level to 3000 m, from the southwestern United States to Argentina. There are around 370 species in some 40-45 genera.

Ithomiini biology

Ithomiines are unpalatable because their adults seek out and sequester pyrrolizidine alkaloids from plants that they visit, especially composit flowers (Asteraceae) and wilted borages (Boraginaceae). The slow-flying adults are Müllerian mimics of each other as well as of many other Lepidoptera. Identification of adult ithomiines relies on hindwing venation and male androconial scales (sex brushes located on the hindwing costa).

The group has repeatedly been proposed as biological indicators of ecological conditions or biological diversity within neotropical forests, but individual sites harbor between 10 and 50 species, for the most part, and beta diversity is often great, even over relatively short distances.

Ithomiine larvae feed mostly on Solanaceae host plants. Exceptions are the more basal genera "Tithorea", "Aeria", and "Elzunia" that, like "Tellervo" and some Danainae, feed on Echiteae vines (Apocynaceae, Apocynoideae), as well as "Megoleria" and "Hyposcada" that feed on Gesneriaceae.

The local abundance of ithomiine butterflies in the Amazon forest, the lack of observations of predation, and their “peculiar smell” lead Henry Walter Bates in 1867 to suggest that these organisms should be chemically defended. This was first experimentally demonstrated in 1889 when Thomas Belt fed ithomiines (that he called “Heliconii”) to birds, the spider "Nephila", and the white faced monkey "Cebus capucinus". The butterflies were consistently rejected, but other insects were eaten. Lincoln P. Brower in 1964 also showed that adults of "Ithomia drymo pellucida" were rejected by the bluejay "Cyanocitta cristata bromia", and Haber showed that nine species of birds also rejected several ithomiine species. Besides, Vasconcellos-Neto and Lewinsohn demonstrated that the neotropical orb-weaving spider "Nephila clavipes" released unharmed 14 species of field-caught ithomiine butterflies.

The source of the protecting chemicals in the bodies of adult ithomiines proved not to be their larval host plants, as was first suggested, but rather in plants visited by the butterflies. Adults of ithomiine, mainly males, visit flowers of some Boraginaceae, ("Tournefortia", "Heliotropium"), Asteraceae (mostly in the tribe Eupatorieae, and rarely on "Senecio" species), Apocynaceae ("Prestonia", belonging to the tribe Echiteae) and Orchidaceae ("Epidendrum paniculatum"). Dead or withered plants are also visited and, when feeding on these plants, the butterflies scratch the tissues with their legs and suck the oozing sap. These plants are known to contain pyrrolizidine alkaloids, indicating their role as chemical sources for sequestration. Other butterfly and moth species that sequester pyrrolizidine alkaloids (Danainae, Ctenuchidae, and Arctiidae) also visit similar sources. The first demonstration that pyrrolizidine alkaloids were involved in the chemical defense of insects was given by Thomas Eisner, who showed that the spiders "Nephila" and "Argiope" rejected adults of the arctiid moth "Utetheisa ornatrix" that contain pyrrolizidine alkaloids from their larval host plant, "Crotalaria" (Fabaceae: Crotalarieae). Eisner's best-selling popular science book "For love of insects" tells the story of this exciting discovery.

Ithomiini classification

The subtribes in the Ithomiini help to organize the 43 recognized genera, but this group is the subject of ongoing molecular, phylogenetic, and morphological research, and the classification presented below will no doubt be refined in the near future.

The sister group to the tribe Ithomiini is either the small tribe Tellervini (containing the single Australasian genus "Tellervo") or the larger tribe Danaini. The relationships of the three tribes in the subfamily Danainae are still unclear.

* Source: [http://www.nymphalidae.net/Classification/Higher_class.htm The higher classification of Nymphalidae, at Nymphalidae.net]
* Note: A species list with proposed new tribes for subfamily Ithomiinae is available from Keith Willmott at [http://www.flmnh.ufl.edu/butterflies/neotropica/ith_list.html] .
* Note: Names preceded by an equal sign ( = ) are synonyms, homonyms, rejected names or invalid names.

Tribe Ithomiini Godman & Salvin, 1879
* (Subtribe Tithoreina Fox, 1940)
** "Elzunia" Bryk 1937
** "Tithorea" Doubleday 1847 ( = "Hirsutis" Haensch 1909)
** "Aeria" Hübner 1816
* (Subtribe Melinaeina Clark, 1947)
** "Athesis" Doubleday 1847 ( = "Roswellia" Fox 1948
** "Eutresis" Doubleday 1847
** "Athyrtis" Felder & Felder 1862
** "Paititia" Lamas 1979
** "Olyras" Doubleday 1847
** "Patricia" Fox 1940
** "Melinaea" Hübner 1816 ( = homonym "Melinaea" Bates 1862; = "Czakia" Kremky 1925)
* (Subtribe Mechanitina Bar, 1878)
** "Methona" Doubleday 1847 ( = "Gelotophye" d’Almeida 1940)
** "Thyridia" Hübner 1816 ( = "Xanthocleis" Boisduval 1870; = "Aprotopus" Kirby 1871; = "Aprotopos" Kirby 1871)
** "Scada" Kirby 1871 ( = homonym "Salacia" Hübner 1823; = "Heteroscada" Schatz 1886)
** "Sais" Hübner 1816
** "Forbestra" Fox 1967
** "Mechanitis" Fabricius 1807 ( = homonym "Nereis" Hübner 1806; = unavailable name "Hymenitis" Illiger 1807; = "Epimetes" Billberg 1820)
* (Subtribe Napeogenina)
** "Aremfoxia" Réal 1971
** "Epityches" d'Almeida 1938 ( = homonym "Tritonia" Geyer 1832)
** "Hyalyris" Boisduval 1870 ( = "Oreogenes" Stichel 1899)
** "Napeogenes" Bates 1862 ( = homonym "Ceratonia" Boisduval 1870; = "Choridis" Boisduval 1870)
** "Hypothyris" Hübner 1821 ( = "Mansueta" d'Almeida 1922; = "Pseudomechanitis" Röber 1930; = "Garsauritis" d'Almeida 1938; = "Rhodussa" d'Almeida 1939)
* (Subtribe Ithomiina Godman & Salvin, 1879)
** "Placidina" d'Almeida 1928 ( = "Placidula" d'Almeida 1922)
** "Pagyris" Boisduval 1870 ( = "Miraleria" Haensch 1903)
** "Ithomia" Hübner 1816 ( = "Dynothea" Reakirt, 1866)
* (Subtribe Oleriina)
** "Megoleria" Constantino 1999
** "Hyposcada" Godman & Salvin 1879
** "Oleria" Hübner 1816 ( = "Leucothyris" Boisduval 1870; = "Ollantaya" Brown & Freitas 1994)
* (Subtribe Dircennina d'Almeida, 1941)
** "Ceratinia" Hübner 1816 ( = "Calloleria" Godman & Salvin 1879; = "Epileria" Rebel 1902; = "Teracinia" Röber 1910)
** "Callithomia" Bates 1862 ( = "Cleodis" Boisduval 1870; = "Epithomia" Godman & Salvin 1879; = "Corbulis" Boisduval 1870; = "Leithomia" Masters 1973)
** "Dircenna" Doubleday 1847
** "Hyalenna" Forbes 1942
** "Episcada" Godman & Salvin 1879 ( = "Ceratiscada" Brown & d’Almeida 1970; = "Prittwitzia" Brown, Mielke & Ebert 1970)
** "Haenschia" Lamas 2004
** "Pteronymia" Butler & Druce 1872 ( = "Ernicornis" Capronnier 1874; = "Parapteronymia" Kremky 1925; = "Talamancana" Haber, Brown & Freitas 1994)
* (Subtribe Godyridina)
** "Velamysta" Haensch 1909
** "Godyris" Boisduval 1870 ( = "Dismenitis" Haensch 1903; = "Dygoris" Fox 1945)
** "Veladyris" Fox 1945
** "Hypoleria" Godman & Salvin 1879 ( = homonym "Pigritia" d’Almeida 1922; = homonym "Pigritina" Hedicke 1923; = homonym "Heringia" d’Almeida 1924)
** "Brevioleria" Lamas 2004
** "Mcclungia" Fox 1940
** "Greta" Hemming 1934 ( = homonym "Hymenitis" Hübner 1819; = "Hypomenitis" Fox 1945)
** "Heterosais" Godman & Salvin 1880 ( = "Rhadinoptera" d'Almeida 1922)
** "Pseudoscada" Godman & Salvin 1879 ( = "Languida" d’Almeida 1922)

References

* Lamas, G. (1999). Nymphalidae II Pt. 3 Ithomiinae. In: E. Bauer & T. Frankenbach (Eds.), "Butterflies of the World". (pp. 1-17). Keltern, Germany: Goecke & Evers.
* See Links.

ee also

* Mimicry
* Animal coloration

External links

*commonscat-inline|Ithomiini
* [http://www.flmnh.ufl.edu/butterflies/neotropica/ith_list.html Illustrated Checklist] Florida Museum
* [http://tolweb.org/Ithomiini TOL]
* [http://www.nymphalidae.net/home.htm Nymphalidae]
* [http://www.ucl.ac.uk/taxome/jim/ithinf.htm General information on ithomiine butterflies]
* [http://www.pteron-world.com/topics/classfication/nymphalidae/danainae/ithomiini/mechanitini.html Pteron] In Japanese but
binomial names. Three page. This page is "Mechanitis".