Belongs within: Riodinidae.
Contains: Lemoniadina.
The Nymphidiini is a clade of Neotropical butterflies including the majority of myrmecophilous Riodinidae.
The multifarious methods of myrmecophilous metalmarks
Published 24 June 2023
Of the various recognised families of butterflies, one that tends to receive less attention is the Riodinidae or metalmarks. Whereas other families can be found across the world, the metalmarks are very predominantly a Neotropical affair. Nevertheless, they are certainly not a group without their interest. And one of the largest and most interesting subgroups of the metalmarks is the Nymphidiini.
As currently circumscribed, the tribe Nymphidiini include over 300 species divided between several subtribes (Hall 2002; Seraphim et al. 2018). Most (but not all) are not brightly coloured as butterflies go; browns and whites seem to be a regular theme. Wings of many Nymphidiini are noticeably greasy. Adults of individual subtribes may be characterised by features of the male terminalia, but the tribe as a whole is primarily united by molecular data and features of the larvae. This last point is where things get interesting, as many of said larval features are related to myrmecophily.
Myrmecophily, for those not familiar with the term, refers to associations with ants. Nymphidiin caterpillars (where they have been identified) typically possess small eversible tentacles near the rear end of the body, and often closer to the front as well. These tentacular organs release substances attractive to ants: either droplets of sweet liquid, or attractive pheromones (Pierce & Dankowicz 2022). Balloon-shaped setae may be present near the head that perform a similar function (DeVries et al. 2004). Nymphidiin caterpillars also possess vibratory papillae at the front of the thorax that are rubbed against the top of the head to produce substrate-borne calls. Caterpillars of the subtribe Zabuellina also possess a secretory gland on the prosternum that they present to ants investigating their balloon setae (DeVries et al. 2004; Seraphim et al. 2018). Though the larvae of many nymphidiins have not yet been identified, enough have to know that myrmecophily is characteristic of the lineage. The greasy wings of many nymphidiins may also evidence their myrmecophilous habits; greasy wings may allow butterflies emerging from their pupa to more easily escape their once attendant ants.
At the most basic level, caterpillars attract ants to provide a defence from other predators. Some, however, take the relationship further, and often not to their attendant’s advantage (Pierce & Dankowicz 2022). Caterpillars may feed on honeydew produced by plant-sucking bugs being attended by the ants or on the bugs themselves. Aricoris arenarum begins life feeding on honeydew but eventually moves into host ants’ nest, inducing the ants to feed it via trophallaxis. Members of the subtribe Pachythonina were recently discovered to have heavily armoured caterpillars that can feed on the brood of the ants themselves.
A notable exception to nymphidiin myrmecophily may be found among the subtribe Stalachtina, species of which also differ from other members of the tribe in being brightly, aposematically coloured. Caterpillars of Stalachtina feed on trees of the family Simaroubaceae and many stalachtinans may have foregone relying on ants for defence in favour of sequestering plant toxins. Nevertheless, some species of the genus Stalachtis retain tentacular organs as caterpillars and still attract ants. As a result, they manage to keep a boot in both camps.
Systematics of Nymphidiini
Synapomorphies (from Hall & Harvey 2002): Vibratory papillae present on prothorax of larva; larval abdominal segment one with spiracle ventral, below lateral fringe of setae.
<==Nymphidiini [Lemoniadini, Lemoniini] |--+--LemoniadinaHH02 | `--+--TheopeinaHH02 | | |--Behemothia godmaniiHH02 | | |--Protonymphidia sentaHH02 | | |--CalicosamaHH02 | | `--TheopeHH02 | | |--T. eurygoninaHH02 | | `--T. publius (Felder 1861)FS55 | `--NymphidiinaHH02 | |--Menander menanderHH02 | |--CatocyclotisHH02 | |--NymphidiumHH02 | |--Mycastor nealcesHH02, KP19 | |--Adelotypa annuliferaHH02 | |--ZabuellaHH02 | |--Calospila cilissaHH02 | |--Setabis lagusHH02 | |--Calociasma nycteus [=Synargis nycteus]HH02 | `--ZelotaeaHH02 | |--Z. albovata [=Ematurgina albovata]HH02 | |--Z. leucotopus [=Ematurgina leucotopus]HH02 | |--Z. nivosa [=Ematurgina nivosa]HH02 | `--Z. watkinsi [=Ematurgina watkinsi]HH02 `--AricorinaHH02 |--Ariconias Hall & Harvey 2002HH02 | |--A. albinus (Felder & Felder 1861) [=Lemonias albinus, Audre albinus]HH02 | `--A. glaphyra (Westwood 1851) (see below for synonymy)HH02 `--Aricoris Westwood 1851 (see below for synonymy)HH02 | i. s.: A. arenarum (Schneider 1937)HH02 | A. zachaeus (Fabricius 1798) [incl. A. zachea (Godart 1824)]HH02 |--+--+--*A. constantius (Fabricius 1793) (see below for synonymy)HH02 | | `--A. terias (Godman 1903) [=*Eiseleia terias; incl. A. pichanalensis (Miller & Miller 1972)]HH02 | `--+--A. gauchoana (Stichel 1910)HH02 | |--A. colchis (Felder & Felder 1865)HH02 | `--A. middletoni (Sharpe 1890) [incl. A. diamantina (Callaghan 1999), A. philene (Stichel 1916)]HH02 `--+--+--A. chilensis (Felder & Felder 1865) (see below for synonymy)HH02 | |--A. cinericia (Stichel 1910) (see below for synonymy)HH02 | `--A. notialis (Stichel 1910) [incl. A. mesopotamica (Hayward 1968), A. susanae (Orfila 1953)]HH02 `--+--+--A. aurinia (Hewitson 1863)HH02 | |--A. domina (Bates 1868)HH02 | |--A. incana (Stichel 1910) [incl. A. drucei (Giacomelli 1914)]HH02 | `--A. montana (Schneider 1937) (see below for synonymy)HH02 `--+--A. campestris (Bates 1868)HH02 |--A. caracensis (Callaghan 2001)HH02 |--A. epulus (Cramer 1775) (see below for synonymy)HH02 |--A. erostratus (Westwood 1851) [incl. A. antaeus (Seitz 1916), A. insularis (Lathy 1932)]HH02 |--A. hubrichi (Stichel 1926) [incl. A. almironensis (Schweizer & Kay 1941)]HH02 |--A. indistincta (Lathy 1932) [incl. A. ina (Schweizer & Kay 1941)]HH02 |--A. propitia (Stichel 1910)HH02 `--A. signata (Stichel 1910)HH02
Ariconias glaphyra (Westwood 1851) [=Lemonias glaphyra; incl. A. campicola (Seitz 1916); A. modesta (Mengel 1902)]HH02
Aricoris Westwood 1851 [incl. Audre Hemming 1934, Eiseleia Miller & Miller 1972, Lemonias Hoffmannsegg 1818 non Hübner 1807, Melanope Röber 1892]HH02
Aricoris chilensis (Felder & Felder 1865) [incl. A. affinis (Schweizer & Kay 1941), A. catamarquense (Hayward 1968), A. cisandrina (Seitz 1916), A. cosquinia (Giacomelli 1928), A. dovina (Schaus 1902), A. umbrata (Giacomelli 1928)]HH02
Aricoris cinericia (Stichel 1910) [incl. A. precaria (Schweizer & Kay 1941), A. similis (Schweizer & Kay 1941)]HH02
*Aricoris constantius (Fabricius 1793) [incl. A. bahiana Felder & Felder 1865, A. monotona Stichel 1910, A. tisiphone Westwood 1851, A. tutana (Godart 1824)]HH02
Aricoris epulus (Cramer 1775) [=*Audre epulus; incl. A. albimaculata (Lathy 1932), A. epula (Hübner 1821), A. epule (Hübner 1819), A. pasquita (Stichel 1910)]HH02
Aricoris montana (Schneider 1937) [incl. A. erycina (Schweizer & Kay 1941), A. nordensis (Callaghan 2001)]HH02
*Type species of generic name indicated
References
DeVries, P. J., B. C. Cabral & C. M. Penz. 2004. The early stages of Apodemia paucipuncta (Riodinidae): myrmecophily, a new caterpillar ant-organ and consequences for classification. Milwaukee Public Museum, Contributions in Biology and Geology 102: 1–13.
[FS54] Franz, E., & H. Schröder. 1954. Tagfalter (Lep. Rhopalocera) aus El Salvador. Senckenbergiana Biologica 35: 75–87.
Hall, J. P. W. 2002. Phylogeny of the riodinid butterfly subtribe Theopeina (Lepidoptera: Riodinidae: Nymphidiini). Systematic Entomology 27: 139–167.
[HH02] Hall, J. P. W., & D. J. Harvey. 2002. Basal subtribes of the Nymphidiini (Lepidoptera: Riodinidae): phylogeny and myrmecophily. Cladistics 18: 539–569.
[KP19] Kawahara, A. Y., D. Plotkin, M. Espeland, K. Meusemann, E. F. A. Toussaint, A. Donath, F. Gimnich, P. B. Frandsen, A. Zwick, M. dos Reis, J. R. Barber, R. S. Peters, S. Liu, X. Zhou, C. Mayer, L. Podsiadlowski, C. Storer, J. E. Yack, B. Misof & J. W. Breinholt. 2019. Phylogenomics reveals the evolutionary timing and pattern of butterflies and moths. Proceedings of the National Academy of Sciences of the USA 116 (45): 22657–22663.
Pierce, N. E., & E. Dankowicz. 2022. Behavioral, ecological and evolutionary mechanisms underlying caterpillar-ant symbioses. Current Opinion in Insect Science 52: 100898.
Seraphim, N., L. A. Kaminski, P. J. DeVries, C. Penz, C. Callaghan, N. Wahlberg, K. L. Silva-Brandão & A. V. L. Freitas. 2018. Molecular phylogeny and higher systematics of the metalmark butterflies (Lepidoptera: Riodinidae). Systematic Entomology 43: 407–425.