Spilomelinae is a very species-rich subfamily of the lepidopteran family Crambidae, the crambid snout moths. With 4,180 described species in 351 genera worldwide, it is the most speciose group among pyraloids.
Description Imagines – the adult life stage – vary considerably in size: the forewing span ranges from 11.5 mm e.g. in Metasia to 50 mm in the robust-bodied Eporidia. In resting position, the moths exhibit a characteristic triangular shape, with the wings usually folded over the abdomen, the forewings covering the hindwings. Some Spilomelinae diverge from this common resting pattern, like Maruca with widely spread wings, and Atomopteryx and Lineodes with narrow wings folded along the body. All Spilomelinae moths have well-developed compound eyes, antennae and mouthparts, although in the genera Niphopyralis and Siga the proboscis is lost.
Synapomorphic characters of the subfamily comprise minute or obsolete maxillary palpi, ventrally projecting fornix tympani, and the female genitalia's ductus bursae with a weak sclerotization or a granulose texture. The moths are furthermore characterized by an often bilobed praecinctorium, pointed spinula, and the absence of chaetosemata and of a retinacular hook. A gnathos or pseudognathos can be present or absent and is therefore of little diagnostic value, except for several genera of Agroterini, where the gnathos has a well-developed medial process.
Food plants Food plant use is diverse within Spilomelinae, ranging from ferns over gymnosperms to a wide spectrum of angiosperms. The larvae of Niphopyralis live in nests of weaver ants, where they feed on ant larvae. Many Steniini caterpillars are detritivores.
Many Spilomelinae tribes have a narrow food spectrum, with the larvae feeding on plants of only one or a few plant families, e.g. Lineodini on Solanaceae, Hydririni primarily on Sapindaceae and Convolvulaceae, and Trichaeini on Rubiaceae.
Economic impact A number of Spilomelinae are considered "pest species", with their larvae feeding on a variety of economically important crops. Notable representatives are the genera of Leucinodes and Neoleucinodes with larvae feeding on Solanaceae, Cnaphalocrocis and Marasmia damaging Poaceae like Oryza, Sorghum and Zea, the legume pod borers of the genus Maruca on Fabaceae and Amaranthaceae, and Spoladea, who feeds on a variety of different agriculturally important plant families.
The box tree moth, Cydalima perspectalis, whose larvae feed on box trees, a prominent ornamental plant in many parks and gardens, has been accidentally introduced to Europe in the mid-2000s and to North America in 2018.
Systematics
Until the late 1990s, Spilomelinae were included in the subfamily Pyraustinae as tribe Spilomelini.
In the past, Spilomelinae were believed to be polyphyletic. However, a recent phylogenetic study by Mally et al. (2019), based on molecular genetic and morphological data, found the subfamily to be monophyletic. The study's authors furthermore proposed 13 tribes within Spilomelinae: Agroterini Acloque, 1897 Asciodini Mally, Hayden, Neinhuis, Jordal & Nuss, 2019 Herpetogrammatini Mally, Hayden, Neinhuis, Jordal & Nuss, 2019 Hydririni Minet, 1982 Hymeniini Swinhoe, 1900 Lineodini Amsel, 1956 Margaroniini Swinhoe & Cotes, 1889 Nomophilini Kuznetzov & Stekolnikov, 1979 Spilomelini Guenée, 1854 Steniini Guenée, 1854 Trichaeini Mally, Hayden, Neinhuis, Jordal & Nuss, 2019 Udeini Mally, Hayden, Neinhuis, Jordal & Nuss, 2019 Wurthiini Roepke, 1916
"Non-euspilomeline" tribes Hydririni, Lineodini, Udeini and Wurthiini share several plesiomorphic characters with the sister group of Spilomelinae, the Pyraustinae. These plesiomorphies are: absence of longitudinal strips on the male abdominal segment 8; male genitalia with a straight to concave valva costa and a phallus with an evenly sclerotized apodeme; female genitalia with a lanceolate "ediacaroid" signum in the corpus bursae and in several taxa with an appendix bursae attached to the corpus bursae.
Due to these plesiomorphies, these four Spilomelinae tribes are referred to as "non-euspilomeline" tribes as opposed to the monophyletic "euspilomeline" group that represents a more derived group of Spilomelinae. The "non-euspilomeline" tribes form a paraphylum as they do not comprise the "euspilomelines".
"Euspilomeline" tribes
The tribes Agroterini, Margaroniini, Spilomelini, Herpetogrammatini, Hymeniini, Asciodini, Trichaeini, Steniini and Nomophilini form the monophylum of "euspilomelines" (Greek eu- for "good" or "true"), all sharing a common ancestor. The synapomorphies of euspilomelines are: male abdominal tergite 8 with an emarginate anterior edge; male genitalia with partly sclerotized hair pencils on the anterior edge of vinculum-tegumen connection, with a convex valva costa, and the phallus without a coecum and the sclerotization of the phallus apodeme reduced to a ventral, longitudinally sclerotized strip along the manica; female genitalia with a longitudinal membranous strip in the antrum, and the lack of a strongly sclerotised colliculum between antrum and ductus seminalis.
Genera currently unplaced in any Spilomelinae tribe Based on the morphological synapomorphies and characteristics of these tribes, Mally et al. (2019) assigned numerous Spilomelinae genera to these proposed tribes, so that about two thirds of the 339 Spilomelinae genera are placed in these tribes, leaving 132 genera currently unplaced:
Aboetheta Turner, 1914 Acicys Turner, 1911 Aediodina Strand, 1919 Agrammia Guenée, 1854 Almonia Walker, 1866 Ametrea Munroe, 1964 Archernis Meyrick, 1886 (= Chrysommatodes Warren, 1896, Metoportha Meyrick, 1894, Protonoceras Warren, 1890) Arxama Walker, 1866 Atelocentra Meyrick, 1884 Auchmophoba Turner, 1913 Bacotoma Moore, 1885 (= Epactoctena Meyrick, 1937, Platamonia Lederer, 1863, Platamonina J. C. Shaffer & Munroe, 2007) Cangetta Moore, 1886 Carthade Snellen, 1899 Chabula Moore, 1886 Chromodes Guenée, 1854 Cissachroa Turner, 1937 Coelorhyncidia Hampson, 1896 Coptobasis Lederer, 1863 Coremata Amsel, 1956 Cotachena Moore, 1885 Criophthona Meyrick, 1884 Camptomastix Warren, 1892 (= Camptomastyx Hampson, 1896) Cangetta Moore, 1886 (= Blechrophanes Turner, 1937) Carthade Snellen, 1899 (= Chartade Neave, 1939) Cavifrons Zeller, 1872 Ceratarcha Swinhoe, 1894 Chabula Moore, 1886 Chromodes Guenée, 1854 Cissachroa Turner, 1937 Coelorhyncidia Hampson, 1896 Coptobasis Lederer, 1863 Coremata Amsel, 1956 (= Culcita Amsel, 1957) Cotachena Moore, 1885 (= Mesothyris Warren, 1892, Syndicastis Meyrick, 1889) Criophthona Meyrick, 1884 (= Conoprora Turner, 1913) Daulia Walker, 1859 (= Girtexta Swinhoe, 1890) Deuterarcha Meyrick, 1884 Deuterophysa Warren, 1889 Dichocrocis Lederer, 1863 (= Zebrodes Warren, 1896) Discothyris Warren, 1895 Dracaenura Meyrick, 1886 Duzulla Amsel, 1952 Ebuleodes Warren, 1896 Ectadiosoma Turner, 1937 Elbursia Amsel, 1950 Eudaimonisma T. P. Lucas, 1902 Eulepte Hübner, 1825 (= Acrospila Lederer, 1863) Eurybela Turner, 1908 Eustenia Snellen, 1899 Furcivena Hampson, 1896 Gadessa Moore, 1885 Gethosyne Warren, 1896 Glauconoe Warren, 1892 Goniorhynchus Hampson, 1896 Heterudea Dognin, 1905 Hyalea Guenée, 1854 Indogrammodes Kirti & Rose, 1989 Ischnurges Lederer, 1863 (= Nesolocha Meyrick, 1886) Legrandellus J. C. Shaffer & Munroe, 2007 Lepidoneura Hampson, 1896 Leucinodella Strand, 1918 Leucochromodes Amsel, 1956 Leucophotis Butler, 1886 Lipararchis Meyrick, 1934 Luma Walker, 1863 (= Pelena Moore, 1886, Pelina Hampson, 1897, Petena Neave, 1940) Macaretaera Meyrick, 1886 (= Trichoptychodes Swinhoe, 1894, Trigonophylla Turner, 1937) Macrobela Turner, 1939 Malaciotis Meyrick, 1934 Malickyella Mey & Speidel, 2010 Meekiaria Munroe, 1974 Merodictya Warren, 1896 Mesocondyla Lederer, 1863 Metallarcha Meyrick, 1884 (= Panopsia Turner, 1913) Metoeca Warren, 1896 Metraeopsis Dognin, 1905 Microgeshna J. C. Shaffer & Munroe, 2007 Microphysetica Hampson, 1917 (= Falx Amsel, 1956, Falcimorpha Amsel, 1957) Mimudea Warren, 1892 Mukia Amsel, 1954 Myriostephes Meyrick, 1884 Myrmidonistis Meyrick, 1887 Nacoleia Walker, 1859 (= Aplomastix Warren, 1890, Orthocona Warren, 1896, Semioceros Meyrick, 1884) Nankogobinda Rose & Kirti, 1986 Nausinoe Hübner, 1825 (= Lepyrodes Guenée, 1854, Phalangiodes Guenée, 1854) Nausinoella J. C. Shaffer & Munroe, 2007 Neostege Hampson, 1910 Nevrina Guenée, 1854 Nistra Walker, 1859 Notesia Yamanaka, 1992 Ommatobotys J. C. Shaffer & Munroe, 2007 Orphnophanes Lederer, 1863 (= Syntomodora Meyrick, 1894) Orthospila Warren, 1890 Osiriaca Walker, 1866 (= Myriotis Meyrick, 1885) Otiophora Turner, 1908 Paramecyna Amsel, 1961 Pectinobotys Munroe, 1959 Pelinopsis Dognin, 1905 Physematia Lederer, 1863 Piletocera Lederer, 1863 (= Alutefa Swinhoe, 1900, Danaga Moore, 1885, Diplotyla Meyrick, 1886, Ellogima Turner, 1913, Erebangela Meyrick, 1886, Graphicopoda Butler, 1886, Hormatholepis Butler, 1886, Ptilaeola Meyrick, 1886, Rinecera Butler, 1884, Sematosopha Meyrick, 1937, Strepsimela Meyrick, 1886) Plateopsis Warren, 1896 Platygraphis Dyar, 1918 Pleonectoides Hampson, 1891 Polythlipta Lederer, 1863 Praeacrospila Amsel, 1956 Praephostria Amsel, 1956 Pramadea Moore, 1888 Preneopogon Warren, 1896 Prionopaltis Warren, 1892 Prorodes Swinhoe, 1894 (= Idiostrophe Warren, 1896) Proternia Meyrick, 1884 Protonoceras Warren, 1890 Pycnarmon Lederer, 1863 (= Aripana Moore, 1886, Entephria Lederer, 1863, Eutrichotis Swinhoe, 1900, Pyralocymatophora Strand, 1918, Satanastra Meyrick, 1890) Pylartes Walker, 1863 Pyradena Munroe, 1958 Ravanoa Moore, 1885 Rehimena Walker, 1866 Rhimphaliodes Hampson, 1893 (= Rhimphaleodes Hampson, 1896) Rhynchetria Klunder van Gijen, 1913 Sagariphora Meyrick, 1894 Sameodesma Hampson, 1918 Sedenia Guenée, 1854 Sericophylla Turner, 1937 (= Sericophora Turner, 1937) Stenorista Dognin, 1905 Syngropia Hampson, 1912 Syntrita Dognin, 1905 Tabidia Snellen, 1880 Tanaophysopsis Munroe, 1964 Tasenia Snellen, 1901 Torqueola Swinhoe, 1906 Trichoceraea Sauber in G. Semper, 1902 Trigonobela Turner, 1915 Trithyris Lederer, 1863 Troctoceras Dognin, 1905 Tylostega Meyrick, 1894 Voliba Walker, 1866 (= Gabrisa Walker, 1866, Stereocopa Meyrick, 1885) Xanthomelaena Hampson, 1896 Zagiridia Hampson, 1897
Genera excluded from Spilomelinae Aporocosmus Butler, 1886 was transferred to Odontiinae, Orthoraphis Hampson, 1896 to Lathrotelinae, Hydropionea Hampson, 1917 and Plantegumia Amsel, 1956 to Glaphyriinae, and Prooedema Hampson, 1896 to Pyraustinae.
See also List of crambid genera
References
External links