Antaeotricha floridella sp. n. is described and diagnosed from the closely similar A. albulella (Walker). The species is distributed in xeric sandhill and scrub habitats in peninsular Florida, USA, and larvae feed on Quercus species. Keys are given for pale-winged Stenomatinae and similar Gelechioidea based on external characters and genitalia.

Quercus geminata , Quercus minima , sand pine scrub

The genus Antaeotricha Zeller, 1854 (Lepidoptera: Depressariidae: Stenomatinae) is endemic to the New World and includes nearly 400 species, mostly in the Neotropics (Becker 1984). Twenty Nearctic species are known (Ferris 2013), including the one described below. Duckworth (1964) comprehensively revised the Nearctic Stenomatinae, and four species were recently described from the southwestern United States (Ferris 2010, 2012, 2013).

The second author (TSD) discovered the presently described species by dissection, as it is externally very similar to the widely distributed A. albulella (Walker, 1864) (more often called by its junior synonym A. vestalis (Zeller, 1873) [Becker 1981]). The search of other collections by JEH yielded more specimens, including ones overlooked by Duckworth. The species description necessitates a revised key to pale-colored Nearctic Stenomatinae. The species is known only from xeric habitats in peninsular Florida. This pattern of endemism of species in Florida sandhills is common among other orders of insects and arthropods but is infrequent in Lepidoptera (Deyrup 1989), so the addition of another endemic species is significant.

Stenomatinae are diagnosed by the presence of thickened, apically bifid or multifid setae on the valvae of the male genitalia (Hodges 1998) (Fig. 10: b s). The subfamily has been placed in various gelechioid families, including Oecophoridae, Elachistidae, and most recently in the resurrected Depressariidae (Heikkilä et al. 2014) based on pupal morphology and weak molecular evidence. Depressariid pupae share lateral condyles between abdominal segments. Unlike most other depressariids, stenomatines have a gnathos that is apically smooth, not scobinate or spiculate.

Antaeotricha as a genus is diagnosed by the presence of a thumb-like process on the costa of the male valva (Fig. 14: th) and by the reduction of the anterior apophyses of the female ovipositor (Fig. 18: a a) (Duckworth 1964). Most species have white or brown wings with some contrasting maculation, usually the postmedial line, but often reduced to one or two spots on the discal cell. The newly described species has totally immaculate white wings.

The two previously published keys to Antaeotricha are based on wing pattern (Barnes and Busck 1920) or genitalia (Duckworth 1964). We provide two revised keys based on maculation and genitalia that treat pale-winged species of Antaeotricha and similar gelechioids.

Dissection of genitalia follows Robinson (1976): abdomens were macerated in hot 10% aqueous KOH, brushed clean in water, stained with Chlorazol Black, and slide-mounted in Euparal or stored in glycerin. Photographs were taken with 1) a Canon PowerShot Pro1 and 2) the Auto-montage Pro 5.01 system (Synoptics Ltd.) using a JVC digital camera and Leica Z16APO lens (FSCA). Habitus photographs were taken over standard 18% gray card under tungsten or fluorescent LED lights, and genitalia photographs were lit from above and below. Postprocessing was limited to 1) stacking images with Auto-Montage and 2) using Adobe Photoshop Elements 11 to standardize the gray (for habitus) or white balance (for slides) and the Auto Contrast function for some genitalia images. The map was made with Diva-GIS version 7.5.0.0 using a county-level shape file available from the website (www.diva-gis.org) and a CSV file of georeferenced decimal-degree coordinates.

Morphological terminology for genitalia follows Klots (1970) except where superseded by Kristensen (2003).

Becker (1981) synonymized A. vestalis (Zeller, 1873) with A. albulella (Walker, 1864), and he remarked that the lectotype of A. albulella and the available specimens of A. vestalis all had black discal spots. Zeller (1873) stated that the type of Cryptolechia vestalis had white forewings “ohne jede Zeichnung” (without any marking), but the hind wings are white like the forewings. The lectotype specimen, deposited in the Museum of Comparative Zoology (Cambridge, MA, USA) is a female from Texas. Its forewings have faint black discal spots, and sternum VIII has the typical setose protuberances, which are visible without dissection.

Antaeotricha floridella is described as a new species because no other white species with similar genitalia were described by Meyrick (Clarke 1955), Walsingham (1909–1915), Walker (1864), Zeller (1854, 1855, 1873, 1877) or other authors. The West Indian Antaeotricha fauna is depauperate, with only three species (Duckworth 1969). Descriptions and illustrations of all species currently placed in Antaeotricha were examined, a task greatly facilitated by the illustration of Meyrick’s numerous species by Clarke (1955) and by the concentration of other descriptions among a few authors (e.g. Walker 1864; Walsingham 1909–1915; Busck 1911, 1920; Zeller 1854, 1877; see Becker 1984 for complete list). Almost all species are described as having some forewing maculation, and those without are some shade of brown.

The new species keys to couplet 8 in Barnes and Busck (1920: 238), requiring a new line, “forewings pure white without discal spots.” In the key of Duckworth (1964: 27), males run to couplet 13 (A. unipunctella or A. vestalis), and females run to A. osseella or A. unipunctella. New keys are provided below that include A. floridella and another species described after 1964.

Duckworth’s (1964) key is inaccurate as it pertains to the small, unicolorous species. In couplet 12 of the key, the “[g]nathos divided into two lobes at tip” could apply equally to A. osseella and A. decorosella (Busck, 1908 a) as well as to A. unipunctella and A. albulella; he correctly noted the “notched” condition of the gnathos in the species accounts. In couplet 14, the low subapical spine or tooth of the phallus (Fig. 11: s t) is stated to be present in A. osseella and absent in A. decorosella. In our dissections, the spine in A. osseella varies from sharply angulate to a low hump to entirely absent. In a specimen that appears to represent A. decorosella (MGCL slide 2166), a low rise is present. This specimen has many robust chaetae on the apical two thirds of the anellar lobe, which is diagnostic for male A. decorosella. Furthermore, the variation of the spine is as follows: A. unipunctella, absent or a low serrate ridge; A. albulella, a very low expansion but not an angulate tooth; A. floridella, present or absent. This variable character should be avoided for separating species.

Antaeotricha albulella, A. osseella, and A. floridella adults are active at the same time and location. John B. Heppner has caught all three species at the Welaka Forest Conservation Station, 28–31 July 1986. A male specimen each of A. albulella and A. floridella were collected at Pellicer Creek (Flagler Co.) on 10 April 1954 (CMNH). The road numbers in Ocala National Forest changed in 2008: Forest Road 88 is now 11, and 97 is now 09.

Antaeotricha floridella is known to feed on two species of oak: Quercus geminata and possibly Q. minima. The latter species may be misidentified, since it resembles juvenile or rhizomatous forms of other oaks (Nixon 1993). Host plants of A. albulella, recorded from pinned specimens donated to the FSCA by D.H. Habeck, include Quercus laevis Walter (turkey oak), Q. nigra L. (water oak) (with feeding habits “galls” and “leaf tier”), Q. incana W. Bartram (bluejack oak), Q. myrtifolia Willd. (myrtle oak), Q. inopina Ashe (scrub oak), and Q. chapmanii Sarg. (Chapman’s oak). The plant voucher specimens could not be located, so their identifications could not be verified.

Two plant communities in Ocala National Forest in Marion and Putnam counties, the sandhill and sand pine communities, have been collected extensively by TSD over the past several years using both mercury vapor light and ultraviolet light. Antaeotricha floridella occurs in both plant communities, as well as in strict scrub habitat with minimal canopy not surveyed by TSD. In the sandhill community, the common species of pine is Pinus palustris Miller (longleaf pine), and the common species of oak is Q. laevis. The leaves of turkey oak are deciduous, mostly falling in September and October, with a few leaves remaining on the trees during the winter. New foliage begins to appear in March and April. In the sand pine community, the predominant pine is Pinus clausa Chapman ex Engelmann (sand pine), and the common oak is Q. myrtifolia. In Ocala National Forest, myrtle oak tends to be a thicket-forming shrub. Leaves are “tardily deciduous,” meaning that a few leaves fall during the winter months, but the majority of leaf fall occurs during late February and March, just as the trees begin to flower and new leaves develop. Quercus geminata is also tardily deciduous (Godfrey 1988). The type locality of A. floridella has Q. geminata, Q. laevis, and Q. hemisphaerica in abundance, and Q. myrtifolia and Q. nigra in small numbers.

Extensive collecting in a large mesic forest near Anthony (Marion County, Florida) by TSD with mercury vapor and ultraviolet lights and sugar bait has failed to produce any specimens of A. floridella. This forest has large numbers of three species of oaks: Quercus virginiana Miller (live oak), Q. hemisphaerica Bartr. ex Willd. (laurel oak), and Q. nigra (water oak). The leaves of all of these species are tardily deciduous with primary leaf fall occurring in late February and March just prior to flowering and new leaf growth.

With minimal host information, it is open to question whether A. floridella is monophagous on Quercus geminata, oligophagous on oaks with overwintering foliage, or has more hosts. Sand live oak occurs in both plant communities and others in Florida. It occurs on the southeastern coastal plain from Virginia to Mississippi (Godfrey 1988), so the plant’s distribution cannot explain the moth’s restriction to peninsular Florida. On the other hand, a broader host range would predict occurrence in non-xeric habitats. The phenology of the immature stages is unknown, in particular of the overwintering stages. It is not obvious that A. floridella has adaptations to abiotic characteristics of xeric habitats, so affinity for some host is assumed.

A partly historical explanation for the peninsular distribution may be isolated evolution in habitat islands of sandhill and scrub (Webb 1990). Few Lepidoptera are known to be restricted to those habitats and also endemic to Florida. One moth species is known to be endemic to Florida rosemary scrub, a geometrid that feeds on Ceratiola ericoides Michx. (Deyrup 1989). Kons and Borth (2006) list 51 species of Lepidoptera that, based on preliminary evidence, may be dependent on the first kind of plant community (turkey oak-longleaf pine sandhills), but the majority of these also occur in similar habitats outside peninsular Florida. Comparable data are lacking for sand pine communities. Although most specimens of A. floridella were collected in longleaf pine sandhills or sand pine scrub, the specimens from Jonathan Dickinson State Park and Archbold Biological Station may have been collected in other kinds of scrub habitat (Myers 1990). It has not been found in collections (MEM, FSCA) from the ecologically similar Ohoopee Dunes in Georgia, although A. albulella occurs there. Kons and Borth (2006) discuss in depth the methods and caveats of associating species with xeric habitats based mainly on adult specimens, and they emphasize the need to test hypotheses of habitat dependence with further collection data.

The Antaeotricha albulella group (including A. osseella, A. unipunctella, and A. decorosella) is probably a recent radiation, with A. floridella as a peninsular vicariant. It is not simply a peripheral isolate of A. albulella, because it lacks the autapomorphies of the latter species (the broad gnathos and prominent SVIII pads). Preliminary genetic data corroborates the species’ distinct status. A specimen of A. floridella in the CNC, dissected by J.-F. Landry, has a slightly greater percentage distance than intraspecific clusters of A. albulella based on mtCO1 (J.-F. Landry, pers. comm. 2014). The sequence data are available at: http://www.boldsystems.org/index.php/Public_RecordView?processid=MNAB391-07. Study of more genetic data should be useful to clarify the A. albulella group. All species and populations should be sampled and the data analyzed with character-based phylogenetic methods to discover diagnostic apomorphies. Collection of Antaeotricha specimens across known phylogeographic discontinuities in North Central Florida and the Panhandle could demarcate the northern limit of the distribution of A. floridella (Soltis et al. 2006).

Additional species examined. Dissected specimens of several other species were examined to construct the keys, except Gonioterma crambitella (Walsingham, 1889), figured in Duckworth (1964). Unless otherwise indicated, dissection slides are assigned MGCL slide numbers and deposited in FSCA.

Antaeotricha albulella: FL, Collier Co. Fakahatchee Strand, MGCL 1953♂; FL, Collier Co., USNM slide 76303♂ (NMNH); FL, Duval Co., USNM slide 76306♂ (NMNH); FL, Escambia Co., MGCL 1691♀; FL, Highlands Co., MGCL 1699♀ (FSCA), USNM slides 76318♀, 76252♀ (NMNH); FL, Hillsborough Co., MGCL 1686♂; FL, Lee Co., USNM slide 76304♂ (NMNH); FL, Levy Co., MGCL 1681♂; FL, Miami-Dade Co., MGCL 495♂ (FSCA), USNM slides 76302♀, 135307♂ (NMNH); FL, Polk Co., USNM slide 76301♂ (NMNH); FL, Putnam Co., MGCL 1697♂; FL, Sarasota Co., MGCL 1736♂; FL, Volusia Co., USNM slide 135306♂ (NMNH); GA, Emanuel Co. Ohoopee Dunes, JEH 2970♂ (MEM); LA, St. John Parish, MGCL 1671♀; LA, St. John Parish, MGCL 1747♂; MD, Kent Co., JEH 2756♂ (NMNH); MD, Kent Co., JEH 2765♀ (NMNH); NC, Craven Co., MGCL 1670♂; NC, Craven Co., MGCL 1793♀; TX, Anderson Co., JEH 2753♂ (NMNH); TX, Anderson Co., JEH 2754♀ (NMNH); VA, Virginia Beach Co., JEH 2775♂ (NMNH); [no locality], USNM slide 135305♂ (NMNH).

A. arizonensis Ferris, 2010: AZ, Cochise Co., MGCL 1733♂; AZ, Cochise Co., MGCL 1734♀.

A. decorosella: MO, Benton Co., MGCL 2166♂ (MGCL).

A. furcata (Walsingham, 1889): AZ, Gila Co., MGCL 1735♂; TX, Jeff Davis Co., MGCL 2074♀.

A. fuscorectangulata Duckworth, 1964: AZ, Cochise Co., MGCL 1728♂.

A. haesitans (Walsingham, 1912): TX, Hidalgo Co., MGCL 2065♂.

A. humilis (Zeller, 1855): FL, Alachua Co., MGCL 1677♂; FL, Marion Co., MGCL 1678♀.

A. irene (Barnes and Busck, 1920): TX, Hidalgo Co., MGCL 2066♂.

A. leucillana (Zeller, 1854): FL, Alachua Co., MGCL 1689♂; FL, Alachua Co., MGCL 1690♀; ME, Waldo Co., MGCL 2076♂.

A. lindseyi (Barnes and Busck, 1920): AZ, Cochise Co., MGCL 2075♂.

A. manzanitae Keifer, 1937: CA, El Dorado Co., MGCL 1731♂ (MGCL); CA, El Dorado Co., MGCL 1732♀ (MGCL).

A. osseella: FL, Alachua Co., MGCL 2077F, 2966F, 2967♂; FL, Escambia Co., MGCL 1676♀; FL, Highlands Co., MGCL 1675♂; FL, Marion Co., MGCL 1698♂, 2400♂; FL, Putnam Co., MGCL 1713♂; MO, Carter Co, MGCL 2164♂ (MGCL); MO, Carter Co., MGCL 2165♀ (MGCL); NC, Craven Co., MGCL 1711♂; NM, Otero Co., MGCL 1721♀.

A. schlaegeri (Zeller, 1854): CANADA, Nova Scotia, MGCL 2375♂; USA, AZ, Santa Cruz Co., MGCL 1702♀; FL, Alachua Co., MGCL 1687♂, 1688♀; MA, Plymouth Co., MGCL 2365♂; MA, Plymouth Co., MGCL 2366♀; MO, Barry Co., MGCL 2370♀; MO, Clay Co., MGCL 2367♂; NC, Craven Co., MGCL 2373♂; TN, Sullivan Co., MGCL 2374♂.

A. unipunctella: FL, Escambia Co., MGCL 1714♂; FL, Hernando Co., MGCL 2992♀; FL, Highlands Co., MGCL 2078♀, 2399♂; FL, Manatee Co., MGCL 1673♂, 2167♀; FL, Marion Co., MGCL 1674♀, 1712♂.

A. utahensis: AZ, Cochise Co., MGCL 1703♂; NM, Grant Co., MGCL 1720♂.

Autosticha kyotensis (Matsumura, 1931): FL, Santa Rosa Co., MGCL 485♂, 486♀; FL, Gainesville, MGCL 487♂.

Durrantia piperatella (Zeller, 1873): OK, Latimer Co., MGCL 1727♂; TX, Brewster Co., JEH 2761♂, 2762♀ (NMNH).

Gonioterma mistrella (Busck, 1907): MO, Barton Co., MGCL 1695♂; MO, Newton Co., MGCL 1696♀.

Inga cretacea (Zeller, 1873): MO, Barry Co., MGCL 2062♂; AR, Washington Co., MGCL 2063♀.

Pseuderotis obiterella (Busck, 1908 b): NC, Craven Co., MGCL 1726♂.

We thank Richard Brown (MEM), John Brown (retired NMNH), Mark Deyrup (Archbold Biol. Station), John Rawlins (CMNH), and Jim Vargo (Mishawaka, Indiana) for lending or donating specimens. Philip Perkins (Museum of Comparative Zoology) loaned the lectotype specimen of A. vestalis (Zeller) for examination. Marc Minno and the late Dale H. Habeck (University of Florida) reared adults from larvae, providing important ecological information. Patti Anderson (FDACS-DPI) kindly confirmed identifications of botanical samples. Clifford Ferris informed us about the complexities of Antaeotricha and the problems with previous publications. Jean-François Landry dissected specimens in the Canadian National Collection, provided preliminary analysis of CO1 sequence data, and gave valuable suggestions to improve the research. We thank Richard Brown, Paul Skelley (FDACS-DPI), Jason Stanley (FDACS-DPI), Greg Hodges (FDACS-DPI), and an anonymous reviewer for many helpful corrections and suggestions for the manuscript. This is FDACS-DPI Entomology Contribution No. 1285.