Sympistis eleaner Adams

Adams, James K. & Schmidt, B. Christian, 2018, A new species of Sympistis Huebner from Sapelo Island, Georgia, USA (Lepidoptera, Noctuidae, Oncocnemidinae), ZooKeys 788, pp. 79-86 : 81-84

Sympistis eleaner Adams sp. n. Figs 1, 2, 9-11

Type material examined.

All specimens from the US. Holotype male (Fig. 1). Georgia: McIntosh Co., Sapelo Island, Dune habitat, just S of Beach Rd., light trap, 31°23'26.5"N, 81°15'54.5"W, May 6-7, 2016, James K. Adams, DNA voucher # CNCLEP00119937 [CNC]. Paratypes (3 males, 2 females). Georgia: Same location as holotype, May 7-8, 2016 (2 males); McIntosh Co., Sapelo Island, Greenhouses, 21-22 April 2017, MV light sheet, L. A. Durden & T. Matson, (1 female); McIntosh Co., Sapelo Island, nr. UGA dorms, 31°23'54"N, 81°16'51"W, 9 May 2017, B. Scholtens (1 female; Fig. 2); McIntosh Co., Sapelo Island, "Short Cut" Rd., 31°24'36"N, 81°17'3"W, 9-10 May 2017, light trap, J. Adams and B. Scholtens (1 male) [CNC, JKA, LDC].

Diagnosis.

Sympistis eleaner (Figs 1, 2) is most similar in appearance to S. induta (Harvey) (Figs 3, 4) but the distribution of the two do not overlap, with S. induta restricted to Texas. Sympistis eleaner is not likely to be confused with any other species Sympistis besides S. induta . There is a set of rather subtle, but distinct, pattern elements that distinguish the two species: S. eleaner has an overall streakier appearance, especially in the male hindwing; the forewing antemedial line takes a distinctive 110° turn inward at the costa that is more irregular in S. induta ; there is a lighter patch near the anal angle of the hindwing (between Cu2 and A2) that is not present in S. induta ; the male of S. induta has a much “cleaner” hindwing with a less irregular PM line; the female forewing is broader than that of the male in S. eleaner , but female induta have narrower forewings than the males.

The male genitalia of S. eleaner (Figs 9, 10) differ from those of S. induta and other species in the badistriga species-group by the shorter, broader valve that has a nearly linear costal margin. In females, the combination of a pear-shaped corpus bursae with a relatively short ductus bursae is unique.

Description. Forewing pattern typical of the Sympistis badistriga species-group, beige, dark markings limited to sinuous antemedial and postmedial lines. Male and female similar, females slightly larger and darker, especially the distal hindwing (Figs 1, 2). Head. Labial palpus, frons, head vertex scales light gray beige and scattered dark brown; female darker with more scattered black scales; antenna simple, unscaled; eye without interfacetal setae; labial palpus with heavily scaled basal and second segments, second segment mottled prominently dark brown; third segment very short, stout. Thorax. Vestiture grayish beige, concolourous with abdomen and forewing ground; black prothoracic collar pronounced in male, incomplete medially in female; collar with posterior linear extension onto mesonotum in male; leading edge of mesonotum (directly behind collar) with fringe of hair-like, dark brown scales, making collar appear more pronounced. Legs with distal end of femur with black scaling (at “knee”); proximal 2/3 of tarsomeres 1 and 2 on all legs black, proximal ½ on remaining tarsomeres black; paired tibial spurs, scaled black, on meso- and metathoracic legs; foretibial spur present but concolorous with rest of thorax; stout apical spur of foretibia typical of many Sympistis absent. Forewing. Male forewing length 13.7-14.0 mm, female 14.9 mm. Dorsal forewing ground color grayish beige with dusting of black scales, most concentrated along veins; basal dash extending to postmedial line along posterior edge of discal cell; antemedial line with distinct bend at costa (approx. 110°); posteriorly angled slightly outward to anal edge; postmedial line with typical Sympistis -bulge from end of basal to costa; costa distad of postmedial line with alternating light beige spots at radial veins and dark gray dashes between veins; fringe with alternating beige at veins and dark grayish tan between; distal half of ventral forewing cream beige to cream (especially in anal area); scattered dark brown scales, denser toward both costa and apex, costa and fringe checkered as above; faint postmedial line short, from radial veins to M2; abundant tan hair-like scales in discal cell. Hindwing. Dorsum cream to cream beige basally and along anal; outer fringe scales two-toned, beige basally, cream terminally (no checkering); postmedial line sinuous and discontinuous, separate from outer band in male, fused in female; gray outer band also discontinuous, darkest along veins, lightest at anal angle between Cu and A2. Venter basal 2/3 cream beige to cream; outer band darker distally to smooth curving unbroken PM line (from costa to Cu1); small patch of dark brown scales demarcate small discal spot on both fore- and hindwing ventrum. Abdomen. Vestiture grayish beige; female with more extensive dark scaling; black scales concentrated in two ventrolateral dark lines running length of abdomen; male with basal abdominal coremata, levers and associated pocket well-developed; Stobbe’s gland well-developed; female abdomen unmodified. Male genitalia. Valve elongate with distal 2/3 somewhat rounded-quadrate, with costal edge nearly linear and distal margin only slightly convex; clasper slightly bulbous with claw-like apex, curving mesad slightly; corona a single row of robust but deciduous spine-like setae; juxta poorly differentiated; uncus curved moderately ventrad, tapering rather abruptly at apex, with small, nearly caudad-directed apical spine; saccus shaped as somewhat convex/curved V; phallus cylindrical and slightly decurved ventrad; distal half slightly narrower than basal portion, length 5.3 × that of diameter; vesica produced at 90° right dorso-laterad, with four spine fields and a terminal cornutus (Fig. 10). Female genitalia. Papillae anales slender with somewhat rounded distal margin; distally with short sparse setae and a row of subterminal, lateral hook-like spines forming a corona; posterior apophysis long and slender, 3 × length of sclerotized portion of A8; posterior apophysis 2.5 × length of sclerotized portion of A8; lamella antevaginalis weakly sclerotized and unmodified; ostium forming a rounded cone, slightly longer than wide; appendix bursae pear shaped, with ductus seminalis originating at anterior end and directed caudad; corpus bursae reduced to a small, polyp-like vesicle attached to right side of main bursa chamber.

Etymology.

The species is named in honor of the mother of JKA, Eleaner Ruth Adams. She continuously encouraged JKA in studying Lepidoptera from a very young age and participated with JKA in many moth outings during her life.

Biology and Distribution.

Nothing is known about the early stages of S. eleaner . Larval hosts for related species in the badistriga species-group are known or thought to be primarily species in the honeysuckle family ( Caprifoliaceae ); S. badistriga (Grote) feeds on Lonicera Linnaeus and S. stabilis (Smith) feeds on Symphoricarpos Duhamel, respectively ( Crumb 1956). At least three species of Caprifoliaceae are known to occur on the island: Sambucus simpsonii Rehder, Lonicera japonica Thunberg, and L. sempervirens Linnaeus ( Chalmers 1997). The recorded flight time for the species is from April 21 to May 10; it likely flies a bit earlier and/or later than this date range depending on the year. Sympistis eleaner is probably univoltine like other members of the species group, and since it has not been collected during any other season despite intensive sampling, although the fact that it took five years to find the moth in the first place does not rule out the possibility of later-flying generations.

The type locality is a large, stabilized dune 0.4 km from the Atlantic shoreline. It is vegetated sparsely (most notably by Cenchrus tribuloides Linnaeus ( Poaceae ) and short Smilax Linnaeus ( Smilacaceae )) and surrounded by southern red cedar ( Juniperus silicicola (Small) Bailey, Cupressaceae ), various pines ( Pinus Linnaeus, Pinaceae ) and scrub oaks ( Quercus Linnaeus, Fagaceae ). The known distribution of Sympistis eleaner is currently defined by the type series. These localities are within a 2.8 km section along the Autobahn/Beach Road on the south side of Sapelo Island. It has been found in dune, grassy (surrounded by forest at the greenhouse) and forested habitats. It could potentially occur on other barrier islands along the southeastern United States coast, but extensive surveys may need to be done to find it considering the species is rarely and only recently collected on Sapelo Island.

Molecular variation.

DNA barcode sequence (voucher # CNCLEP11937) of the holotype male formed a unique Barcode Index Number (BOLD:ADG0355), differing by a minimum of 5% from all other North American Sympistis species, but consistently clustering with species of the badistriga and infixa species-groups.

Discussion.

Sympistis is the second-largest genus of noctuids in North America, with 178 species ( Pohl et al. 2016). It is most diverse in xeric habitats of the western United States. Just four species have been recorded previously from Georgia: S. badistriga , S. infixa (Walker), S. perscripta ( Guenée), and S. chionanthi (Smith). The genus was reviewed by Troubridge (2008), who described many new species (all western), and synonymized eight genera under a revised concept of Sympistis . Troubridge (2008) recognized 19 species-groups, defined largely by genitalic morphology, that incorporate about half of the known species.

The forewing traits of S. eleaner , with a simple, streaky pattern, dark basal dash and evenly sinuate antemedial and postmedial lines, are shared with members of the infixa and figurata species-groups. Although these groups are externally similar, they differ significantly in morphology. A subgroup of the S. badistriga species-group ( Troubridge 2008) comprised of S. badistriga , S. apposita (Barnes and McDunnough), S. stabilis , S. induta , S. rayata (Smith) and S. tenuistriga (McDunnough) is defined by absence of the stout foretibial spine, presence of a tiny, vestigial corpus bursae, and the origin of the ductus seminalis from the anterior appendix bursae. Sympistis eleaner exhibits all of these synapomorphies, placing it securely within the S. badistriga species-group. However, neither its barcode nor morphological features suggest a close relationship to any particular species, seemingly representing a distinct and likely relict eastern member within the group with a long, separate evolutionary history. This underscores the need for a phylogenetic framework for this very large, morphologically and ecologically diverse genus.