On the taxonomy of the genus Sacada Walker, 1862 from India, with descriptions of a new genus and two new species (Pyralinae, Pyralidae, Lepidoptera)

Abstract Two new species, Sacada dzonguensis N. Singh, Kirti & Ranjan, sp. nov. and S. umtasorensis N. Singh, Kirti & Ranjan, sp. nov., are described from India. Additionally, seven species of the genus Sacada Walker, 1862 are redescribed. A new genus, Pseudosacada N. Singh, Kirti & Ranjan, gen. nov., is described to accommodate Paravetta flexuosa Snellen, 1890 (presently in Sacada). A new combination is established: Pseudosacada flexuosa (Snellen, 1890), comb. nov. Morphologically, the new genus resembles the genus Sacada and can only be diagnosed by the male genitalia. The diagnostic differences are discussed and illustrated along with adults and external male genitalia of related taxa. A world checklist and a key to the Oriental and Australasian species are provided.


Introduction
The genus Sacada Walker, 1862 is a member of the family Pyralidae Latreille, 1809 and subfamily Pyralinae Latreille, 1809. It was established by monotypy for S. decora Walker, 1862from Sarawak, Borneo. Hampson (1896 broadly discussed the nomenclature of this genus, synonymised several genera (i.e. Sybrida Walker, 1865, Paravetta Moore, 1865, Danaka Moore, 1879, and Xestula Snellen, 1885 with Sacada and studied nine species, which he divided into two distinct sections on the basis of male antennal characters: one group with bipectinate antennae with long branches along three-quarters of their length, and the other group with antennae serrate and fasciculate. Recently, Leraut (2013) revised the generic diagnosis of Sacada by including external genital attributes. The genus is known by 41 species, including 22 from the Oriental region and 10 from India (Nuss et al. 2003(Nuss et al. -2020. Herein, two new species are described from India: Sacada dzonguensis N. Singh, Kirti & Ranjan, sp. nov. (Sikkim) and S. umtasorensis N. Singh, Kirti & Ranjan, sp. nov. (Meghalaya). In addition, the morphotaxonomy of seven Indian species of Sacada Walker, 1862 is studied. A new genus, Pseudosacada N. Singh, Kirti & Ranjan, gen. nov., is erected to accommodate Paravetta flexuosa Snellen, 1890 (presently in Sacada), and a new combination is established: Pseudosacada flexuosa (Snellen, 1890), comb. nov. Morphologically, the new genus resembles species of Sacada and can only be diagnosed by the male genitalia. The diagnostic differences are discussed and illustrated along with adults and external male genitalia of related taxa. A world checklist and identification key to the Oriental (23 species) and Australasian (four species) species are also provided. The distribution of species is updated from the publications by Hampson (1896), Yamanaka (1995Yamanaka ( , 1998, Nuss et al. (2003Nuss et al. ( -2020, Bae et al. (2008), and Sutton et al. (2015) .

Material and methods
Adult moths were collected using vertical sheet light traps fitted at various localities of India. Collected specimens were euthanized with ethyl acetate vapours in killing jars. The specimens were pinned, stretched, and processed as per standard techniques in lepidopterology. Adult moths were photographed using a Canon EOS 1300D digital SLR camera. The detailed microphotography of external male genitalia was performed under a Leica M165C stereomicroscope attached with a Leica MC190HD camera enabled with a Leica Application Suite. The examined specimens are deposited in the National Zoological Collections, Lepidoptera Section, Zoological Survey of India (ZSI), Kolkata, India. The collection abbreviations are according to Evenhuis (2020).
Type species. Sacada decora Walker, 1862. Diagnostic characters. Mostly dark-coloured moths with a slightly variable wing pattern; male antennae typically pectinate (ciliate and toothed in some species). In addition to the narrow forewing with angular edge and the sexual dimorphism with the female being much larger than the male, the genus Sacada is well defined by a number of characters: long legs with tufts of scales, some of which are filiform; thorax with patagia having prominent scales, ending with two brushes; male genitalia with uncus hooded; free valves without process; transtilla modified into elaborate sclerotized structure; juxta well developed; female genitalia with wide anal papillae; very short eighth segment; very short ductus bursae prolonged by a long, ovoid corpus bursae with sclerotisations (Leraut 2013).
Type material examined. Lectotype ( Fig. 2 Description. Male, wingspan 24 mm (Fig. 3). Adult dark purplish fuscous. Forewing with a dark rufous rectangular patch near base, touching antemedial line, which is highly angled in interno-median interspace; postmedial line pale, sinuous, nearly orthogonal from costa to vein M 2 , then very oblique to inner margin; area between antemedial and postmedial line paler; discocellular with two specks, outer one darker. Hindwing pale fuscous, submarginal line pale, slightly waved, crossed by a dark streak at vein Cu 1 . Cilia of both wings ochreous, with two black lines passing through them. Male genitalia (Figs 21,22). Uncus broad with flaps on lateral side; gnathos with tip hooked; valva simple, without any process; tegumen simple; transtilla broad and sclerotised, bifid process originating medially; juxta broad with a vertical incision from tip to base, forming two arms, spined apically; saccus U-shaped; vesica membranous with fine scobination, without any cornuti.
Diagnosis. Among the Sacada species reported from India, S. discinota is externally similar to S. sikkima and S. constrictalis due to the highly angled antemedial and postmedial lines, but it is distinct from both of these congeners by its paler hindwings.

Sacada unilinealis
Description. Male, wingspan 32-34 mm (Figs 7, 8). Adult pale rufous, speckled with fuscous; forewing pale brownish pink; basal and apical area of costa rufous; forewing with two black specks (lower one large, giving appearance of a spot) conjoined by a narrow bar; traces of evenly curved postmedial line, with area beyond it darker. Hindwing pale, with faint traces of a curved submarginal line. Cilia of both wings dark rufous. Blackish fringe of hair on fore and mid tibiae. Male genitalia (Figs 25,26) with uncus short, broad with flaps on lateral side; gnathos well developed reaching to uncus, tip hooked; valva broad, simple, without any process; tegumen simple; transtilla with a sclerotised process arising medially; juxta double, each broad at base, apically pointed and sclerotised, concave on inner edge, convex on outer edge; saccus long, broadly U-shaped; vesica membranous with fine scobination, without any cornuti.
Diagnosis. Sacada unilinealis is an unmistakable species due to the weak markings and almost uniform colour of the fore and hindwings.
Type material examined. Holotype (Fig. 8  Description. Male, wingspan 36 mm (Fig. 10). Rufous brown. Forewing with a medial fuscous line outwardly oblique from costa to vein Cu 2 , slightly indented in cell, at Cu 2 rounded inwardly to meet inner margin; a dark streak on discocellular; a postmedial fuscous line, inwardly oblique from radial veins; inner area of antemedial and outer area of postmedial lines bordered with ochreous scales; a broad fuscous band beyond postmedial line, veins on it paler; inner area dark brownish; a fine marginal line, cilia brownish; underside rufous with inner area ochreous. Hindwing pale fuscous with rufous tinge; traces of diffuse, postmedial fuscous line; a fine marginal line present; underside rufous. Male genitalia (Figs 27,28): uncus hooded with baso-lateral flaps; gnathos curved distally, tip pointed and hooked, broadened below tip; valva simple; transtilla broad and curved distally; juxta broad at base, mediolateral area constricted, bifid apically: both arms (spikes) bearing small spines; vinculum U-shaped; aedeagus apex with multiple rows of small spines; base of vesica densely scobinated and the scobination gradually becomes sparse towards distal end.
Diagnosis. Sacada dzonguensis sp. nov. is most similar to S. inordinata (Fig. 9), but the forewing has the antemedial and postmedial lines clearly separated, and there is a broad fuscous band beyond the postmedial line, whereas in S. inordinata both lines are fused from vein Cu 2 to the inner margin, and the postmedial fuscous band is absent (but with traces of ferruginous).
Etymology. The species is named after its type locality, Dzongu, Sikkim, India. Description. Male, wingspan 30 mm (Fig. 11). Rufous brown. Forewing with a sinuous medial fuscous line outwardly oblique from costa to vein Cu 2 , then broadly and inwardly rounded to meet inner margin; a band of paler scales on discocellular; postmedial fuscous line, slightly curved, inwardly oblique from costa to inner margin; inner area of medial line and outer area of postmedial line bordered with ochreous scales; a broad ferruginous band beyond postmedial line; a fine marginal line, cilia brownish; underside rufous with inner area ochreous. Hindwing pale fuscous with rufous tinge; traces of diffused, postmedial fuscous line; a fine marginal line present; underside rufous. Male genitalia (Figs 29,30): uncus hooded with baso-lateral flaps; gnathos curved distally, hooked, tip pointed, broadened before tip; valva simple; transtilla broad with two apical, small thumb-like processes; juxta narrow, mediolateral area constricted, bifid apically with both the arms bearing spikes; vinculum U-shaped; aedeagus apex with single row of small spines; base of vesica densely scobinated and the scobination gradually becomes sparse towards apex. Diagnosis. Sacada umtasorensis sp. nov., distributed in Meghalaya is most closely similar to its allopatric relative S. dzonguensis sp. nov., (distributed in Sikkim) (Fig. 10), but it is distinct by the oblique postmedial line from costa to inner margin, whereas in S. dzonguensis, the postmedial line is straight from the costa to the radial vein and then oblique to the inner margin. In the male genitalia of S. umtasorensis (Figs 29, 30), the juxta is narrow with the two apical lobes exhibiting more spines, and the aedeagus apex has a single row of small spines, whereas in S. dzonguensis (Figs 27, 28), the juxta is broad, the apical lobes have fewer spines, and the aedeagus apex exhibits multiple rows of small spines. Description. Male, wingspan 32 mm (Figs 12, 13). Pale rufous. Forewing speckled fuscous; a dark brownish basal spot; antemedial line smoothly curved; a speck on discocellular; postmedial line slightly curved below costa, then oblique to inner margin, some fuscous suffusion beyond it; cilia dark at tips; underside ochreous with rufous suffusion on basal half of costa, curved postmedial line present. Hindwing pale with indistinct, evenly curved postmedial line, crossed by a rufous streak on vein Cu 2 . Underside with curved postmedial line. Male genitalia (Figs 31,32). Uncus broad with a fold on lateral side; gnathos well developed, tip hooked; valva simple, without any process; tegumen broad; transtilla broad, forming inverted omega (ω) shape; juxta short and broad, slightly constricted at apex; saccus long; vinculum U-shaped; aedeagus long, vesica membranous with fine scobination, cornuti absent. Diagnosis. Sacada pallescens is unmistakable among the species studied due to the smoothly curved antemedial line (highly angled in other Indian species, except in S. unilinealis where it is absent) and hindwing which has a prominent rufous streak on vein Cu 2 .
Type material examined. Lectotype (Fig. 13) Description. Male, wingspan 25.4 mm (Fig. 14). Rosy red; forewing with antemedial line outwardly oblique, broadly and inwardly rounded at vein Cu 2 to meet inner margin, where a black patch is present towards its inner edge; two black discal spots; an inwardly oblique, paler postmedial line followed by a broad band of fuscous scales, which is diffusing towards termen. Hindwing paler, a diffused postmedial line present. Diagnosis. Because of the smoothly curved postmedial line (not strongly angled), S. decora is externally similar to S. inordinata, S. dzonguensis, S. umtasorensis, and S. pallescens, but it differs from three of these four species having its hindwing paler, and from S. pallescens in having the antemedial line outwardly oblique and broadly and inwardly rounded at vein Cu 2 . Diagnosis. The new genus is morphologically most similar to the genus Sacada and can only be diagnosed on the basis of external male genitalia. In male genitalia, the uncus is broader at base, apically bifid with a shallow constriction. There are two strongly sclerotised processes arising from the latero-medial region of the uncus. The gnathos is long, reaching beyond the uncus, and with its apex having a small hook. The valva is simple and membranous, without any process. The transtilla is broad and with both the edges bearing scorpion's "pedipalp chela"-like sclerotised process. In Sacada, the uncus is hooded, lateral structures are simple, flap-like, and without any horn-like process; the gnathos is short and hardly reaches the hood of the uncus; the valva is thicker; and the transtilla is simple.
Remarks. The type species of the new genus was originally placed in Paravetta (type species Paravetta discinota Moore, 1865). Paravetta is now a synonym of Sacada. However, P. flexuosa is generically distinct from Sacada decora, the type species of Sacada, and therefore a new genus is erected here.
Etymology. The genus is named for its morphological resemblance to some species of Sacada. The gender is feminine.

TD. Lectotype in NHMUK.
Description. Male, wingspan 30 mm (Figs 15-18). Adult dark chocolate brown with fuscous and purple tinge; antennae bipectinate up to one-third of the length, apically simple; abdomen pale brownish; anal tufts rather strong; forewing with sub-basal, oblique purple patch below cell; antemedial line outwardly oblique from costa to vein Cu 2 , then rounded inward to meet inner margin, a small indention present in cell; postmedial line inwardly oblique, former inwardly and later outwardly bordered with ochreous scales; area between both lines distinctly differently coloured then rest of wing, an elongate spot on discocellular; on outer side of postmedial line, a roughly rectangular ochreous golden patch present from sub-costa to vein R 5 , veins on it dark. Hindwing ochreous brown with a curved postmedial line; outer area darker; underside paler; cilia as ground colour with fuscous basally. Hind tibia with two pairs of unequal tibial spurs covered with dark rufous scales, tip of each spur covered with whitish scales, one separate bunch of long rufous scales present. Male genitalia (Figs 33-40

Discussion
After the description of two new Sacada species and the transfer of one species to Pseudosacada gen. nov., the genus Sacada now comprises 42 species worldwide, including 23 from the Oriental region and 11 from India. With 13 Sacada species, the Afrotropical region is the next most diverse region for this genus, and a future systematic revision should focus on these species. Apart from this, the Australasian region, with four species (included in the identification key) and the East Palaearctic region with two species (S. fasciata, S. misakiensis) need study to investigate the correct placement of Sacada from these regions based on features of genitalia morphology.