Sacada chaehomensis Pellinen & Zahiri, 2020

Pellinen, Markku J., Zahiri, Reza & Sihvonen, Pasi, 2020, A new species of Sacada Walker, 1862 from Thailand (Lepidoptera, Pyralidae, Pyralinae), Evolutionary Systematics 4 (2), pp. 71-77 : 71

Sacada chaehomensis Pellinen & Zahiri sp. nov. Figs 4 , 7 , 8

Type material.

Holotype ♂ (label data given verbatim, “/” indicates new line, “;” indicates new label]: Thailand Lampang/ Chae Hom 340 M/ 18°43'19"N, 99°33'11"E / 23.5.2020/ Leg. Pellinen, Markku [white label]; MJPT0020 [green label, indicates M. J. Pellinen DNA tissue sample]; ZMH-DNA0199 [indicates Universität Hamburg DNA process number]; 0146 [pink label, indicates M. J. Pellinen photograph number]; Pasi Sihvonen,/prep. number 2828 [blue label]; http://id.luomus.fi/GBT.1; Sacada / chaehomensis / Pellinen & Zahiri/ HOLOTYPE [red label] (in coll. Finnish Museum of Natural History, Helsinki, Finland).

Other material examined.

Only holotype male is known.

Diagnosis.

Sacada chaehomensis sp. nov. is morphologically similar to S. dzonguensis Singh, Kirti & Ranjan, 2020 and S. umtasorensis Singh, Kirti & Ranjan, 2020. Diagnostic male characters of these three species are indicated on Figs 2 - 7 (females of these three species are unknown). Forewing postmedial line is straight on costa and medial line is straight in S. chaehomensis sp. nov. (postmedial line curved and medial line angled in S. dzonguensis ; postmedial line straight and medial line angled in S. umtasorensis ). With regard to diagnostic male genitalia characters, see Figs 5-7 .

Description.

Description is based on male, female is unknown. Wingspan 40 mm. Antennae with basal two thirds bipectinate, apical third fasciculate. Head, thorax and abdomen rufous. Tegula with iridescent scales of purplish-grey hue. Labial palps short. Base of proboscis covered densely with scales. Fore- and midleg tibia with massive hair tuft, spur formula of legs 0-2-4. Forewing narrow, reddish brown, medial, postmedial and terminal lines dry straw colored (fuscous). Medial line angled, postmedial line straight, forming triangular area on midwing. Terminal line narrow, fringes concolorous with wings. Hind wing wide, grey, weakly rufous near margin, veins darker. Terminal line fuscous, fringes concolorous with wings. Forewing underside rufous grey-brown, medially darker and inner margin pale. Hindwing underside rufous grey-brown on costa, otherwise paler. Postmedial line weakly visible on both wings. Tympanal organs large, semi-circular, fornix tympani separate but connected via narrow sclerotised ridge (in Fig. 7c metathorax sclerotisations and metafurca are visible between tympanal organs). Abdominal segments weakly sclerotised, 8th tergite with two posterior lobes, 8th sternite with round posterior margin.

Male genitalia. Uncus hood-shaped, curved, densely setose, with rounded lobes basolaterally. Gnathos sclerotised, arms forming narrow bands, arms fused medially forming upwards directed weakly dentate hook; basolateral parts curved inwards, lobe-shaped. Tegumen formed of two narrow plates. Valva simple, setose, pointing weakly outwards; costa straight. Transtilla large, sclerotised, plate-like, with distinct elongated, upwards directed projection medially, its apex blunt. Juxta broad, weakly constricted laterally, anterior margin even, posterior margin with two heavily sclerotised arms bearing few spikes. Vinculum narrow. Saccus elongated, apex round. Aedeagus stout and weakly undulating, caecum round, apical apodeme ventrally with small group of dentate spikes. Vesica large, simple, without distinct diverticula, basal part wider, apical part narrow and weakly curved; base covered with minute spikes, followed by minute sclerotisations, those become fewer towards vesica apex.

Etymology.

The species is named after its type locality, Chae Hom, in Lampang province, Thailand.

Biology.

The single known male was collected in May 2020 at 340 m altitude; it was attracted to light in forest with diverse tree species, interspersed with small vegetable plantations (Fig. 9 ). Immature stages are unknown.

Distribution.

The only specimen was collected in Lampang (Chae Hom) in northern Thailand.

Barcode analysis.

A 642 bp barcode of Sacada chaehomensis sp. nov. was submitted to the identification engine on BOLD. Genetically nearest neighbors are unidentified pyralids from Malaysia, Sabah (North of Borneo) with a minimum divergence of 6.17% and another from Malaysia, North of Kuala Lumpur with 6.50%. The other pre-existing data for Sacada on BOLD were Sacada ragonotalis (6.54%) and Sacada albioculalis (8.93%), thus indicating that the unidentified pyralids may be Sacada sp. The species morphologically most similar (i.e., S. dzonguensis and S. umtasorensis ) to the new taxon lacked representations on the BOLD DNA library. The tree topology generated by the BI analysis (Fig. 10 ) was very similar to the NJ-tree confirming the association (PP = 0.87) of the new species (ZMH199) with the sister pair of unidentified pyralids from Malaysia, Borneo (LPMLY526-14+ LPMLY208-14) and Malaysia, North of Kuala Lumpur (LPMAL244-14+LEPML271-13). The relationships between analyzed Sacada must be treated with caution, because those are based on short DNA barcode sequences only, and are likely to change with addition of more molecular data and expanding taxon sampling.

Figures

Figure 8. Descaled male abdomen of Sacada chaehomensis sp. nov. (holotype) 8 a abdomen 8 b 8 th tergite 8 c tympanal organs (slide Sihvonen 2828).

Figure 9. Collecting site of Sacada chaehomensis sp. nov. Thailand, Lampang, Chae Hom, 8.9.2013, photo by Markku Pellinen.

Figure 10. The Bayesian tree from analysis of the COI 5 P sequences of Sacada chaehomensis sp. nov. and 17 public Sacada DNA sequences. The nodes are scored by posterior probabilities (PP).

Figures 2 - 4. Adults of Sacada spp. with diagnostic characters indicated 2 S. dzonguensis Singh, Kirti & Ranjan (male) 3 S. umtasorensis Singh, Kirti & Ranjan (male) 4 a S. chaehomensis sp. nov. (male, dorsal view) 4 b S. chaehomensis sp. nov. (male, ventral view). Figs 2, 3 based on Singh et al. (2020), used with permission.

Figures 5 - 7. Male genitalia of Sacada with diagnostic characters indicated 5 S. dzonguensis Singh, Kirti & Ranjan (holotype) 5 a aedeagus 5 b genitalia 6 S. umtasorensis Singh, Kirti & Ranjan (holotype) 6 a aedeagus 6 b genitalia 7 S. chaehomensis sp. nov. (holotype, slide Sihvonen 2828) 7 a aedeagus with vesica everted 7 b aedeagus 7 c genitalia. Figs 5, 6 based on Singh et al. (2020), used with permission.