Pacifimusotima Ko & Solis, 2024

Ko, Jae-Ho, Solis, M. Alma, Lees, David C. & Albert, Austin, 2024, Pacifimusotima Ko & Solis, new genus and species of the Musotiminae (Lepidoptera: Crambidae) from the Federated States of Micronesia, including two newly combined species, Zootaxa 5497 (1), pp. 111-122 : 112-114

Genus Pacifimusotima Ko & Solis , gen. nov.

TS: Pacifimusotima kosrena Ko & Solis , sp. nov. Gender: feminine.

Diagnosis. The new genus ( Figs. 1–3, 7 , 9–20 ) is similar to Aeolopetra Meyrick, 1934 ( Yen 1996: p. 293–299, and see figs. 1–8), in its general large size with a forewing length greater than 1 cm, but can be distinguished by the following characteristics: ground color of the wings is white, but whitish-ocherous in Aeolopetra ; termen of the wings nearly straight, but sinuous in Aeolopetra ; forewing has a striking brown W-shaped marking that is lacking in Aeolopetra . In the venation of the forewing, R 1, R 2, and R 3 originate before the upper angle of the discal cell but they originate in the upper angle in Aeolopetra ; CuA 1 originates before the lower angle of the discal cell, but originates in the lower angle in Aeolopetra ; A 3 is absent, but present in Aeolopetra . In the venation of the hindwing, M 3 and CuA 1 are independent, but originate in the lower angle of the discal cell in Aeoloptera; CuP fades at about from base to 1/3 of CuP, but is complete in Aeolopetra ; A3 is present but absent in Aeolopetra . In the genitalia, the uncus and the gnathos in this genus are shorter than those of Aeolopetra ; the valva is nearly subspatulate and ovate in Aeolopetra . The female genitalia of Aeolopetra are unknown and therefore cannot be compared.

Description. Adult ( Figs.1–3,7 , 9–13 ).Head covered with white scales; antennae prismatic,laterally compressed; ocellus and chaetosemata absent; labial palpus three-segmented, upturned; maxillary palpus three-segmented, very short; proboscis well−developed. Thorax covered with white mixed brown scales. Forewing rhomboid; basal and median band present; postmedial area with W-shaped marking; costal margin nearly straight; apex weakly pointed; termen rounded, obtuse angled from M 2 to M 3; dorsum nearly straight; frenulum hook a short set of hooked setae basally. Hindwing fan–shaped; costal margin rather straight; apex weakly hooked; termen rounded, obtuse angled from M 2 to CuA 1; dorsum rather rounded; frenulum one in male, two or more in female. Venation: forewing with 12 veins: Sc free; R 1 free, faded from 1/3 of R 1 to costal margin; R 2 free; R 3 and R 4 stalked for most of length; R 2 and R 3 +R 4 approximated; R 5 free, from upper angle of discal cell; M 1 free; M 2 and M 3 approximated at base, from lower angle of discal cell; CuA 1 and CuA 2 free; 1A+2A free; discal cell open, 1/2 length of forewing. Hindwing with 10 veins: Sc+R 1 and Rs stalked for 1/2 length of Rs; M 1 free; M 2 free, faded from 1/2 of M 2 to base; M 3 and CuA 1 free; CuA 2 free; CuP free, faded from 1/3 of CuP to base; 1A+2A and 3A free; discal cell absent. Abdomen with white scales.

Tympanal organs ( Figs. 19–20 ). Tympanal cases (=bulla tympani, caisses tympaniques) enlarged, broadly separated, and areas on either side of the elongated pons tympani slightly sclerotized, tympanic frame (=fornix tympani, cadre tympanique) and ramus tympani highly sclerotized, with a sclerotized medial line extending posteriorly, and praecinctorium a single long lobe.

Male genitalia ( Figs. 14–16 ). Hood-like uncus and gnathos cheliform; gnathos smooth, not dentate; tegumen almost same length as vinculum; valva nearly subspatulate; juxta broad, slightly sclerotized; saccus U-shaped; phallus cylindrical, coecum slightly over two times the length of the distal area beyond the ductus ejaculatorius, hook or club-shaped cornuti present.

Female genitalia ( Figs. 17–18 ). Anterior apophyses and posterior apophyses long of almost equal size; ostium tube-shaped, membranous; antrum weakly sclerotized; ductus bursae narrow, membranous; corpus bursae ovoid, without signum.

Distribution. Micronesia (Chuuk, Kosrae), Samoa, Fiji, Papua New Guinea, Borneo.

Etymology. The generic name is a combination of the prefix " Pacifi," from "Pacific Ocean," and the suffix " Musotima ," from the type genus " Musotima ". Gender is feminine.

Remarks. We place Pacifimusotima in Musotiminae based on the laterally compressed antennae, in the forewing venation R 2 is stalked or approximated with R 3+4, and the tympanal cases are enlarged, although it lacks a reduced coecum in the phallus that is found in most musotimines (it is three times the length of the distal area beyond the ductus ejaculatorius) ( Minet 1982, 1985; Solis et al. 2005a, b; Yen 1996; Yen et al. 2004).

The genus is exclusively found on islands in the Pacific Ocean, with its most easily recognizable characteristic being the W-shaped marking on the postmedial area of the white forewing. We searched for species resembling the new genus within Musotiminae , but especially in the genus Parthenodes where the undescribed species had been placed previously by E. G. Munroe and E. L. Martin (see label data below). An examination of all species within Parthenodes revealed that the species P. eugethes and P. rectangulalis were congeneric with the new genus described here.Therefore, we transfer Parthenodes eugethes comb. nov. and P. rectangulalis comb. nov. to the genus Pacifimusotima , newly described in this study. Additionally, species labeled Musotima sp. 6 and sp. 17 and figured in the recently published volume of Bornean moths by Whitaker et al. (2023), have the characteristic W-shaped marking on the postmedial area on a white forewing and upon examination they will probably be found to belong in this new genus. Upon preliminary examination of type specimen images of species in Parthenodes , we noted that they are not congeneric with the type species, P. hydrocampalis Guenée, 1854 , described from two syntypes (labelled “co-types”), one male and one female, from Cayenne, French Guiana ( Fig. 4 ) (lectotype to be designated in a future paper). We figure type specimens of some of the other species, P. parallelalis Hampson, 1917 ( Fig. 5 ) from Peru (not to be confused with Paracymoriza parallelalis Sauber in Semper, 1902, ( Acentropinae ) described from the Philippines), and from India P. bisangulata (Hampson, 1896) ( Fig. 6 ) and P. nigriplaga (Swinhoe, 1894) ( Fig. 8 ). They will require careful examination and study for their placement in a future paper.

Figures

FIGURES 1−8. Adults of Pacifimusotima and Parthenodes spp. 1a. Pacifimusotima kosrena Ko & Solis, sp. nov., holotype, male, Kosrae, Micronesia; 1b. Pacifimusotima kosrena Ko & Solis, sp. nov., paratype, female, Kosrae, Micronesia; 2. Pacifimusotima rectangulalis comb. nov., male, Chuuk, Micronesia, USNMENT01894106, USNM genitalia slide no. 116393; 3. Pacifimusotima eugethes, comb. nov., male, Apia, Samoa, USNMENT01894135; 4. Parthenodes hydrocampalis (co-type), NHMUK015666233; 5. Parthenodes parallelalis (= P. paralleloidalis), holotype, Chanchamayo, Peru, NHMUK015666232; 6. Parthenodes bisangulata, holotype, Sikkim, India, NHMUK013699575; 7. Pacifimusotima rectangulalis, comb. nov., syntype, Ekeikei, Papua New Guinea, NHMUK010919370; 8. Parthenodes nigriplaga, syntype, Khasia Hill, Meghalaya, India, NHMUK013699595.

FIGURES 9–10. Head of Pacifimusotima kosrena Ko & Solis, sp. nov. 9. Dorsal view; 10. Lateral view.

FIGURES 11–13. Palpi and wing venation of Pacifimusotima kosrena Ko & Solis, sp. nov. 11. Labial palpus; 12. Maxillary palpus; 13. Wing venation.

FIGURES 14−16. Male genitalia of Pacifimusotima spp. 14a. P. kosrena Ko & Solis, sp. nov., holotype, DIC-051; 14b. P. kosrena Ko & Solis, sp. nov., paratype, DIC-101; 15. P. rectangulalis, comb. nov., USNMENT01994059, USNM genitalia slide no. 116394; 16. P. eugethes, comb. nov., USNMENT01894141, USNM genitalia slide no. 116391.

FIGURES 17−20. Female genitalia and tympanal organs of Pacifimusotima spp. 17. P. kosrena Ko & Solis, sp. nov., female genitalia, paratype, DIC-052; 18. P. eugethes comb. nov., female genitalia, USNMENT01894129, USNM genitalia slide no. 116392; 19. P. kosrena Ko & Solis, sp. nov., tympanal organ, paratype, DIC-101; 20. P. eugethes, comb. nov., tympanal organ, USNMENT01894141, USNM genitalia slide no. 116391.