Neoperla philippinensis Pelingen, 2024

Pelingen, Arthien Lovell, 2024, Description of Neoperla philippinensis sp. nov. confirmed using integrative taxonomy and some notes on Neoperla oculata Banks, 1924 (Plecoptera: Perlidae), Zootaxa 5399 (5), pp. 570-578 : 571-575

Neoperla philippinensis Pelingen sp. nov.

https://zoobank.org/ A1F061BA-25B9-43C8-AFA9-9EDD37F8455D

Material examined. Holotype: 1 ♁ adult ( PL150 ); PHILIPPINES: Mindanao, Zamboanga; Pasonanca [899]; ca. 6°57”N, 122°04’E; ca. 50 m a.s.l.; 13 January 2019; leg. Siglos; NMP in ethanol. Paratype: 1 ♀ adult ( PL151 ); PHILIPPINES: Mindanao, Zamboanga; Pasonanca [899]; ca. 6°57”N, 122°04’E; ca. 50 m a.s.l.; 13 January 2019; leg. Siglos; NMP in ethanol

Description. Imago ( Fig. 1A, 3): Small sized species. Forewing length of male: 10.0 mm, female: 12.0 mm. General color pale brownish yellow. Ocelli large, separated by a small gap. Head wider than pronotum, pale yellow, mottlings pale brown. M-line clearly visible. Antenna and palpi color same as head. Pronotum anterior corners angular, posterior corners curved, ground color same as head, has a median light brown stripe, area adjacent to the median line are paler; sublaterally, is a broad area of darker rugose pigmentation. Meso- and metanotum slightly darker than pronotum. Legs light brown, proportion 1.0: 1.2: 1.4, tibia darker than femur. Wings hyaline, veins brown.

Male terminalia ( Fig. 2A): Sterna and terga 2–6 simple. Posterior of tergum 7 with small median hump less prominent than that of Neoperla oculata with fewer sensilla basiconica. Tergum 8 without process, median with sensilla basiconica and long setae. Tergum 9 median with sparsely arranged long setae. Hemitergal lobe with simple dark edges and sparse quite long setae. Hemitergal lobe process curved sinuously and slightly raised in lateral view.

Aedeagus ( Fig. 2C): Aedeagal tube plump, larger second medioventral lobe heavily covered with spines, small but more distinct basolateral lobes covered with fine spines, distinctly smaller but densely covered midlateral lobes, and aedeagal sac bent less ventrally.

Egg ( Figs 4C–D): Color dark brown, shape spherical ovoid, hatching line visible. Length ca. 315 μm, width ca. 210 μm. Punctate chorion with more proportionate hexagons in the collar end. Micropyles small, nearly unnoticeable.

Differential Diagnosis. At first glance, the aedeagus resembles that of N. oculata because the defining characteristic in the key provided in Sivec (1984) is “two ventral outgrowths, a pair of subterminal lateroventral outgrowths, and a pair of dorsolateral outgrowths.” The illustration in Sivec (1984: 31) with caption “variation from Rizal’’ more closely resembles the aedeagus of the specimen at hand. However, the specimens examined in this study were found in Mindanao. This is also different from the “typical form” of N. oculata aedeagus. Hence, it is distinct from both forms of N. oculata . Morphologically, the obvious differences of N. philippinensis sp. nov. from N. oculata in the aedeagus are as follows: larger second medioventral lobe heavily covered with spines, small but more distinct basolateral lobes covered with fine spines, distinctly smaller but densely covered mediolateral lobes, and a less ventrad-bend to the aedeagal sac. The genetic divergence distances ( Table 2) also show that this is a different species from the N. oculata (6.49–7.58% interspecific genetic distance).

Nymph. Unknown.

Etymology. The specific epithet refers to the name of the country of origin, Philippines, where stonefly species diversity has been overlooked for the past decades.

Distribution. This species is known so far only from Mindanao, Philippines.