Morabia pluto László & Hausmann 2022, comb. n.
Creators: name: László, Gyula M.
name: Hausmann, Axel
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Geometridae
Morabia
Morabia pluto

description: Morabia pluto (Viette, 1971), comb. n.
(Figs 18–19, 34, 42)
Ectropis pluto Viette (1971): 179. Holotype, male, Madagascar, Analamazaotra Forest, coll. MNHN.
Material examined. Madagascar. 1 male, Ankasoka, 1130m, Route Lakato, 30.xi.1956, leg. P. Griv., gen. slide No.: ZSM G 21272 (prepared by László); 1 female, Perinet, Analamazoatra forest, 910m, 18.i.1955, leg. P. Viette, gen. slide No.: ZSM G 21273 (prepared by László) (ZSM); 1 male, Env. D’Ambohimahasoa, canton de Tsarafidy, foret de Sahafohy, 1320m, vii.1969, leg. P. Soga; 1 male, Ankarampotsy, nr. Fianarantsoa, col de Tantamaly, Dec. 1933, leg. R. Catala, gen. slide No.: NHMUK 10317353 (prepared by László); 1 female, Station Perinet, 149 km east of Tananarivo, 20.x.-10.xi.1930, leg. Mme N. d’Olsoufieff, gen. slide No.: NHMUK 10317354 (prepared by László) (NHMUK).
Diagnosis. Based on the genital morphology, Morabia pluto represents a distinct lineage well-separated from the distinctaria-hero-herbuloti clade, showing closer kinship with the continental M. nigripunctata -lineage. The Madagascan taxon however, is clearly distinguished from its continental congener by the shorter and broader uncus, markedly shorter, more robust costal arms of the valva, the ventro-medially less deeply depressed valva with a less setose distal section and the shorter, but thicker cornutus of the vesica. Compared to the congeners from Madagascar and the Mascarene Archipelago, M. pluto is considerably larger, with more sinuous transverse lines than in M. hero and distinctaria, and although it is most similar to M. herbuloti, it displays noticeably thicker and more diffuse markings. The species is best distinguished by the wing pattern of the underside: M. pluto has the typical subapical blotches without a broad dark marginal area which is characteristic of the other taxa. In the male genitalia, the differences between M. pluto and the distinctaria-hero-herbuloti complex are expressed by the former species’ very short and broad, apically rounded uncus (which is elongate and much narrower in its congeners), the markedly narrower costal arms of the valva, the much larger, considerably less sclerotized and less setose valva and the lack of a saccular process. Additionally, the vesica of M. pluto bears a long and robust cornutus, whereas it is very short and thin, needle-like in the other taxa. In the female genitalia, M. pluto has a somewhat shorter, proximally broader 8 th tergite with a medially depressed distal margin (which is evenly convex in its congeners), a longer sclerotized section of the ductus bursae with longitudinal striation (it is smooth and more heavily sclerotized in the related species) and a markedly larger, more elongate signum bursae compared to those of the distinctaria-hero-herbuloti complex.
Re-description. Adult (Figs 18–19). Forewing length 17.5–20.0 mm. Antenna ciliate-fasciculate in male, filiform in female. Sexual dimorphism limited, female somewhat darker than male. Head relatively small, palp short, porrect, apically pointed, covered in brownish-grey scales. Compound eye relatively large, frons broad, quadrangular, brownish-grey with two dark brown hair tufts laterally, vertex pale grey. Collar, tegula and thorax brownish-grey, first abdominal segment black basally, off white distally, further segments brownish-grey, creamy-yellow ventrally. Upperside of wings. Ground colour brownish-grey, markings dark grey. Forewing. Basal and subbasal lines deleted; antemedial line narrow, ventral two-thirds slightly undulate, dorsal third curved towards costa, evenly arcuate, costal end with quadrangular patch. Discal spot blurred, small, short dash-like, oblique. Medial line diffuse, narrow, strongly zigzagged, costal end with quadrangular patch. Postmedial line narrow, but sharply defined, ventral quarter sinuous, medial half almost straight, costal quarter right angled towards costa, straight. Subterminal line diffuse, shadow-like, slightly arched, zigzagged. Terminal line sharply defined, relatively thick, gently sinuous between veins; cilia long, inner half creamy, outer half pale brownish, sparsely chequered with dark brown. Hindwing. Basal and antemedial line short, thick, straight. Discal spot small, blurred, round. Medial line thick, slightly undulate, postmedial line rather thick, gently zigzagged. Subterminal line diffuse, poorly visible or deleted, terminal line relatively thick, sinuous; cilia as on forewing. Underside of wings. Ground colour pale brown; discal spot sharply defined, small, black, elongate dash-like, forewing discal spot three times larger than that of hindwing. Transverse lines undetectable. Subapical area of fore- and hindwing with a large, rounded-quadrangular black blotch, forewing blotch two times larger than that of hindwing; terminal area of fore- and hindwing without dark band; cilia as on upperside.
Male genitalia (Fig. 34). Uncus conspicuously short, rounded trapezoidal, very broad at base, apically with two very short, rounded latero-distal protrusions covered in short, but stout setae. Gnathos very short and narrow, ribbon-like, V-shaped without dilated medial plate. Tegumen very short and broad, arms fused at their distal end only. Juxta very weakly sclerotized, rounded shield-like; vinculum very short and broad, saccus short and broad, rounded triangular. Valva very broad at base, weakly sclerotized, basal section finely scobinate, bearing a short but stout, medially angled, distally tapered, apically pointed, somewhat beak-like dorsal process (costal arm) with long and sparse setae in basal half and with a narrow line of dense, short setae in distal half. Medial section of valva slightly constricted, ventral margin with a short, very shallow medial depression; apical half sparsely setose with short, fine setae, gradually tapered distally, costal margin almost straight, valva apex rounded. Valva with a short, rounded lobe ventro-medially, bearing long, straight setae directing caudad. Sacculus relatively long and broad, moderately sclerotized, without processi. Aedeagus moderately long and narrow, anterior third gently arched ventrad, coecum short, broadly rounded, medial and posterior section straight, apex with a short, weakly sclerotized, rounded triangular process. Vesica armed with a single, long (half as long as aedeagus), slightly sinuous, robust, apically pointed cornutus.
Female genitalia (Fig. 42). Ovipositor moderately long, papilla analis elongate, apically rounded, sparsely setose, apophyses long and thin, posterior one ca. twice as long as anterior one. Eighth tergite broad-based trapezoidal, distal margin with a shallow medial depression, proximal margin almost straight. Eighth sternite rugose crosswise. Ostium bursae broad, ovoidal with moderately sclerotized margin, antrum short, heavily sclerotized, funnel-like. Ductus bursae moderately long, relatively thick, gradually dilated anteriorly, distal three-quarters moderately sclerotized, longitudinally striate, proximal quarter membranous. Cervix bursae very small, membranous, erected at distal end of ductus bursae. Corpus bursae ovoid, signum bursae relatively large, somewhat spearhead-shaped, with narrow, strongly sclerotized crest anteriorly and laterally encompassing a smooth, less sclerotized internal plate with deeply notched distal margin.
Genetic information. The authors could not trace specimens suitable for DNA sequencing.
Distribution (Fig. 43). Morabia pluto is endemic to Madagascar.
Remark. The female genitalia of M. pluto is described and illustrated here for the first time.
description: Published as part of László, Gyula M. & Hausmann, Axel, 2022, Taxonomic review of the genus Morabia Hausmann & Tujuba, 2020 with descriptions of two new species and introducing five new generic combinations (Lepidoptera, Geometridae, Ennominae), pp. 215-237 in Zootaxa 5134 (2) on pages 233-234, DOI: 10.11646/zootaxa.5134.2.3, http://zenodo.org/record/6534856