Mahasena ekeikei (Bethune-Baker), 2025

Beaver, Ethan P. & Zwick, Andreas, 2025, Two genera newly recorded from Australia: Mahasena Moore and Manatha Moore (Lepidoptera: Psychidae: Oiketicinae), each with a new species, Zootaxa 5711 (4), pp. 563-578 : 569-572

Mahasena ekeikei (Bethune-Baker) , comb. nov.

( Figs 2C–F ; 3B, F–G )

= Claniades ekeikei Bethune-Baker, 1908 : pg. 182; Dalla Torre & Strand (1929): pg. 186; Sobczyk (2011a): pg. 88; Sobczyk (2020): pg. 124, 126, 132–133, fig. 25.

= Mahasena corbetti Tams —[as misidentification]: Hӓttenschwiler et al. (2013): pg. 243–244, 246–249, 257 (key), Figs 3B , 4B , 5B, 6B, 7B, 8B, 9B; Sobczyk (2011b): pg. 251, Figs 7, 27–28.

= Lomera sp. — [as misidentification]: Kumar 2001: pg. 221, Fig. 11.4

Type data. Holotype. ♂ “ Ekeikei , B.C. New Guinea, 1,500 ft., March–April, 1903. A.E. Pratt. Coll. ”, “G. T.B- Baker Coll. Brit.Mus. 1927-360” “Type”. In NHMUK.

Type locality: Ekeikei , Papua New Guinea .

Other material examined. 20 ♂. 1 ♂ “ NEW GUINEA Torricelli Mountains, Mokai , 2500 ft, 8 Dec 1958 – 23 Jan 1959, W. W. Brandt”, “ MOKAI ”, “ Mahasena ekeikei , Genitalia prep. no. EPB-244, ANIC NULS752114 ”, “ ANIC Database No. 31-084647” . 7 ♂ with data identical to first two labels of the previous specimen. 1 ♂ “ NEW GUINEA, Finisterre Range, Gabumi , 2000 ft, 23 June–21 July 1958, W. W. Brandt.”, “Sibog” . 2 ♂ “ NEW GUINEA, Kiunga, Fly River , 2 Jul.–31 Oct. 1957, W. W. Brandt ”, “kg 6/8” . 1 ♂ “ NEW GUINEA, Maprik , East Sepik Province, at light, June 1975 ”, “F. Gerrits collection” . 2 ♂ “WOODLARK ISLAND, Kulumadau, 20 Jan–6 May, 1957, W. W. Brandt ”, “KA 1/3”. 3 ♂ ‘MISIMA ISLAND, Umana Camp , 500 ft, 6.11.– 7.12.1963, W. W. Brandt ”, “ MSMA ” . 1 ♂ “NORMANBY ISLAND, Wakaiuna, Sewa Bay , 23 Oct. 1956 – 11 Jan 1957, W. W. Brandt ”, “wk20/12” . 1 ♂ “ROSSEL ISLAND, Abaleti , 2.10– 2.11.1963, W.W. Brandt ”, “ RSSL ” . 1 ♂ with case “ Papua New Guinea, West New Britain, Bebere plantation, Division 2 oil palm, coll. 3.1.2009, em. 9.ii.2009, CF Dewhurst”, “ Mahasena corbetti Tams, 1928 , det. 2013 Hӓttenschwiler”, “ Mahasena ekeikei , Genitalia prep. no. EPB-243, ANIC NULS752789 ”, “ ANIC Database No. 31-084646”. All in ANIC .

Diagnosis. Mahasena ekeikei is similar to M. corbetti and M. inornata sp. nov., however can be differentiated on the basis of wing colour and scale characteristics and male genitalia, as given under the Diagnosis section for the previous species. In M. corbetti there is a clear distinction in the colour of the fore- and hindwing, in which the forewing is variously mid and reddish brown and the hindwing is fuscous black ( Tams 1928). See Fig. 5 of Leong & Lim (2012) where this quality is visible. This is not apparent in any specimen of M. ekeikei . Genitalia also differentiate M. ekeikei from M. corbetti . Proportionally, the saccus of M. ekeikei is wider and longer than in M. corbetti , the vinculum of M. ekeikei is also broader, and the tegumen shorter with the apex blunter than in M. corbetti .

Redescription. Male. ( Figs 2C–F ; 3B, F–G ). Eye index: 0.92. Forewing Length: 13–15 mm. Wingspan 27–29 mm.

Head. Antennae brown, bipectinate, 22–25 flagellomeres, apical flagellomere filiform, rami with single row of black scales dorsally, setae laterally and ventrally, rami 7x width of flagellomere at widest point. Frons and vertex brown piliform scales.

Thorax. Densely clothed with brown piliform scales on dorsal and ventral surfaces. Scales with weak purple iridescent quality when viewed at angle under bright white light. Legs brown, distal half of tarsi light brown. Foreleg with elongate epiphysis on proximal 1/3 rd of tibia; tarsi with apical spurs on tarsomeres. Forewing broad, triangular; costa nearly straight, convex toward pointed apex; termen slightly convex, sometimes with subtle concavity at CuA 2, inner margin concave sub-medially. Hindwing costa convex; apex rounded, termen subtly convex, inner margin convex after An 3. Wing venation typical; forewing with four Rs veins, three M veins with M 2 and M 3 stalked; Hindwing with M 2 and M 3 stalked, three An veins. Fore- and hindwing dorsal colour cinnamon brown. Hindwing with area between costa and R 2 khaki brown from basal area to apex, inner margin with dark brown piliform scales. Both fore- and hindwings dark cinnamon brown ventrally, dark brown fringe scales and lighter brown in area between inner margin up to and just beyond vein An+CuP, from basal area to middle. Wings with faint iridescent purple quality when viewed at lateral angle. Wing ground scales oval, pointed apex, medial ridge. Fringe scales broad, with four to five points, gaps between points very shallow on forewing but deep on hindwings.

Abdomen dorsally and ventrally brown, piliform scales attached to transparent membrane posterior and lateral to otherwise naked but highly sclerotised sternites and tergites.

Genitalia. ( Fig. 3B ). Saccus narrow, elongate, drawn to a point at apex, greater than ½ total length of genitalia complex, rest of vinculum flared laterally, with medial depression. Tegumen sclerotised laterally, concave, fused with vinculum, posteriorly broad, postero-lateral corners straight, blunt apex, setose on dorsal aspect. Valva elongate; apex bifurcate to two lobes, ventral lobe shorter than dorsal, recurved, with three to four short spines at apex; dorsal lobe broader, longer, rounded, setose dorsally; inner margin weakly convex, setose dorsally; basal costal lobe broad, sub-triangular, depressed medially. Phallus very long, greater than entire length of genitalia; sinuate, ductus ejaculatorius smooth, and vesica sub-triangular at phallus apex, densely covered with numerous long, highly sclerotised cornuti over entire length.

Female and immature stages are described in Hӓttenschwiler et al. (2013).

Biology. The larval biology of Mahasena ekeikei has been briefly described and illustrated by Hӓttenschwiler et al. (2013), under the name Mahasena corbetti . The larval bags ( Fig. 2F ) are usually 35–50 mm long in males, and 60–80 mm for females, and as for all known Mahasena , are irregularly adorned with a diverse range of foliage fragments, though occasionally produce bags almost devoid of material ( Hӓttenschwiler et al. 2013). Natural hostplants remain unrecorded, but both Hӓttenschwiler et al. (2013) and Kumar (2001) list the oil palm Elaeis guineensis as a host in plantation settings, where the species can have serious impacts. Hӓttenschwiler et al. (2013) remarked that the larvae have “a wide food plant spectrum” (pg. 247) suggesting a degree of polyphagy, but they do not specifically list any associated hostplants. The psychid bag illustrated in Kumar (2001: pg. 221, Fig. 11.4) labelled as a Lomera sp. bares a strong resemblance to the bags constructed by Mahasena ekeikei and is attributed to this species and not Lomera , which do not occur outside of Australia. Room (1980) refers to Plutorectis (a synonym of Lomera ), as a plantation pest from New Guinea, but this again likely refers to Mahasena ekeikei . The flight period is primarily April–June, though specimens from outside this period are known. Males appear to be nocturnal and are collected at light at night. Females produce between 1000–3000 eggs, with egg duration just over two weeks, larval duration 12–17 weeks, and pupal duration 3–4 weeks ( Hӓttenschwiler et al. 2013).

Habitat. The collection localities for this species principally correlate with lowland tropical rainforest in an elevational range from sea level to 760 meters. Mahasena ekeikei also occurs within agricultural areas such as oil palm plantations that are surrounded by natural forest or mixed use areas, especially in West New Britain, Papua New Guinea ( Kumar 2001, Hӓttenschwiler et al. 2013).

Distribution. Mahasena ekeikei is widespread across Papua New Guinea, from Kiunga (Western Province), the Torricelli Mountains ( Sandaun Province), Maprik ( East Sepik Province) Gabumi ( Madang Province), Woodlark Island, Misima Island, Normanby Island, and as far east as Rossel Island (all within the Milne Bay Province), Lorengau ( Manus Province) as well as from the Bismark Archipelago from Togulo and Bebere Plantations ( West New Britain Province). The type specimen is from Ekeikei, Papua New Guinea, an uncertain locality. The species may be widespread in West Papua, Indonesia, but is currently known only from Kota Nica and Merauke, coastal localities in the extreme north and south, respectively. Mahasena ekeikei is the only species of Mahasena currently known from New Guinea and the Bismark Archipelago. Kamarudin et al. (1994), and Hӓttenschwiler et al. (2013) refer to specimens from the Solomon Islands and from Samoa but these are unknown to us and so are treated simply as Mahasena sp. pending examination.

Remarks. Due to the synonymy of the genus Claniades with Mahasena , we transfer this species accordingly to Mahasena , and clearly diagnose it with respect to M. corbetti and M. inornata sp. nov., the only similar species. The holotype of M. corbetti is from Tapah, Peninsula Malaysia, and sequenced specimens from this region differ significantly by way of COI barcode ( Fig. 1 ). It is due to this, and the morphological differences outlined in the Diagnosis that we choose to retain M. ekeikei as a valid species.

This species is commonly called the Rough Bagworm in New Guinea ( Kumar 2001; Hӓttenschwiler et al. 2013).

Figures

FIGURE 1. Maximum likelihood phylogram of 17 Mahasena and 12 Manatha samples with outgroups Amatissa and Clania, based on mt COI barcode sequences. To the right are the six key taxa of interest in the present study, in descending order; Mahasena corbetti Tams, Mahasena inornata sp. nov., Mahasena ekeikei (Bethune-Baker) comb. nov., Manatha conglacia Hättenschwiler et al., Manatha prolixa sp. nov., and Manatha albipes Moore. The two new species are highlighted by pinkpurple gradient for Mahasena inornata sp. nov., and by light to dark blue gradient for Manatha prolixa sp. nov.

FIGURE 2. Mahasena species of Australia and New Guinea, dorsal and ventral; A–B, M. inornata sp. nov. holotype male from near Weipa, Queensland, Australia; C–F, M. ekeikei comb. nov.; C–D, male from Torricelli Mountains, Papua New Guinea; E, holotype, from Ekeikei, F, larval bag from Bebere Plantation, West New Britain, anterior aperture to the left. Scale bars all 10 mm.

FIGURE 3. Morphological details of Mahasena spp.: M. inornata sp. nov., A, male genitalia (paratype, voucher EPB-237); C, wings prepared and stained to visualise venation structure; D, forewing fringe scales; E, hindwing fringe scales; M. ekeikei comb. nov., B, male genitalia (voucher EPB-244); F, forewing fringe scales; G, hindwing fringe scales. Note the grey bar in E and G denote the position of the wing membrane, to aid in comparison of scale proportions in both figures. Scale bar in A and B = 500 µm, C = 2 mm, D–G = 200 µm. Abbreviations for genital structures: Bl = Basal costal lobe. Cr = cornuti. Ph = phallus. Su = saccus. Te = tegumen. Va = valva. Vi = vinculum. For wing venation: An = Analis. CuA = Cubitus anterior. CuP = Cubitus posterior. M = Media. R = Radius. Rs = Radial sector. Sc = Subcosta.

FIGURE 4. Morphological details of Manatha spp: A–B, M. prolixa sp. nov., holotype male from Kutini Payamu, Queensland, Australia; A, dorsal; B, ventral; C–G, male genitalia of M. prolixa sp. nov. (voucher EPB-239) and M. conglacia (voucher EPB- 246); C, close-up of valva of M. conglacia, D, valva of M. prolixa sp. nov.; E, close-up of phallus apex of that species showing cornuti; F, genitalia of M. prolixa sp. nov., G, genitalia of M. conglacia. Scale bar for A–B = 5 mm, C–E = 250 µm, F = 500 µm. Note difference in size as indicated by scale bars in F–G. Abbreviations for genital structures: Bl = basal costal lobe. Cr = cornuti. Ph = phallus. Su = saccus. Te = tegumen. Va = valva. Vi = vinculum.