Acalyptris brunipexus Stonis, Diškus & Remeikis, 2020

Stonis, Jonas R., Remeikis, Andrius, Diškus, Arūnas & Navickaitė, Asta, 2020, Documenting new and little known leaf-mining Nepticulidae from middle and southwestern areas of the Asian continent, Zootaxa 4881 (3), pp. 401-452 : 424-425

Acalyptris brunipexus Stonis, Diškus & Remeikis , sp. nov.

( Figs 18–21 , 82, 83 , 206–214 )

urn:lsid:zoobank.org:act:3A306391-5FFE-4732-9ED0-F85B6ABF44BC

Type material. Holotype: ♂, India, Uttarakhand, Dehradun Distr., Rishikesh , 30°07’41”N, 78°18’59”E, elevation ca. 510 m, 08.viii.2010, A. Diškus and A. Navickaitė, genitalia slide no. AD495 ( ZIN) . Paratypes: 4 ♂, 5 ♀, same label data as holotype, genitalia slide nos AD 482♂, AD 486♀, AD 497♂ ( ZIN) ; 1 ♂, same label data as holotype, 30°07’40”N, 78°19’03”E, elevation ca. 450 m, at light, 08.viii.2010, A. Remeikis and J. R . Stonis , genitalia slide no. RA278 ( ZIN) .

Diagnosis. This new species belongs to the Acalyptris platani species group. A. brunipexus sp. nov. is the most similar, and probably closely related, to the Himalayan A. melanospila ( Meyrick, 1934) , A. auratilis Puplesis & Diškus, 2003 , and A. nigripexus Puplesis & Diškus, 2003 .

Externally, males of A. brunipexus differ from similar species of the A. platani group in the presence of long, pale brown androconia ( Fig. 83 ) which cover the basal two-thirds of the hindwing and overlaps the fringe ( A. auratilis does not possess androconia, A. melanospila has a basal patch of white androconia, and A. nigripexus has distinctly black androconia).

Internally, in the male genitalia, the combination of unique-shaped ventral carinae ( Figs 210 , 211 ), presence of a cluster of spine-like cornuti in the phallus ( Figs 208, 210 , 213 ), the large, unique, hook-like cornutus ( Figs 208 , 213 ), the stout tube of the phallus ( Fig. 208 ), and the unique shape of the proximal lobes of vinculum ( Fig. 207 ) distinguish the new species from the most similar species, A. melanospila , A. auratilis , and A. nigripexus . Additionally, the little chitinized apex of the phallus ( Figs 208, 210 ) distinguishes A. brunipexus from A. auratilis (the latter possesses a strongly chitinized, rounded apical lobe), and the simply shaped inner lobe of the valva ( Fig. 207 ) distinguishes A. brunipexus from A. nigripexus (for an illustrated review of the similarHimalayan A. melanospila , A. auratilis , and A. nigripexus see Puplesis & Diškus 2003: figs 423–428, 477–495).

Male ( Fig. 83 ). Forewing length 1.5–1.6 mm; wingspan 3.2–3.5 mm (n = 2).

Head. Palpi cream, frontal tuft grey-brown; collar inconspicuous, cream, comprised of short piliform scales; scape brownish cream with some pale brown scales; antenna significantly shorter than one-third the length of forewing, with about 21 segments; flagellum pale brown basally, paler apically, sometimes with some purple iridescence.

Thorax. Tegula and thorax brownish cream, irregularly speckled with some brown scales. Forewing ochreous cream, with some purple iridescence, basally irrorated with pale grey-brown scales, apically densely speckled with black-brown scales; fringe cream, without a fringe line; underside of forewing pale ochre-brown, with some purple iridescence, without spots or androconia on upper side and underside. Hindwing covered with slender, long, pale brown androconia with purple iridescence, except for the apical third of the wing which is cream; the long, brown androconia also overlap the fringe. Legs glossy yellowish cream; hindlegs covered with brown scales on upper side.

Abdomen. Dark grey-brown with some purple iridescence on upper side, predominantly cream on underside. Otherwise, abdomen is unknown. Genitalia ( Figs 206–213 ) with capsule about 190–200 µm long, 125–130 µm wide. Pseuduncus ( Figs 206 , 212 ) triangular-shaped, truncated or rounded distally. Valva ( Figs 207 , 211 ) 125–130 µm long, with an inner lobe. Vinculum with moderately long, triangular-shaped lateral lobes and two unique proxi-mal lobes ( Fig. 207 ). Phallus with a stout tube (not constricted medially) ( Figs 208–210 , 213 ), about 205 µm long, with a unique-shaped ventral carinae ( Figs 210 , 211 ), some tiny cornuti, an apical cluster of 5–7 spine-like cornuti ( Figs 208, 210 , 213 ), a large sinuous cornutus ( Figs 208, 209 ), and large, unique, hook-like cornutus ( Figs 208, 209 , 213 ).

Female ( Fig. 82 ). Forewing length 1.5–1.7 mm; wingspan 3.2–3.7 mm (n = 4). Similar to male, but lighter in color. Frontal tuft pale ochreous orange. Scape golden cream, glossy. Antenna very short, curved, with about 16 segments; flagellum dark brown basally, pale yellowish brown in apically.

Forewing golden cream, sparsely speckled with dark-brown scales in the basal two-thirds and densely covered with black-brown scales in the apical third, sometimes forming a false fascia. Fringe glossy cream. Forewing underside glossy ochreous to glossy pale brown, without spots. Hindwing golden cream, glossy to pale brown-grey depending from angle of view. Legs glossy yellowish cream, with little or no brown scales on upper side.

Abdomen. Dark grey-brown with some purple iridescence on upper side, golden cream, glossy on underside. Genitalia ( Fig. 214 ) about 525 µm long. Abdominal apex truncated, with short setae; anterior and posterior apophy-ses equal in length. Vestibulum with a unique, weakly-developed and weakly-chitinized vaginal sclerite. Corpus bursae with two large signa; one signum is slightly shorter. Ductus spermathaecae with about 2 coils and a unique, round vesicle ( Fig. 214 ).

Bionomics ( Figs 18–21 ). Host plant is unknown (unidentified). Larvae mine in leaves in August and, judging from observed old (empty) leaf mines, in July. Larva pale yellowish green, with brownish green intestine and pale brown head ( Fig. 18 ). The leaf mine is linear, as a slender gallery, contorted in the beginning, further on sinuous, with a thin central line of black frass ( Figs 19–21 ). Adults occur in August–September.

Distribution. Known from a single locality in the western Himalaya (Uttarakhand: Rishikesh), at the elevation of about 500–700 m ( Fig. 1 : wHi).

Etymology. The species is named after the similar A. nigripexus (possessing black androconia), with a change of nigri - to bruni- (brown), in reference to the pale brown androconia of the hindwing of the new species.

Figures

FIGURES 16–28. Leaf mines of new species of Nepticulidae. 16, 17, Stigmella longa Remeikis & Stonis, sp. nov.; 18–21, Acalyptris brunipexus Stonis, Diškus & Remeikis, sp. nov.; 22–25, A. nasutus Diškus & Navickaitė, sp. nov.; 26–28, Ectoedemia orbiculata Diškus, Remeikis & Stonis, sp. nov.

FIGURES 81–86. Adults of Acalyptris spp. 81, A. noctilucus Rocienė & Stonis, sp. nov., male holotype; 82, A. brunipexus Stonis, Diškus & Remeikis, sp. nov., female paratype; 83, same, male holotype; 84, A. auratilis Puplesis & Diškus, specimen AG127; 85, A. nasutus Diškus & Navickaitė, sp. nov., female holotype; 86, same, forewing venation, slide AD479b (ZIN).

FIGURES 206–210. Male genitalia of Acalyptris brunipexus Stonis, Diškus & Remeikis, sp. nov. 206, paratype, genitalia slide no. RA278, gnathos, uncus and pseuduncus; 207, paratype, genitalia slide no. AD497, capsule with phallus removed; 208, same, phallus; 209, holotype, genitalia slide no. AD495, large sinuous cornutus; 210, paratype, genitalia slide no. AD497, carinae (ZIN)

FIGURES 211–214. Genitalia of Acalyptris brunipexus Stonis, Diškus & Remeikis, sp. nov. 211, holotype, genitalia slide no. AD495, capsule with phallus inside; 212, same, gnathos, uncus and pseuduncus; 213, paratype, genitalia slide no. AD497, phallus; 214, paratype, genitalia slide AD486, female genitalia (ZIN)

FIGURES 1–6. A geographical map (courtesy of T. Patterson, USA) and new host plants of Nepticulidae. 1, localities in this study; 2, 3, Ototropis elegans (DC.) H. Ohashi & K. Ohashi, Fabaceae, a host plant of Stigmella longa sp. nov.; 4, Viburnum cotinifolium D. Don., Adoxaceae, a host plant of Acalyptris nasutus sp. nov; 5, Ototropis sp., Fabaceae, a host plant of Stigmella pyramidata sp. nov.; 6, Spiraea canescens D. Don., Rosaceae, a host plant of Ectoedemia orbiculata sp. nov.