Gnathitischeria Diškus, 2023

Stonis, Jonas R., Diškus, Arūnas, Remeikis, Andrius, Orlovskytė, Svetlana, Solis, Alma, Paulavičiūtė, Brigita, Xu, Jiasheng & Dai, Xiaohua, 2023, Genera of Tischeriidae (Lepidoptera): a review of the global fauna, with descriptions of new taxa, Zootaxa 5333 (1), pp. 1-131 : 107

11. Genus Gnathitischeria Diškus gen. nov.

urn:lsid:zoobank.org:act:67617B46-AA1E-4BF0-9CB6-2316094988EC

( Figs 482–561 )

Type species: Gnathitischeria atitlani Diškus & Stonis , sp. nov. (described below).

Diagnosis. Externally, Gnatitischeria species are characterized by a pale (grey cream or ochreous cream) apical spot on the forewing ( Figs 485, 489 ); females of the type species G. atitlani sp. nov. possess a distally cream antenna ( Figs 487, 488 ). In the male genitalia, species of Gnathitischeria are easily recognizable by presence of a unique pseudognathos, a modified uncus, a frame-like thickening of tegumen, and a divided valva with a dorsal lobe (process). In the female genitalia, the genus is characterized by small, but spinose, lateral lobes of the ovipositor and a weakly developed caudal plate of the prela. Leaf mines of Gnathitischeria are irregular blotch-like or elongated with a triangular initial part, on Asteraceae and Malvaceae host plants; a nidus is indistinctive. See Tabs 2 , 3 for occurrence of these diagnostic characters in other genera of Tischeriidae .

Notes. In our molecular trees, Gnathitischeria appeared as a separate clade at the generic rank. It clusters either with ( Astrotischeria + Paratischeria ) ( Fig. 62 ), or only with Astrotischeria ( Figs 63, 64 ).

Adult. Head: frontal tuft overlapping the frons, comprised of long relatively wide lamellar scales; pecten relatively short and slender; collar indistinctly paired or coalescent, comprised of relatively slender lamellar scales. Female of G. atitlani with distinctly cream antenna distally. Male forewing with elongated but irregular spots; female forewing with significantly brighter, ochre-yellow elongated spots; forewing apex with a fringe line and pale spot (grey cream in male and female of G. arcana , and ochre cream in female of G. atitlani ). Hindwing slender, androconia absent.

Male genitalia. Uncus modified, comprised of two wide lobes with variously developed lateral thickenings. Socii membranous, unusually large, almost unpaired and indistinctly spinose. Tegumen greatly modified: moderately short however, unlike other Tischeriidae (excluding Manitischeria ), tegumen with a frame-like thickening and well-developed, large pseudognathos; diaphragm without spines. Valva divided, with ventral and dorsal lobes; basal process of the valva long. Transtilla and juxta absent. Anellus membranous, thickened only caudally or absent. Vinculum long, ventral plate widely rounded distally. Phallus slender, rod-like, apically with wide lateral lobes, without spines.

Female genitalia. Ovipositor lobes large to medium large; the gap between ovipositor lobes large to very large; second pair of ovipositor lobes usually two times smaller in comparison to main ovipositor lobes; lateral lobes small and with tiny spines. Anterior apophyses either slightly longer or shorter than posterior apophyses. Prela with three pairs of long or very long rod-like projections; transverse prela unusually wide but indistictive proximally; membrane between inner prela is not thickened. Caudal sclerite weakly developed, indistinctive. Antrum absent. Accessory sac absent or small; ductus spermathecae slender, with 4–5 coils; vesicle relatively large, irregularly shaped. Corpus bursae long, gradually narrowing caudally; pectinations only proximally or absent.

Bionomics. The genus is trophically associated with Asteraceae and Malvaceae host plants. Leaf mines of Gnathitischeria are either irregular blotch-like or irregular elongated with a triangular initial part, without frass; a nidus is indistinctive, a disturbed larva hides under a large vein of the leaf.

Species diversity and geographical distribution. Currently, the genus is comprised of only two species, both known from Central America ( Guatemala).

Etymology. The genus name is combined from the ancient Greek gnathos (in this case, a structure of the male genitalia) and Tischeria (a name of the type genus of Tischeriidae ) referring to the presence of the unique pseudognathos in the male genitalia.

Figures

FIGURE 62. The Maximum Likelihood tree of 11 randomly selected sequences of species representing 11 genera of Tischeriidae (Table 1 + downloaded Paratischeria ferruginea HM244395, Neotischeria neotropicana HM244391, Dishkeya bifurcata LNAUT3265-15, Coptotrichoides serjaniphaga OK017167) based on the 608 bp long mtDNA CO1-5’ sequences). The Kimura 2-parameter model (1.000 replicates) was used to calculate divergence. The best supported and resolved dichotomies are highlighted. The morphological differences of genitalia are shown to the right of the tree

FIGURES 482–493. Adults of Gnathitischeria spp., Guatemala, Central America. 482–485, G. arcana Diškus & Stonis, sp. nov. (MfN); 486–493, G. atitlani Diškus & Stonis, sp. nov. (MfN)

FIGURES 494–501. Male genitalia of Gnathitischeria atitlani Diškus & Stonis, sp. nov., paratype, genitalia slide AD1097 (MfN). 494, 495, ventral and lateral view of capsule with phallus inside; 496–501, uncus, tegumen and pseudognathos at different angle of view

FIGURES 502–508. Details of male genitalia capsule of Gnathitischeria atitlani Diškus & Stonis, sp. nov., paratype, genitalia slide AD1113 (MfN). 502–506, uncus, tegumen and pseudognathos; 507, 508, vinculum and valvae with dorsal processes

FIGURES 509–512. Male genitalia of Gnathitischeria atitlani Diškus & Stonis, sp. nov., holotype, genitalia slide AD1071 (MfN)

FIGURES 513–518. Details of male genitalia capsule of Gnathitischeria atitlani Diškus & Stonis, sp. nov. 513, 514, 516–518, paratype, genitalia slide AD845; 515, paratype, genitalia slide no. AD1071 (MfN)

FIGURES 519–523. Female genitalia of Gnathitischeria atitlani Diškus & Stonis, sp. nov. 519, 520, paratype, genitalia slide no. AD846 (MfN); 521–523, another paratype, genitalia slide no. AD1039 (MfN)

FIGURES 524–534. Bionomics of Gnathitischeria atitlani Diškus & Stonis, sp. nov., Guatemala: Sololá Department, San Marcos La Laguna. 524, 525, host plant, Hibiscus sp., Malvaceae; 526–532, leaf mines; 533, feeding larva; 534, shadow of pupa visible under epidermis

FIGURES 535–542. Male genitalia of Gnathitischeria arcana Diškus & Stonis, sp. nov., paratype, genitalia slide AD847 (MfN). 535, membranous socii; 536, uncus; 537, 538, pseudognathos; 539, anellus; 540, general view of capsule with phallus removed; 541, phallus; 542, dorsal lobes (processes) of valva

FIGURES 543–549. Male genitalia of Gnathitischeria arcana Diškus & Stonis, sp. nov., holotype, genitalia slide AD1099 (MfN). 543, ventral lobes of valva; 544, details of lateral lobe of uncus; 545, socii; 546, phallus and pseudognathos; 547, caudal part of anellus; 548, general view of capsule with phallus inside; 549, basal part of pseudognathos

FIGURES 550–554. Female genitalia of Gnathitischeria arcana Diškus & Stonis, sp. nov., paratype, genitalia slide no. AD936 (MfN). 550, general view; 551, coils of ductus spermathecae; 552–554, ovipositor and apophyses

FIGURES 555–561. Bionomics of Gnathitischeria arcana Diškus & Stonis, sp. nov., Guatemala: Petén Department. 555, host plant, Acmella repens (Walter) Pers. (Asteraceae); 556–561, leaf mines

FIGURES 63, 64. The Maximum Likelihood trees of Tischeriidae based on the 608 bp long mtDNA CO1-5’ sequences. The Kimura 2-parameter model (1.000 replicates) was used to calculate divergence. The best supported and resolved dichotomies are highlighted. 63, using the same (as in the Fig. 62) 11 randomly selected sequences of species representing 11 genera of Tischeriidae; the families of host plants are shown to the right of the tree; 64, same, but omitting Rytietia uncinata sp. nov.; the distribution of species is shown to the right of the tree