Dvidulopsis Stonis & Diskus 2025, gen. nov.
Creators: name: Stonis, Jonas R.
name: Diškus, Arūnas
name: Remeikis, Andrius
name: Orlovskytė, Svetlana
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Nepticulidae
Dvidulopsis

description: Dvidulopsis Stonis & Diškus, gen. nov.
urn:lsid:zoobank.org:act: 73AC80A1-AA68-4104-9A72-00CA9505F628
(Figs 1–31)
Type species: Dvidulopsis amazonensis (Stonis & Diškus, 2018) comb. nov.
(deposited at NHMUK).
Diagnosis. Adult moths are characterized by wide forewings with a distinct oblique, dark, postmedian or subapical pseudofascia. The genus is easily distinguishable, including from the most similar Fomoria Beirne and Acalyptris Meyrick, by the following unique combination of male genitalia characteristics: the uncus and gnathos are fully divided (paired) or at least partially divided; the valva possesses an inner (median) process or lobe; the phallus lacks cornuti but has three distinctive, elongated carinae; and the phallus tube is constricted basally. In all cases, the clade of Dvidulopsis gen. nov. consistently appeared as a distinct, separate phylogenetic entity (see the subchapter “Molecular considerations”).
Description. External characters (Figs 1–6). The forewing is relatively wide, in contrast to most Nepticulidae species, which typically have more slender forewings. The scaling of the forewing is often yellowish cream and always features a distinct oblique, dark, postmedian or subapical fascia-like marking. While some Acalyptris species also exhibit an oblique postmedian marking, it is generally less distinctive and persistent compared to that in Dvidulopsis gen. nov. The forewing venation (illustrated in Puplesis & Diškus, 2018: Figs. 10–12) resembles that of Acalyptris and is similar to that of the Central American A. bovicorneus Puplesis & Robinson (see illustrated in Puplesis & Robinson, 2000: Fig. 65). A closed cell is formed by an indistinct, and possibly rudimentary, vein Rs+M.
Characters of the male genitalia (Figs 7–20). The phallus is characterized by three large, horn-like carinae apically—a unique and likely apomorphic feature not found in the resembling Acalyptris. Lobe-like or lateral carinae are absent. The phallus tube is often constricted at the basal part, particularly in the informal and undescribed D. onorei species complex, a feature not characteristic of Acalyptris and possibly an apomorphy of Dvidulopsis gen. nov., or at least of the D. onorei species complex. The uncus is clearly paired and, in the D. onorei species complex, strongly developed, which seems to be an apomorphic character. In Neotropical Acalyptris, the uncus is unpaired, typically forming an inverted V or Y shape. The gnathos is paired and often partially reduced, with exceptions in two species: D. latipennata (Puplesis & Robinson), which has an unpaired gnathos with one caudal process and distinctive lateral arms, and D. diviantis sp. nov., which has a slightly different, still bilobed gnathos. In contrast, the majority of Neotropical Acalyptris species have a stout gnathos with one caudal process. The valva features a large inner (median) process, except in D. ecuadoriana (Puplesis & Diškus). Few Neotropical Acalyptris species have a valva with an inner process, and when present, it is not morphologically homologous to that of Dvidulopsis gen. nov. The sublateral processes of the valva are always long or very long, whereas only some Neotropical Acalyptris species have rather long sublateral processes. The transtilla always has a transverse bar, unlike most Acalyptris, where the absence (rather than the presence) of a transverse bar is more typical. The juxta usually present but small. The vinculum is large or very large, except in D. ecuadoriana, which has a moderately large vinculum. The posterior margin of the vinculum usually has either two short, rounded lobes or one short, rounded lobe.
The lateral apodemes, unique structures characteristic of the male genital capsule of Acalyptris, are usually absent in Dvidulopsis gen. nov.
Female genitalia. Known from an illustrated D. latipennata specimen by Puplesis & Robinson (2000); however, this specimen was excluded from the type series by later authors, and therefore, because of some uncertainty, the female genitalia are not discussed here.
Biology. The host plant is known only for the type species, D. amazonensis (Stonis & Diškus, 2018). Larvae of the latter species mine leaves of Psychotria L. (Rubiaceae). The leaf mine (illustrated in Stonis & Diškus, 2018) is a sinuous to very contorted gallery, with dark green to black-green or brown-green frass variously deposited at certain stages of development. Exit slits of the type species are on the upper side of the leaf; the cocoon is round, 2 mm long, 1.5 mm wide, yellowish beige, and not glossy (matte) (Stonis & Diškus, 2018).
Distribution: The species of this genus are known exclusively from lowland tropical forests of the Neotropics, from southwestern Mexico, Belize and Honduras (Fig. 26) in the north to equatorial Ecuador in the south (Figs 27, 28).
Taxonomic composition. The following species are included in the genus Dvidulopsis gen. nov.: D. latipennata (Puplesis & Robinson, 2000), comb. nov.: Belize (Chiquibul forest) and Honduras, 2 ♂, 7.5 km SE of La Ceiba, right bank of Rio Cangrejal, 100 m, 15°43ʹ34″N, 86°44ʹ26″W, 14.iv.2023, leg. J.R. Stonis, genitalia slide nos RA1224 ♂, RA1223 ♂ (MfN) (new distribution); D. dividua (Puplesis & Robinson, 2000), comb. nov.: Belize (Chiquibul forest); D. paradividua (Šimkevičiūtė & Stonis, 2009), comb. nov.: Mexico (Pacific coast) (Šimkevičiūtė et al. 2009); D. ecuadoriana (Puplesis & Diškus, 2002), comb. nov.: Ecuador (Región amazónica); D. onorei (Puplesis & Diškus, 2002), comb. nov.: Ecuador (Región amazónica); D. insolentis (Puplesis & Diškus, 2002), comb. nov.: Ecuador (Región amazónica) (Puplesis et al. 2002a); D. amazonensis (Stonis & Diškus, 2018), comb. nov.: Ecuador (Región amazónica); D. diviantis Stonis & Remeikis, sp. nov.: Honduras (Atlantída Department) (described below).
Etymology. The new genus name Dvidulopsis is a noun of neutral gender. It is a unique combination of Lithuanian and Greek elements, crafted to emphasize the genus's distinctive morphological characteristics. The prefixes “Dvi-” (feminine) and “du” (masculine) means “two” in Lithuanian. This deliberate combination of “dvi” and “du” underscores the dual nature of the genus, specifically referring to the two structures of the male genitalia, the uncus and gnathos, each fully or partially divided into two lobes (or processes). The suffix “-opsis” is from the Greek word “opsis”, meaning “appearance” or “resemblance”.
Molecular considerations of Dvidulopsis gen. nov.
For our molecular analysis, we successfully obtained three new mtDNA CO1-5' sequences for Dvidulopsis diviantis sp. nov. and D. latipennata (Puplesis & Robinson).The latter was originally described from the tropical humid forests of Belize as Fomoria latipennata (Puplesis & Robinson, 2000). Two years later, it was transferred to Acalyptris Meyrick and became the eponymous species of the former Acalyptris latipennata group (Puplesis et al. 2002b). In the current study, this group was excluded from Acalyptris and due to its striking morphology, the latipennata group was elevated to a taxonomic rank, resulting in the creation of the new genus Dvidulopsis gen. nov. This is why, to justify the phylogenetic status of the new genus and its species, our current molecular analysis included several species from the morphologically similar genera Acalyptris Meyrick and Fomoria Beirne.
In all of our reconstructed phylogenetic trees, the two sequenced species of Dvidulopsis gen. nov. clearly differed from Acalyptris species and consistently clustered together with a high degree of reliability (ML probability value of 87%) (Fig. 29). When we included the morphologically resembling genus Fomoria Beirne in the analysis, Dvidulopsis gen. nov. still diverged from both Acalyptris and Fomoria, appearing as a sister clade to Acalyptris + Fomoria (ML probability value of 87%). Additionally, we included Ectoedemia, which is closely related to Fomoria and Acalyptris (see Fig. 4 in Doorenweerd et al. 2016). It is interesting that some Ectoedemia species clustered within the Acalyptris clade in our analysis. However, after removing most of the Acalyptris species, Ectoedemia formed a distinct clade with an ML probability value of 85% (Fig. 30). In this tree, Dvidulopsis gen. nov. also showed clear distinction, forming a well-supported dichotomy with Fomoria + Acalyptris + Ectoedemia (ML probability value of 94%).
In all cases, the clade of Dvidulopsis gen. nov. consistently appeared as a distinct, separate phylogenetic entity. These results align well with the unique morphology of the genus Dvidulopsis gen. nov. and its species, supporting the erection of this new genus.
description: Published as part of Stonis, Jonas R., Diškus, Arūnas, Remeikis, Andrius & Orlovskytė, Svetlana, 2025, Dvidulopsis gen. nov., a rare Neotropical genus of pygmy moths (Nepticulidae) endemic to lowland humid forests, a biome of conservation priority, pp. 583-599 in Zootaxa 5609 (4) on pages 586-592, DOI: 10.11646/zootaxa.5609.4.8, http://zenodo.org/record/15215526