Monochroa monellii Corley & Rosete, 2025

Corley, Martin, Rosete, Jorge & Ferreira, Sónia, 2025, Monochroa monellii (Lepidoptera, Gelechiidae), a new species from Portugal, Nota Lepidopterologica 48, pp. 289-298 : 289-298

Monochroa monellii Corley & Rosete sp. nov.

Figs 1 , 2 , 6 , 10

Type material.

Holotype male. • Lagoa de S. José , Mata de Urso, Carriço, Pombal, Leiria, BL, 40°00'19.52"N, 8°52'03.19"W. Ex pupa on Lysimachia monelli , 18. vi. 2025, J. Rosete leg. | [Small white label] J. Rosete prep. gen. n o. 860 m. | [Red label] Monochroa monellii Corley & Rosete, 2025 sp. nov. HOLOTYPE. To be deposited in IZPC with code MHNCUP-ART-43666 .

Paratypes. All with same locality and collector. • Portugal, Lagoa de S. José , Mata de Urso, Carriço, Pombal, Leiria, 40°00'19.52"N, 8°52'03.19"W, 1 ♀, 13. viii. 2020, leg. J. Rosete, gen. prep. JR 56 f, in RCJR, to be deposited in IZPC with code MHNCUP-ART-43667 ; • 1 ♂, 3. ix. 2020, Rosete gen. prep. JR 50 m, DNA barcode INV 17383, in RCJR, to be deposited in IZPC with code MHNCUP-ART-43668 ; 1 ♂, 13. vii. 2024, Bioscan DNA Voucher, Sample ID: BGE_00575_D 12, Rosete gen. prep. JR 804 m , in RCJR ; • 1 ♂, 2 ♀, 29. vii. 2020, M. Dale gen. preps MD 02981 m, MD 02977 f (in RCMC), MD 02979 f (in RCJR) ; • 1 ♀, 13. viii. 2020, M. Dale gen. prep. MD 02978 f, in RCMC ; • 1 ♂, 3. ix. 2020, M. Dale gen. prep. MD 02961 m, in RCMC ; • 1 ♀, 3. ix. 2020, M. Dale gen. prep. MD 02980 f, in RCJR ; • 2 ♂, 1 ♀, 13. vii. 2024, in RCMC .

Description.

Wingspan 8‒10 mm. Head light grey; labial palps with segment 2 slightly thickened with scales, 1.1 times as long as segment 3, dark fuscous on outer side, whitish on inner side, segment 3 slender, whitish with a few darker scales on outer side, sometimes with a blackish partial ring at base; antenna fuscous, dark brown at distal end of each segment. Thorax grey. Forewing fuscous, small blackish spot or short dash in fold at one-quarter and spot at end of cell; fringes dark grey with scattered dark dots, sometimes with a distinct dark grey fringe line; hindwing three-quarters width of forewing, grey, fringes grey. Abdomen light fuscous.

Variation. Forewing scales may be uniformly dark brown, or paler towards base to a varying extent, resulting in variation in ground colour. In the darker specimens the blackish spots are obscure.

Male genitalia. Tegumen slightly more than half as long as valva, expanding distally, uncus a weak bulge, gnathos absent; valva with costal margin concave in middle, tapering from four-fifths to obtuse or truncate apex with one or two small teeth before apex, ventral margin with long gradual curve to digitate sacculus which extends very shortly beyond harpe which forms a very large oval flap; phallus with basal part longer than parallel-sided distal part, swollen in middle and with a large oval, thin-walled ‘ window’, cornuti very numerous, largest only slightly longer than those in the middle of the group.

Female genitalia. Posterior and anterior apophyses about equal in length; ostium opening at distal margin of segment VIII, antrum gradually tapering, ductus bursae twice as long as ovate corpus bursae with ductus seminalis arising at middle and colliculum at one-third ductus length from corpus bursae; signum a broad plate constricted in middle by a pair of chess pawn-shaped structures on the longitudinal axis.

Diagnosis.

Externally M. monellii sp. nov. is extremely similar to M. conspersella (Figs 3 , 7 ), M. servella (Figs 4 , 8 ) and M. tetragonella (Figs 5 , 9 ). The last species, according to Gregersen and Karsholt (2022) has much of the forewing with whitish scales thus looking paler. The specimens they illustrate are from localities around the Baltic Sea, but those from England (Fig. 5 ) are uniformly dark brown. All four species vary in the extent of pale coloration at the base of the scales which affects the overall coloration of the forewing. Reliable identification by morphology therefore depends on genitalia characters. In the male genitalia, M. monellii has the costal margin of the valva slightly concave in the middle, whereas the margin is straight or slightly convex in the other species. The phallus has a cluster of numerous cornuti, with little difference in size in M. monellii while in M. servella and M. conspersella the size of the cornuti increases considerably from one end of the cluster to the other, the longest cornuti being about 3 times as long as those in the middle of the cluster; in M. tetragonella the increase in size is less marked. Other differences are in the shape of the costal margin and apex of the valva and the length and shape of the sacculus. These features can be seen in Figs 6–9 . In the female genitalia there are differences between species in the shape of the signum, also clearly visible in Figs 10 – 13 .

DNA Barcode.

Specimen INV 17383 is currently the single representative of the BIN BOLD: AGQ 5413. The molecular results from the specimen from Leiria of the partial COI gene sequence show that M. conspersella is the closest related species (uncorrected p-distance 4.4 %) followed by M. servella and M. tetragonella with sequences available with 4.9 % and 5.7 % divergence, respectively.

Bionomics.

Collection dates for M. monellii sp. nov. are between 13 July and 3 September. The habitat is a roadside with limited vegetation near a small lake which is gradually silting up. The coastal forest is mainly composed of Pinus pinaster Aiton. The sandy soil has a variety of shrubs including species of Erica L. , Cistus L. , Halimium Spach and Corema album (L.) D. Don with scattered larger shrubs such as Morella faya (Aiton) Wilbur , Rhamnus alaternus L., Arbutus unedo L. and Salix repens L. Herbaceous plants include Juncus L. spp., Ammophila arenaria (L.) Link , Elymus L. sp., Silene littorea Brot. , Iberis procumbens Lange , Seseli tortuosum L. and Asphodelus L. From March onwards, coinciding with the beginning of the corresponding flowering, scattered clusters of Lysimachia monelli (L.) U. Manns & Anderb. are visible. It was on this plant that several pupae of M. monellii . were found which suggests that this is its host-plant. The pupae were found under the sandy soil, inside a silk tunnel, approximately one centimetre long, attached to the plant along the transition area between the stem and the root. No signs of stem mining were detected in any plants that were examined. This suggests that the larva feeds on upper parts of the plant and then descends to pupate at the base of the stem.

Etymology.

Monochroa monellii sp. nov. is named after its host-plant Lysimachia monelli (L.) U. Manns & Anderb. It is appropriate to mention here that the genus Lysimachia has recently been expanded to include species that were placed in Anagallis L. and Glaux L. ( Manns and Anderberg 2009).

Figures

Figure 1. Monochroa monellii sp. nov. holotype male, Lagoa de São José, Leiria, Portugal, 18. vi. 2025, leg. J. Rosete, gen. prep. J. Rosete JR 860 m. Right: Labels of holotype. Photograph by André Lameirinhas.

Figure 2. Monochroa monellii sp. nov. paratype female, Lagoa de São José, 29. vii. 2020, leg. J. Rosete, gen. prep. M. Dale MD 02977 f. Photograph by André Lameirinhas.

Figure 3. Monochroa conspersella (Herrich-Schäffer, 1854), Schleswig-Holstein, Germany, without locality, 25. vi. 1959, ex larva. (ECKU). Photograph taken by Mona Dahmen, made available by Hartmut Roweck in Gregersen and Karsholt (2022).

Figures 6–9. Male genitalia. 6. Monochroa monellii sp. nov., paratype male, Lagoa de São José, Leiria, Portugal, 29. vii. 2020, leg. J. Rosete, gen. prep. M. Dale MD 02981 m. Photograph by M. Dale. 7. Monochroa conspersella (Herrich-Schäffer, 1854), male, Őrség National Park, Hungary, 24. viii. 2023, leg. P. Davey, gen. prep. P. Hall. Photograph by P. Hall (Wheeler et al. 2025). 8. Monochroa servella (Zeller, 1839), male, Maria Ansbach im Wienerwald, Austria, 13. vi. 2014, leg. P. Buchner, gen. prep. PB 2214. Photograph by P. Buchner. 9. Monochroa tetragonella (Stainton, 1885), male, Hollesley, Suffolk, England, 29. vi. 2018, leg. and gen. prep. R. A. Watson Photograph by R. A. Watson.

Figures 10, 11. Female genitalia. 10. Monochroa monellii sp. nov., paratype female, Lagoa de São José, Leiria, Portugal, 29. vii. 2020, leg. J. Rosete, gen. prep. M. Dale MD 02979 f, photograph by M. Dale. 11. Monochroa conspersella (Zeller, 1839), female, Gorička National Park, Slovenia, 28. v. 2023, leg. P. Davey, gen. prep. P. Hall, photograph by P. Hall (Wheeler et al. 2025).

Figures 4, 5. Imagoes. 4. Monochroa servella (Zeller, 1839), male, Maria Ansbach im Wienerwald, Austria, 13. vi. 2014, leg. P. Buchner. Photograph by P. Buchner. 5. Monochroa tetragonella (Stainton, 1885), female, Hollesley, Suffolk, England, 6. viii. 2025, leg. R. A. Watson. Photograph by R. Watson.

Figures 12, 13. Female genitalia. 12. Monochroa servella (Zeller, 1839), female, Sweden, gen. prep, HH 1737 (ZMUC). 13. Monochroa tetragonella (Stainton, 1885), female, Denmark, gen. prep. HH 1440 (ZMUC). Photos from preparations of Henning Hendriksen, taken by Reinhard Sutter and published in Gregersen and Karsholt (2022).