Thereus borbaensis Faynel, O’Brien & Fåhraeus, 2025

Faynel, Christophe, Huertas, Blanca, Crom, Jean-François Le, O’Brien, Richard & Fåhraeus, Christer, 2025, Diagnostic male secondary sexual structures and wing patterns in the Thereus genena species group (Lepidoptera: Lycaenidae: Theclinae) with the description of nine new species from Colombia, Peru, Brazil and French Guiana, Zootaxa 5728 (2), pp. 201-246 : 225-226

Thereus borbaensis Faynel, O’Brien & Fåhraeus sp. nov.

LSIDurn:lsid:zoobank.org:act: 029D16BE-3120-4C9E-BA48-6EB335975909

Figures 14 , 41 , 57 , 88

Type material. Holotype male ( Fig. 14 ), FW: 16.1 mm, labelled as “Borba // VI.1932 ”; “Gen. prep. Klaudia Florczyk” (green rectangular label, black printed); “ Holotype ♂ // Thereus borbaensis // Faynel, O’Brien & Fåhraeus, 2025” (red rectangular label, black printed); “SMF-L 4800” (white rectangular label, black handwritten). Borba is a town on the Madeira River , south of Manaus, Amazonas, Brazil ( 4°23′16″S, 59°35′38″W). The holotype is in the SMF collection.

Paratypes ( 2♂). BRAZIL. Amazonas. 1♂, Olivenca, H Bre, MFN-LEP-1441* ( MfN) . 1♂, Maués, Rio Preto , xi. 2007, local collector, Coll. A. Moser 779 ( AMC) .

" Olivenca" is São Paulo de Olivença in Amazonas, Brazil ( 3°27′34″S, 68°56′0″W) which is near Colombia and Peru borders and 100 km West from the town of Borba (Amazons department) .

The paratype now has added the following labels “ Paratype ♂ // Thereus borbaensis // Faynel, O’Brien // & Fåhraeus, 2025” (blue rectangular label, black printed).

Diagnosis and description. Thereus borbaensis sp. nov. is close phylogenetically ( Fig. 1 ) to T. antecum sp. nov. but it is easily distinguished by its double androconia (scent patch + scent pad) whereas T. antecum sp. nov. only have one scent pad on male DFW. This distinction is corroborated by a mean genetic divergence of 6.81% ( Table 3). T. borbaensis sp. nov. is also close externally to T. chontachaca sp. nov. and T. ramirezi sp. nov. but differs from them by: (1) much larger black scent patch on male DFW, filling more than half of the discal cell ( Figs 41-43 ); (2) dorsal blue less dull dorsally and more extended on male DFW ( Figs 14-16 ); (3) penis convex ( Fig. 37 , black arrow), while it is straight or arched in the others; (4) 4.22 % mean genetic distance with T. chontachaca sp. nov., and 4.96 % with T. ramirezi sp. nov. ( Table 3). Male ( Fig. 14 ). FW length: 15.8 mm (n = 2). Wings. DFW blue covering a large part of the wing; huge oval black scent patch, filling almost all discal cell; oval brown scent pad, one third smaller, located after the discal cell. Male genitalia ( Fig. 57 ). Similar to T. chontachaca sp. nov. in ventral view; but dorsal brush organs much longer in lateral view; penis dorsally concave (black arrow) while it is straight or angled in all other species of the genena group; eighth tergite subrectangular, with straight posterior border and curved anterior one. Female. Unknown.

Sympatry. T. borbaensis sp. nov. is allopatric with T. antecum sp. nov., T. chontachaca sp. nov. and T. ramirezi sp. nov. ( Figs 88, 89 ).

Known distribution ( Fig. 88 ). This uncommon species is known only from Brazil (AM).

Etymology. The name comes from the Brazilian town Borba. It is a latinized name considered as masculine.

Figures

FIGURE 1. Thereus genena species group, phylogenetic tree generated with IQ-Tree using 83 COI sequences. Each specimen has the following information (if available): scientific name, process ID, country, department. Type material in red. Method of construction of the tree: Maximum-Likelihood.

FIGURES 2–17. Adults of Thereus. 2. ♂ Thereus endera (ST, Brazil, NHMUK). 3. ♀ Thereus endera (ST, Thecla thestia, Brazil, NHMUK). 4. ♂ T. geminus sp. nov. (HT, Peru, NHMUK). 5. ♀ T. geminus sp. nov. (PT, Peru, RCCF). 6. ♂ T. cacao sp. nov. (HT, French Guiana, MNHN). 7. ♀ T. cacao sp. nov. (PT, French Guiana, RCCF). 8. ♂ T. antecum sp. nov. (HT, French Guiana, MNHN). 9. ♀ T. antecum sp. nov. (PT, French Guiana, RCCF). 10. ♂ Thereus genena (ST, Brazil, NHMUK). 11. ♀ Thereus genena (Brazil, NHMUK). 12. ♂ Thereus angulus stat. rev. (HT, Colombia, ICN-MHN). 13. ♂ Thereus angulus stat. rev. (Peru, RCCF). 14. ♂ T. borbaensis sp. nov. (HT, Brazil, SMF). 15. ♂ T. ramirezi sp. nov. (HT, Peru, NHMUK). 16. ♂ T. chontachaca sp. nov. (HT, Peru, MUSM). 17. ♀ T. chontachaca sp. nov. (PT, Peru, RCCF).

FIGURES 34–49. Male forewing androconia. 34. ♂ Thereus endera. 35. ♂ T. geminus sp. nov. 36. ♂ T. cacao sp. nov. 37. ♂ T. antecum sp. nov. 38. ♂ Thereus genena. ♂ 39. ♂ Thereus tiasa. 40. ♂ Thereus angulus stat. rev. 41. ♂ T. borbaensis sp. nov. 42. ♂ T. chontachaca sp. nov. 43. ♂ T. ramirezi sp. nov. 44. Thereus ortaloides stat. rev. 45. ♂ T. confusus sp. nov. 46. ♂ T. praxioides sp. nov. 47. ♂ Thereus praxis. 48. ♂ Thereus ortalus. 49. ♂ T. aguacatal sp. nov. Wings not at same scale for comparison purpose.

FIGURES 50–59. Male genitalia. From left to right: left lateral view with penis in place, left lateral view with penis and brush organs removed (at least one), ventral view and penis in lateral view above. Black arrows show diagnostic characters (see in the text). 50. Thereus endera. 51. Thereus geminus sp. nov. 52. Thereus cacao sp. nov. 53. Thereus antecum sp. nov. 54. Thereus genena. 55. Thereus tiasa. 56. Thereus angulus stat. rev. 57. Thereus borbaensis sp. nov. 58. Thereus chontachaca sp. nov. 59. Thereus ramirezi sp. nov. Scale bars: 1 mm.

FIGURES 88–89. Geographic distribution of the species of Thereus belonging to the genena group (question mark for imprecise data placed in the center of the province/state). 88. T. aguacatal sp. nov., T. borbaensis sp. nov., T. chontachaca sp. nov., T. ramirezi sp. nov. 89. T. antecum sp. nov., T. genena, T. tiasa.