Rhamma eleonorae Prieto, Álvarez & Clavijo, 2020

Prieto, Carlos, Hincapie, Carlos Federico Álvarez, Giraldo, Alejandra Clavijo & Uribe, Sandra, 2020, DNA barcodes, morphology and geographic distribution confirm a new butterfly species in the genus Rhamma (Lepidoptera: Lycaenidae), Zootaxa 4821 (1), pp. 181-188 : 182-185

Rhamma eleonorae Prieto, Álvarez & Clavijo new species

( Figures 5 , 8 )

Type material. Holotype female: COLOMBIA, Antioquia, Belmira, Páramo de Belmira , 3100m, 07/01/2011, specimen number: m1314, C. Prieto. The holotype is currently being deposited in RCCP, to be deposited in ICN-MHN.

Paratypes: 2♀ MEFLG: NC48160 , BMC-22363 IAvH-E-153322 , NC-48161 , BMC-22302 IAvH-E-153323 , 21/12/2013, 19/12/2013, COLOMBIA, Antioquia, Belmira, Páramo de Belmira, Malvazá , 3227m, F. Álvarez . 1♀ MEFLG: NC48162 , BMC-16124 , COLOMBIA, Antioquia, Belmira, Páramo de Belmira, Santa Ines , El Morro, 2718m, A. Clavijo-G Leg. 1♀ MEFLG: NC-48163 , BMC-18187 , COLOMBIA, Antioquia, Belmira, Páramo de Santa Ines, Montañitas 2, 2800m, A. Clavijo-G .

Diagnosis. This new species belongs to Rhamma because it shares the following combination of characters in the female genitalia with all other Rhamma species (see Prieto and Vargas 2016): 1) ductus bursae short and robust with a central transparent area, 2) strongly developed lamella postvaginalis, terminating in serrate, or multi-pronged configurations, 3) dendritic, fan shaped signa, and 4) a ventral element associated with the 8th tergite in female genitalia.

Females of Rhamma eleonorae sp. nov differs from females and males of R. oxida ( Figs. 1-5 ) in having a completely brown dorsal forewing surface, some blue scales can be seen just under microscope in the basal area of the wing. Additionally, R. eleonorae sp. nov is consistently smaller than R. oxida and R. arria , the later species having more extended blue suffusion in the female and male forewings than R. eleonorae sp. nov. Ductus bursae and lamella postvaginalis differ as illustrated ( Figs. 6-8 ).

Female Description. Adult female wings. Mean forewing length 10.5 mm (measured from forewing apex to base at thorax. n = 5). The hindwing anal angle is pointed without tail at vein Cu2. The dorsal wing surface is homogeneous brown with some orange scaling in anal angle. The ventral hindwing surface is reddish brown with a thin red sub-marginal band composed by six V shaped elements. Discal margin of hindwing is well defined and composed by ocher coloured scales.

Adult female body: The thorax and abdomen are covered with brown and dark gray scales.

Female genitalia: See diagnosis and Figure 8 .

Male. Unknown.

Etymology. This butterfly is named in honor of Eléonore Lipski, as suggested by Mireille Delprat through the BIOPAT initiative, in recognition of her support of biodiversity research and conservation of Neotropical butterflies. The specific epithet is a noun in the genitive case derived from the personal name Eléonore.

Biology. Females were captured on flight on vegetation and isolated bushes to near the ground in the páramohigh Andean forest ecotone. The females appear to display more activity in the morning around 10:00–12:00 hours on the sunny edges of paths or ridge tops. The immature stages, larval food plants, and adult nectar sources are unknown. Adults were captured during the months of May–July and November–December.

Distribution. The species is known from the type locality in the central mountain range of the Colombian Andes, between 2700 and 3100 m of altitude.

Discussion and remarks. In 2011, the senior author captured the first female specimen of this new species in the Belmira paramo. It was not taken into account in the taxonomic review of the genus Rhamma from Colombia, because the authors wanted to discard the hypothesis that it was a subspecies of Rhamma arria , one of the most widely distributed and variable species of the genus ( Prieto and Vargas 2016). After several attempts to find more specimens at the type locality or in entomological collections, we were able to locate four futher female individuals in the MEFLG and use all of them for the diagnosis of Rhamma eleonorae sp. nov., elevating the number of species for the genus in Colombia to 15. The species is diagnosed primarily on the basis of female characters. Description of new species based on male specimens is preferable in genera in which it is difficult to associate males and females ( Robbins 2004a), however, the wing pattern and COI sequences of the females of this new species are so divergent from its closest relatives that there is no doubt about its taxonomic validity. The species is easily distinguishable from the documented female variation in Rhamma arria and other species in the genus (see Prieto and Vargas, 2016).

Unfortunately, we did not manage to capture males, but the discovery of several typical specimens of Rhamma arria in the same mountain massif, and just 20 km from the place where Rhamma eleonorae sp. nov. was collected, indicating that these two species fly in sympatry without any evidence of intergradation, allowing us to reject the hypothesis that Rhamma eleonorae sp. nov is a subspecies of Rhamma arria .

Based on the NJ analysis, a typical Rhamma arria specimen collected at Belmira paramo was grouped with the typical Rhamma arria coming from other regions in Colombia and Perú ( Figure 9 : PLCOL010-19 BIN: ABX0547).

Differentiation between the new species and R. arria was clear. The sequences of two individuals of R. eleonorae sp. nov from the MEFLG exhibited an average genetic divergence with Rhamma arria of 4.5%. In the NJ tree Rhamma oxida is the closest relative of the new species with a divergence of 2.1% ( Table 1 , Figure 9 ).

As noted by Prieto and Lorenc-Brudecka (2017) and Prieto et al. (2018), the percentage of obviously different morphological species grouped within the same BIN is particularly high in the genus Rhamma . This is probably due to the fact that most of the species in the genus represent recently separated lineages that are still undergoing genetic differentiation and, in some cases, could represent mitochondrial introgression. Those studies and the present one reveal that DNA-based taxonomy can facilitate the process of identifying the diversity of the genus Rhamma , but, DNA barcode data may have some limitations to identify or circumscribe butterfly species of high elevations in the Andean ecosystems in absence of a deep ecological, morphological and taxonomic knowledge of the studied group.

Figures

FIGURE 9. Neighbor Joining identification tree. Rhamma eleonorae sp. nov sequences are denoted as: Rhamma sp 1 BMC16124 and 22302. Note the placement of Rhamma arria from Llanos de Cuiva. The distances were computed using the Kimura 2-parameter method (Kimura 1980) and are in the units of the number of base substitutions per site. The analysis involved 42 nucleotide sequences. All positions containing gaps and missing data were eliminated. There were a total of 577 positions in the final dataset. Analyses were conducted in MEGA7 (Kumar et al. 2016).

FIGURES 1-5. Rhamma adults from Colombia. 1, Rhamma arria male, Llanos de Cuiva; 2, Rhamma arria female, Cordillera Occidental; 3, Rhamma oxida male, Cauca; 4, Rhamma oxida female, Cauca; 5, Rhamma eleonorae sp. nov., female Holotype.

FIGURES 6–8. Rhamma female genitalia from Colombia. 6, Rhamma arria female, Cordillera Occidental; 7, Rhamma oxida female, Cauca; 8, Rhamma eleonorae sp. nov., female Paratype.