Pelmatellus amicorum Delgado and Ruiz-Tapiador, new species

Zoobank.org/ urn:lsid:zoobank.org:act: A8ACC4C1-EF2F-437D-9976-D1D30E926366 (Figs. 1, 2)

Type Material. Holotype ♂. Alto Salcedo (Puno) 15°53 ' 33 " S, 70°00 ' 53 " W, 4,023 m, 09/12/ 2016, P. Delgado leg. (NHMLP). Paratypes: Alto Salcedo (Puno) 15°53 ' 33 " S, 70°00 ' 53 " W, 4,023 m, 09/12/2016, P. Delgado leg., 4 ♂♂ and 4 ♀♀ (NHMLP), 6 ♂♂ and 6 ♀♀ (CPD), 20 ♂♂ and 34 ♀♀ (ELAESI); Batalla (Chucuito) 16°19 ' 33 " S, 69°14 ' 50 " W, 3,880 m, P. Delgado leg., 27/03/2012, 2 ♀♀ (ELAESI); Bellavista (San Antonio de Putina) 14°36 ' 11 " S, 69°58 ' 19 " W, 4,050 m, 17/11/2009, P. Delgado leg, 1 ♂ and 1 ♀, (OUMNH); Cabana (San Román) 15°39 ' 07 " S, 70°18 ' 53 " W, 3,925 m, 13/10/ 2017, P. Delgado, 1 ♀, (ELAESI); Calacota (El Collao) 16°02 ' 58 " S, 69°36 ' 34 " W, 3,841 m, 03/02/ 2013, P. Delgado leg., 10 ♂♂ and 24 ♀♀ (ELAESI); Camacani (Puno) 15°52 ' 09 " S, 69°54 ' 36 " W, 3,835 m, 21/10/2010, P. Delgado leg., 13 ♂♂ and 21 ♀♀ (ELAESI); Cancharani (Puno) 15°50 ' 39 " S, 70°12 ' 50 " W, 4,280 m, 06/11/2009, P. Delgado leg., 1 ♂ and 11 ♀♀ (ELAESI); Capachica (Puno) 15°38 ' 30 " S, 69°49 ' 50 " W, 3,835 m, 05/01/2016, P. Delgado leg., 2 ♀♀ (ELAESI); Caritamaya (Puno) 16°00 ' 06 " S, 69°49 ' 12 " W, 3,854 m, 10/11/2017, P. Delgado leg., 1 ♂ and 1 ♀ (ELAESI); Catahuichinca (Puno) 16°11 ' 10 " S, 69°44 ' 29 " W, 3,877 m, 09/11/ 2010, P. Delgado leg., 1 ♀ (ELAESI); Chatuma (Chucuito) 16°21 ' 25 " S, 69°18 ' 10 " W, 3,880 m, 13/01/2010, P. Delgado leg., 3 ♂♂ and 12 ♀♀. (ELAESI); Chinchera (Puno) 15°50 ' 18 " S, 69°55 ' 19 " W, 3,854 m, 21/10/2010, P. Delgado leg., 1 ♀ (ELAESI); Chinumani (Yunguyo) 16°18 ' 36 " S, 69°08 ' 45 " W, 3,868 m, 23/09/2010, P. Delgado leg., 1 ♀ (ELAESI); Chulluni (Puno) 15°48 ' 53 " S, 69°59 ' 31 " W, 3,822 m, 26/05/2015, P. Delgado leg., 3 ♂♂ and 11 ♀♀ (ELAESI); Cieneguillas (San Román) 15°41 ' 36 " S, 70°25 ' 26 " W, 3,889 m, 22/09/ 2015, P. Delgado leg., 3 ♀♀ (ELAESI); Collana (San Román) 15°18 ' 14 " S, 70°21 ' 36 " W, 3,895 m, 22/09/ 2015, P. Delgado leg., 3 ♂♂ and 5 ♀♀ (ELAESI); Cutimbo (Puno) 16°15 ' 33 " S, 70°06 ' 46 " W, 3,948 m, 29/10/2012, P. Delgado leg., 2 ♂♂ and 1 ♀ (NMNH); Huaje (Puno) 15°55 ' 10 " S, 69°59 ' 40 " W, 3,820 m, 26/05/2015, P. Delgado leg., 4 ♀♀ (ELAESI); Huancho (Huancané) 15°13 ' 46 " S, 69°54 ' 38 " W, 3,902 m, 17/12/2014, P. Delgado leg., 1 ♀ (ELAESI); Huaycho (El Collao) 16°03 ' 51 " S, 69°34 ' 21 " W, 3,844 m, 18/11/2009, P. Delgado leg., 3 ♂♂ and 4 ♀♀ (NMNSM), 2 ♂♂ and 5 ♀♀ (CIRT); same localit, 20/01/2010, P. Delgado leg., 1 ♂ and 3 ♀♀ (NMNH), 3 ♂♂ and 3 ♀♀ (BMNH), 1 ♂ and 4 ♀♀ (OUMNH), 1 ♂ and 6 ♀♀ (CIRT); Illpa (Puno) 15°56 ' 46 " S, 70°16 ' 53 " W, 3,815 m, 16/11/2009, P. Delgado leg., 1 ♂ (OUMNH), 10 ♀♀ (CIRT); La Calera (Lampa) 15°21 ' 33 " S, 70°22 ' 21 " W, 3,881 m, 27/10/2010, P. Delgado leg., 3 ♂♂ and 14 ♀♀ (ELAESI); Lampa Grande (Chucuito) 16°44 ' 03 " S, 69°20 ' 29 " W, 3,947 m, 13/01/2017, P. Delgado leg., 1 ♀, (ELAESI); Ma ~ nazo (Puno) 15°46 ' 32 " S, 70°20 ' 28 " W, 3,923 m, 21/09/2010, P. Delgado leg., 5 ♀♀ (ELAESI); Mu ~ nani (Azángaro) 14°46 ' 08 " S, 69°57 ' 16 " W, 3,983 m, 18/12/2015, P. Delgado leg., 1 ♀ (ELAESI); Paucarcolla (Puno) 15°44 ' 46 " S, 70°03 ' 33 " W, 3,874 m, 20/10/2010, P. Delgado leg., 1 ♂ and 6 ♀♀ (ELAESI); Pisacoma (Chucuito) 16°54 ' 51 " S, 69°21 ' 38 " W, 3,904 m, 23/09/2010, P. Delgado leg., 1 ♀ (ELAESI); Pucará (Lampa) 15°02 ' 47 " S, 70°22 ' 12 " W, 3,897 m, 10/11/2011, P. Delgado leg., 4 ♂♂ and 5 ♀♀ (ELAESI); Puente Yanapampa (Huancané) 15°54 ' 31 " S, 69°25 ' 20 " W, 3,890 m, 17/12/2014, P. Delgado leg., 1 ♂ (ELAESI); Puerta del Diablo (Chucuito) 16°20 ' 21 " S, 69°35 ' 12 " W, 3,875 m, 16/12/2016, P. Delgado leg., 4 ♂♂ and 18 ♀♀ (ELAESI); Quenafaja (Puno) 16°08 ' 00 " S, 69°42 ' 04 " W, 3,844 m, 09/11/2010, P. Delgado leg., 5 ♂♂ and 12 ♀♀ (ELAESI); Salcedo (Puno) 15°39 ' 30 " S, 69°48 ' 21 " W, 3,832 m, 17/12/ 2016, P. Delgado leg., 7 ♂♂ and 40 ♀♀, (ELAESI); San Antón (Azángaro) 14°36 ' 55 " S, 70°22 ' 15 " W, 4,026 m, 18/12/2016, P. Delgado leg., 2 ♀♀, P. Delgado leg. (ELAESI); Siale (Puno) 16°39 ' 32 " S, 69°48 ' 01 " W, 3,833 m, 05/01/2016, P. Delgado leg., 1 ♂ and 6 ♀♀ (ELAESI); Sillustani (Puno) 15°43 ' 16 " S, 70°09 ' 30 " W, 3,901 m, 12/08/2010, P. Delgado leg., 1 ♂ and 9 ♀♀ (ELAESI); Tinajani (Melgar) 15°00 ' 58 " S, 70°34 ' 43 " W, 3955 m, 10/11/ 2015, P. Delgado leg., 6 ♀♀ (ELAESI); Totorani (Puno) 15°47 ' 41 " S, 70°09 ' 46 " W, 3,912 m, 26/05/ 2015, P. Delgado leg., 1 ♀ (ELAESI); Wilamaya (El Collao) 16°03 ' 12 " S, 69°31 ' 22 " W, 3,827 m, 10/11/ 2010, P. Delgado leg., 6 ♂♂ and 26 ♀♀ (ELAESI); Yarajcancha (San Román) 15°56 ' 33 " S, 70°37 ' 14 " W, 4,115 m, 01/04/2016, P. Delgado leg., 5 ♀♀ (ELAESI); Yunguta (El Collao) 16°03 ' 38 " S, 69°34 ' 48 " W, 3,853 m, 21/10/2009, P. Delgado leg., 3 ♀♀, (CIRT); same locality, 21/12/2009, P. Delgado leg., 2 ♀♀ (CIRT).

Description. Length 5.0–6.0 mm (Fig. 1), mean length slightly longer in females (5.3 mm) than in males (5.2 mm). Brachypterous. Blackish brown body with faintly shiny discal areas on the pronotum and elytra. Margins of pronotum and elytra paler, appendages testaceous. Integument in general microreticulated. Head: Wider (0.98 mm) than long (0.88 mm). Microsculpture well-developed around eyes and at base, usually very weakened or absent elsehwere on head. Antennae and labium without

special peculiarities within the genus. Cephalic setae composed of 3 labral pairs, 1 clypeal pair and 1 ocular pair. Cephalic appendages testaceous, with antennae darkened from the distal end of 3 rd antennomere to last antennomere. Pronotum: Transverse, wider (1.8 mm) than long (1.1 mm), anterior margin wider than basal margin and reaching maximum width in anterior half of pronotum. Lateral edge regularly arched and posterior angles rounded. Well-defined basal pits, oval shaped, with variable depth and visible reticulation inside. Elytra: Wide (2.2 mm), maximum width in posterior half. Striae well-marked, relatively wide. Third elytral interval with a discal pore in posterior half on medial side. Umbilicate series variable, between 11 and 14 punctures (4–5, 1, 6–8). Elytral disc usually with a weak greenish reflection and suture zone and lateral margins often reddish. Legs: Similar to other species of the genus. Male pro- and mesotarsi moderately dilated, ventral side densely covered in vestiture. Male genitalia: As in Fig. 2. Aedeagus relatively short, slightly raised at end and apex slightly thickened. Inner sac of aedeagus with 5 welldifferentiated pieces: a very long spine distally, 2 triangular pieces of more moderate size, and 2 squamous pieces arranged symmetrically. The morphology of the male genitalia presents a set of characters that are clearly different from other known species of the genus.

Taxonomic Considerations. Starting from the groups established by Moret (2000, 2005) (Table 1), P. amicorum matches the characteristics of the variipes species-group. It is a brachypterous species of medium size and with weak or no metallic reflection. The pronotum of P. amicorum is transverse, with arched sides and rounded posterior angles. Finally, the male mesotarsi are moderately dilated, and the presence of setae in the third elytral interval is compatible with the characteristics of the variipes species-group. Within the variipes species-group, P. amicorum presents a closer affinity with Pelmatellus caerulescens Moret, 2005, Pelmatellus variipes Bates, 1891, and Pelmatellus obesus Moret, 2000, due to the presence of punctures in the third elytral interval. However, the different external morphology of the aedeagus and the different configuration of the internal parts distinguish P. amicorum from them (Moret 2000, 2005).

Ecology. Pelmatellus is characterized by great ecological plasticity, which allows its species to occur in various ecosystems. Pelmatellus amicorum is commonly encountered between 3,815 and 4,280 m elevation. It inhabits xerophytic scrublands of the Peruvian Altiplano, although it has also been collected in hygrophilic conditions on the shores of lakes and streams or even in cultivated quinoa (Chenopodium quinoa Willd., Amaranthaceae) and potato (Solanum tuberosum L., Solanaceae).

Etymology. This species is dedicated to our friends (amicorum) Julio Sosa, Edwin Velásquez,

and Luis Luque, to thank them for their sampling work during many expeditions.

Distribution. Pelmatellus amicorum occurs in southern Peru (Map 1). Very little is known about the distribution of Pelmatellus in Peru. Only the general presence of Pelmatellus columbianus (Reiche, 1842) in Peru (Moret 2000, 2005; Perrault 1993), as well as the possible presence of Pelmatellus gracilis Moret, 2000, in the north (Moret 2000, 2005), Pelmatellus cycnus Moret, 2000 (Moret 2000), and Pelmatellus lojanus Moret, 2000 (Moret 2000), are known or speculated. Moreover, some authors, e.g., Erwin et al. (2015), have pointed out the existence of up to 12 new taxa not yet described. In any case, although P. amicorum is tentatively assigned to the variipes species-group, it should not be forgotten that the knowledge of the subgenus at the continental level is still little known. Undoubtedly, additional sampling together with the description of new taxa could affect the a subgeneric or species-group classification of Pelmatellus.