Icimauna espinozai, Santos-Silva, Antonio & Perger, Robert, 2017

Santos-Silva, Antonio & Perger, Robert, 2017, A new Icimauna Martins & Galileo, 1991, from the Bolivian orocline (Coleoptera, Cerambycidae, Lamiinae, Hemilophini), Zootaxa 4250 (5), pp. 489-493 : 489-491

Icimauna espinozai sp. nov.

( Fig. 2 A–D)

Description. Male. Integument black; ventral side of head reddish-brown; mouthparts reddish-brown with pale yellow palpi; anteclypeus and labrum reddish-brown; elytra yellowish-brown on basal 2/3 except black central area (wider on basal third); coxae and trochanters reddish-brown; pro- and mesofemora yellowish-brown with black apex; metafemora with basal third yellowish-brown and remaining surface black; protibiae reddish-brown on ventral side of basal third.

Head. Frons with yellow pubescence covering integument, interspersed with long, erect yellow setae close to eyes. Vertex finely, abundantly punctate; with longitudinal band of yellow pubescence from antennal tubercles to prothoracic margin (centrally forming slight crest from posterior ocular edge to prothoracic margin), laterally with yellowish-brown pubescence not obscuring integument. Antennal tubercles with dark brown pubescence not obscuring integument. Area behind eyes finely, abundantly punctate, mainly close to eye; with longitudinal band of yellow pubescence at area of connection of lobes; remaining surface with yellowish-brown pubescence not obscuring integument except yellowishwhite pubescence close to distal area of lower eye lobe, involving inferior side of lobe on gena. Distal area of genae glabrous. Postclypeus with sculpture and pubescence as on frons on basal area, smooth, almost glabrous toward apex; with some long, erect yellow setae. Labrum coplanar with anteclypeus on basal third, inclined on distal 2/3; with long, erect, moderately sparse yellow setae. Gulamentum nearly smooth and glabrous. Distance between upper eye lobes 0.15 times length of scape; distance between lower eye lobes in frontal view 0.60 times length of scape. Antennae 1.5 times elytral length, reaching elytral apex at basal quarter of antennomere X; scape, pedicel and antennomeres III–IV with short, dense, bristly black setae throughout (gradually shorter toward apex of IV); ventral side of scape, pedicel and antennomeres III–X with long, erect black setae (gradually sparser toward X); antennal formula (ratio) based on length of antennomere III: scape = 0.81; pedicel = 0.24; IV = 0.90; V = 0.70; VI = 0.57; VII = 0.57; VIII = 0.47; IX = 0.43; X = 0.41; XI = 0.49.

Thorax. Prothorax subcylindrical, slightly wider than long (1.10 times). Pronotum moderately finely, abundantly punctate; basal quarter with transverse, wide sulcus; central area of base with subdiamond gibbosity; central area with elongated gibbosity, more distinct close to basal transverse sulcus; laterocentral area with slightly distinct rounded gibbosity; sides with wide band of yellow pubescence obscuring integument, slightly tapering toward distal margin; central area with large, triangular macula of yellow pubescence obscuring integument (centrally forming slightly crest), distinctly narrowed from distal to basal margin; area between yellow bands with ochraceous pubescence gradually obscuring integument from base to apex. Sides of prothorax moderately coarsely, abundantly punctate; with yellowishwhite pubescence not obscuring integument, except pale yellow pubescence close to prosternum; with some long, erect, yellow setae. Prosternum moderately coarsely, sparsely punctate; sides with dense pale yellow pubescence, gradually sparer toward center (notably on area close to distal margin). Ventral side of meso- and metathorax with yellowish-white pubescence not obscuring integument; sides of metasternum finely, moderately sparsely punctate. Scutellum with yellowish-white pubescence partially obscuring integument. Elytra. Moderately coarsely, abundantly punctate (punctures slightly finer toward apex, aligned laterally from base to distal third and entire central region); area between rows of punctures slightly elevated; basal third with wide central band of grayish-white pubescence (more yellowish depending on angle of light) not obscuring integument; distal third with grayish-white pubescence not obscuring integument; central third with narrow band of grayish-white pubescence connecting central band of base to distal third; remaining surface of basal 2/3 with yellow pubescence not obscuring integument, except 4 longitudinal bands with dense crest-shaped pubescence. Legs. Femora with yellowish-white pubescence not obscuring integument, interspersed with long yellow setae on basal third of ventral side. Tibiae with long, erect, thick black setae (longer and more abundant dorsally). Metatarsomere I slightly shorter than II–III together.

Abdomen. Ventrites with yellowish-white pubescence not obscuring integument, interspersed with sparse, long, erect yellowish-white setae; apex of ventrite V centrally widely emarginate.

Dimensions. Total length, 7.4; prothorax: length, 1.1; anterior width, 1.2; posterior width, 1.1; humeral width, 1.7; elytral length, 5.6.

Type material. Holotype male from BOLIVIA, Santa Cruz: La Guardia ( Chiquitano forest ; 17°52’59”S / 63°19’04”W; 480 m a.s.l.), XI–XII.2015, beating tray, R. Perger col. ( MZSP) . Paratype male from BOLIVIA, Santa Cruz: 5 km SSE Buena Vista, Hotel Flora & Fauna (17°29’96”S / 63°39’13”W, 440 m a.s.l., on flowers of “ Sama Blanca Chica ”), 01.XII.2007, Clarke & Zamalloa col. ( RCSZ) .

Remark. The host flower “Sama Blanca” is Cupania cinerea Poeppig & Endl. (Family Sapindaceae ) (R. Clarke, pers. comm.).

Etymology. The species is named in honor of Dr. Juan Carlos Espinoza, who owns and has protected the forest in La Guardia for the last 30 years, and who also granted us permission to conduct research on his land.

Ecological distribution. Icimauna espinozai sp. nov. has been collected from sub-Andean Amazon (Buena Vista) and Chiquitano (La Guardia) forest at the Bolivian orocline in Santa Cruz department ( Fig. 1 C).

The mean annual rainfall in Buena Vista amounts to 2,101 mm with a mean annual temperature of 24.1°C ( Abrahamczyk et al. 2013). Navarro & Ferreira (2011) made reference to the forest in Buena Vista as pluviseasonal sub-Andean Amazon forest with the indicator tree species Swietenia macrophylla King 1886 (Meliaceae) and Terminalia oblonga (Ruiz & Pavón) Steudel (Combretaceae) .

The average annual precipitation in La Guardia is 1,085 mm with a mean annual temperature of 24.1°C (data for the close city of Santa Cruz, Abrahamczyk et al. 2013). According to the biogeographical regionalization by Navarro & Ferreira (2011), the ecosystem in La Guardia is considered as mesophytic-phreatophytic Chiquitano forest of the alluvial plains of Santa Cruz department. Tree indicator species for this ecosystem are Albizia niopoides (Spruce ex Bentham) Kuntze and Gallesia integrifolia (Sprengel) Harms ( Navarro & Ferreira 2011) .

Because both locations are close to or in a transition between sub-Andean Amazon and Chiquitano forest ( Fig. 1 C), it is difficult to determine if Icimauna espinozai sp. nov. is more closely related to one of both forest types. Additionally, both ecosystems may contain elements from the relatively close Andean forests in the west and subtropical deciduous Gran Chaco forests in the south (see Fig. 1 C).

Remarks. The holotype male of Icimauna espinozai sp. nov. differs from the males of the other species of the genus, excepting I. pallidipennis Martins & Galileo, 2007 , by the antennomere III only slightly longer than IV (notably longer in the males of the other species). It differs from I. pallidipennis as follows: central area of vertex with narrow longitudinal band of yellow pubescence; pronotum with distinct longitudinal areas of yellow pubescence; central area of basal 2/3 of the elytra dark and distal third entirely dark; elytral punctures finer and partially obliterated by pubescence. In I. pallidipennis , the central area of vertex with wide band of yellow pubescence covering nearly all surface, pronotum without bands of yellow pubescence, elytra slightly darker only on extreme apex, and the elytral punctures are coarser and not obliterated by the pubescence.

Mimicry. Over 200 species of Cerambycidae in 21 tribes are suggested to mimic species of the beetle family Lycidae ( Linsley 1961) . In species of Icimauna , the body color along with a slender habitus and apically less extended elytra mostly resemble species of the Lycidae genera Emplectus Erichson, 1847, Lycomorphon Pic, 1922 , Macrolygistopterus Pic, 1929 , Metapteron Bourgeois, 1905 , or Mesopteron Bourgeois, 1905 , which are all present in the Neotropics. Because the second author was not aware of the significance of the discovery of Icimauna espinozai sp. nov. and its mimicry during the field work of the current study, Lycidae species were not systematically sampled. Nevertheless, one of the few Lycidae that were collected in the habitat of I. espinozai sp. nov., most likely a species of Emplectus sp. (E. Nascimento, pers. comm.), had a similar body length and shape and color pattern ( Fig. 2 E) and may represent a model for I. espinozai sp. nov. The long hairs on the antennae of the latter may mimic the serrated antennae of the Emplectus sp. Further collecting is needed to assess if there are other sympatric Lycidae models that resemble more closely to I. espinozai sp. nov.

Figures

FIGURE 1. A, South America, image derived from Natural Earth World physical map with shaded relief at 1.24 km resolution (http: / / www. naturalearthdata. com); B, Bolivia; study area indicated by black square; C, ecosystems at the Bolivian orocline, Santa Cruz department, Bolivia; map derived from the shapefile of the biogeographical regionalization by Navarro & Ferreira (2011), using the Geographic Information System QGIS 2.14 (available at http: // www. qgis. org / en / site /); Collection location of holotype (La Guardia) indicated by red point, of paratype (Buena Vista) by red square; AN, Anthropogenic habitat; AF, Amazon rainforest; CF, Chiquitano forest; GC, Gran Chaco forest; TF, Bolivian Tucuman forest; Y, Bolivian Yungas forest.

FIGURE 2. Icimauna espinozai sp. nov., holotype male: A, dorsal habitus; B, ventral habitus; C, lateral habitus; D, head, frontal view. E, Emplectus sp., putative Lycidae model of I. espinozai sp. nov.