Embates thoracicus (Chevrolat)

Prena, Jens, 2005, The Middle American species of Embates Chevrolat (Coleoptera: Curculionidae: Baridinae), Zootaxa 1100 (1), pp. 1-151 : 1-151

23. Embates thoracicus (Chevrolat)

(Fig. 97–99, 261)

Ambates thoracicus Chevrolat 1877: 344 . Holotype female[?], Colombia, labeled: “Nov. Gren./ Magd.”, “Typus”, “ Ambates / thoracicus/ Chevr.”, “232/58” (NHRS). Champion 1907; Hustache 1938 (cat.); O’Brien & Wibmer 1982 (cat.); Wibmer & O’Brien 1986 (cat.)

Ambates vitticollis Chevrolat 1879 : CXLIX. Holotype sex not determined, Colombia, labeled: “Honda”, “Nova Grenada / J. Goudot ”, “ Paratypus ” [lapsus?], “ A. vitticollis / Chev N. Grenada ”, “ Ambates / vitticollis”, “234/58” (NHRS). Kuschel 1955 (synonymy)

Embates [ thoracicus ]. Alonso­Zarazaga & Lyal 1999 (global combination of all species of Ambates Schönherr 1836 with Embates Chevrolat 1833 )

Redescription. Habitus: Fig. 97, total length 4.1–5.7 mm (m=5.0, n=21). Color: integument black, partially piceous; basic vestiture of black scales, white and ochreous scales in apical portion of elytron, in broad dorsolateral and thin dorsomedian pronotal vittae, and some ventral and lateral portions. Head: frontal fovea absent, rostrum rather stout, subcylindrical, curved, subcostate dorsomedially, basolateral margin edged, length of rostrum ♂♂ 1.05–1.20 x (m=1.13, n=5), ♀♀ 1.08–1.23 x (m=1.15, n=16) pronotal length, length of ante­antennal portion ♂♂ 0.38–0.42 x (m=0.40, n=5), ♀♀ 0.41–0.45 x (m=0.43, n=15) total rostral length, dorsal margin of antennal scrobe reaching rostral base well before eye; length of funicular segments 1 and 2 subequal, club oblong ovate. Pronotum: length 0.78– 0.89 x (m=0.81, n=21) maximum width, sides rounded, greatest width close behind middle, anterior portion tubulate. Disk densely and shallowly punctate, intervals forming isolated granula. Elytra: length 1.64–1.82 x (m=1.70, n=21) width at humeri, width 1.21–1.30 x (m=1.25, n=21) maximum pronotal width, sides subparallel in basal half, then increasingly narrowed toward apex, apices rounded conjointly, preapical callus strongly produced, striae fine, punctures indistinct, interstriae flat, 9 subcostate. Legs: tibiae variously curved, expanded dorsoventrally (particularly in males), ventral margin slightly bisinuate, distally with fringe of hairs, tarsal claws small, subconnate at base. Male: apex of aedeagus round, middle sclerotized, anterolateral portion membranous (Fig. 98), body of aedeagus of moderate length, basal third angular in lateral view, apodemes 2.3 x longer than body of aedeagus, flagellum thin, half as long as apodemes, transition to curved base gradual, basal appendage moderate, fused subdistally with base of flagellum, projecting beyond base (Fig. 99).

Plant association. Piper marginatum (Prena 5)

Rearing records. Stem of Piper marginatum (Prena 1)

Distribution. Nicaragua to Brazil, moist situations of disturbed habitats (Fig. 261).

Material examined. NICARAGUA. Managua: El Crucero, 800 m ( JPPC, SEAN) . Rivas: Isla de Ometepe, Volcán Madera, 200 m ( JPPC 2 , SEAN) . COSTA RICA. Alajuela: Upala, Colonia Libertad, 450 m ( MUCR) . Guanacaste: Los Almendros, Guanacaste N.P. ( INBC) ; Cerro El Hacha , 600 m ( INBC) ; S Sta. Cecilia, Est. Pitilla, 700 m ( INBC) . Heredia: Puerto Viejo, Est. La Selva , 100 m ( INBC) . Puntarenas: Quepos , Manuel Antonio N.P., 80 m ( CNCI, JPPC) . San José: 2 km S Ciudad Colón , 1100 m ( HAHC, JPPC 2 ) . PANAMA. Canal Zone : numerous locations ( BMNH, CHAH 4 , CMNC 3 , CNCI, FAUP, FOEC 3, GBFM 4, HPSC 10, JPPC, NMNH 15 , TAMU 2 ) . Coclé: El Valle, 650–700 m ( HPS 2 , BMNH) . Colón: Gatun Lake , north shore ( CMNC) ; Portobelo ( NMNH 18 ) . Darién: Cana, 450 m ( HPSC 4 ) ; Río Tuquesa , 20 m ( HPSC) ; Villa Darién ( GBFM) . Los Santos: Cerro Canajagua, 800 m ( HPSC) . Panamá: Cerro Campana, 800–850 m ( HPSC 4 , NMNH) ; Ipetí , 150 m ( HPSC) ; Chepo, Altos de Majé ( HPSC 5 ) ; Llano­Carti rd. km 9, 350 m ( HPSC 2 ) ; Isla Taboga ( BMNH, NMNH 2 ) . COLOMBIA. Río Magdalena ( NHRS) . Cundinamarca: Bogota ( MNHP) ; Villeta ( CWOB) . Nariño: Pasto ( NMNH) . Without location ( BMNH 3 , MLUH, NMNH) . BRAZIL. Espírito Santo [on Río Ica ?] ( MNHP 2 ) . Total 91 specimens .

Discussion. Embates thoracicus is related to E. tergosignatus and E. apicalis , and can be distinguished from those by its predominantly black vestiture and the notably produced preapical callus. The species appears to be absent in most areas of the Atlantic side of the Cordilleras Central and Talamanca. The distribution matches well with that of its primary host, Piper marginatum , a common plant in weedy habitats and in moist situations of deciduous dry forests between Guatemala and Brazil ( Burger 1971). The discontinuity in the distributional records between central Panama and northwest Costa Rica (Fig. 261) may have resulted from incomplete sampling.