Embates tetrastigma (Champion)

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

20. Embates tetrastigma (Champion)

(Fig. 86–88, 249)

Ambates tetrastigma Champion 1907: 162 . Holotype, sex not determined, Panama, labeled “sp. figured”, “Type”, “Bugaba/ 800–1500 ft ” (BMNH). O’Brien & Wibmer 1982 (cat.); Hustache 1938 (cat.)

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

Redescription. Habitus: Similar to Fig. 81, total length 4.4–5.7 mm (m=5.2, n=10). Color: integument piceous, rostrum, legs and antenna variously rufous; ochreous scales in broad dorsolateral pronotal vitta and prevailing on elytron, scales black in elytral macula and on subapical callus (Fig. 86); venter with yellow scales except medially. Head: frontal fovea absent, rostrum moderately stout, subcylindrical, with sides slightly attenuated between apex and antennal insertion, curved (similar to Fig. 82), costate dorsomedially, basolateral margin produced, length of rostrum ♂♂ 1.11–1.26 x (m=1.16, n=9), ♀ 1.21 x (n=1) pronotal length, length of ante­antennal portion ♂♂ 0.34–0.37 x (m=0.36, n=9), ♀ 0.39 x (n=1) total rostral length, dorsal margin of antennal scrobe reaching rostral base before eye; length of funicular segments 1 and 2 subequal, club oblong ovate. Pronotum: length 0.90– 0.97 x (m=0.93, n=10) maximum width, sides rounded, widest in basal half, anterior portion tubulate; punctation dense and confluent, intervals granulose. Elytra: length 1.75–1.89 x (m=1.81, n=10) width at humeri, width 1.26–1.38 x (m=1.33, n=10) maximum pronotal width, sides subparallel in basal half, then increasingly narrowed toward apex, apices rounded conjointly, preapical callus moderate, striae fine, punctures indistinct, interstriae flat, 9 subcostate. Legs: tibiae nearly straight, ventrodistally with indistinct fringe (♂♂) or cluster (♀♀) of yellow hairs, protibial mucro notably produced in males, tarsal claws arcuate and separate at base. Male: apex of aedeagus broadly rounded, notched, incompletely fused medially, anterolateral portion more or less sclerotized (Fig. 87), body of aedeagus of moderate size, angular in basal third, apodemes 2.7 x longer than body of aedeagus, flagellum very thin, as long as aedeagus, transition to curved base gradual, basal appendage slender, imperfectly fused subdistally with base of flagellum, projecting beyond base (Fig. 88).

Plant association. Piper nudifolium (Prena 12).

Distribution. Costa Rica and Panama, Pacific side of Cordillera de Talamanca (Fig. 249).

Material examined. COSTA RICA. Puntarenas: 4 km S San Vito , 1100 m ( HAHC, JPPC) ; Osa, P.N. Corcovado , 100–300 m ( CHAH, HPSC, JPPC 8 ) ; 24 km W Piedras Blancas , 200 m ( CWOB) . San José: 12 km NE San Isidro, Cerro Chucuyo , 1350 m ( JPPC 2 ) . PANAMA. Chiriquí: Bugaba ( BMNH) . Total 16 specimens.

Discussion. Embates tetrastigma is related very closely to E. sinuatus (see discussion there). Both species co­occur on the Pacific side of the Cordillera de Talamanca, where they are associated with different hosts. Without genital dissection, they can be distinguished readily by their color­patterns. However, it should be kept in mind that this pragmatic character state should be used with caution (see discussion of E. belti and E. triangularis ).