Bhamoina varipes (Jacoby, 1884)

Prathapan, Kaniyarikkal D., Poorani, Janakiraman, Kumari, S. Amritha, Anuradha, C., Balakrishnan Padmanaban, & Thanigairaj, Ramalingam, 2019, Species composition and diagnoses of leaf- and fruit-scarring beetles (Coleoptera, Chrysomelidae) infesting bananas and plantains (Zingiberales, Musaceae) in the Indian subcontinent, Deutsche Entomologische Zeitschrift 66 (2), pp. 179-202 : 179

Bhamoina varipes (Jacoby, 1884) Figs 10 , 11 , 12

Eucycla varipes Jacoby, 1884: Jacoby 1884: 210 (Sumatra; Mus. Leiden); Duvivier 1885: 42 (Is. Bodjo).

Sphaeroderma varipes : Jacoby 1889: 193 (N Burma: Teinzo, Bhamo; Tenasserim: Meetan); Maulik 1926: 318, 328 (Burma: Karen Mts., Assam: Khasi Hills).

Bhamoina varipes : Bechyné 1958: 91; Scherer 1969: 202-203; Dӧberl 2010: 505.

Bhamonia [sic] varipes : Kimoto 2005: 80.

Sphaeroderma varipennis Jacoby 1892: 928 (Carin Cheba, Palon, Rangoon; Mus. Genova); Maulik 1926: 318, 325; Scherer 1969: 202 (synonymy).

Material examined.

Type material of Sphaeroderma varipennis Jacoby: "Type (H.T.) (red bordered circular label)/ Carin Cheba, 900-1100 m, L. Fea, v.XII.88 / Jacoby Coll. 1909-28a / Sphaerod. varipennis Jac. (blue label)" (BMNH); Others: "Sumatra/ Jacoby Coll. 1909-28a/ variepennis Jac. In B.M. Coll. C.M.F. Von Hayek det. 1967/ Bhamoina varipennis (Jacoby), G. Scherer det. 1967" (BMNH). India: Assam: 5♂, 6♀♀, Balipara 74 m msl; 26°49'56.0"N, 92°46'41.1"E; 17.V.2019; K. D. Prathapan Coll. (KAU); Meghalaya: 3♂, 8♀ Barapani 993 m msl; 25°41'17.6"N, 91°55'5.1"E; 5.vi.2013; K. D. Prathapan Coll. Ex banana (KAU); Meghalaya: 11♂, 16♀, Ri Bhoi Dst., Saiden 540 m msl; 25°52'41.0"N, 91°53'1.4"E; 4.vi.2013; K. D. Prathapan Coll. Ex banana (KAU); Meghalaya: 5♂, 2♀, Nongpoh, 587 m msl; 25°50'34.4"N, 91°52'34.4"E; 22.v.2019; K. D. Prathapan Coll. (KAU).

Remarks.

The genus Bhamoina closely resembles Sphaeroderma (see below for the generic diagnosis of Sphaeroderma ). Bhamoina acutangula (Jacoby), the type species of the genus, was originally described in Sphaeroderma . Bhamoina can be easily separated from Sphaeroderma by the anteriorly produced anterolateral corners of pronotum (in Sphaeroderma , the anterolateral corners of pronotum are not produced forward, or only slightly produced). Sphaeroderma varipennis Jacoby, treated as a synonym of B. varipes by Scherer (1969), is bicolored ( Fig. 11a ) with the eltyra fully black and the head and pronotum reddish. It has a slightly more robust body form, and the anterolateral corners of pronotum ( Fig. 11b, c ) are less produced and somewhat obtusely rounded compared to those of B. varipes .

Scherer (1969) gave a key to the Oriental species of Bhamoina . Sphaeroderma varipennis has been known to be a pest of banana in Thailand, and adults defoliate banana ( Hill 2008). Dean (1978) recorded " Sphaeroderma veripennis " on banana in Laos. Although B. varipes is distributed in India, there has been no previous records of its host plant association from India.

Description.

Entirely red-brown ( Fig. 10a, b ), except eyes and distal portion of mandibles black. Elytra darker in a few examples. Proximal 5-7 antennomeres lighter than distal ones. Anterolateral corners of pronotum, palpi, fore- and midfemora, tarsomeres, and last abdominal ventrites often lighter than dorsum.

Length 2.71-3.41 mm, width 1.97-2.80 mm, 1.34 × longer than broad. In lateral view vertex weakly convex, forming a concavity where it joins frons; frons strongly arched, joining clypeus at an obtuse angle. In frontal view vertex moderately flat, sparsely punctate with a mixture of small and minute punctures. Supraorbital pore circular, without shallow groove surrounding it, placed just above orbital sulcus, two or three smaller punctures anterior to supraorbital pore present. In frontal view ( Fig. 10c ), frontal ridge broad and raised between antennal sockets; narrowed dorsally entering between antennal calli; ventrally narrower than dorsally; frontolateral area anteriorly with a few setae; anterofrontal area flat, not forming ridge, with long and short setae. Antennal calli transverse-oblique, trapezoidal, slightly higher than vertex, narrowly separated dorsally; anteromesal ends acutely angulate, entering into interantennal space. Supracallinal sulcus deep, gently convex, oblique, narrower than orbital sulcus. Suprafrontal, supraorbital, supraantennal sulci well developed, all weaker than supracallinal sulcus. Distance between antennal sockets 1.57 × diameter of a socket, antennal sockets separated from adjacent eye by a distance 0.38 × transverse diameter of a socket. Labrum wider than long, dorsal surface convex anteriorly, anterior margin convex, with three pairs of labral setae arranged in a transverse row. First antennomere longer than second and third combined, second a little longer than third and fourth separately, sixth onwards antennomeres progressively thickened. Proportionate length of antennomeres I to XI: 1: 0.48: 0.41: 0.52: 0.56: 0.44: 0.59: 0.52: 0.52: 0.52: 0.8. Maxilla with penultimate palpomere thicker and longer than last and preceding palpomeres separately. Labium with penultimate palpomere thickened, subequal in length to thin, pointed last palpomere.

Pronotum ( Fig. 10d ) convex, distinctly narrowed anteriorly, 0.30 × as long as wide, posteriorly 1.65 –1.76× wider than anteriorly, profusely, uniformly covered with small punctures. Pronotal punctures as small as half of elytral punctures. Lateral margin weakly convex proximally, gently concave at anterolateral seta bearing pore; broader anteriorly than posteriorly. Anterior margin deeply concave, except gently convex in middle. Posterior margin bisinuate, forming a distinct lobe in middle. Anterolateral callosity ( Fig. 10e ) projecting forward on either side of head; seta bearing pore on dorsal posterior face of callosity. Posterolateral callosity not protruding laterally, with seta bearing pore on lateral face.

Scutellum triangular, acutely angulate posteriorly, shiny, flat on top, minutely punctate. Elytra as wide as pronotum at base, widened postbasally, lateral margin entirely visible in dorsal view. Elytral apex convex. Elytral punctures confused in mesal half, tend to form rows in lateral half, outermost punctures forming a regular row. Each elytral puncture surrounded by a dark halo, distance between adjacent punctures less than diameter of one puncture, including dark halo.

Maximum width of elytral epipleura subequal to that of midfemur. Epipleura subhorizontal, visible in lateral view, widest at proximal one-fourth, gradually narrowing till distal one-third and then abruptly narrowed, hardly reaching apex. Prosternum gently depressed on top, setose, coarsely but shallowly punctate; minimum distance from anterior margin of prosternum to coxal cavity less than half of minimum width of prosternal intercoxal process; prosternal intercoxal process longer than wide, narrowed in middle, widened apically, posterior margin concave. Mesosternum transverse, nearly three times wider than long, with concave posterior margin; metasternum profusely setose medially, coarsely punctate. First abdominal ventrite profusely setose medially, coarsely punctate; in length, medially subequal to next three combined. Last ventrite a little longer than preceding two combined. Last visible tergite medially with a broad longitudinal groove not reaching apex.

Foretibia without apical spine. Mid- and hind tibiae with apical spine. First pro-, meso-, and metatarsomeres distinctly wider in male than in female; with capitate setae ventrally in male and pointed setae in female. Posterior margin of last ventrite entire in female; forms a lobe notched on either side, in middle in male. Last ventrite internally with a longitudinal apodeme along mid-line in male ( Fig. 12a ), externally visible as a dark line; apodeme absent in female ( Fig. 12b ).

Male genitalia with aedeagus in lateral view ( Fig. 12f ) curved, apex acutely pointed, recurved dorsally. In ventral view ( Fig. 12g ), aedeagus with a longitudinal depression along middle of ventral side, depression being stronger distally; aedeagus narrowed apically forming a triangular denticle. Dorsal opening ( Fig. 12h ) partially covered with three laminae.

Female genitalia with spermathecal receptacle ( Fig. 12e ) oblong, widest in middle, narrowed towards both ends, 2.2 × longer than broad. Vaginal palpi ( Fig. 12c ) medially fused, both together 1.75 × broader than long, posterior margin deeply emarginate with a seta on either side. Tignum ( Fig. 12d ) channeled along middle, posterior membranous area broadened greatly with posterior margin emarginate medially with a few short setae; tignum gently broadened anteriorly.

Nature of damage.

Adults feed on the abaxial surface of the leaf lamina, making transverse, narrow linear scars. Feeding by Basilepta subcostata results in much shorter and broader feeding troughs, which is very different from that of Bhamoina varipes .

Distribution.

India (Assam; Meghalaya; Uttarakhand (Dehra Dun)); Myanmar; Nepal ( Medvedev 2000); Vietnam; China ( Dӧberl 2010); Sumatra; Laos.

Figures

Figure 10. Bhamoina varipes (Jacoby). a, b. Dorsal view; c. Head, dorsal view; d. Pronotum, dorsal view; e. Lateral margin of pronotum.

Figure 11. Type of Sphaeroderma varipennis Jacoby (= B. varipes) (female). a. Dorsal view; b. Pronotum of S. varipennis; c. Anterolateral corners of pronotum (magnified).

Figure 12. Bhamoina varipes (Jacoby). a. Abdominal apex, male; b. Abdominal apex, female; c. Vaginal palpi; d. Tignum; e. Spermatheca; f-h. Male genitalia: f. Aedeagus, lateral view; g. Aedeagus, ventral view; h. Aedeagus, dorsal view.