Taphinellina bengalensis, Jacoby, 1900

Bezděk, Jan, Online, Published & Version, Final, 2016, Redescription and identity of Taphinella bengalensis Jacoby, 1900 (Coleoptera: Chrysomelidae: Galerucinae), Turkish Journal of Zoology 40 (6), pp. 120-124 : 122-124

Taphinellina bengalensis : Maulik, 1936: 299; Wilcox, 1973: 449 (catalogue).

Type locality. “ Mandar, Bengal ” [ India, Rajasthan prov., 24°33ʹ24ʺN 72°23ʹ14ʺE] .

Type material examined. Lectotype: ♂ ( BMNH), “Type / H. T. [round white label with red collar, printed]

// Mandar (Beng.) / P. Cardon 7/91 / Det. 92 [white label, printed] // Jacoby Coll. / 1909-28a. [white label, printed] // Taphinella / bengalensis / Jac. [blue label, handwritten] // LECTOTYPUS, / Taphinella / bengalensis Jacoby, 1900 / des. J. Bezděk, 2014 [red label, printed]”. Paralectotypes: 1 ♂ ( BMNH), “Mandar / Bengal [white label, handwritten] // Jacoby Coll. / 1909-28a. [white label, printed] // PARALECTOTYPUS, / Taphinella / bengalensis Jacoby, 1900 / des. J. Bezděk, 2014 [red label, printed]”; 1 ♂ ( ISNB), “Coll. R. I. Sc. N. B. / Inde [yellow label, printed] // Mandar (Beng.) / P. Cardon 7/91 / Det. 92 [white label, printed] // det. [printed] Jacoby 1900 [white label, handwritten] // Taphinella / bengalensis / Jac. [blue label, handwritten] // Syntype [white label with red letters, printed]”.

One additional paralectotype is deposited in ISNB but not examined. Another paralectotype (♂) is deposited in MCZ - color photos of it are available at: http://mczbase. mcz.harvard.edu/TaxonomySearch.cfm and is provided with the following labels: “Mandar / Bengal [white label, handwritten] // 2nd Jacoby / Coll. [white label, printed] // bengalensis / Jac. [white label, handwritten] // [blank white label] // TYPE [p] / 18247 [red label, handwritten]” .

Additional material examined. INDIA: Rajasthan: 1 ♀, Genji [23°42ʹ30ʺN 73°41ʹ31ʺE], Coromandel leg. ( NMPC) .

Redescription. Measurements. Males: 3.2–3.5 mm (lectotype 3.5 mm), female: 4.6 mm.

Male (lectotype, Figure 7 ). Body lustrous, glabrous dorsally, oval, convex. Coloration: dorsal side dark brown with metallic tint, pronotal anterior apices and frontal tubercles on head pale brown; ventral side brown with slightly paler anterior parts of pronotal hypomera, prosternum, meso- and metasternal processes and basal part of abdominal ventrite I; legs orange, antennae black with antennomeres I–III orange.

Head ( Figures 9, 10 ). Labrum transverse, with several pores in transverse row bearing pale seta, anterior margin slightly emarginate. Anterior part of head distinctly sparsely punctate, glabrous, but with sparse setae on anterior margin of clypeus and along eye margins. Nasal keel triangular, posterior tip separates anterior tips of frontal tubercles. Interantennal space 1.75 times as wide as transverse diameter of antennal socket. Eyes small, interocular space three times as wide as transverse diameter of eye. Interocular space 2.62 times as wide as transverse diameter of eye. Frontal tubercles large, subpentagonal, elevated, lustrous, glabrous, nearly impunctate, anterior tips divergent. Vertex separated from frontal tubercles by shallow distinct furrow, glabrous, covered with sparse fine punctures. Antennae slender, length ratio of antennomeres I–VIII (rest broken) equals 10-7-8-9-9-9-9- 9-9. Antennomeres I–III semiopaque, covered with sparse setae, antennomeres IV–IX dull, covered with dense setae.

Pronotum ( Figures 9, 10 ) 1.55 times as broad as long, strongly convex, without any discal impressions, widest in anterior third, covered with distinct punctation, interspaces ca. 2–3 times larger than the diameter of punctures. Anterior margin moderately concave, lateral margins widely rounded, posterior margin moderately rounded. Anterior margin thinly bordered, lateral margins widely bordered, channeled, posterior margin thinly bordered, border slightly wider towards posterior margin. Anterior angles swollen, directed anteriorly, posterior angles tooth-like, all angles with setigerous pore bearing long pale seta. Posterior margin of pronotum with two short notches, placed ca. at 1/5 of pronotal width from posterior angles. Scutellum subtriangular, impunctate, glabrous, with widely rounded apex.

Elytra 1.21 times as long as wide and 0.71 times as long as body, glabrous, widest in the middle, lateral margin widely rounded, disc densely covered with two kinds of punctures: larger punctures that tend to form regular rows (visible mainly in anterior third of elytra) mixed with sparse very fine confused punctures. Humeral calli well developed, almost impunctate. Epipleura impunctate, very wide in basal third, gradually narrowing in apical two thirds towards to apex. Macropterous.

Legs moderately slender. All tibiae without apical spur. Protarsomere I elongate triangular, as wide as protarsomere II, protarsomere II triangular, length ratio of protarsomeres I–IV: 7-5-5-7, of metatarsomeres I–IV: 9-5- 5-8. Claws appendiculate.

Ventral surface ( Figure 8 ) lustrous, sparsely covered with punctures and long pale setae. Anterior coxal cavities closed posteriorly. Prosternal process wide, slightly impressed, well visible between procoxae ( Figure 11 ). Abdomen simple, last ventrite transverse, posterior margin with two short triangular incisions, space between incisions straight and relatively wide ( Figure 4 ). Pygidium with well-developed median furrow.

Aedeagus symmetrical, parallel, apex gradually convergent with rounded apex. In lateral view moderately bent and gradually narrowing to sharp apex ( Figure 1 ). Without visible internal sclerites.

Female ( Figure 13 ). Labrum quadrate with six pores in somewhat bent row. Interantennal space 1.45 times as wide as transverse diameter of antennal socket. Interocular space wider, 3.05 times as wide as transverse diameter of eye. Pronotum 1.62 times as broad as long. Last abdominal ventrite subtriangular with apex distinctly emarginated ( Figure 5 ). Elytra longer than in males, 1.41 times as long as wide and 0.72 times as long as body. Protarsi narrower than in males. Spermatheca: cornu shortly C-shaped, gradually narrowing to apex, base inserted into sphaerical nodulus, proximal spermathecal duct connected to nodulus in axis ca 90°, slightly wider basally ( Figure 6 ). Vaginal palpi divided in apical 2/5, in middle slightly extended, 6 setae placed along outer margin of each apical process ( Figure 3 ). Sternite VIII elongate oval, setae cumulated on anterior third of surface and on anterior margin, tignum slender, short, as long as sternite VIII ( Figure 2 ).

Distribution. India (Rajasthan).

Differential diagnosis. Most of Cassena species have typical coloration of dorsum with head and pronotum red and elytra metallic blue. However, about one quarter of species have different coloration, often not metallic. Uniformly pale dorsum occurs only in three Cassena species: C. costalis Medvedev, 2009 from Thailand (differs from C. bengalensis by elytra costate laterally), C. sasajii Kimoto, 1969 from Taiwan (dorsum yellow with head darker), and C. uniformis (Bryant, 1954) from Myanmar (dorsum completely yellow). Similar brown coloration of dorsum can also be found in C. oculata Laboissière, 1934 from Vietnam but this species has a large yellow subapical spot on each elytron.

Figures

Figures 7–13. Cassena bengalensis (Jacoby, 1900). 7–12. lectotype of Taphinella bengalensis (male, 3.6 mm): 7 – dorsal view, 8 – ventral view, 9 – head and pronotum in frontal view, 10 – head and pronotum in dorsal, 11 – head and prosternum in ventral view, 12 – labels of lectotype. 13 – female (4.6 mm).

Figures 1–6. Cassena bengalensis (Jacoby, 1900): 1 – aedeagus in dorsal (left) and lateral (right) views, 2 – tignum and sternite VIII, 3 – vaginal palpi, 4 – male last ventrite, 5 female last ventrite, 6 – spermatheca in dorsal and lateral views. Scales: 0.5 mm for Figures 1, 4, and 5; 0.25 mm for Figures 2, 3, and 6.