Charidotis amazona, Sekerka, 2016

Sekerka, Lukáš, 2016, Taxonomic and nomenclatural changes in Cassidinae (Coleoptera: Chrysomelidae), Acta Entomologica Musei Nationalis Pragae 56 (1), pp. 275-344 : 286-289

Charidotis amazona sp. nov.

Charidotis orbifera [misidentifications]: WEISE (1921): 202 (description, faunistics); SPAETH (1936): 86 (key); BOROWIEC (2009c): 646 (faunistics); BOROWIEC & TAKIZAWA (2011): 435 (faunistics).

Type locality. Brazil, Amazonas, Rio Autáz.

Type material. HOLOTYPE: pinned, ‘Rio | Autaz [w, p, cb] || Amazon | Roman [w, p, cb] || nov. [w, p, cb] || NHRS- JLKB | 000022809 [w, p, cb]’ ( NHRS). PARATYPES: 1 spec., pinned, ‘Maná- | os [w, p, cb] || Amazon | Roman [w, p, cb] || mars [w, p, cb] || NHRS-JLKB [w, p, cb] || 000022810 [w, p, cb]’ ( NMPC) ; 1 spec., glued, ‘ Brazil Amazonas | Tapurucuara | Rio Negro | 27.xi.1962 [w, p, cb]’ ( LSPC).

Description. Measurements (n = 2): length of body: 5.61–6.30 mm, width of body: 4.65–5.49 mm, length of pronotum: 1.74–1.78 mm, width of pronotum: 3.54–3.89 mm, length/width of body ratio: 1.14–1.20, width/length of pronotum ratio: 1.98–2.24. Body broadly rounded, subcircular in outline.

Dorsum yellow with a wide black ring covering basal half of disc of pronotum, scutellum, basal and apical 1/5 of disc of elytra, and laterally extends from the fourth to the ultimate row of punctures. Ventral side uniformly yellow, only antennomere X infuscate and XI black.

Pronotum semicircular without sharp corners, with maximum width slightly behind midlength, and lateral sides broadly rounded. Anterior margin regularly rounded and slightly projecting forwards. Disc moderately convex, smooth and shiny, with several micropunctures on the top and groups of moderately coarse punctures on slope on each side. Explanate margin indistinctly separated from disc, slightly declivous, broad, smooth and shiny, impunctate, structured like a honeycomb.

Scutellum triangular, smooth, shiny, and micro-reticulate.

Base of elytra slightly wider than base of pronotum. Basal margin moderately curved towards humeral angles, simple and smooth. Humeral angles moderately protruding anteriorly and obtuse. Disc regularly convex, smooth and shiny, principal impression weak. Punctation regular, punctures moderately coarse and gradually increasing from top of disc towards lateral margin. Scutellar row absent. Punctures mostly tightly arranged in rows separated by less than half of their diameter, with several wider interspaces on top of elytra. Intervals wide, 2–3× as wide as puncture diameter. Submarginal row distinct, normal. Marginal row distinct in whole length and with distinct vacancy around midlength, its punctures slightly coarser than punctures on slope of disc. Explanate margin moderately broad, moderately declivous, strongly narrowed in apical part, smooth and shiny, impunctate, and structured like a honeycomb. Apex of elytral epipleura sparsely pubescent.

Eyes large, occupying laterally almost enitre head, genae short. Clypeal lines sparsely pubescent, fine, running along eyes to antennal insertions and converging in obtuse arch. Clypeus nearly as wide as long, flat, smooth and shiny, impunctate, and microreticulate. Labrum moderately broad, lower margin regularly inflexed without emargination and with faint carina. Antennae moderately long, with five basal glabrous antennomeres and six distal ones moderately increased. Ratio of antennomere lengths: 100: 60: 38: 48: 45: 80: 74: 71: 69: 69: 143. Antennomere II 1.6× as long as III; IV and V approx. 1.7× as long as VI, IX and X subequal in length.

Prosternal collar typical for genus, slightly impressed on its sides. Prosternal process broad, slightly constricted in the middle, moderately expanding apically, its surface shiny, irregular, and micro-rugose.

Legs unmodified. Claws divergent, simple. Fore claws without distinct micropecten, mid and hind with short but easily visible micropecten.

Differential diagnosis. Charidotis amazona sp. nov. belongs to the group of species characterized by a smooth and not shortened clypeal plate, elytra mostly regularly punctate with broad intervals and uniformly yellow explanate margin, dorsum with a black ring, and antennomeres IV and V distinctly shorter than VI. The group comprises five species and the new species runs to the thesis 195 of SPAETHʼs (1936) key and replaces C. orbifera Boheman, 1855 which is here synonymized with C. nucleata Boheman, 1855 (see more details under the latter species).

Charidotis amazona sp. nov. stands nearest to C. nucleata Boheman, 1855 and C. cognata Boheman, 1855 as all three possess a shallow but distinct principal impression on the elytra, resulting in the internal four rows of punctures on each elytron being interrupted by a faint callosity. Moreover, the elytra are unevenly convex in lateral view with a distinct callosity in the postscutellar area. The remaining species of the group, C. ambigua Boheman, 1855 , C. arrowi Spaeth, 1936 and C. turialbana Spaeth, 1936 , do not have a distinct principal impression; the internal four rows are thus nearly regular in the postscutellar area and the elytra are regularly convex without any callosity. Charidotis cognata and C. nucleata differ by the denser and coarser punctation of elytra with narrower intervals and narrower clypeus. Charidotis amazona sp. nov. has the lowest postscutellar callosity, stoutest body and finest punctation of the three similar species.

Etymology. The species epithet is an adjective and reffers to its terra typica, the State of Amazonas, Brazil.

Remarks. WEISE (1921) published two specimens from Rio Autáz and Manaus (Amazonas, Brazil) as C. orbifera . He assumed that Boheman did not possess fully coloured specimen(s) for the description of the latter species and thus provided an additional description. This assumption was probably based entirely on the primary description, as Weise pointed the ferruginous colouration of the scutellum (mentioned in the original description) while in both specimens he examined it was black. However, the holotype of C. orbifera is a fully sclerotized and coloured specimen and is also characterized by a ring becoming somewhat ferrugineous towards the center of the elytra.

SPAETH (1936) placed C. orbifera next to C. nucleata in a group characterized by antennomeres IV and V being distinctly shorter than VI and distinguished them from others by the impunctate callosity interrupting the inner rows of punctures in the postscutellar area. Furthermore, he followed characters mentioned by WEISE (1921) to separate C. nucleata and C. orbifera that include colouration, punctation and convexity of the elytra. I have examined both specimens published by Weise and found that they are very different from C. orbifera and thus are here described as Charidotis amazona sp. nov.

Distribution. Brazil: Amazonas ( WEISE 1921, BOROWIEC 2009c, BOROWIEC & TAKIZAWA 2011).