Tetraserica takakuwai, Ahrens, 2022

Tetraserica takakuwai View in CoL sp. nov.

( Fig. 1 A-D)

ZooBank:http://zoobank.org/ 8EAA0977-F5A1-4F1B-8207-68926110E12F

Holotype, ♂, “Phu Rua NP ( 900m alt.), Loei O. NE Thai. 26-30IV. 2006 Takakuwa, M. leg./ 1154 Sericini Asia spec.” ( ZFMK).

Description of the holotype.

General appearance.

– Length of body: 7.4 mm;

– Length of elytra: 5.4 mm;

– Maximum width: 4.4 mm.

Dorsal surface reddish brown; surface of labroclypeus and disc of frons glabrous.

Head. – Labroclypeus subtrapezoidal, wider than long, widest at base, lateral margins moderately convex and convergent to strongly rounded anterior angles, anterior margin weakly sinuate medially, margins moderately reflexed. – Surface weakly convex, moderately shiny, finely and densely punctate. – Frontoclypeal suture indistinctly incised, flat and weakly curved medially. – Ocular canthus short and triangular, impunctate, with a single terminal seta. Smooth area anterior to eye twice as wide as long. – Frons dull,

Reviewers:

Denis Keith ( France) - ZooBank: http://zoobank.org/ C922B63D-331E-44BF-B386-9A70AE05CA28

with sparse, fine punctures, with single erect setae beside each eye. – Antenna yellowish, with ten antennomeres; club composed of four antennomeres in male, straight, rarely longer than 1.5 times as the remaining antennomeres combined. – Eyes moderatelysmall,ratio of diameter/interocular width:0.71. – Mentum elevated and slightly flattened anteriorly.

Thorax. – Pronotum moderately wideandstronglyconvex,lateralmargins evenly convex, more strongly narrowed anteriorly towards sharp and slightly produced anterior angles. – Anterior margin of pronotum slightly convex, with fine complete marginal line. – Posterior angles blunt or strongly rounded. – Surface finely and densely punctate, except minute setae glabrous, lateral and lateral anterior margins sparsely setose. – Hypomeron not carinate. – Scutellum triangular, finely and densely punctate.

Elytra. – Oblong, widest just behind middle, striae distinctly impressed, finely and moderately densely punctate, intervals distinctly convex, with coarse and dense punctures concentrated along striae, with very minute setae in punctures. – Epipleural edge robust, ending at weakly curved and slightly blunt external apical angle of elytra, epipleura densely setose, apical border with a broad fringe of microtrichomes (100x).

Ventral. – Surface weakly shiny, finely and densely punctate, metasternum sparsely covered with fine, short, or very minute setae, metacoxa glabrous, with a few single setae laterally. – Abdominal sternites finely and densely punctuate, with a transverse row of coarse punctures, each bearing a robust seta. – Mesosternum between mesocoxae as wide as mesofemur.Ratio of length of metepisternum/metacoxa: 1/1.67. – Pygidium weakly convex and dull, densely punctate, without smooth midline, almost glabrous, but with a few longer setae along apical margin; pygidium without strong sexual dimorphism.

Legs. – Moderately wide. – Femora finely and sparsely punctate. – Metafemur wide and moderately shiny or dull, anterior margin acute, posterior margin smooth ventrally and only weakly widened in apical half, posterior margin smooth dorsally, with a few short setae basally. Posterior margin of metafemur generally straight or slightly convex. – Metatibia short and wide, ratiowidth/length:1/2.8; basal group of dorsal spines of metatibia at first third of metatibial length. Robust spine at middle of ventral margin extremely prolonged and s-shaped, exceeding distal margin of metatibia. – Tarsomeres with fine, very dense setae ventrally on distal half, neither laterally nor dorsally carinate, dorsally smooth. – Metatarsomeres with a strongly serrated ridge ventrally and glabrous;first metatarsomere slightly shorter than two following tarsomeres combined, one third of its length longer than dorsal tibial spine. – Protibia short, bidentate; anterior claws symmetrical, basal tooth of both claws bluntly truncate at apex.

Male genitalia. – Aedeagus: Fig. 1A–C.

Remarks. – Female unknown.

Diagnosis. – Tetraserica takakuwai sp. nov. is in shape of aedeagus most similar with Tetraserica bansanpakiana Fabrizi, Dalstein & Ahrens, 2019 and T. margheritae Fabrizi, Dalstein & Ahrens, 2019 ( Fig. 2).

It shares with both species:

- the robust metatibial spine in middle of ventral margin being extremely elongate and s-shaped, exceeding distal margin of metatibia,

- short median lamina of phallobase,being subequal to at maximum half of length of phallobase,

- the unicolored dorsal surface,

- the left paramere being at base simple,and the strongly asymmetric phallobase (dorsal view).

Tetrasericatakakuwai sp. nov. differs from T. bansanpakiana by:

- the longer and narrower median lamina of phallobase which does not possess an apical dorsal tooth ( Fig. 2A, C),

- the basal uncleft portion of the left paramere is much longer ( Fig. 1A), although if the apical branches appear to be broken in the holotype of T. takakuwai sp. nov.

From T. margheritae the new species differs by:

- the dorsoventrally wider median lamina of phallobase whose dorsal margin is weakly convex and not straight as in T. margheritae ( Fig. 2E);

- the left paramere is basally not bent as in T. margheritae ( Fig. 2E; lateral view) but straight in basal third ( Fig. 1A), and over its length (lateral view) weakly curved instead of straight as in T. margheritae;

- in dorsal view, the left paramere is in T. takakuwai sp. nov. straight and not curved externally ( Fig. 1B) as in T. margheritae ( Fig. 2F).

Etymology. – The new species is named after its collector, M. Takakuwa (nouningenitivesingular).