Pachylister ceylanus pygidialis (Lewis) (Fig. 4, 5)
Pachylister pygidialis Lewis, 1906, 399.
Hister pygidialis: Jakobson, 1911, 643.
Pachylister ceylanus: Kryzhanovskij and Reichardt, 1976, 302 [Korean peninsula: Seoul].
Pactolinus ceylanus pygidialis: Mazur, 1984, 180; ESK & KSAE, 1994, 137 [Korea].
Frontal stria of head (Fig. 4A) distinctly impressed and finely crenated, the middle of anterior portion slightly interrupted. Head regularly and finely punctate, the punctures separated by 3 - 5 times their diameter. Mandibles well developed. Anterior margin of labrum weakly angulated outwardly.
Pronotal sides (Fig. 4B) regularly arcuate and convergent apically. Apical angle obtusely angulate. Marginal pronotal stria complete laterally and broadly interrupted behind head. Outer lateral pronotal stria impressed on apical half. Inner lateral stria deeply impressed, carinated, abbreviated on basal one-eighth, interrupted slightly behind apical angles, and broadly interrupted behind head. Disk of pronotum sparsely covered with fine punctures that are separated by 4 - 5 times their diameter; interstices among punctures clothed with alutaceous sculptures; a row consisting of coarse punctures present along posterior margin. Posterior margin of pronotum strongly sinuate and obtusely angulated posteriorly at middle.
Epipleural marginal stria complete and distinctly carinate ventrally; elytral marginal stria absent; disk of epipleural deeply excavated on posterior half and coarsely punctate. External subhumeral stria (Fig. 4B) present on posterior half. Oblique humeral stria lightly impressed on basal half. First to third dorsal striae deeply impressed and complete; fourth dorsal stria present on apical half; fifth rudimentary stria represented by few punctures on apical area. Surface of elytra clothed with alutaceous sculptures and finely punctate along suture; a narrow band along posterior margin clothed with strigose microsculpture.
Propygidium irregularly covered with fine and moderate sized punctures, the punctures separated by 1 - 5 times their diameter; disk wholly clothed with strigose ground microsculpture. Pygidium sparsely and coarsely punctate, the punctures separated by 1 - 4 times their diameter and become denser apically; interstices among the coarse punctures irregularly and finely punctate; disk clothed with strigose ground microsculpture; posterior margin elevated; ventral area shiny and only clothed with fine punctures.
Anterior margin of prosternal lobe (Fig. 4C) round, the anterior portion nearly straight; marginal stria clearly and completely impressed and carinate; disk evenly covered with coarse punctures that are separated by 2 - 3 times their diameter and become sparser on middle. Prosternal keel narrow and without carinal stria; disk densely covered with coarse and large punctures on lateral area, and sparsely and moderately punctate on top of keel. Lateral stria deeply impressed and carinate.
Anterior margin of mesosternum (Fig. 4C) strongly emarginate at middle; marginal stria well impressed, carinate and interrupted medially; another short stria present behind each anterior angle; disk covered with alutaceous sculptures. Meso-metasternal suture lightly impressed, indistinct medially. Post-mesocoxal stria of metasternum extending along posterior margin of mesocoxa, and becoming distant from the margin, the outer end attaining at middle of metasternal-mesepimeral suture. Lateral metasternal stria clearly impressed and carinate, obliquely extended posteriorly, and united with oblique stria, that is carinate and inwardly extends from the middle of metasternal-metepisternal suture. Punctation of intercoxal disk similar to that of mesosternum. Anterolateral disk densely covered with shallow, large and setiferous punctures, the punctures becoming finer and sparser inwardly. Posterolateral disk densely and coarsely punctate.
Intercoxal disk of first abdominal sternum with similar punctation to that of the intercoxal disk of mesosternum; lateral stria deeply impressed and complete.
Protibia (Fig. 4D, E) with 3 large denticles on outer margin, the apical most denticle with 2 spines. Meso- and metatibiae with 2 rows, each consisting of 10 - 13 stout spines. Profemoral stria complete and strongly carinate.
Male genitalia as shown in Fig. 5. Aedeagus of male genitalia slender; basal piece small; ratio of parameres length to basal piece about 5.5.
Material examined. Jeonranam-do: Is. Naro-do, 10/vi/1995 (1 ex., J.-C. Paik).
Remarks. Pachylister ceylanus pygidialis may superficially resemble
Hister congener and H. japonicus in general habits, but can be distinguished
by the generic characters in the key.