Atholus singalanus ( Marseul, 1880 )

Cruz, Ian Niel dela, Hartini, Sri, Dwibadra, Dhian & Ôhara, Masahiro, 2024, Contribution to the Knowledge of the Genus Atholus (Coleoptera: Histeridae: Histerinae: Histerini) from the Indonesian Archipelago, Species Diversity 29 (1), pp. 119-139 : 131-135

publication ID	https://doi.org/ 10.12782/specdiv.29.119
persistent identifier	https://treatment.plazi.org/id/607587A7-FF9D-4819-FC21-33D8D00BFDFF
treatment provided by	Felipe
scientific name	Atholus singalanus ( Marseul, 1880 )
status

Treatment

Atholus singalanus ( Marseul, 1880) View in CoL

( Figs 1F View Fig , 9A–F View Fig , 10A–H View Fig , 12 View Fig )

Hister singalanus Marseul, 1880: 157 View in CoL (type locality: Sumatra).

Atholus singalanus View in CoL : Lewis 1906: 402 (listed); Mazur 1984: 217; Mazur 1997: 133; Mazur 2011: 106 (catalogued).

Hister (Atholus) singalanus View in CoL : Bickhardt 1910: 55; Bickhardt 1917: 194 (catalogued); Desbordes 1917: 322 (keyed).

Specimen examined. One specimen of undetermined sex. Sumatra Island: West Sumatra, Sukarami , Bukit Gompong, NE 20 km from Padang, 19 August 1998 [No. 9856], M . Ôhara leg . [IC-22-in07] (1 ex. SEHU) .

Diagnosis. Atholus singalanus is generally identified for its combined character of uninterrupted lateral stria of pronotum, and very short external subhumeral stria located on the basal end.

Re-description. Body length: PEL: 3.40 mm; APW:

1.35 mm; PPW: 2.60 mm; EL: 1.85 mm; EW: 3.00 mm. Body ( Figs 1F View Fig , 9A–C View Fig ) oval, convex and black; tibia, antenna, mouthparts and elytral apical margin rufous.

Head. Forehead divided into two by rather weak median longitudinal impressions; anterior margin of clypeus entire and slightly produced, anterolateral margin sinuous; frontal stria ( Fig. 9D View Fig ) round, complete and deeply impressed; disk with alutaceous ground sculpture and clothed with very sparse, fine punctures; occipital fovea absent; eyes large and convex, well-visible dorsally; labrum punctate, raised and transversely wide, absent labral fringe; mandible covered with fine punctations, acutely pointed at apex, outer margin rounded and curved inwardly.

Pronotum. Marginal pronotal stria laterally complete and broadly interrupted behind head; lateral pronotal stria ( Fig. 9E View Fig ) deeply impressed and complete, almost reaching the posterior margin of pronotum, lateral stria rather distant from the lateral margin; anterior pronotal stria present, connected with lateral stria; disk with sparse microscopic punctures, clothed with alutaceous microsculpture; area behind apical angle bare; posterior margin rather bare; ante-scutellar region with short, single longitudinal puncture.

Elytra. Anterior margin with short, longitudinal striae on apical area around antero-scutellum; epipleural fossette smooth and impunctate; epipleural marginal stria present on apical half; elytral marginal stria complete and moderately impressed; external subhumeral stria ( Fig. 10B View Fig ) moderately impressed, present medio-basally and for about 1/3 of the elytral length; internal subhumeral stria absent; oblique stria slightly impressed on basal third; dorsal striae ( Fig. 10A View Fig ) 1–3 complete, dorsal 4 present on apical half, sometimes joined to dorsal stria 5 on apical end, dorsal stria 5 present on apical third; sutural stria shorter, present on apical fourth; discal surface similar to pronotum with alutaceous microsculpture.

Propygidium and pygidium. Propygidium ( Fig. 10E, F View Fig ) densely covered with coarse and round punctures, separat- ed by their own to twice their diameter, the puncture about 30 µm in diameter; interspace among the coarse punctures moderately covered with fine punctations; pygidium with punctations ( Fig. 10E View Fig ) similar to those of propygidium, but finer and becoming sparser on the apex, separated by their own diameter; interspace among the coarse punctures covered with fine punctations.

Prosternum. Prosternal lobe with round anterior margin ( Fig. 10C View Fig ), medio-apical end ascending; marginal stria deeply impressed, carinated and entire, brief striae present on basolateral ends; lobe with coarse punctures on basolateral sides, the punctures separated by their own diameter, interspace among the punctures covered with sparse and fine punctations, prosternal suture inconspicuous; prosternal process covered with sparse, fine punctures, lateral sides descending; descending lateral stria deeply impressed and carinate; lateral disk with coarse punctations; basal half of process slightly narrow, posterior margin of basal lobe emarginated.

Meso- and metaventrite. Anterior margin arcuate outwards ( Fig. 10D View Fig ), marginal stria complete and moderately impressed, stria behind anterolateral angle present; disk sparsely clothed with fine punctures, which are separated by three to five times of their diameter; meso-metaventral suture moderately impressed, complete and carinated; metaventral lateral stria ( Fig. 10D View Fig ) deeply impressed, extending obliquely and posteriorly, united with oblique stria which extends inwardly from basal fifth of metaventro-metepisternal suture, oblique stria moderately crenated; post-mesocoxal stria extending posteriorly and strongly curved along the posterior margin of mesocoxa, attaining the metaventro-mesepimeral suture; metaventrite with punctations of intercoxal disk similar to those of mesoventral plate; row of coarse punctures sometimes present along inside of basal portion of lateral stria; longitudinal suture slightly impressed; lateral disk moderately descending medially, densely covered with setiferous, large, round and shallow punctures; interspaces among these punctures with sparse, fine to coarse punctations; mesepimeron and metepimeron covered with densely setiferous, large punctures; interspaces among the punctures with few, fine to coarse punctations; metepisternum with sparse punctures on apical half; first abdominal sternite with punctation of intercoxal disk similar to that of metaventrite; surface of lateral disk similar to mesepimeron and metepimeron; lateral stria of intercoxal disk deeply impressed, slightly carinate and complete.

Legs. Protibia ( Fig. 10G View Fig ) flattened on the anterior portion, slightly dilated and clothed with a few, fine ocelloid punctures; median area with weak strigate sculpture; outer lateral margin with two or three unremarkable teeth topped by short denticles; outer apical tooth weak and rounded; anterior stria moderately impressed, shortened on basal end; inner marginal stria bearing on basal half, inner apical margin with few sclerotized setae; posterior surface ( Fig. 10H View Fig ) covered with sparse, fine punctures, strigate ground sculpture on outer surface; outer region slightly descending; number of denticles in both outer lateral margin and apical margin combined 10, one on inner apical angle, outer sublateral margin 5; protibial spur moderately long, almost half the length of protarsus, extending from apical margin of protibia; median posterior stria complete and moderately impressed; inner posterior stria moderately impressed on basal half, with row of sclerotized setae; row of setae on inner margin of protibia with strigate ground sculpture; protarsal groove shallow; protarsus with two spine-like tarsal denticles near tarsal insertions, another one larger and more distant, located near inner anterior angle; profemur clothed with fine punctations, very few, coarse punctures on median area, surface with slightly strigate ground sculpture; marginal stria complete, anterior stria present on apical half; femoral stria almost complete, abbreviated on basal end; posterior margin with large punctations, row of setae present on both basal and apical terminals.

Male genitalia. Not available.

Female genitalia. Not available.

Distribution. Indonesia: endemic to Sumatra Island ( Fig. 12 View Fig ).

Remark. Atholus singalanus has been collected in a decaying debris of bamboo.

Kingdom	Animalia
Phylum	Arthropoda
Class	Insecta
Order	Coleoptera
Family	Histeridae
Genus	Atholus