Trichotichnus (Bottchrus) nanus Habu, 1954

Kim, Dooyoung & Suh, Sang Jae, 2022, Taxonomic and faunistic notes on the genus Trichotichnus from Korea (Coleoptera, Carabidae, Harpalinae, Harpalini), Biodiversity Data Journal 10, pp. 83804-83804 : 83804

Trichotichnus (Bottchrus) nanus Habu, 1954

Trichotichnus nanus Habu, 1954 - Habu 1954c: 255.

Trichotichnus (Trichotichnus) nanus : Habu, 1961 - Habu 1961: 144.

Trichotichnus (Pseudotrichotichnus) nanus : Habu, 1973 - Habu 1973: 226.

Trichotichnus (Bottchrus) nanus : Kataev and Wrase, 2017 - Kataev and Wrase 2017: 558.

Materials

Type status: Other material. Occurrence: sex: 5 males, 4 females; lifeStage: adult; Taxon: scientificName: Trichotichnus (Bottchrus) nanus; order: Coleoptera; family: Carabidae; genus: Trichotichnus; subgenus: Bottchrus; specificEpithet: nanus; vernacularName: 꼬마윤머리먼지벌레; Location: country: Korea; stateProvince: Daegu-si; locality: Suseong-gu, Beommul-dong, Jinbatgol, Coll. Dooyoung Kim ; verbatimLatitude: 35°48'36.1"N; verbatimLongitude: 128°39'44.5"E; Event: samplingProtocol: under the leaf litter; eventDate: 1.VII.2021; Record Level: basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: sex: 3 males; lifeStage: adult; Taxon: scientificName: Trichotichnus (Bottchrus) nanus; order: Coleoptera; family: Carabidae; genus: Trichotichnus; subgenus: Bottchrus; specificEpithet: nanus; vernacularName: 꼬마윤머리먼지벌레; Location: country: Korea; stateProvince: Daegu-si; locality: Suseong-gu, Beommul-dong, Jinbatgol, Coll. Dooyoung Kim ; verbatimLatitude: 35°48'36.1"N; verbatimLongitude: 128°39'44.5"E; Event: samplingProtocol: under the leaf litter; eventDate: 10.VII.2021; Record Level: basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: sex: 1 male; lifeStage: adult; Taxon: scientificName: Trichotichnus (Bottchrus) nanus; order: Coleoptera; family: Carabidae; genus: Trichotichnus; subgenus: Bottchrus; specificEpithet: nanus; vernacularName: 꼬마윤머리먼지벌레; Location: country: Korea; stateProvince: Daegu-si; locality: Suseong-gu, Hwanggeum-dong, Duribong, Coll. Dooyoung Kim ; verbatimLatitude: 35°50'17.3"N; verbatimLongitude: 128°38'31.2"E; Event: samplingProtocol: under the leaf litter; eventDate: 26.V.2018; Record Level: basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: sex: 1 male, 1 female; lifeStage: adult; Taxon: scientificName: Trichotichnus (Bottchrus) nanus; order: Coleoptera; family: Carabidae; genus: Trichotichnus; subgenus: Bottchrus; specificEpithet: nanus; vernacularName: 꼬마윤머리먼지벌레; Location: country: Korea; stateProvince: Daegu-si; locality: Suseong-gu, Hwanggeum-dong, Duribong, Coll. Dooyoung Kim ; verbatimLatitude: 35°50'17.3"N; verbatimLongitude: 128°38'31.2"E; Event: samplingProtocol: under the leaf litter; eventDate: 31.V.2018; Record Level: basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: sex: 1 female; lifeStage: adult; Taxon: scientificName: Trichotichnus (Bottchrus) nanus; order: Coleoptera; family: Carabidae; genus: Trichotichnus; subgenus: Bottchrus; specificEpithet: nanus; vernacularName: 꼬마윤머리먼지벌레; Location: country: Korea; stateProvince: Daegu-si; locality: Suseong-gu, Hwanggeum-dong, Duribong, Coll. Dooyoung Kim ; verbatimLatitude: 35°50'17.3"N; verbatimLongitude: 128°38'31.2"E; Event: samplingProtocol: under the leaf litter; eventDate: 6.VI.2018; Record Level: basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: sex: 3 females; lifeStage: adult; Taxon: scientificName: Trichotichnus (Bottchrus) nanus; order: Coleoptera; family: Carabidae; genus: Trichotichnus; subgenus: Bottchrus; specificEpithet: nanus; vernacularName: 꼬마윤머리먼지벌레; Location: country: Korea; stateProvince: Daegu-si; locality: Suseong-gu, Hwanggeum-dong, Duribong, Coll. Dooyoung Kim ; verbatimLatitude: 35°50'17.3"N; verbatimLongitude: 128°38'31.2"E; Event: samplingProtocol: under the leaf litter; eventDate: 15.V.2019; Record Level: basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: sex: 1 male; lifeStage: adult; Taxon: scientificName: Trichotichnus (Bottchrus) nanus; order: Coleoptera; family: Carabidae; genus: Trichotichnus; subgenus: Bottchrus; specificEpithet: nanus; vernacularName: 꼬마윤머리먼지벌레; Location: country: Korea; stateProvince: Daegu-si; locality: Suseong-gu, Hwanggeum-dong, Duribong, Coll. Dooyoung Kim ; verbatimLatitude: 35°50'17.3"N; verbatimLongitude: 128°38'31.2"E; Event: samplingProtocol: under the leaf litter; eventDate: 3.V.2021; Record Level: basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: sex: 1 male; lifeStage: adult; Taxon: scientificName: Trichotichnus (Bottchrus) nanus; order: Coleoptera; family: Carabidae; genus: Trichotichnus; subgenus: Bottchrus; specificEpithet: nanus; vernacularName: 꼬마윤머리먼지벌레; Location: country: Korea; stateProvince: Daegu-si; locality: Suseong-gu, Hwanggeum-dong, Duribong, Coll. Dooyoung Kim ; verbatimLatitude: 35°50'17.3"N; verbatimLongitude: 128°38'31.2"E; Event: samplingProtocol: under the leaf litter; eventDate: 22.VI.2021; Record Level: basisOfRecord: PreservedSpecimen Type status: Other material. Occurrence: sex: 1 male; lifeStage: adult; Taxon: scientificName: Trichotichnus (Bottchrus) nanus; order: Coleoptera; family: Carabidae; genus: Trichotichnus; subgenus: Bottchrus; specificEpithet: nanus; vernacularName: 꼬마윤머리먼지벌레; Location: country: Korea; stateProvince: Daegu-si; locality: Suseong-gu, Hwanggeum-dong, Duribong, Coll. Dooyoung Kim ; verbatimLatitude: 35°50'17.3"N; verbatimLongitude: 128°38'31.2"E; Event: samplingProtocol: under the leaf litter; eventDate: 30.VI.2021; Record Level: basisOfRecord: PreservedSpecimen

Description

Body length: 6.0-7.1 mm, width: 2.6-2.8 mm.

Coloration (Fig. 1 A, B) shiny, reddish black or brownish black, elytra slightly iridescent; antennae, maxillary palpi, labial palpi, lateral margin of pronotum, and legs yellowish brown; labrum and mandibles brownish black or reddish black; apex of each mandible black; ventral side overall reddish brown.

Head (Fig. 1 C, D) convex and glabrous; eye prominent, distinctly convex; tempora flat, about one-third as long as eye; mandible narrowly rounded at apex, not truncate; anterior margin of labrum distinctly, sometimes slightly concave; anterior margin of clypeus slightly emarginate; frontal impression deep throughout, clearly reaching margin of eye and further extending posteriorly to the level of hind margin of eye; supraorbital seta located slightly behind the level of hind margin of eye; microsculpture invisible on disc, consisting of faint isodiametric meshes between supraorbital seta and hind margin of eye; postgena finely ciliate; mentum and submentum separated by transverse suture medially and fused laterally; mentum with distinct tooth, which is narrowly rounded at apex, epilobe gently widened anteriorly, slightly or sometimes distinctly projected beyond lateral lobe; submentum with a long seta and a short seta on each side; ligula narrow, apex truncate, with two apical setae; paraglossa moderately wide, rounded at apex, separated from ligula by somewhat narrow notch; penultimate maxillary palpomere about half as long as apical palpomere; penultimate labial palpomere slightly shorter than apical palpomere; antenna short, extending slightly behind basal margin of pronotum.

Pronotum (Fig. 1 C) convex anteriorly, somewhat flat posteriorly, wider than long, widest near 2/5 from apex, PbW longer than PL; apical margin slightly emarginate, completely bordered; apical angle rounded, very slightly protruding anteriorly; lateral margin with very weak sinuation or without sinuation before basal angle; lateral seta located before widest point, about 1/4 from apex; basal margin almost straight, faintly bisinuate, distinctly longer than apical margin, completely bordered; basal angle obtuse, almost angulate, rounded at tip, not protruding laterally; disc glabrous; median line shallow or deep, interrupted near base, not reaching apical and basal border; anterior impression faint; basal fovea shallow to moderately deep, straight or weakly curved, slightly tilted outwards; basal area punctate through lateral to median area, usually densely punctate in basal fovea and sparsely punctate in lateral area; lateral area sparsely punctate from base to mid-point; apical area and disc almost smooth; microsculpture invisible on disc. PW/HW = 1.37-1.44, mean 1.40; PW/PL = 1.28-1.38, mean 1.33; PW/PbW = 1.15-1.25, mean 1.19, in ten males and ten females.

Elytra convex, widest before middle; basal edge evenly curved, forming an obtuse angle with lateral margin; humerus with indistinct blunted tooth visible from behind; apical sinuation very weak; intervals somewhat flat, slightly convex near lateral area and apex, without punctation; setigerous pore of interval 3 located between 1/2 to 3/5 from base; striae moderately deep; parascutellar striole not long, sometimes quite short; marginal umbilicate series with 7-10 pores (usually 8 pores) in anterior group and 9-12 pores (usually 10 pores) in posterior group; microsculpture invisible on disc. Hind wing fully developed. EW/PW = 1.27-1.35, mean 1.31; EL/EW = 1.48-1.55, mean 1.52, in 10 males and 10 females.

Ventral side (Fig. 1 B, E) convex; prosternum covered with very short and fine pubescence; median area of metasternum and median area of abdominal sternites III-VII more sparsely pubescence than prosternum; pro-, meso-, metepisternum, and metasternum smooth, without punctation, sometimes faintly rugose on metepisternum and lateral area of metasterum; metepisternum (Fig. 1 E) distinctly longer than wide (ML/MW = 1.37-1.53, mean 1.47, in seven males and six females); anterior and inner margins bordered; apical margin of abdominal sternite VII slightly emarginate and with two pairs of setae in both sexes.

Legs. Metacoxa with two setae; metafemur with two setae in hind margin; metatarsomere 1 slightly shorter than metatarsomere 2 and 3 combined, about 1.6 times as long as metatarsomere 2; metatarsomere 5 about 1.1 times as long as metatarsomere 1; tarsomere 5 with two setae in each ventrolateral margin.

Male genitalia (Fig. 2 A-I). Median lobe of aedeagus (Fig. 2 A-F) gently curved in lateral view, almost straight in dorsal view; terminal lamella narrow, distinctly longer than wide; apical capitulum present, distinctly protruding ventrally and dorsally, posterior margin of apical capitulum in dorsal view somewhat distinctly emarginate; median part of internal sac in left lateral view (Fig. 2 E) consisting of numerous small spines; internal sac in right lateral view (Fig. 2 F) large hook-shaped, consisting of numerous, dense small spines; ventral side of median lobe not bordered; parameres as in Fig. 2 G, H; sternite IX (Fig. 2 I) not explanate basally.

Female genitalia (Fig. 2 J). Hemisternite with two spines apically; basal stylomere with one preapical spine on external margin; apical stylomere slender with two setae subapically, inner margin almost straight from base to point near subapical setae and slightly curved apically, outer margin gently curved from base to apex, dorsal and ventral outer margins with one small distinct spine, respectively.

Diagnosis

This species can be distinguished from others by the following characters: overall reddish black or brownish black coloration; postgena finely ciliate, penultimate maxillary palpomere distinctly short, about half as long as apical palpomere; pronotum with narrowly rounded basal angle, apical margin completely bordered, lateral margin with faint or without sinuation before basal angle; hind wing fully developed; internal sac of aedeagus in right lateral view (Fig. 2 F) large hook-shaped, posterior margin of apical capitulum in dorsal view somewhat distinctly emarginate.

Distribution

Korea: South (new record); Japan: Kyushu ( Habu 1973), Honshu ( Mori 2016).

Ecology

All the individuals were observed from May to early July and mating behavior was observed in late June. None of the immature adults was observed during the study. Most individuals were observed under the leaf litter in the deciduous forest or at the bottom of the drainage channel, located in the surroundings of the deciduous forest (Fig. 3 A, C).

Notes

Even though the description of T. (B.) nanus by Habu (1961) and Habu (1973) indicates that there are 'no teeth (spines)' in the internal sac, all of the examined Korean male specimens had spines in the internal sac of the aedeagus. Dr. S. Morita kindly sent photography of the aedeagus of the specimen from Osaka (Japan) to the authors for comparison, and it also clearly possessed the spines in the internal sac. The authors conclude that there might be a variation in the presence of the spine in the internal sac of the aedeagus. This species was previously only known to occur in Japan, but a new distribution record is added to Korea.

Figures

Figure 1. Trichotichnus (Bottchrus) nanus Habu, 1954, male: A habitus, dorsal view; B ditto, ventral view; C head and pronotum, dorsal view; D head, ventral view; E metepisternum. Scale bars: 2 mm (A, B); 0.5 mm (C - E).

Figure 2. Male and female genitalia of Trichotichnus (Bottchrus) nanus Habu, 1954: A median lobe of aedeagus, right lateral view; B ditto, dorsal view; C ditto, ventral view; D ditto, left lateral view; E sclerotic armature of internal sac of aedeagus, left lateral view; F ditto, right lateral view; G left paramere; H right paramere; I male sternite Ⅸ; J female genitalia. Scale bars: 0.5 mm (A - D, I); 0.3 mm (E, F, J); 0.2 mm (G, H).

Figure 3. Observation environment and living examples: A observation environment of T. (B.) nanus Habu, T. (T.) miser (Tschitscherine), and T. (T.) vespertinus Habu; B adult of T. (T.) miser (Tschitscherine); C adult of T. (B.) nanus Habu; D immature adult of T. (T.) vespertinus Habu.