Psychristus shibatai
Creators: name: Jaeger, B.
name: H, Ban
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Psychristus
Psychristus shibatai

description: Psychristus (s.str.) shibatai (ITO 1985) (Figs 10-12, 20-21, 25-26, 31)   
 Bradycellus (Taiwanobradycellus) shibatai ITO 1985: 62-63 (type locality: Taiwan: Roshan).   
T y p e m a t e r i a l: The holotype and one male paratype were studied by JAEGER (1997: 72). The remaining paratypes of the type series have been examined more recently:  
P a r a t y p e s: 1 3, 1 ♀ (cITO) labelled "MUSHA / TAIWAN / 20. IV. 1970 / Y. KIYOYAMA", " PARATYPE " [printed on red label], " Bradycellus / (Taiwanobradycellus) / shibatai / (N. ITO)" and " Psychristus (s.str.) / shibatai Ito, 1985 / det. B. Jaeger 2009". The female with additional label "L 87".  
 The original description given by ITO (1985: 62-63) and supplemented by JAEGER (1997: 86-87, 90) with some figures and measurements, included most main characters important for recognition of this species. Thus, only a diagnosis, including characters that differentiate the species from one or more other species of the P. discretus group, additional images and ratios for various body dimensions (see Tables 1 and 2) are presented here.   
 D i a g n o s i s:Thesmallestspeciesinthe P. discretus group with general appearance as figured (Fig. 10). Body length 3.4-3.7 mm and width 1.6 mm. Ground colour of dorsal surface dark reddish brown (one non-type specimen from Taiwan, darker but not yet blackish brown as in P. discretus or P. dentatus), with elytral interval 1, pronotal base and apex medially, lateral margins of pronotum and elytra, labrum, mandibles (base of lateral margin, inner margin and apex blackish) paler reddish. Ventral side, particularly abdomen, sometimes somewhat paler reddish. Legs, antennae and palpi yellowish brown or pale brown. Head (Figs 11-12) including eyes, of medium width, 0.75-0.80 times as wide as pronotum, with eyes distinctly prominent (head 1.64-1.71 times as wide as width between eyes). Apical margin of labrum very weakly emarginated, with a weakly suggested projection medially. Mentum with epilobes (Fig. 31) strongly projecting forward and distinctly acuminate at apices. Mental tooth sharp, its size varies from as long as to half as long as epilobes. Ligular sclerite narrowly rounded at apex. Mandibles of average size, not distinctly prolonged and curved. Antennae 1.72-1.80 times as long as pronotum and 0.60-0.63 times as long as elytra, with antennomere 3 moderately pubescent. Pronotum with shape and punctation as figured (Fig. 11-12), 1.25-1.32 times as wide as long, 1.25-1.33 times as wide as head. Base about 1.17-1.20 times as wide as apical margin between anterior angles and 0.86-0.90 times as wide as maximum pronotal width. Median line moderately to distinctly punctate along its entire length, sometimes in basal third more distinct. Macropterous. Elytra (Fig. 10), 1.47-1.52 times as long as wide, 2.81-2.92 times as long and 1.46-1.58 times as wide as pronotum, with dorsal surface moderately convex (see lateral profile). Humeri more distinctly angulate than in P. discretus, but less than in other species, with humeral tooth small and weakly projecting. Setiferous pore in apical half of interval 3 present. Elytral intervals 2 and 3 relatively flat and almost parallel or faintly dilated in front of apex. Microsculpture on dorsal surface mostly absent, except for isodiametric meshes on labrum, scutellum and on base of elytra anterior to basal margin. Pro- and mesotarsomeres in both sexes ventrally without a dentiform process, protarsomeres 2-4 (perhaps, also 1, but difficult to observe) of males ventrally with typically dilated adhesive hairs. Number and size of spines in pro- and mesotibiae unmodified. Median lobe of aedoeagus short, without apical lamella (Figs 20- 21). Female genitalia as figured (Fig. 25). For ratios representing various body proportions see Tables 1 and 2.   
 C o m p a r i s o n s: In general appearance (Fig. 10) the species is very similar to P. discretus (Fig. 7) and usually differs from the latter by characters given under that species and in the key. However, atypical darker coloured females, if from India, are probably difficult to separate by external characters. The shape of the female hemisternite (Fig. 25) seems to be different (basal half less projecting as in P. discretus) according to two available females from Taiwan, which were compared with females of P. discretus, but additional females of P. shibatai are necessary to verify the constancy of this difference.   
 For separation of P. shibatai from P. brunneus and P. dentatus see these species and key.   
D i s t r i b u t i o n: So far known only from Taiwan and one single record from India, Uttar Pradesh (see Fig. 26).  
In addition to the previously studied type and non-type material (JAEGER 1997: 72-73) and paratypes mentioned in the type section above, one additional female from Taiwan has been studied:  
T a i w a n: Mt. Kwena, IV. 1986, N. Ito (1 – cITO).
description: Published as part of Jaeger, B. & H, Ban, 2009, Two new species of Psychristus subgenus Psychristus ANDREWES 1930 from Southeast Asia, India and Pakistan, with additions to the Psychristus discretus group (Col., Carabidae), pp. 1635-1657 in Linzer biologische Beiträge 41 (2) on pages 1644-1645, DOI: 10.5281/zenodo.5279282