Leiobunum hiraiwai Sato & Suzuki 1939
Creators: name: Tsurusaki, Nobuo
Publisher: name: Zenodo
Year: 2006
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Opiliones
Sclerosomatidae
Leiobunum
Leiobunum hiraiwai

description: Leiobunum hiraiwai (Sato & Suzuki, 1939)
Figs 1–18
Nelima hiraiwai Sato & Suzuki, 1939: 38, figs 3–4. (Type locality: Mt Hikosan, Kyushu, Japan).
Liobunum hiraiwai: Suzuki 1953, figs 4–5; 1957: 109, figs 9–12, 15, 18, 21.
Leiobunum hiraiwai: Suzuki 1966: 160, figs 2F, H: 3F; Tsurusaki & Sasaji 1991: 16, fig. 7C; Tsurusaki 1993: 214; Tsurusaki & Okada 2000: 73, fig. IV­11 (left); Tsurusaki 2002a: 92.
Leiobunum hiraiwai hiraiwai: Suzuki 1976: 237, figs 48–50, 110–111, 252–254, 269, 345–347.
Leiobunum hiraiwai izuense Suzuki, 1976: 239, figs 51–52, 112, 256–257, 270–274, 348–350. (Type locality: Mt Yahazu­yama, Shizuoka Pref.)
Leiobunum hiraiwai fuji Suzuki, 1976: 241, figs 53­58, 113­115, 277­280, 351­352. (Type locality: Lake Yamanaka, Yamanashi Pref.).
Leiobunum hiraiwai shiranense Suzuki, 1976: 244, figs 59–60, 116, 255, 275–276. (Type: ď holotype and 1φ paratype, Shiranesanzan, from Mt Aino­dake to Mt Nôtori­dake, Yamanashi Pref., Z. Ôshimo leg., 27. August 1953, in ZLHU, examined).
Leiobunum hiraiwai longum Suzuki, 1976: 244, figs 61–64, 117, 261–263, 281–284, 353–355. (Type locality: Mt Hyônosen, Tottori Pref.).
Liobunum tamanum Suzuki, 1957: 113, figs 1–3, 5–8, 16, 19, 22, 24–25. (Type locality: Mt Bushû­ Mitake, Tokyo Pref.). NEW SYNONYMY.
Leiobunum tamanum: Suzuki 1976: 232, figs 72–73, 124, 239–244, 340–341; Tsurusaki & Hayashi 1985: 509.
Leiobunum tsushimense Suzuki, 1976: 234, figs 65–66, 245–251, 342–344. (Type: ♂ holotype from Mt Ariake­yama, Tsushima Is., Nagasaki Pref., 7. July 1973, S. Suzuki leg., in ZLHU, examined). NEW SYNONYMY.
Diagnosis. Characterized by the unique shape of the penis shaft with laterally expanded projections (winglets); winglets often barbed (Nos 2–9 in Fig. 16). Palps of both males and females often darkened (This character state is only shared by L. curvipalpe Roewer, 1910; see Tsurusaki 1990).
Description. Male. With medium to large­sized body (3.3–5.9 mm long). Genital operculum as shown in Figs 1C–D, boundary between operculum and 3rd sternite somewhat obscure. Labrum as in Fig. 2, club­shaped, laterally with numerous dark tubercles. Chelicera as in Figs 1I –K, second segment with a few black teeth on its distomesal surface. Palp as shown in Fig. 3; femur moderately curved ventrad, distolaterally with a few teeth; patella distally widened, with a small but distinct apophysis on mesal distal margin; tibia proximally swollen, ventromesally with numerous dark teeth in distal third; tarsus with a distinct ventromesal row of teeth. Palps often completely (Figs 3C–F) or partially (Fig. 3B) darkened; degree of the melanism varying geographically (Fig. 4).
Penis as in Figs 8–16; shape and size variable among populations; shaft widest at base and gradually narrowing toward apex but expanded distally; lateral projections at distal end of shaft ventrally forming a pair of pouches.
Female. Labrum as shown in Figs 1G–H, gradually tapering. Genital operculum (Figs 1E–F) with posterior margin weakly delimited and sharply rounded.
Frequencies of dark­colored and light­colored palps in males of Leiobunum hiraiwai. The upper left box shows different grades of melanism for palpal patella (Pa) and tibia (Ti) in lateral view, which corresponds to the shading of the circles. 1. Light colored. 2–3. Intermediate condition (corresponding to stippled section of circles). 4–5. Dark colored.
Karyotypes (Figs 5–6). Suzuki (1980) briefly reported the existence of three different karyotypes in “ L. hiraiwai ”, which were easily separable by the number of chromosomes (2n = 18, 20 and 22, respectively). To ascertain this, a total of 99 individuals collected from 19 populations were karyologically analyzed by two methods (squash and airdrying). Provenance of material and the results obtained are synoptically presented in Table 1.
Chromosomes were found to vary in number and in morphology among the populations examined. This phenomenon was already reported by Suzuki (1980). Interestingly, an obvious eastward increase in the number of chromosomes from 2n = 18 (Mt Hikosan population) to 2n = 22 (Mt Bushû–Mitake, Mt Amagi and Mt Kiyosumi populations) was observed (see Figs 7, 17). Of diploid complement, the X and Y chromosomes were usually the largest or the smallest chromosomes, respectively, although some variants were found. Characteristics of these karyotypes are mentioned in the descriptions of races below.
description: Published as part of Tsurusaki, Nobuo, 2006, Geographic variation of chromosomes and somatic morphology in the Japanese polymorphic species Leiobunum hiraiwai (Arachnida: Opiliones: Sclerosomatidae), pp. 157-190 in Zootaxa 1325 on pages 160-163, DOI: 10.5281/zenodo.174045