VENUS 66 (3-4): 127-145, 2008

Systematic Revision of the Subgenus Luchuhadra (: Camaenidae: Satsuma) Occurring in the Central Ryukyu Archipelago

Yuichi Kameda* and Makoto Kato Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-Nihonmatsu- cho, Sakyo, Kyoto 606-8501, Japan;* [email protected]

Abstract: Satsuma (Luchuhadra) largillierti is an arboreal endemic to Okinawa Island, Japan, and its extensive geographic variation in shell morphology has long caused taxonomic confusion. A recent molecular phylogenetic study demonstrated that S. largillierti and the two endemic to Okinoerabu Island, S. erabuensis and S. sooi, are more correctly re-organized into two species that are anatomically and genetically distinct. To confirm the taxonomic status and nomenclature of these species, we examined the available type materials and corresponding descriptions. We suggest that the above species be treated as S. eucosmia and S. largillierti, that S. sooi become a of S. largillierti, and that S. erabuensis is reduced to a subspecies of S. eucosmia. We also present revised morphological descriptions of the four Luchuhadra species that range from Iheya Island off Okinawa Island to the Miyako Islands, which are here confirmed as distinct based on both morphological and molecular data.

Keywords: discriminant analysis, genital morphology, Satsuma amanoi, Satsuma hemihelvus, Satsuma iheyaensis, Satsuma omoro

Introduction

The subgenus Luchuhadra (Camaenidae: Satsuma) is an arboreal group of land snails endemic to the middle Ryukyu Archipelago in the southwestern part of Japan. Luchuhadra currently consists of 11 extant species (Minato, 1988), which are regarded as having largely distinct morphologies (Minato, 1976, 1980, 1982a, 1984, 1987; Azuma, 2000). Among them, Satsuma largillierti exhibits great variation in shell shape, shell color pattern, and anatomy, which has raised speculation concerning the specific status of different varieties (Chinen, 1977; Azuma, 1982, 1995; Azuma, 2000; Minato, 1995). Kameda et al. (2007) performed genetic and morphometric analyses on these snails and found that S. largillierti and the two species endemic to Okinoerabu Island, S. erabuensis and S. sooi, compose two distinct biological species, Group E and L, that do not agree with the current circumscriptions (Fig. 1). Satsuma largillierti was divided into two morphologically and genetically distinct species with largely allopatric distributions (Fig. 2). In addition, our genetic analysis and morphometric reassessment did not support the separation of S. erabuensis and S. sooi, except for the shell shape of S. erabuensis. Thus we concluded that these two species should be included in one of the two cryptic species of S. largillierti (Kameda et al., 2007). Here we aim to reassess the specific status of the S. largillierti species complex (including S. sooi and S. erabuensis). We also present revised morphological descriptions of the four related species distributed from Iheya Island to the Miyako Islands.

Institutional abbreviations: ANSP, Academy of Natural Sciences, Philadelphia; NC, Nishinomiya Shell Museum; NSMT, National Museum of Nature and Science, Tokyo. 128 Y. Kameda & M. Kato

S. sororcula S. adelinae S. shigetai S. tokunoshimana S. iheyaensis S. amanoi S. eucosmia (including S. erabuensis) S. largillierti (including S. sooi) S. omoro S. hemihelvus outgroup

Fig. 1. Phylogenetic relationships among Luchuhadra species based on mitochondrial COI sequences (redrawn from Kameda et al., 2007).

Materials and Methods

Sampling To reaffirm the morphological circumscription of the Luchuhadra species, we sampled snails from all currently recognized species. In total, we obtained 398 adult Luchuhadra snails. The sampling sites and sample sizes are shown in Appendix. Four species from Amami-Oshima and Tokunoshima Islands, S. sororcula, S. adelinae, S. shigetai and S. tokunoshimana, are not discussed in this paper because our preliminary analysis of morphology and genetic data indicates that their specific status may require further investigation. Some of the specimens used in this study were deposited in the NSMT, and others have been retained in the collection of the first author.

Classification of type specimens Satsuma largillierti, S. erabuensis and S. sooi are clustered in two distinct lineages, Group E and L, each of which is further subdivided into five (Eb, Ef, Eg, Es, and Ee [= S. erabuensis]) and eight (Lh, Li, Lk, Lm, Lu, Ly, Lz, and Y [= S. sooi]) well-supported subgroups (Kameda et al., 2007). According to Minato (1988), six names have been given to this species group: Helix largillierti Pfeiffer, 1849, Helix immaculata Adams & Reeve, 1850, Ganesella largillierti var. eucosmia and var. zacosmia Pilsbry, 1895, Satsuma erabuensis Minato, 1978, and Satsuma sooi Minato, 1982. To confirm the nomenclature of this species complex, we examined the type materials of G. largillierti var. eucosmia and var. zacosmia, S. erabuensis, and S. sooi. We also examined the type material of S. yoronjimana, a fossil species from Yoron Island, because it is possible that this species belongs to one of the two groups, E or L. Discriminant analysis was used to determine to which group each type series corresponds. The analysis was performed using the CANDISC procedure of SAS software (SAS Institute). The following characters were measured from either digital or printed images: shell height, shell width, spire height, spire width, aperture height, aperture width, and inner lip length. Because shell measurements cannot be used to confidently distinguish species (Kameda et al., 2007), we also considered the angularity of the periphery and color pattern. The assignment of H. largillierti and H. immaculata were based on Systematic Revision of the Subgenus Luchuhadra 129

A Lh B Eb Ly Li Lk

Ly Eg Lm Li Ef

Lu

Lz

Es

10km

Fig. 2. Distributions of Satsuma largillierti (A) and S. eucosmia eucosmia (B) on Okinawa Island. The shaded regions represent the distributions of mitochondrial subgroups within each species. See text for abbreviated codes applied to subgroups. the original descriptions because we were unable to locate the type material.

Systematics

Family Camaenidae Pilsbry, 1895 Genus Satsuma Adams, 1868 Subgenus Luchuhadra Kuroda & Habe, 1949

Satsuma (Luchuhadra) largillierti (Pfeiffer, 1849) (Figs. 3A-D, 5A-B)

Helix largillierti Pfeiffer, 1849: 78-79; Tryon, 1887: 218, pl. 50 fig. 45-46. Helix immaculata Adams & Reeve, 1850: 62, pl. 16, fig. 5. Eulota (Euhadra) largillierti: Gude, 1900: 77. Satsuma (Luchuhadra) largillierti: Habe, 1955: 221-222, fig. 5; Minato, 1988: 145. Luchuhadra largillierti: Kuroda, 1960: 48; Kuroda, 1963: 46. Luchuhadra adelinae: Chinen, 1977: 134, pl. 3, fig. 18 (non Ganesella adelinae Pilsbry, 1901). Satsuma sooi Minato, 1982a: 188, 190-191, pl. 1, fig. 4. Satsuma (Luchuhadra) sooi: Minato, 1987: 38, pl. 2, figs. 3-4; Minato, 1988: 146; Yukita, 2003: 78, 161. 130 Y. Kameda & M. Kato

A B C D

E F G H

I J K L 10 mm

Fig. 3. Shells of the Luchuhadra species. A-D. Satsuma largillierti; A, subgroup Lz (Kameda Collection [KC] No. 2854), this individual agree well with the description of Pfeiffer (1849); B, subgroup Li (KC No. 2366); C, subgroup Ly (KC No. 3833); D, subgroup Lu (NSMT-Mo 73960). E-G. S. eucosmia eucosmia; E, lectotype of Satsuma eucosmia eucosmia (ANSP 70803); F, lectotype of Ganesella largillierti var. zacosmia Pilsbry, 1895 (ANSP 70802); G, specimen without bands (KC No. 2389). H. S. eucosmia erabuensis (lectotype, ANSP 89996). I. S. iheyaensis (NSMT-Mo 73940). J. S. amanoi (NSMT- Mo 73939). K. S. omoro (NSMT-Mo 73942). L. S. hemihelvus (NSMT-Mo 73933). A B ps ap ps ap

ep ep

C a D a

ps b ps b ep ep

Fig. 4. The external and internal structures of the penis sheath and the appendix of the penis of Satuma eucosmia eucosmia (A, B) and S. omoro (C, D). In S. omoro, the small projection (a) is usually regarded as the appendix of the penis. The thick part between the projection and epiphallus (b) has been considered as a part of the epiphallus, but the internal structure is similar to that of the appendix of the penis in S. e. eucosmia. See text for letters indicating anatomical parts. Systematic Revision of the Subgenus Luchuhadra 131

Satsuma (Luchuhadra) yoronjimana Azuma & Azuma, 1990: 198-200. Luchuhadra sooi: Azuma, 1995: 212-213, pl. 74, fig. 629. Luchuhadra yoronjimana: Azuma, 1995: 213, pl. 74, fig. 631.

Type material: Not located. Type locality: Liew-Kiew (= Ryukyu). Original description: “T. perforata, subtrochiformis, tenuis, sublaevigata, diaphana, albida; spira conica, obtusiuscula; anfr. 5½ vix convexiusculi, ultimus peripheria obsolete angulatus; apertura obliqua, rotundato-lunaris; perist. simplex, margine dextro breviter expanso, basali subincrassato, columellari dilatato, reflexo, umbilicum angustissimum semiegente. -Diam. maj. 22, min. 20, alt. 17 mill. (Coll. Phillipi.)”. Redescription: The shell is small- to large-sized for Luchuhadra, approximately 15-29 mm in diameter. The size of the shell and the angularity of the periphery show a high degree of geographic variation. The spire is tall, but the shell height seldom or never exceeds the diameter. The number of whorls is 5.5-6.5. The protoconch consists of two whorls. The shell surface is smooth, pale or yellowish-white without bands, or occasionally with light brown to black bands at the periphery, sutures, and umbilicus. A few individuals exhibit two color bands at the periphery. The aperture is roundly lunate. The outer and basal lips are narrowly reflexed. Half or more of the umbilicus is covered by the columellar reflection, but it is not completely closed. The hermaphroditic gonad is embedded in the digestive caecum and usually consists of four clusters of alveoli. The hermaphroditic duct is long and folded. The albumen gland (ag) is rather large. The spermoviduct (sod) is well developed and twists around the peduncle of the bursa copulatrix (pd) in many individuals (111 of 144 observations). The free oviduct (od) is short, usually less than 7 mm in length. The vagina (vg) is rather long and slightly thickened at the proximal end. The vas deferens (vd) is slender and simple; it runs down the vagina, attaches to the terminal region of the penis sheath (ps), and then connects to the epiphallus (ep). The epiphallus is well developed but short, less than two-thirds of the penis sheath. The flagellum (fl) is short, usually less than 5 mm, and slenderizes abruptly within the proximal half of its length. The penis sheath is rather long, slightly thickened at the proximal end. The appendix of the penis (ap) is rather small and slightly thickened, with a rounded end. Distribution (Fig. 2A): The southern limit of the distribution is Urasoe on the western side of Okinawa Island, and Kita-nakagusuku on the eastern side. This species occurs on Henza, Miyagi, Ikei, Sesoko, Ie, Kouri, Yagaji and Okinoerabu Islands, and from the middle to the northern part of Okinawa Island, with discontinuous distribution. In the northern part of Okinawa and Okinoerabu Islands, some populations are sympatric with S. eucosmia. Notes: This species corresponds to Group L in Kameda et al. (2007). Although Minato (1987) reported that S. sooi has a long flagellum, the specimens used in our study had relatively short flagella, which were within the range of variation for Group L on Okinawa Island. Although the shell is relatively flat compared to that of S. eucosmia eucosmia and tends to show different color patterns, discriminating between the two species is difficult based on shell morphology. This species is easily distinguished from S. eucosmia by its thin vagina and the appendix of the penis, longer penis sheath and shorter epiphallus and flagellum. The spirally-twisted spermoviduct is a unique character of this species. 132 Y. Kameda & M. Kato

Satsuma (Luchuhadra) eucosmia eucosmia (Pilsbry, 1895) (Figs. 3E-G, 5C-D)

Ganesella largillierti: Pilsbry, 1895: 161; Hirase, 1951: pl. 124, fig. 26; Hirase & Kuroda, 1954: 1042, fig. 2945 (non Helix largillierti Pfeiffer, 1849). Ganesella largillierti var. immaculata: Pilsbry, 1895: 161, pl. 10, fig. 12 (non Helix immaculata Adams & Reeve, 1850). Ganesella largillierti var. eucosmia Pilsbry, 1895: 161, pl. 10, fig. 14. Ganesella largillierti var. zacosmia Pilsbry, 1895: 161, pl. 10, fig. 13. Satsuma (Luchuhadra) largillierti: Kuroda & Habe, 1949: 59-60, pl. 1, fig. 11; Shikama, 1964: pl. 15, fig. 17; Chinen, 1968: 40-41, figs. 15-17; Azuma, 1982: 192, 283 f. 373, pl. 34, fig. 373; Minato, 1986: 258; Kubo & Kurozumi, 1995: 234-235; Minato, 2004: 258 (non Helix largillierti Pfeiffer, 1849). Luchuhadra largillierti: Chinen, 1977: 134, pl. 3, figs. 12, 13-16; Maeda et al., 1987: 29, pl. 15, fig. 246; Azuma, 1995: 128, 266, fig. 373, pl. 34, fig. 373 (non Helix largillierti Pfeiffer, 1849). Satsuma largillierti: Okutani & Habe, 1983: 51, 192; Okutani, 2006: 49 (non Helix largillierti Pfeiffer, 1849).

Type material: Lectotype, ANSP 70803; selected by Baker (1963: 245). Type locality:‘ Yaeyama’ (Okinawa) Island. The lectotype was most likely collected from the southern part of Okinawa Island. Pilsbry (1895:160) specifically used the name‘ Yaeyama’ to refer to Okinawa Island, and distinguished it from the Yaeyama Islands in southwestern Okinawa Prefecture. Redescription: The shell is medium- to large-sized for Luchuhadra, approximately 21-30 mm in diameter. The shell height often exceeds shell diameter. The number of whorls is 5.5-7. The periphery of the whorl is weakly angulate. The aperture is roundly lunate. The outer and basal lips are narrowly reflexed. Half or more of the umbilicus is covered by the columellar reflection but it is not completely closed. The shell exhibits three basic color patterns: (1) a pale white shell, with a yellowish sutural margin and base; (2) two strong or weak bands of color on the periphery, and (3) dark bands above and below the periphery, fading into yellowish-red toward the suture and base. The last pattern sometimes lacks color gradation. Some individuals from the northern part of Okinawa Island exhibited several additional color patterns. The hermaphroditic gland is embedded in the digestive caecum and usually consists of four clusters of alveoli. The albumen gland (ag) is rather large. The spermoviduct (sod) is well developed and parallel to the peduncle of the bursa copulatrix (pd). The free oviduct (od) is short. The vagina (vg) is rather short, and strongly thickened at the proximal area. The flagellum (fl) is tapering and rather long, usually longer than 5 mm. The epiphallus (ep) is long and well developed; it is at least two-thirds the length of the penis sheath (ps), if not longer. The proximal part of the sheath widens and continues into the appendix of the penis (ap), which is large, thick, and rather cuspate. Distribution (Fig. 2B): This subspecies occurs on Hamahiga Island and throughout Okinawa Island, except the Motobu Peninsula and the central part of the island from Yomitan and Uruma to Urasoe and Okinawa City. The distribution of this subspecies is thus separated into two disjunct areas. The southern distribution overlaps with the range of S. amanoi, and they sometimes coexist. Notes: This subspecies corresponds to Group E in Kameda et al. (2007), of which Subgroup Es is the nominotypical population of S. eucosmia. The northern and southern populations are slightly divergent in genital morphology. The genital morphology of the northernmost populations (Subgroup Eb and the northern populations of Subgroup Ef) resembles that of S. adelinae, but it is distinguishable by the thickness of the appendix of the penis and the attachment site of the Systematic Revision of the Subgenus Luchuhadra 133 retractor muscle of the penis (rm; usually less than one-fifth of the length of the epiphallus from the distal end, compared to one-quarter to one-third the length in S. adelinae).

Satsuma (Luchuhadra) eucosmia erabuensis Minato, 1978 (Figs. 3H, 5E)

Ganesella sororcula okinoerabuensis Pilsbry & Hirase, 1905: 709 (preocupied by Satsuma mercatoria okinoerabuensis = Eulota okinoerabuensis Pilsbry & Hirase, 1904). Luchuhadra erabuensis Kuroda, 1963: 46, No. 776 (nomen nudum); Azuma, 1995: 129-130, pl. 34, fig. 377. Satsuma erabuensis Minato, 1978: 5-6 (new name for G. okinoerabuensis); Minato, 1982a: 187-188, pl. 1, figs. 1-3. Satsuma (Luchuhadra) erabuensis: Azuma, 1982: 193, pl. 34, fig. 377; Minato, 1986: 258-259; Minato, 1988: 146; Yukita, 2003: 78, 161; Minato, 2004: 258.

Type material: Lectotype, ANSP 89996; selected by Baker (1963: 246). Type locality: Okinoerabushima, Osumi. Original description by Pilsbry & Hirase (1905): “Narrowly umbilicate, broad and low-conic, light yellow with a broad purplish-brown band immediately above and another a short distance below the periphery. Spire bicolored, the lower half of the penultimate whorl purple-brown, the upper half yellow; on the next earlier whorl purple replaces the yellow; and the upper two whorls are dark purple-brown. The surface is finely striate spirally.” Observation: The shell morphology observed in this study is consistent with the description by Pilsbry & Hirase (1905). The shell is thick and large for the subgenus, approximately 26-30 mm in diameter, and relatively flat. The shell height (19-26 mm) does not exceed the diameter. The number of whorls is 5-6. There is no polymorphism in shell color. Genital morphologies are almost identical to those of the previously mentioned subspecies, especially the northern populations. Distribution: This subspecies occurs on Okinoerabu Island. It is sympatric with one population of S. largillierti (i.e., at Uchijiro, Wadomari). Notes: This subspecies is distinguishable from the nominotypical subspecies by its flatter shell and shell color. Minato (1982a) reported that the enlarged appendix of the penis and the thickened vagina are important characters of this subspecies, but they fall within the range of geographic variation within S. eucosmia (Kameda et al., 2007).

Satsuma (Luchuhadra) iheyaensis (Pilsbry & Hirase, 1905) (Figs. 3I, 5F)

Ganesella sororcula iheyaensis Pilsbry & Hirase, 1905: 710. Luchuhadra largillierti iheyaensis: Kuroda, 1960: 48 No. 1429. Luchuhadra iheyaensis: Kuroda, 1963: 46; Azuma, 1995: 130; Azuma, 2000: 85-87. Satsuma iheyaensis: Minato, 1982b: 33-34. Satsuma (Luchuhadra) iheyaensis: Azuma, 1982: 194; Minato, 1988: 146.

Type material: Lectotype, ANSP 89981; selected by Baker (1963: 246). Type locality: Iheyajima, Ryukyu. Original description: Shell globose-trochiform, minutely obliquely perforate, pale yellowish (or white when denuded of the thin cuticle) with three red-brown bands, one at the periphery, one above and one below it, the latter sometimes concrescent with the peripheral; there is also a dark 134 Y. Kameda & M. Kato

A vg B vg ps ps od ap vd od vd fl ap rm sod fl

bc pd ep rm sod ep pd ag ag bc

E ps ap vg vd

rm od

fl ep ag

pd sod

bc D C vg vg ps ps ap od vd ap od vd

fl pd sod rm sod rm

ep pd fl ep ag ag bc

bc

Fig. 5. Genital structures of Luchuhadra snails. A. Satsuma largillierti, Nuuha, Ogimi. B. S. largillierti, Uchijiro, Okinoerabu Island, formerly S. sooi. C. S. eucosmia eucosmia, Nakagusuku, Nakagusuku. D. S. eucosmia eucosmia, Benoki, Kunigami. E. S. eucosmia erabuensis, Uchijiro, Okinoerabu Island. Systematic Revision of the Subgenus Luchuhadra 135

G F vg vg ps pd vd

od od pd ap rm

vd fl ap

fl ep sod rm sod

ep bc ps ag

bc ag

H I ps ps ap vg ap vg vd od vd fl rm

rm od pd ep pd ep fl

bc sod bc sod

ag ag

Fig. 5 (continued). F. Satsuma iheyaensis, Mt. Gayozan, Iheya Island. G. S. amanoi, Hyakuna, Tamagusuku. H. S. omoro, Aka, Kume Island. I. S. hemihelvus, Mt. Nobaru, Miyako Island. Abbreviations: ag, albumen gland; ap, appendix of the penis; bc, bursa copulatrix; ep, epiphallus; od, oviduct; ps, penis sheath; rm, retractor muscle of the penis; pd, peduncle of the bursa copulatrix; sod, spermoviduct; fl, flagellum; vd, vas deferens; vg, vagina. Scale = 10 mm. See letters indicating anatomical parts. 136 Y. Kameda & M. Kato subsutural line, and a small umbilical dark area. Spire convex-conic with obtuse apex; whorls 5½, the last angular peripherally. Basal lip thickened within. Observation: The conchological features observed in this study are almost identical to the original description. In addition to the above banding patterns, some snails have one broad band on the periphery, whereas others lack color bands. The basic structure of the genitalia is similar to that of S. largillierti. The spermoviduct (sod) is well developed and parallel to the peduncle of the bursa copulatrix (pd). The vagina (vg) is rather short (approximately 14 mm in length) and slightly thickened at the proximal end. The flagellum (fl) is medium length and tapered. The epiphallus (ep) is well developed, and three- quarters the length of the penis sheath (ps). The penis sheath is rather long, approximately 20 mm in length; it is somewhat thickened at the proximal and the distal end, but slender in the middle. The appendix of the penis (ap) is small but conspicuous, tapered, and hooked at the tip. Distribution: This species had been found only at the top of Mt. Gayozan, Iheya Island. However, the distribution range may be broader than previously believed; we collected live snails and several empty shells near the foot of the mountain. Notes: This species is characterized by its strongly angulated shell. The genital morphology is similar to that of S. largillierti, but differs in the following characteristics: in S. iheyaensis, the appendix of the penis is hooked, the flagellum is longer and tapered, the length of the epiphallus relative to the penis sheath is greater than that of S. largillierti, and the spermoviduct is not spirally twisted. Some individuals of S. eucosmia from the northern part of Okinawa Island also have a hooked appendix of the penis, but the critical difference is the thickness of the appendix and the vagina.

Satsuma (Luchuhadra) amanoi Kuroda, 1960 (Figs. 3J, 5G)

Satsuma (Luchuhadra) amanoi Kuroda, 1960: 48, 80, pl. 3, fig. 31; Chinen, 1968: 41, figs. 20-21; Azuma, 1982: 192-193, 283, fig. 374, pl. 34. fig. 374; Minato, 1986: 258-259; Minato, 1988: 147; Kubo & Kurozumi, 1995: 231; Minato, 2004: 258. Luchuhadra amanoi: Kuroda, 1963: 46, No. 778; Chinen, 1977: 134, pl. 3, fig. 11; Azuma, 1995: 128-129, 266, fig. 374, pl. 34, fig. 374. Satsuma amanoi: Minato, 1976: 83-84, pl. 1, figs. 2-3.

Type materials: Holotype, NC-H067. Type locality: Hyakuna, Tamashiro-son (Tamagusuku), Okinawa Observation: The shell is medium-sized for the subgenus, approximately 19-22 mm in diameter, with a high, conical spire. The number of whorls is 6-7, and the periphery is weakly angulated. The shell surface is smooth and opalescent, with no color bands. The outer and basal lips are narrowly reflexed. The umbilicus is open, but mostly covered by the columellar reflection. The basic structure of the genitalia is similar to that of S. largillierti. The spermoviduct (sod) is well developed and parallel to the peduncle of the bursa copulatrix (pd). The vagina (vg) is rather thick, medium in length, and somewhat thickened at the proximal end. The flagellum (fl) is tapered and medium in length. The appendix of the penis (ap) is small and slender, but longer than the flagellum. The penis sheath (ps) is extremely long (48-102 mm). The proximal third and the distal end are somewhat thickened, whereas the distal two-thirds is nearly as slender as the vas deferens (vd). Distribution: This species inhabits the southern part of Okinawa Island, and often co-occurs with S. e. eucosmia. Notes: This species is characterized by its white, high-spired shell and extremely long penis Systematic Revision of the Subgenus Luchuhadra 137 sheath. Kuroda (1960) and Minato (1976) mentioned the relationship between this species and S. albida, a Taiwanese arboreal species. However, our phylogenetic analyses do not support a close relationship between S. albida and Luchuhadra (Y. Kameda et al., unpubl. data). The similarity in shell shape observed in these two species is likely the result of convergence.

Satsuma (Luchuhadra) omoro Minato, 1982 (Figs. 3K, 5H)

Satsuma omoro Minato, 1982a: 188-190, figs. 1-4, pl. 2, figs. 1-4. Satsuma (Luchuhadra) omoro: Minato, 1988: 147. Luchuhadra omoro: Azuma, 1995: 213, 294, fig. 630, pl. 74, fig. 630.

Type materials: Holotype, NSMT-Mo 59541. Type locality: Between Gushikawa and Kitabaru, Gushikawa Village, Okinawa. Observation: The conchological features are similar to those of S. largillierti. The shell is medium in size, approximately 22-27 mm in diameter. The shell diameter is usually larger than shell height. The number of whorls is 5.5-6, and the periphery of the whorl is weakly angulated. The shell surface is smooth, yellowish-white, and exhibits several color patterns similar to those observed in S. e. eucosmia and S. largillierti. The basic structure of the genitalia is also similar to that of S. largillierti. The spermoviduct (sod) is well developed and parallel to the peduncle of the bursa copulatrix (pd). The vagina (vg) is long, approximately 25-35 mm, and thickened at the proximal end. The flagellum (fl) is tapered and medium in length. The epiphallus (ep) is well developed but short (less than 9 mm in length) and continues into the appendix of the penis (ap), which appears to be an extension of the epiphallus. The appendix of the penis is thick, rather flat, and the apex is weakly projected. The penis sheath (ps) is shorter than the vagina (20-24 mm), and becomes flattened at the proximal end. The interior plicae can be seen through the appendix of the penis and at the beginning of the penis sheath. Distributions: Kume Island. Notes: The “epiphallus” of this species seems to thicken towards the distal end, and continues into the papilliform “appendix of the penis” (as described by Minato, 1982a, and Azuma, 2000). However, this thickened part is the basal area of the appendix of the penis, because the internal structure is homologous to that of the appendix of the penis in other species (Figs. 4A-D; Emura, 1933). In S. omoro, the slender part of the “epiphallus” runs into the thickened part, which consists of two fleshy plicae internally, and reaches the tip of the small projection (Figs 4A, B). In contrast, in other species the epiphallus runs directly into the lateral side of the appendix of the penis (Figs. 4C, D). The penis sheath of S. omoro seems to be attached near to the tip of the appendix of the penis, which may represent an intermediate stage on the way to losing this appendix.

Satsuma (Luchuhadra) hemihelvus Minato, 1980 (Figs. 3L, 5I)

Satsuma hemihelvus Minato, 1980: 90-91, 95, pl. 1, figs. 3-4, pl. 2, figs. 7-8. Satsuma (Luchuhadra) hemihelvus: Minato, 1986: 258-259; Minato, 1988: 146, pl. 7, fig. 4; Minato, 2004: 258. Luchuhadra hemihelvus: Maeda et al., 1987: 29, pl. 15, fig. 245; Azuma, 1995: 212, 293, fig. 628, pl. 74, fig. 628. 138 Y. Kameda & M. Kato

Type material: Holotype, Minato Collection No. 20414. Type locality: Tomiyapiazu-utaki, Irabu Island, Miyako Islands. Observation: The conchological features are similar to those of the previously described species. The shell is thin and medium-sized for Luchuhadra, approximately 22-26 mm in diameter. The shell diameter is greater than shell height (18-23 mm). The number of whorls is 5.5-6, and the periphery of the body whorl is rounded. The shell surface is smooth, opaque white with a yellow base, and it usually has dark brown bands on the periphery and the suture. Some individuals lack the color bands. The basic structure of the genitalia is also similar to that of S. largillierti. The free oviduct (od) is exceedingly long (12-24 mm), folded near the basal part of the peduncle of the bursa copulatrix (pd), but not spirally twisted. The vagina (vg) is somewhat short, usually less than 17 mm in length, and thickened at the proximal end. The flagellum (fl) is thin, tapered, and medium in length (5-7 mm). The epiphallus (ep) and the penis sheath (ps) are fairly long, up to 42 mm and 39 mm, respectively. The epiphallus is longer than the penis sheath. The appendix of the penis is thickened and rather large. Distribution: Miyako and Irabu Islands in the Miyako Islands. Notes: Minato (1980) noted that this species is characterized by a very long appendix of the penis and thickened peduncle of the bursa copulatrix. However, the most striking characteristic of this species is the exceedingly long oviduct. The lengths of the penis sheath and the epiphallus are also distinctive.

Discussion

Taxonomic status A previous phylogenetic study of Luchuhadra supported the distinctiveness of S. iheyaensis, S. amanoi, S. omoro, and S. hemihelvus (Kameda et al., 2007). We consider them well-defined species because the genital morphology of each is also unique (see above). On the other hand, the four species from the Amami Islands were grouped into two monophyletic groups, but none of them were demonstrated to be monophyletic (Y. Kameda et al., unpubl. data). Further study is needed to determine the specific status of these species, and thus we did not discuss them in this paper. The remaining three species, S. largillierti, S. erabuensis and S. sooi, compose two distinct biological species, Group E and L (Kameda et al., 2007). Group E consists of five subgroups with relatively deep divergence based on mitochondrial cytochrome oxidase I (COI) gene sequences. However, there are no clear morphological differences between these subgroups (except for the shell morphology of Subgroup Ee, which corresponds to the traditional description of S. erabuensis), and they were not clearly separated by the nuclear internal transcribed spacer (ITS) sequences. Thus, these five subgroups, including S. erabuensis, are conspecific because of the lack of differentiation in nuclear sequences and morphology (Kameda et al., 2007). Nevertheless, we treat S. erabuensis as a subspecies of Group E. Criteria for recognizing subspecies are traditionally based on morphological uniqueness and geographic isolation from the nominal type population (Haig et al., 2006). More recently, evidence from genetic data is increasingly used as a basis of determining subspecies (Elejalde et al., 2005; Haig et al., 2006). Our treatment of S. erabuensis as a subspecies of S. eucosmia is consistent with these criteria; it is distinct in terms of shell morphology, it is isolated on Okinoerabu Island, and there are clear genetic differences in the COI gene sequences. Group L is subdivided into eight mtDNA subgroups, which were less divergent than those in Group E. Shell and genital morphologies were very similar and continuous among the subgroups, Systematic Revision of the Subgenus Luchuhadra 139 including S. sooi (Kameda et al., 2007). Discriminant analysis classified two type materials of S. sooi into Subgroup Ly (Table 1), which is distributed across the northern part of Okinawa Island. This supports the morphological similarity of S. sooi to the rest of the subgroups. It is reasonable to state that S. sooi and all other subgroups of Group L are conspecific. Although we treat only one subgroup as a subspecies, all subgroups are equally important as evolutionary entities and must be taken into account when considering the conservation of these snails. The fossil taxon S. yoronjimana has been considered a distinct species restricted to Yoron Island, which is located between Okinoerabu and Okinawa Islands. The fossil and extant fauna of land snails from this island were reported by Minato (1978), Kurozumi (1984), and Azuma & Azuma (1990). These fauna, including the extinct species, are also found on Okinoerabu and Okinawa Islands (Minato, 1978; Tomiyama, 1983), and except for S. yoronjimana, no endemic species were noted (Zaptyx yoronjimana is conspecific with Z. hyperoptyx, ranging from Okinoerabu Island to the Kerama Islands; Minato, 1994). Because the island is within the range of both Group E and L, it is reasonable to assume that S. yoronjimana is conspecific with either Group E or L. The result of the discriminant analysis (Table 1) suggests that S. yoronjimana is likely an extinct population of Group L.

Nomenclatural consideration To confirm the nomenclature of Group E and L, we consulted the original descriptions and type materials of the corresponding species names. In the original description of Helix largillierti, Pfeiffer (1849) mentioned that the shell is white without color bands, and that the shell diameter is 22 mm and 17 mm in height. This specimen likely belongs to Group L, because the shell is small and flat, and its measurements are out of the range of Group E. Whereas the individuals of Group L have opaque to pale white shells (Figs. 3A-D), the shells of Group E snails retain a yellowish epidermis on both the sutures and the base (Fig. 3G). The latter criterion is also applicable to specify Helix immaculata, which had a “blue white shell, with the remains of a slight epidermis about the sutures” (Adams & Reeve, 1850). Thus, both species names correspond to Group L, and largillierti is the valid specific name of this species. Helix immaculata, Satsuma sooi, and Satsuma (Luchuhadra) yoronjimana are junior synonyms of H. largillierti. On the other hand, Pilsbry (1895) treated immaculata, eucosmia, and zacosmia as varieties of Ganesella largillierti. The lectotypes of eucosmia and zacosmia are shown in Figs. 3E and 3F. Discriminant analysis classified both specimens into Subgroup Es (Table 1). The second candidate

Table 1. Result of discriminant analysis performed on type materials (Wilks’Λ=0.02319, F=14.85, P<0.0001). Classification (probability) Corresponding name Specimen D (mm) H (mm) first second candidate candidate Helix largillierti - 22 17 (L) Helix immaculata - - - (L) Ganesella largillierti Lectotype 27.0 25.5 Es (85.6%) Li (14.1%) var. eucosmia Ganesella largillierti Lectotype 25.0 23.7 Es (61.2%) Li (37.3%) var. zacosmia Satsuma erabuensis Lectotype 27.8 21.8 Ee (77.4%) Lu (17.7%) Satsuma sooi Holotype 18.2 16.3 Ly (82.2%) Y (16.4%) Paratype 19.0 17.0 Ly (87.4%) Y (12.0%) Satsuma (Luchuhadra) Holotype 22.5 20.0 Ly (47.7%) Y (31.0%) yoronjimana 140 Y. Kameda & M. Kato for the two shells was Subgroup Li, but this is clearly incorrect because the shells of Subgroup Li have a rather rounded periphery and do not exhibit the color patterns observed in the lectotypes. The shell shape and color pattern of the lectotypes match those of Subgroup Es. Thus, these names correspond to Subgroup Es. The discriminant analysis classified the lectotype of Satsuma erabuensis into Subgroup Ee, i.e., the currently recognized S. erabuensis (Table 1). Thus, the specific name of Group E is eucosmia, and S. erabuensis should be referred to as S. eucosmia erabuensis.

Acknowledgements

We thank Dr. Hiroshi Minato (Shirahama, Wakayama Prefecture) for his valuable advice on the type material of S. e. erabuensis; Mr. Paul Callomon (Academy of Natural Sciences, Philadelphia) for sending photographs of Pilsbry’s lectotypes; Dr. Hiroshi Saito (National Science Museum, Tokyo) for depositing and examining the specimens in NSMT; Dr. Terufumi Ohno (Kyoto University Museum) for examining the specimens in the museum; Ms. Ayako Ogata (Tsudoi Company) for the information on S. eucosmia in Onna Village; Mr. Toru Kato, Dr. Hiroki Hata, and Mr. Masaki Hoso for sample collection; Ms. Tomoko Okamoto for sample collection and help in the field; and Dr. Atsushi Kawakita for sample collection, technical support, and helpful comments on this study.

References

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(Received March 30, 2007 / Accepted July 25, 2007) 142 Y. Kameda & M. Kato

Appendix. Sampling information of specimens used in this study. Sample size Species Locality Voucher specimens Shell Genitalia S. largillierti Uchijiro, Wadomari Town 9 8 2899-2900, 3724, 3725 (=NSMT-Mo 73935), 3726, 3727(= NSMT-Mo 73936), 3728-3729, soo-kw1-3* Hedo, Kunigami Village 8 10 1998, 2349-2350, 2414, 3679-3682, 3809, 3959 Mt. Hedo-Ishiyama 8 9 2235, 3686-3690, 3834-3836 Yona, Kunigami Village 7 8 2901, 3663, 3811-3814, 3963-3964 Iji, Kunigami Village 5 5 3821-3825 Hentona, Kunigami 6 5 3838-3843 Village Hiji, Kunigami Village 7 8 2857, 3697-3698, 3815-3819 Janagusuku, Ogimi 7 7 2379-2383, 3696, 3982 Village Shirahama, Ogimi Village 5 5 2369-2370, 3695, 3827-3828 Taiho, Ogimi Village 2 0 2377, THa1* Nuuha, Ogimi Village 7 7 3844-3850 Miyagi, Higashi Village 3 3 4173, 4431-4432 Mt. Gusukuyama, Ie 9 8 2353 (=NSMT-Mo 73924), 2354-2355, Village 2357-2359, 2362-2363 Higashimae, Ie Village 4 4 2364-2367 Kouri Island, Nakijin 10 5 2650, 2794-2799, 3705-3706, 3851-3852 Village Imadomari, Nakijin 1 1 2499 Village Mt. Yae 1 0 2812 Mt. Katsuu 0 5 2321, 2497, 2589-2590, 2600 Genka, Nago City 7 9 2503, 3707, 3829-3833, 3913, 3972 Yagaji Island, Nago City 1 2 2378, 2614 Goga, Nago City 1 1 2346 Nagogusuku, Nago City 2 3 2602, 3613-3614 Sedake, Nago City 1 1 2368 Manzamo, Onna Village 10 5 1999-2002, 2345, 2896 (=NSMT-Mo 73925), MNZ-kw1-3*, MNZ-hs1-3** Ikei Island, Uruma City 4 1 2805-2806, 2822, 2855 Miyagi Island, Uruma 3 1 2809-2810, 3803 City Henza Island, Uruma 8 1 2815-2821, 2854 City Ishikawa-Yamashiro, 2 2 2894, 3854 Uruma City Ihagusuku, Uruma City 0 1 2655 Agenagusuku, Uruma 1 0 2800 City Henna Shell Mound, 5 5 2852 (=NSMT-Mo 73960), 2853, 3857-3859 Uruma City Katsurengusuku, Uruma 1 0 2813 City Chibanagusuku, Okinawa 2 2 3855-3856 City Systematic Revision of the Subgenus Luchuhadra 143

Appendix (continued). Sampling information of specimens used in this study. Sample size Species Locality Voucher specimens Shell Genitalia Kishaba, Kitanakagusuku 6 7 2892-2893, 3798-3802 Village Futenma Shrine, 1 0 2804 Ginowan City Urasoe Cemetery, Urasoe 5 5 2396, 2483, 3675-3677 City S. e. eucosmia Hedo, Kunigami Village 10 7 2352, 3960-3962, 3974-3976, HDa-kw1-3* Mt. Hedo-Ishiyama 3 5 2236, 2004-2006, 3837 Kayauchi-Banta, 6 6 2348, 3804-3807, 3957 Kunigami Village Oku, Kunigami Village 0 1 2605 Benoki, Kunigami 2 4 3632, 3693, 3702, 3810 Village Yona, Kunigami Village 3 3 2615, 3699, YN1* Iji, Kunigami Village 4 7 3820, 3965-3966, 3977, 3978-3980 Hiji, Kunigami Village 6 7 2858-2862, HJI1*, HJI3* Tsuha, Ogimi Village 1 5 2609, 2611, 3910, 3983-3985 Kuruma, Higashi Village 2 2 4172, 4175 Genka, Nago City 2 6 2648-2649, 3911, 3971, 3973, 3951 Futami, Nago City 1 2 2579, FTM1* Sukuta, Nago City 2 3 3914-3915, 4002 Henoko, Nago City 1 1 4177 Kanna, Ginoza Village 9 9 2654, 2801, 3618, 3708, 3770, 3967-3970, 3916 Hamahiga Island, Uruma 4 6 4178-4183, HMH1-4** City Shimabukuro, 1 0 2823 Kitanakagusuku Village Toguchi, Kitanakagusuku 9 9 2881, 2885-2887, 3792, 3794-3797 Village Nakagusuku, 6 8 2384-2385, 2387-2390, 2878, 3769 Nakagusuku Village Sueyoshi, Naha City 4 6 2484, 2486, 3730-3733 Koganemori, Naha City 1 0 2814 Sefautaki, Chinen Village 2 2 2003, 2080 Hyakuna, Tamagusuku 14 4 2793, 2829-2830, 3863, 4005, HYN1-10** Village S. e. erabuensis Uchijiro, Wadomari Town 13 9 2418, 2473 (=NSMT-Mo 73931), 2474(= NSMT-Mo 73932), 2475-2476, 3720-3723, erb- kw1-4* S. iheyaensis Mt. Gayozan, Iheya 4 2 3674, 3674b, 3768 (=NSMT-Mo 73940), No. Island 1483*** S. amanoi Hyakuna, Tamagusuku 10 10 1997, 2825 (=NSMT-Mo 73939), 2826, Village 3860-3862, 3949, 3950, 4003, 4004 Yaese Park, Kochinda 2 0 4478-4479 Town S. omoro Hiyajo, Kume Island 9 1 4449, omr-kw1-4*, oHS1-5** Uezuke, Kume Island 1 1 2905 144 Y. Kameda & M. Kato

Appendix (continued). Sampling information of specimens used in this study. Sample size Species Locality Voucher specimens Shell Genitalia Kanegusuku, Kume 6 6 3776 (=NSMT-Mo 73941), 3777 (=NSMT-Mo Island 73942), 3778-3781 Aka, Kume Island 1 1 3785 Mt. Ara, Kume Island 1 1 4248 S. hemihelvus Mt. Nobaru, Miyako 7 7 2335 (=NSMT-Mo 73933), 2336-2340, 2847 Island (=NSMT-Mo 73934) Tropical Botanical 0 1 3586 Garden of Miyakojima City * Kept in A. Kawakita’s collection; ** kept in M. Hoso’s collection; *** Hirase Collection in Kyoto University Museum. Numbers without asterisks represent specimen IDs in the first author’s collection (Kameda Collection) Systematic Revision of the Subgenus Luchuhadra 145

沖永良部島以南に分布するオキナワヤマタカマイマイ類 （有肺類：ナンバンマイマイ科：ニッポンマイマイ属）の再検討と再記載

亀田勇一・加藤 真

要 約

オキナワヤマタカマイマイ亜属（ナンバンマイマイ科）は琉球列島に固有の樹上性の陸貝である。筆 者らは以前の研究においてオキナワヤマタカマイマイが以下の 2 つの生物学的種からなり，沖永良部島 の固有種，オキノエラブヤマタカマイマイとヒメユリヤマタカマイマイもこの中に含まれることを示し た。これを受けて本稿ではこの種群の再記載を行った。また，遺伝的にも独立種であると確認されたイ ヘヤヤマタカマイマイ，アマノヤマタカマイマイ，オモロヤマタカマイマイ，ウラキヤマタカマイマイ の 4 種についても生殖器形態を再評価し詳述した。

Satsuma（ Luchuhadra） largillierti（ Pfeiffer, 1849） シラユキヤマタカマイマイ（新称） 殻は本亜属にあってはやや低平で，殻高は殻径より小さい。ほとんどの個体は白色無帯あるいは周縁 に 1 本の色帯を持つ。生殖器では膣や陰茎付属肢はあまり肥厚せず，陰茎本体は陰茎鞘の半分から 3 分 の 2 程度の長さであること，鞭状器が短く急に細まること，輸精卵管が受精嚢柄部の周りを螺旋状に 1 回転する個体が多いことなどが特徴である。従来沖縄島南部の個体群がこの学名で呼ばれていたが，そ れは次種に相当する。本種の分布域は沖縄島の浦添市以北と沖永良部島であり，那覇市以南には生息し ない。なお沖永良部島の個体群はヒメユリヤマタカマイマイ S. sooi Minato, 1982 と呼ばれてきたが，沖 縄島産の本種と遺伝的・形態的に明確な差が見られないため同種となる。

Satsuma（ Luchuhadra） eucosmia eucosmia（ Pilsbry, 1895） オキナワヤマタカマイマイ 殻は前種よりやや大きく，比較的背が高い。色彩は赤地に 1 本の白帯を周縁に持つもの，白地に 2 本 の色帯を周縁に持つもの，白色無帯の 3 つが基本的なパターンである。生殖器では膣と陰茎付属肢の基 部が著しく肥厚すること，陰茎本体が陰茎鞘の 4 分の 3 以上の長さであること，鞭状器がやや長く徐々 に細くなることなどで前種と区別できる。沖縄島南部と北部に分布し，南部ではアマノヤマタカマイマ イと，北部では前種と同所的に生息することがある。これまでに“オキナワヤマタカマイマイ Satsuma largillierti（ あるいは Luchuhadra largillierti）”として図鑑等で紹介されていたものの多くは本種である。 学名を伴わない場合でも本種の個体をオキナワヤマタカマイマイとして取り上げている例が多いことか ら，混乱を避けるため本種の和名をオキナワヤマタカマイマイとする。 なおオキノエラブヤマタカマイマイは従来独立種とされてきたが，遺伝的には本種に含まれるうえ， 殻形態以外では明確に区別できないため亜種（S. eucosmia erabuensis）とする。