Orobdella shimadae, Nakano, Takafumi, 2011

Nakano, Takafumi, 2011, Redescription of Orobdella ijimai (Hirudinida: Arhynchobdellida: Gastrostomobdellidae), and two new species of Orobdella from the Ryukyu Archipelago, Japan, Zootaxa 2998, pp. 1-15 : 10-11

publication ID

https://doi.org/ 10.5281/zenodo.207870

publication LSID

lsid:zoobank.org:pub:685D1726-8F19-4E78-A9C0-2344846E85E0

DOI

https://doi.org/10.5281/zenodo.5691607

persistent identifier

https://treatment.plazi.org/id/2F5902C0-581C-4F5B-BAA5-D1928685B48F

taxon LSID

lsid:zoobank.org:act:2F5902C0-581C-4F5B-BAA5-D1928685B48F

treatment provided by

Plazi

scientific name

Orobdella shimadae
status

sp. nov.

Orobdella shimadae sp. nov.

( Figs. 8 View FIGURE 8 , 9 View FIGURE 9 )

Diagnosis. In life, dorsal surface greenish yellow, ventral surface whitish yellow. Somite VII triannulate. Somite VIII quinquannulate. Somites IX–XXV complete sexannulate. Somite XXVI quinquannulate. Pharynx reaching to XVI. Gastropore absent. Gastroporal duct narrow, tubular, descending to XV a 2. Male gonopore in XI b 5 /c 11 or at anterior of XI c 11, close to b 5 /c 11. Female gonopore in XIII b 1 /b 2 or at anterior of XIII b 2, close to b 1 /b 2. Gonopores separated by nine annuli. Pre-atrial loop present, extending to ganglion XI. Atrial cornua absent.

Materials examined. Holotype. KUZ Z 128, mature specimen of 100.9 mm in body length, dissected, collected from in the soil along the Okuyona Forest Road (alt. 100 m, 26 °49.0´N, 128 °16.5´E), Kunigami, Okinawajima Island, Okinawa Pref., Japan, by Taku Shimada on April 9, 2010. Paratypes (a total of nine specimens collected from Okinawajima Island, Japan). Six specimens collected by Taku Shimada: KUZ Z 125 from Kunigami on February 15, 2010; KUZ Z 126, dissected, and KUZ Z 127, dissected, from Higashi on April 9, 2010; KUZ Z 130, dissected, from near the type locality on June 17, 2010; KUZ Z 137, and KUZ Z 138, dissected, from the Okuni Forest Road (26 °40.2´N, 128 °11.2´E), Higashi, on September 6, 2010; and KUZ Z 139 from the Okuyona Forest Road around the Benoki Dam (26 °47.0´N, 128 °16.3´E), Kunigami, on September 7, 2010. Two specimens collected from around the Benoki Dam, Kunigami on August 24, 2010: KUZ Z 131 (alt. 176 m, 26 ° 47´20 ˝ N, 128 ° 15´22 ˝ E), dissected, by Takafumi Nakano; KUZ Z 132 (alt. 191 m, 26 ° 47´22 ˝ N, 128 ° 15´21 ˝ E), by Keiko Tsubokawa.

Etymology. The specific name is a noun in the genitive case formed from the Latinized name of Mr. Taku Shimada who collected many valuable specimens of this species from Okinawajima Island.

Description of holotype. Body firm, muscular, BL 100.9 mm, BW 6.3 mm ( Fig. 8 View FIGURE 8 ). Caudal sucker ventral, oval, its diameter slightly smaller than maximum body width ( Fig. 9 View FIGURE 9 D). In life, dorsal surface greenish yellow, ventral surface whitish yellow, dorsal surface darker than ventral surface. In preservative, color faded, without any dark lines.

Somite I completely merged with prostomium ( Fig. 9 View FIGURE 9 A). Somite II uniannulate, not separated from I ( Fig. 9 View FIGURE 9 A). Somite III uniannulate ( Fig. 9 View FIGURE 9 A). Somite IV biannulate ( Fig. 9 View FIGURE 9 A). Somite V biannulate, a 3 forming posterior margin of oral sucker ( Fig. 9 View FIGURE 9 A, B). Somites VI triannulate ( Fig. 9 View FIGURE 9 A, B). Somite VII complete triannulate, a 1 = a 2 <a 3 ( Fig. 9 View FIGURE 9 A, B). Somite VIII complete quinquannulate, a 1> a 2 = b 5> c 11 = c 12 ( Fig. 9 View FIGURE 9 A, B). Somite IX complete sexannulate, b 1 <b 2 = a 2 = b 5> c 11 = c 12. Somites X–XXV complete sexannulate, b 1 <b 2 = a 2 = b 5> c 11 = c 12, or b 1 = b 2 <a 2 = b 5> c 11 = c 12 ( Fig. 9 View FIGURE 9 C–E), X b 5 the first annulus of the clitellum, XIII a 2 the last annulus of the clitellum. Somite XXVI sexannulate dorsally, b 1 = b 2 = a 2 <b 5> c 11 = c 12, quinquannulate ventrally, b 1 = b 2 = a 2 <b 5 <b 6, b 6 with slight furrow and the last complete annulus on the venter ( Fig. 9 View FIGURE 9 C, D). Somite XXVII incomplete triannulate ( Fig. 9 View FIGURE 9 C). Anus behind XXVII ( Fig. 9 View FIGURE 9 C). Post-anal annulus absent ( Fig. 9 View FIGURE 9 C).

Anterior ganglionic mass in VI a 2 and a 3. Ganglion VII in VII a 2. Ganglia VIII–XXIV in a 2 of each somite ( Fig. 9 View FIGURE 9 H). Ganglion XXV in XXV b 2; ganglion XXVI in XXVI b 1. Posterior ganglionic mass in XXVI a 2 –b 6.

Eyes three pairs, first pair dorsally in II, second and third pairs dorsolaterally on posterior margin of V (a 1 + a 2) ( Fig. 9 View FIGURE 9 A). Nephridiopores 17 pairs, ventrally at posterior margin of a 1 at VIII and b 2 of each somite, at IX– XXIV ( Fig. 9 View FIGURE 9 B, E). Papillae numerous, minute, hardly visible, one row on every annulus.

Pharynx agnathous, euthylaematous, reaching to XVI a 2 /b 5. Crop tubular, acecate, in XVI a 2 /b 5 to XXII b 2. Gastropore absent ( Fig. 9 View FIGURE 9 E, G). Gastroporal duct narrow, tubular but slightly bulbous at female gonopore, in XIII b 1 /b 2 to XV b 2, not joining with crop ( Fig. 9 View FIGURE 9 F). Intestine tubular, acecate, in XXII b 2 to XXV b 1. Rectum tubular, thin-walled.

Male gonopore at anterior of XI c 11, close to annular furrow of b 5 /c 11 ( Fig. 9 View FIGURE 9 E). Female gonopore at anterior of XIII b 2, close to annular furrow of b 1 /b 2 ( Fig. 9 View FIGURE 9 E, G). Gonopores separated by 9 annuli ( Fig. 9 View FIGURE 9 E). Testisacs multiple, two or three testisacs on each side in each annulus, in XVIII b 5 to XXV a 2. Epididymides absent. Ejaculatory bulbs absent. Ejaculatory ducts in XI a 2 to XVII c 11, coiled, widen from each junction with testisacs, narrow gradually toward each junction with atrium, with pre-atrial loop extending to ganglion XI ( Fig. 9 View FIGURE 9 H, I). Atrial cornua absent. Atrium rudimentary in XI b 5 and c 11 ( Fig. 9 View FIGURE 9 H, I). Ovisacs one pair, thin-walled, globular, in XIII a 2 and b 5 ( Fig. 9 View FIGURE 9 H, J). Oviduct thin-walled, right oviduct crossing ventrally beneath nerve cord, both oviducts converging into common oviduct in XIII b 2 ( Fig. 9 View FIGURE 9 H, J). Common oviduct thin-walled, very short, directly descending to female gonopore ( Fig. 9 View FIGURE 9 H, J).

Variation. Median black line on dorsal surface present or absent in preservative. Somite XXVI quinquannulate or sexannulate ( KUZ Z 139). Somite XXVII incomplete biannulate or triannulate; clitellum from X b 5 to XIII a 2. Pharynx reaching to XVI a 2 /b 5 –c 11 /c 12. crop reaching to XXII b 2 –XXII a 2 /b 5. Intestine reaching to XXIV b 5 / c 11 –XXIV c 12. Male gonopore in XI c 11 /c 12 or at anterior XI c 12, close to annular furrow of b 5 /c 11. Female gonopore in XIII b 1 /b 2 or at anterior of XIII b 2, close to annular furrow of b 1 /b 2. Testisacs in XVI c 11 –XVII a 2 /b 5 to XXIV a 2 –XXV b 2.

Distribution and ecology. Known from the mountain region of the northern part of Okinawajima Island in the Ryukyu Archipelago, Japan ( Fig. 1 View FIGURE 1 ). Leeches were found under rocks or fallen leaves.

Remarks. Orobdella shimadae is extremely similar to Orobdella dolichopharynx in Amamioshima Island. In Orobdella shimadae , however, its gastroporal duct is reaching only to XV b 2 (to XVI b 2 in O. dolichopharynx ). In accordance with the strict morphological uniqueness, Orobdella leeches from Okinawajima Island and Amamioshima Island is treated as the two distinct species, O. shimadae and O. dolichopharynx , respectively in this study.

KUZ

Zoological Collection of the Kyoto University