フトミミズ科 ＞ アズマフトミミズ属 ＞ タニマミミズ Amynthas bigibberosus (Ishizuka, 1999)
Pheretima bigibberosa Ishizuka, 1999b: 40; Nakamura, 1999: 58.
タイプ産地：Mt. Mitake（東京都青梅市御岳山）
タイプ標本所在地：ホロタイプ 国立科学博物館（NSMT-An 245）
パラタイプ 国立科学博物館（NSMT-An 246）
＜外部形態＞
全長 55–73 mm、体幅 3.0–3.8 mm、体節数 70–86。
体色は、背面は赤褐色で、腹面は灰白色。第一背孔は第 12/13 体節間溝だが、まれに第 11/12 体節間溝に開口する。剛毛数は第 7 体節で 42–52 本、第 20 体節で 46–48 本。
受精嚢孔は 2 対で、口唇状に見え、第 6/7/8 体節間溝。受精嚢孔間距離は体周の約 1/2。環帯は第 14–16 体節を占める。雌性孔は第 14 体節の腹面中央に開口する。性徴が第 18
体節にあり、剛毛線を挟んで雄性孔に接しており、雄性孔と形や大きさは似ており、体表から突き出している。雄性孔は剛毛線より前に、性徴は剛毛線より後ろにある。雄性孔間距離は体周の約 1/3。
＜内部形態＞
隔膜は第 5/6/7/8 体節間でやや厚く、第 8/9/10 体節間で欠き、第 10/11/12/13/14 体節でやや薄い。
腸は第 15 体節から始まる。腸盲嚢は指状型で、4–6 本の小嚢に別れ、第 27 体節に開口し、前方に3–4体節分伸びる。
受精嚢は 2 対で、第 7–8 体節にあり、主嚢はシャベル型で、太い導管を持つ。副嚢の末端はソーセージ型に膨れ、太い導管を持つ。受精嚢の基部は強い膜で覆われ、体壁に強く固定されている。貯精嚢は大きく、第 10–15 体節まで広がる。摂護腺は大きく、第 17–22
体節まで広がる。生殖腺は第 18 体節にあり、瓶状複生殖腺で、複数の嚢状部を持つ。
Description. Body. Length 55–73 mm, width 3.0–3.8 mm. Number of segments 70–86. Reddish brown dorsally, greyish white ventrally.
External characters. Two pairs of spermathecal pores large, torn sideways, situated in furrows 6/7/8, in ventro-lateral sides, separated by a distance of ca. 1/2 body
circumference. Genital markings large, projecting from the surface, paired, on segment XVIII, situated close to male pore and similar in shape and size to the latter. Male pore projecting
from the surface, sucker type, on segment XVIII. Male pores and genital markings quite similar in shape and thse two arranged side by side with a setal line between them. Male pores and
genital markings not distinguishable in external from each other. Male pores situated at presetal line (in front of the setal line), separated by a distance of ca. 1/3 body circumference.
Female pore single, mid-ventrally on segment XIV. First dorsal pore beginning in furrow 12/13 rarely in 11/12. Clitellum including segment XIV–XVI. Setal number 42–52 in segments VII, 46–48
in segment XX.
Internal characters. Manicate intestinal caeca each with 4–6 diverticula, originating in segment XXVII, extending anteriorly for 3–4 segments. Intestine begins in XV. Genital
glands consisting of complex duct bearing several capsulogenous glands on segment XVIII, with stalked glands associated with genital sucker. One genital sucker with several pieces of large
capsulogenous glands fixed to body wall. Septa absent in 8/9/10, slightly thickened in 5/6/7/8 delicate in 10/11/12/13/14. Two pairs of spermathecae large, on segments VII–VIII. Ampulla
consisting of a shovel-shaped pouch and its duct stout. Diverticulum consisting of a stout duct and a distal sausage like swelling. The basis of spermathecae duct covered with strong membrane
and firmly fixed to body wall. Seminal vesicle large and well developed, extending on segments X–XV. Prostata large, extending on segments XVII–XXII, corresponding to male pore.
Material examined. Holotype (NSMT-An 245) and 5 paratypes (NSMT-An 246): From litter and surface soil under a mixed forest of evergreen and deciduous trees, Mt. Mitake,
29–VII–1980, K. Ishizuka. Other specimens examined: 6 exs. with same data as type series.
Remarks. The new species resembles Pheretima heterogens Chen et Hsü, 1975, but is distinguishable from the latter species by (1) two pairs of spermathecal pores and
(2) the manicate intestinal caeca. The position of male pore at presetal line can-not be seen in all the other congeneric species of the genus Pheretima.
Blakemore（2003, 2010a, 2012b）は、疑問符付きでシマチビミミズとともにコヒダミミズのシノニムにしている。
Blakemore RJ, 2003. Japanese earthworms (Annelida: Oligochaeta): A review and checklist of species. Organisms Diversity and Evolution 11: 1-43.
Blakemore RJ, 2010a. Saga of Herr Hilgendorf's worms... In: Pavlíček T, Cardet P, Coşkun Y, Csuzdi C, (eds.), Advances in Earthworm Taxonomy IV (Annelida: Oligochaeta). Proceedings of the 4th International Oligochaeta Taxonomy Meeting Diyarbakir, 20-24 April, 2009.
Zoology in the Middle East Supplementum 2. Kasparek Verlag, Heidelberg. pp. 7-22.
Blakemore, R.J., 2012b. Japanese earthworms revisited a decade on. Zoology in the Middle
East 58 suppl 4: 15-22.
Ishizuka, K., 1999b. New species of the
genus Pheretima s. lat. (Annelida, Oligochaeta, Megascolecidae) from Tokyo, Japan- species with manicate intestinal
caeca. Bulletin of the National Science Museum (Japan). Series A. Zoology 25(1): 33-57.
石塚小太郎, 2001. 日本産フトミミズ属
(Genus Pheretima s. lat.) の分類学的研究. 成蹊大学一般研究報告 33(3): 1-125.
Nakamura Y, 1999. Checklist of earthworms of Pheretima genus group (Megascolecidae: Oligochaeta) of the world. Edaphologia 64: 1-78.
日本産ミミズ大図鑑