Eimeria hilleri, Tokiwa & Chou & Kitazoe & Ito & Torimoto & Shoshi & Sanjoba & Yamamoto & Yoshimura, 2022

Tokiwa, Toshihiro, Chou, Shyun, Kitazoe, Hina, Ito, Keiko, Torimoto, Ryouta, Shoshi, Yuki, Sanjoba, Chizu, Yamamoto, Masami & Yoshimura, Hisashi, 2022, Three new species of Eimeria (Apicomplexa: Eimeriidae) from the Amami rabbit, Pentalagus furnessi (Mammalia: Leporidae), International Journal for Parasitology: Parasites and Wildlife 18, pp. 194-200 : 198

3.3. Eimeria hilleri n. sp. ( Figs. 4 and 6b )

3.3.1. Description

Oocyst shape: ellipsoidal; number of walls: 2; wall thickness: 2.0 (1.5–2.5); wall characteristics: outer is rough, yellowish-brown, and easily detached, inner is smooth and light yellow; L × W: 34.7 × 21.4 (30.6–41.2 × 15.2–24.3); L/W ratio: 1.6 (1.5–2.0); M: present; M characteristics: in the outer layer of the wall, 3.9 (3.3–5.1) wide; OR and PG: both absent.

Sporocyst shape: elongate-fusiform to elongate-ovoidal; L x W: 15.7 × 8.3 (14.5–17.3); L/W ratio: 1.9 (1.7–2.1); SB: present; SB characteristics: nipple-like; SSB: present; SSB characteristics: narrow and rounded; PSB: absent; SR: present; SR characteristics: a compact mass of large granules or a few scattered granules between SZ; SZ: elongated with one end wider than the other, lying length-wide head-to-tail, and with a clear RB posterior to N.

3.3.2. Taxonomic summary

Type host: Mammalia ( Lagomorpha : Leporidae ), P. furnessi (Stone, 1900) , Amami rabbit.

Other hosts: None to date.

Type locality: Amami-Oshima and Tokunoshima Islands, Kagoshima, Japan .

Site of infection: Unknown. Samples were obtained from feces.

Sporulation: Exogenous. The exact hours were unknown, but oocysts became fully sporulated within 5 days at 23–26 ◦ C.

Prevalence: 25.0% (9/36, 95% CI 13.6–41.3%) of the type host.

Prepatent and patent periods: Unknown.

Materials deposited: Photosyntype of sporulated oocysts was deposited in the Meguro Parasitological Museum, Meguro, Tokyo, Japan, under MPM Coll. No. 21858.

ZooBank LSID: The ZooBank LSID is 9038A261-915C-4D4C-BF9F-7160D8A6FE40.

Etymology: Specific epithet “ hilleri ” is adopted from the name of Dr. Hiram Milliken Hiller (1867–1921), one of the discoverers of the Amami rabbit; it is given as a noun in the genitive case, in accordance to the Article 31.1. of the ICZN.

Remarks: Sporulated oocysts of E. hilleri resemble, in shape, the size, and the presence of two walls and micropyle, of Eimeria gobiensis [38.6 × 24.2 (27–49 × 19–32)] ( Gardner et al., 2009), Eimeria pierrecouderti [35 × 24 (33–37 × 23–26] ( Aoutil et al., 2005), Eimeria vejdovskyi [32.9 × 19.2 (30–37 × 18–21)] ( Pakandl, 1988), and Eimeria stiedai [37 × 20 (31–42 × 17–25)] ( Duszynski and Couch, 2013) detected from lagomorphs outside the Pentalagus genus. Oocysts of the first three species have a distinct OR, which those of E. hilleri lack, whereas E. stiedai oocysts have a few small OR, thin outer layer, and its sporocysts [18 × 10 (17–18 × 8–10)] ( Duszynski and Couch, 2013) are larger than those of E. hilleri .

Figures

Fig. 4. Nomarski interference contrast photographs of oocysts of Eimeria hilleri from the Amami rabbit stored in a potassium dichromate solution. M: micropyle; N: nucleus; OWo: outer layer of the wall; OWi: inner layer of the wall; RB: refractile body; SB: Stieda body; SR: sporocyst residuum; SSB: substieda body. Scale bars (all in the same scale) = 10 μm.

Fig. 6. Line drawings of the Eimeria species detected in the Amami rabbit. (a) Eimeria furnessi. (b) Eimeria hilleri. (c) Eimeria sagentae. Scale bar = 10 μ