Ixodes (Australixodes), Barker & Kelava & Heath & Seeman & Apanaskevich & Mans & Shao & Gofton & Teo & Byrne & Ito & Tan & Barker & Nakao, 2023

Barker, Stephen C., Kelava, Samuael, Heath, Allen C. G., Seeman, Owen D., Apanaskevich, Dmitry A., Mans, Ben J., Shao, Renfu, Gofton, Alexander W., Teo, Ernest J. M., Byrne, Andrew F., Ito, Takuya, Tan, Craig J., Barker, Dayana & Nakao, Ryo, 2023, A new subgenus, Australixodes n. subgen. (Acari: Ixodidae), for the kiwi tick, Ixodes anatis Chilton, 1904, and validation of the subgenus Coxixodes Schulze, 1941 with a phylogeny of 16 of the 22 subgenera of Ixodes Latreille, 1795 from entire mitochondrial genome sequences, Zootaxa 5325 (4), pp. 529-540 : 533-536

Subgenus Australixodes n. subgen. Barker, S.C. & Barker, D.

urn:lsid:zoobank.org:act:ADD7AD7C-1317-4FE4-87C7-D70D08847456

Type species: Ixodes anatis Chilton, 1904 , here designated.

Subgeneric combination: Ixodes (Australixodes) anatis Chilton, 1904 .

Type depository: The record of Kwak & Heath (2018) about the syntype are correct: Canterbury Museum , New Zealand ( CMNZ, Reference number: 2015.162.1) (A.C.G. Heath) .

Species included: monotypic, Ixodes anatis Chilton, 1904 .

Diagnosis: With characteristics of its sole constituent species Ixodes (Australixodes) anatis . Kwak & Heath (2018) provided detailed diagnoses and illustrations of the larvae, nymphs, males and females; these will not be repeated here. Ixodes (Australixodes) anatis is the only tick that is known from the kiwi ( New Zealand); this information, together with the combination of morphological features noted by Kwak & Heath (2018), make I. (Australixodes) anatis readily distinguishable from all other ticks. Ixodes anatis has been recorded from three taxa of kiwi in New Zealand: Apteryx mantelli Bartlett, 1852 (North Island kiwi), A. australis australis Shaw, 1813 (South Island brown kiwi) and A. a. lawryi Rothschild, 1891 (Stewart Island brown kiwi) (Heath 2010).

Etymology: The name of this new subgenus refers to the geographic distribution of I. (Australixodes) anatis in New Zealand in Australasia (masculine).

Distribution: New Zealand.

Remarks: Guglielmone et al. (2020) gives a list of the descriptions and redescriptions of the sole species in this subgenus, I. (Australixodes) anatis . Other papers pertinent to the geographic distribution and biology of I. (Australixodes) anatis: Heath (2010 a, 2010b ) and Heath et al. (2011), Swift et al. (2015), Bansal et al. (2021).

Discussion: A subgenus is needed for I. anatis for two reasons. First, I. anatis does not fit, morphologically, into the subgenus Sternalixodes ( Heath 1977; Kwak et al. 2017; Kwak & Heath 2018). The differences are discussed in detail by Kwak & Heath (2018) but here we reiterate that none of the life stages of I. anatis has a sternal plate, the eponymous character state that has been used to define the subgenus. Second, genetically, I. anatis does not fit into the subgenus Sternalixodes either (Fig. 2). Rather, our mt genome phylogeny revealed that the sister group of I. anatis is Ceratixodes + Sternalixodes (Fig. 2). Camicas et al. (1998) placed I. anatis in the I. unicavatus species group of the subgenus Scaphixodes but did not explain their reasons. The other three species in the I. unicavatus species group of Camicas et al. (1998) were I. unicavatus Neumann, 1908 from the Palaearctic, I. signatus (Birula, 1895) from Palaearctic and Nearctic, and I. downsi (Kohls, 1957) from the Neotropical region.