A new subspecies of the Asian mantis Hierodula patellifera (Audinet-Serville, 1839), Hierodula patellifera daitoana ssp. nov., is described based on specimens collected from the Daito Islands, the Ryukyus, Japan. This new subspecies is distinguished from the nominotypical subspecies H. patellifera patellifera in adulthood by the relatively larger body size, the larger number of antennal segments, the presence of a white marking along the dorsal-inner surface on the procoxa, and marginal spines of the procoxa comprising two large and several small tooth-like projections.

Dictyoptera, Kita-daito-jima Island, Minami-daito-jima Island, nymph, Okinawa, taxonomy

The mantis species Hierodula patellifera (Audinet-Serville, 1839) (Mantodea: Mantidae) is widely distributed in the Oriental and eastern Palearctic regions, including India, Nepal, China, Taiwan, Korea, Japan, Vietnam, Thailand, Malaysia, Singapore, New Guinea, Java, Sumba, the Philippines, Italy, France, and Hawaii (Fig. 1; Ehrmann 2002, Leong 2009, Ehrmann and Borer 2015, Patel and Singh 2016, Mukherjee et al. 2017, Battiston et al. 2019, Moulin 2020). In Japan, it is distributed in Honshu, Shikoku, Kyushu, and the Ryukyus (Nakamine 2016, Oshima et al. 2020). It is readily distinguished from other members of the genus by the marginal spines of the procoxa, which are two to five in number, white or yellow, well defined, and tear drop shaped (Leong 2009, Zhu et al. 2012, Chatterjee and Srinivasan 2013, Majumder et al. 2015, Shcherbakov and Anisyutkin 2018). In this species, a single subspecies, H. patellifera manillana Giglio-Tos, 1912, was formerly recognized as part of the Philippine population by Giglio-Tos (1912) and Beier (1935), although no justification for this designation was provided. However, this subspecies has been considered a synonym of H. patellifera by Ehrmann (2002) and subsequent authors (Nakamine 2016, Otte et al. 2020). At present, H. patellifera has no infraspecific taxa.

Fig. 1. 

Total known distribution of Hierodula patellifera in Asia.

The Daito Islands consist of five oceanic islands located in the Philippine Sea southeast of the main island of Okinawa, Japan. Among these islands, those of Kita-daito-jima and Minami-daito-jima, which are populated by humans, lie approximately 360 km from the nearest neighboring island, Okinawa-jima, and provide a unique isolated ecosystem populated by several endemic species (Shimizu 2003).

During an investigation of the mantis fauna of the Daito Islands between 2015 and 2018, I collected several individuals of an indeterminate Hierodula species from both Kita-daito-jima Island and Minami-daito-jima Island. Detailed observations of the male genitalia indicated that these individuals were clearly specimens of H. patellifera (Fig. 2); however, other morphological characters, including the relative length of the body, number of antennal segments, coloration of the procoxae, and shape of the marginal spines, were distinctly different from those of other populations of the species. Eventually, I considered the possibility that the Daito Islands population is a distinct subspecies.

Fig. 2. 

Disarticulated genital complex (to isolate the individual phallomeres) of Hierodula patellifera, male, dorsal view: A–C. Hierodula patellifera patellifera from Okinawa-jima Is.; D–F. Hierodula patellifera daitoana ssp. nov., from Kita-daito-jima Is. (holotype); A, D. Left phallomere; B, E. Ventral phallomere; C, F. Right phallomere. Scale bar: 1 mm.

In the present paper, I describe this putative subspecies of H. patellifera from the Daito Islands, for which the name Hierodula patellifera daitoana ssp. nov. is proposed.

Hierodula patellifera daitoana ssp. nov. was occasionally collected by K. Oshima between 2015 and 2018. Day and night surveys involving opportunistic collections were conducted on Minami-daito-jima Island from February 17 to 20, 2015 and May 14 to 17, 2016, and on Kita-daito-jima Island from September 24 to 26, 2016 and June 24 to 28, 2018. Individuals that were nymphs at the time of collection were reared to adulthood and then dried for morphological observations. The specimens were examined under a stereoscopic microscope (SZ60; Olympus, Tokyo, Japan), and photographs were taken using a digital camera (EOS8000D; Canon, Tokyo, Japan). Measurements of body length (from the anterior margin of the pronotum to the apex of the wing) were taken using a ruler. Observations and photographs were based on both fresh and dried specimens. The type specimens have been deposited in the Laboratory of Entomology, Tokyo University of Agriculture, Atsugi, Japan (LETUA).

I express my cordial thanks to Kazuhisa Yamasaki (the University of Tokyo) for his constructive suggestions. I would also like to thank Yoshinobu Kusumoto (Western Region Agricultural Research Center, NARO) and Koichi Tanaka (Tokyo University of Agriculture) for assistance regarding the identification of plant species, the members of our laboratory for kindly offering materials and supporting my field investigations, and Tadashi Ishikawa (Tokyo University of Agriculture) for his critical reading of the manuscript and valuable comments.