Neoleptochelia japonica, Sato & Arakawa & Kakui, 2023

Sato, Akari, Arakawa, Kazuharu & Kakui, Keiichi, 2023, Two new species in Leptocheliidae (Crustacea: Peracarida: Tanaidacea) from Japan, with notes on their phylogenetic position and aspects of morphology, Zoologischer Anzeiger (Zool. Anz.) 306, pp. 51-68 : 65

4.4. Morphological comparison between N. japonica sp. nov. and N. javaensis

Females of N. japonica sp. nov. differ from those of N. javaensis in having the following character states (character state of N. javaensis in parentheses): antennal article 1 with a ventrodistal simple seta (without setae); antennal article 2 with outer simple seta (without seta); maxilliped-palp article 4 with outer seta (without seta); chelipedal carpus with seven dorsal simple setae (with eight); pleopodal protopod with inner plumose seta (without setae). Although details for most appendages were not available for N. javaensis , N. japonica sp. nov. males differ from those of N. javaensis in having the chelipedal carpus with seven dorsal and three ventral simple setae (with five or six dorsal and two ventral setae) and the fixed finger with five ventral simple setae (three ventral setae).

Our male individual of N. japonica sp. nov. has a seven-articulate antenna, whereas females have a six-articulate one. In Leptocheliidae , the seven-articulate condition has been reported in males in two species of Metaleptochelia (Metaleptocheliinae; Guţu, 2016), and in Alloleptochelia longimana ( Shiino, 1963) and Alloleptochelia evansi ( Edgar, 2012) ( Leptocheliinae ; Shiino, 1963, fig. 24F; Edgar, 2012, fig. 6-A2). In non-leptocheliid paratanaoideans, this condition is known only in males and females in Heterotanoididae ( Bird, 2012) . Observation of more males is needed to check whether the seven-articulate antenna is a stable male trait in Neoleptochelia , as Guţu (2011) did not indicate the number of male antennal articles in the type species N. javaensis , and we observed only one male for N. japonica sp. nov.