Nebria ( Falcinebria ) elephanta, Sasakawa, 2025

Sasakawa, Kôji, 2025, Taxonomic studies of the ground beetle subgenus Falcinebria Ledoux & Roux, 2005 (Coleoptera, Carabidae, Nebria) from the Japanese Alps (central Honshu), Shikoku, and Kyushu, Japan, ZooKeys 1254, pp. 131-148 : 131-148

Nebria ( Falcinebria) elephanta sp. nov.

Figs 3 , 13

Nebria reflexa : Uéno (1985): 56 (part; subgenus not specified).

Type materials.

Holotype: ♂ ( KS), Japan • Tokushima Prefecture, Tsurugi-cho, Ichiu, near Tsurugisan Ski Area , alt. 1000 m, 14-VII-2006, Masato Mori leg. Paratypes: 1 ♂ 1 ♀ ( KS), Japan • Tokushima Prefecture, Higashimiyoshi-cho, Nishisho, near Sajiki-tôge Pass , alt. 800 m, 10-VII-1999, Masato Mori leg.

Diagnosis.

Similar to the locally adjacent species N. chugokuensis Sasakawa, 2020 and N. uenoi Nakane, 1963 , but distinguished from N. chugokuensis by a smaller body size (in N. chugokuensis , 9.97–10.32 mm for males and 10.69–11.75 mm for females; Sasakawa 2020) and the absence of a concavity on the ventral surface of the aedeagal apex (present in N. chugokuensis ), and from N. uenoi by the shape of the endophallus, in particular, the developed gonopore protrusion (undeveloped in N. uenoi ) and the absence of lateroapical lobes on both sides (present in N. uenoi ).

Description.

Body length: ♂, 9.70–9.81 mm, 9.75 ± 0.08 mm ( n = 2); ♀, 10.54 mm ( n = 1). Sternum 7 with two setae on each ventrolateral side in the male, and three in the female. Other external structures, coloration, and chaetotaxy as in other related species that had been previously regarded as N. reflexa ( Sasakawa 2020) . Dorsobasal lobe large, semi-spherical. Dorsomedian lobe absent. Dorsoapical lobe scalene trapezium-shaped in dorsal view, with the left and right sides concave; the left side more concave than the right; the left apical corner more protruding than the right. Laterobasal lobes with the ventrobasal surface largely swollen in a semi-spherical shape; the other part less swollen but wide, reaching the base of the dorsobasal lobe. Ventrobasal swelling large, semi-ellipsoid. Lateroapical lobes absent on both right and left sides. Gonopore protrusion markedly large and long, with total length along the median line from the base of the protrusion to the gonopore (apical end of the protrusion) longer than that from the base of the endophallus (ostium of the aedeagus) to the base of the protrusion; basal half thick, oriented in the same direction as the median line of the endophallus; apical half slender, strongly bent right laterally. Relative sizes of some lobes and protrusions are as follows: ventrobasal swelling ≤ swelling of ventrobasal surface of laterobasal lobes ≈ dorsobasal lobe <dorsoapical lobe <basal half of gonopore protrusion.

Notes.

The description of setae on female sternum 7 as three pairs was based on only one specimen. This character state must be confirmed based on additional specimens, because in Carabidae , the number of setae on the body surface, including sternum 7, often varies due to additional setae, etc. The present collection sites are located on the northern slope of Mount Tsurugi-san in the eastern part of Shikoku. Considering the relatively wide distribution of related species and the continuity of the forest environment, which seems to be suitable for this group, N. elephanta is assumed to be widely distributed around Mount Tsurugi-san. In Shikoku, there is also a record of “ N. reflexa reflexa ” from Mount Takanawa-san in the western part, 110 km from Mount Tsurugi-san ( Yoshitomi et al. 2012). The identity of the Takanawa-san specimens remains to be clarified in a future study.

Etymology.

The specific name is derived from the Latin elephantus, - a, - um (elephant) and refers to the elongated gonopore protrusion of this species, which resembles the trunk of an elephant.

Figures

Figures 2–5. Habitus dorsal view of males of Nebria spp. 2. N. dracocephala sp. nov. holotype from Mount Ryûtô-san; 3. N. elephanta sp. nov. holotype from near Tsurugisan Ski Area; 4. N. hikosana holotype from Mount Hiko-san; 5. N. hikosana from Mount Seburi-san.

Figures 13–15. Right lateral (a), ventral (b), dorsal (c), left lateral (d), and posterodorsal (e) views of the endophallus of Nebria spp.; 13. N. elephanta sp. nov. holotype from near Tsurugisan Ski Area; 14. N. hikosana from Ryûmon-kyô Gorge; 15. N. hikosana from Mount Seburi-san.