Phormiobius matau, Shen & Choi & Leschen, 2020

Shen, Jia-Wei, Choi, Su-Ho & Leschen, Richard A. B., 2020, Revision of the New Zealand endemic genus Phormiobius (Coleoptera: Staphylinidae: Pselaphinae), Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 60 (2), pp. 553-564 : 561

Phormiobius matau sp. nov.

( Figs 6 , 10 )

Type material. Hඈඅඈඍඒඉൾ: J, point-mounted ( NZAC): ‘Shakespeare Bay, Picton // 11 Aug 1969, J.Mc. Burney // litter’. Pൺ*©ൺඍඒඉൾඌ(2 JJ, NZAC [1 in ethanol]): MB: Pelorus Bridge Scenic Reserve, Totara Walk, beech forest, 17m, 12/12/2007, K. Marske, J.Allwood, sifted beech litter and woody debris, S 41.17.927′, E 173.34.380′, KM 118.

Additional material examined. 11♀♀ (all NZAC): SD: 1♀, same data as holotype; 1 ♀ [in ethanol], Pelorus Bridge Scenic Reserve, Totara Walk, beech forest, 17m, 12/12/2007, K.Marske,J.Allwood, sifted beech litter and woody debris, S41.17.927′, E173.34.380′, KM 118; 3, Opouri Saddle, 16/03/2018, J. Nunn, in forest floor litter. MB: 4 ♀♀, Ronga Saddle, 316m, 04/02/2014, J. Nunn, sifted forest floor litter, S41°07.402’, E173°36.981’; 2 ♀♀ [in ethanol], Pine Valley, 06/12/2018, sifting moss on rocks, 41, 30.209S, 173 30.486E, R Leschen & V. Sykora, RL2068.

Description. Body ( Fig. 6A ) length 1.95–2.12 mm (J, 2.10–2.12 mm; ♀, 1.95–2.05 mm), about 2.70× as long as wide (BL/AW = 2.69–2.71). Head about 1.24× longer than wide (HL/HW = 1.22–1.25). Pronotum about as long as wide (PL/PW = 1.08–1.09). Elytra wider than long, about 0.52× as long as wide (EL/EW = 0.51–0.53) and about 0.70× as long as pronotum (EL/PL = 0.69–0.71). Abdomen about 1.39× longer than wide (AL/AW = 1.39–1.40).

Male. Eyes with 13–14 facets. Abdominal concavities ( Fig. 6B ) present on V2 and V3; C2 deep and polished with edge conspicuously demarcated with lateral rims, greatest width twice length of metatrochanter and slightly widened posteriorly; C3 shallow with sparse setae and lacking lateral rims, apical spines minute. Metatrochanter ( Fig. 6D ) spinate, apex of spine rounded and curved in lateral view; metatibia ( Fig. 6C ) with big apical spine. Tergite 5 ( Fig. 6E ) about 1.21× wider than long, broadly rounded; ventrite 5 ( Fig. 6F ) strongly emarginated at apex. Aedeagus ( Figs 6G–I ) with basal bulb elongate and oval in dorsal view; median lobe unilobate in lateral view with pointed apex and raised rim at apical one-third; bilobate in dorsal view and about as wide as basal bulb and convergent towards apex.

Female. Eyes with 13–14 facets.

Differential diagnosis. This species can be easily distinguished from its congeners by males having sharply demarcated concavities on V2 and the very shallow concavities on V3 with minute spines. Additional male characters that characterize this species are as follows: metatrochanter with hook-like round spine that is curved in lateral view and metatibia with a large apical spine.

Etymology. The generic name is a direct transliteration of Māori for matau meaning ‘hook’ with respect to the hook-like process on the metatrochanter; it is a noun in nominative singular, standing in apposition.

Distribution: South Island: SD, MB.

Figures

Fig. 6. Diagnostic characters of Phormiobius matau sp. nov. A – habitus; B – abdomen, in ventral view; C – metatibia; D – metatrochanter; E – T8; F – V8 and T9; G – aedeagus, in dorsal view; H – same, in lateral view; I – same, in ventral view. Scale bars: A–B = 0.5 mm, C–I = 0.1 mm.

Fig. 10. Geographic distribution of Phormiobius brouni sp. nov., P. graceae sp. nov., P. halli Broun, 1917, P. matau sp. nov., P. pseudhalli sp. nov. and P. ramsayi sp. nov.