Adalmus serrilumbus Byeon & Chandler, 2024

Byeon, Ui-Joung, Chandler, Donald S., Leschen, Richard A. B. & Park, Jong-Seok, 2024, Revision of the New Zealand genus Adalmus with description of six new species (Coleoptera: Staphylinidae: Pselaphinae), Acta Entomologica Musei Nationalis Pragae 64 (1), pp. 17-32 : 27-28

Adalmus serrilumbus Byeon & Chandler , sp. nov.

( Figs 8 , 10 )

Type material. HOLOTYPE: J (slide mounted, NZAC): “ NEW ZEALAND: WD 1.8km n Punakaiki , 80m 19.xii.1984 - 20.i.1985 hdwd. for. with nikau A.Newton / M.Thayer 718 // flight intercept (window) trap // NZ Arthropod Collection Private Bag 92170 Auckland New Zealand NZAC04261145”.

Diagnosis. Male of this species can be distinguished from other Adalmus species by the following characters: body size longer than 2.2 mm; antennomere I approximately 2.8 times as long as II; rostrum narrow (HW: RW = 52: 20); protrochanter with small spine ( Fig. 8L ), mesotrochanter weakly convex ( Fig. 8M ), metatrochanter with distinct curved spine ( Fig. 8N ); left paramere thick, S-shaped, with thin, short, and curved spine, right paramere curved, apex bifurcated; apex of median lobe curved and serrate ( Figs 8O, P ).

Description. BL 2.40 mm (FBL 1.65 mm); body blackish- -brown, antenna, and legs reddish-brown, maxillary palpus and tarsi yellowish-brown; body pubescent.

Head slightly broader than long (HL: HW = 42: 52), widest at anterior 2/3, eyes convex, impression between ridge of antennal tubercles deep, ridge of antennal tubercles parallel; apex of rostrum weakly projecting, clypeus barely visible in dorsal view, temple as long as gena, gena nude in dorsal view; antennal length 0.97 mm, antennomere I approximately three times as long as II, antennomere II longer and broader than III–VIII, antennomeres III–V of similar length, VI and VIII of similar length, IX and X of similar length, antennomeres IX–XI forming indistinct club, XI approximately 1.7 times as long as broad.

Thorax. Prothorax slightly broader than head (HW: PW = 41: 44), subhexagonal (PL: PW = 47: 44), broadest at anterior 2/5, narrowest at base.

Elytra slightly broader than long (EL: EW = 65: 74), with sutural striae, weak impression at basal elytral foveae, subhumeral foveae present, not visible in dorsal view.

Legs. Protrochanter with small spine; profemur weakly rugose on ventral side; mesotrochanter weakly convex, metatrochanter with distinct curved spine; tibiae and femora of similar length, moderately long.

Aedeagus asymmetric, 0.37 mm long, with diaphragm and basal stem; parameres asymmetric, left paramere thick, S-shaped, with thin, short, and curved spine, right paramere curved, apex bifurcated; apex of median lobe curved and serrate.

Sexual dimorphism. Female unknown.

Etymology. The specific epithet is a noun in the nominative case, a combination of the Latin words serratus (ʻserrateʼ, masculine) and lumbus (ʻgenitaliaʼ, masculine), and refers to the serrate apex of the median lobe.

Distribution. New Zealand (South Island: WD; Fig. 10 ).

Figures

Fig. 8. Adalmus serrilumbus sp. nov. A – head; B – prosterum; C – meso- and metaventrite; D – elytra; E – abdominal ventrites; F – abdominal tergites; G – antennae; H – mandibles; I – labrum; J – labium; K – maxillae; L – front leg; N – middle leg; M – hind leg; O–P – aedeagus in ventral (O) and lateral (P) view.

Fig. 10. Collection localities in New Zealand.