Philhygra pseudomagniceps Klimaszewski and Chandler, 2023

Klimaszewski, Jan, Chandler, Donald S., Davies, Anthony & Bourdon, Caroline, 2023, Aleocharine rove beetles of New Hampshire, USA: new taxa and new records (Coleoptera, Staphylinidae, Aleocharinae), Zootaxa 5364 (1), pp. 1-141 : 64

118. Philhygra pseudomagniceps Klimaszewski and Chandler sp. n.

Figs. 8a–g , Table 1

Holotype (male). USA, New Hampshire, Rockingham Co., Jct. 1A & 1B, near Foyes Corner , 12.V.1982, D.S. Chandler, sift oak and beech litter ( CNC) . Paratypes: USA: New Hampshire, Grafton Co.: Bedell Bridge S. P. @ Oliverian Brook , 7–24.V.1992, 25.V–7.VI.1992, D.S. Chandler, FITrap, 2 males ; 26.VIII.1982, berlese old river drift, D.S. Chandler, 1 male. Rockingham Co.: Seabrook backdunes, 18–31.V.1989, D.S. Chandler, FIT, 1 male . Canada: Quebec, St-Joseph-du-Lac, 11.VII.2016, T. Struyve, car netting ( CNC) 4 males, 1female , 1 sex? New Brunswick, Queens Co.: Canning Grand Lake near Scotchtown , 45.8762N, 66.1816W, 25.V.2006, R.P. Webster, oak and maple forest near lake shore in litter near vernal pool ( RWC) 3 females . Sunbury Co.: Maugerville Portobello Creek N.W.A., 45.8992N, 66.4248W, 27.V.2004, R.P. Webster, silver maple forest, margin of vernal pond in moist leaf litter ( RWC) 2 males . Restigouche Co.: Little Tobique R. near Red Bk. , 47.4465N, 67.0698W, 13.VI.2006, R.P. Webster, alder swamp near river in debris on muddy soil near brook ( RWC) 1 female . York Co. Douglas Keswick River at Rt. 105, 45.9922N, 66.8326W, R.P. Webster, river margin on moist clay ( RWC) 1 male .

Etymology. This specific name pseudomagniceps is derived from the name of the Palearctic species Philhygra hygrobia (Thomson) (= P. magniceps (J. Sahlberg)) , with the addition of the prefix “pseudo,” in an allusion to the similarity between these two species.

Diagnosis. Distinguishable by the subparallel body, subquadrate pronotum, elytra at suture slightly longer than pronotum along midline, integument light brown to dark brown with paler pronotum, elytra, apex of abdomen, legs and basal antennomere ( Fig. 8a ); in lateral view subapical part of tubus of median lobe of aedeagus narrow, slightly produced ventrad and with apical part ovoid in shape ( Fig. 8b ).

Description. Body length 2.5–2.8 mm, moderately convex, moderately glossy, narrowly subparallel; head, pronotum and base of abdomen about the same width, elytra distinctly wider; integument light to dark brown with paler pronotum, elytra, apex of abdomen, legs and basal antennomere ( Fig. 8a ); forebody moderately densely pubescent, pubescence of pronotum directed laterad from midline and on elytra latero-posteriad, punctation fine, microsculpture not apparent at low? magnification; head round posteriad, eyes as long as posterior region of head, slightly expanded outside contour of head (fig. 8a); antennomeres I–VI elongate, VII–X subquadrate; pronotum subquadrate; elytra with scarcely visible postero-lateral emargination; abdomen slightly widening to mid-length, sides broadly arcuate. Male. Tergite VIII transverse, apical margin arcuate ( Fig. 8c ); sternite VIII strongly elongate, parabolic apically, antecostal suture distal to base of sternite ( Fig. 8d ); median lobe of aedeagus in lateral view with broadly elongate bulbus and small and narrow crista apicalis; tubus narrowly elongate, slightly produced ventrad and apical part ovoid in shape, sclerites of internal sac elongate, sharply pointed apically ( Fig. 8b ). Female. Tergite VIII transverse, apical margin arcuate ( Fig. 8e ); sternite VIII slightly subquadrate and rounded apically ( Fig. 8f ); pygidium approximately rectangular, structure membranous and irregularly shaped ( Fig. 8g ).

Distribution. Known only from Rockingham and Grafton Counties in New Hampshire, USA; and from New Brunswick and Quebec in Canada.

Collection and Habitat data. The NH specimens were captured primarily by FITs placed in different forest types, but single specimens were also taken from oak and beech litter, and old river drift. All specimens from Quebec were captured by car netting. Specimens from New Brunswick were found in an oak and maple forest near a lake shore in litter near a vernal pool; in moist leaf litter at margin of vernal pond in silver maple forest; in alder swamp near river in debris on muddy soil near brook; and at river margin on moist clay.

Comments. We have compared external features and the shape of the median lobe of the aedeagus of P. pseudomagniceps with the north-eastern Nearctic Philygra species and Palearctic species. The shape of median lobe of aedeagus of P. pseudomagniceps is unique among the Nearctic species and there are no similar species known to us. However, the median lobe of our species is similar in general shape to that of Palearctic P. hygrobia (Thomson) , except for the ovoid expansion of the apex of the median lobe and differently shaped structures of the internal sac in P. pseudomagniceps . For illustrations of the median lobe of aedeagus of the latter species see Palm (1970) and Brundin (1944).

Figures

FIGURE 8a–g. Philhygra pseudomagniceps Klimaszewski and Chandler sp. n.: (a) habitus in dorsal view; (b) median lobe of aedeagus in lateral view; (c) male tergite VIII; (d) male sternite VIII; (e) female tergite VIII; (f) female sternite VIII; (g) pygidium. Scale bar for habitus = 1mm; remaining scale bars = 0.2mm.