Proteinus sweeneyi Webster & Klimaszewski

Webster, Reginald P., Davies, Anthony E., Klimaszewski, Jan & Bourdon, Caroline, 2016, Further contributions to the staphylinid fauna of New Brunswick, Canada, and the USA, with descriptions of two new Proteinus species (Coleoptera, Staphylinidae), ZooKeys 573, pp. 31-83 : 42-44

Taxon classification Animalia Coleoptera Staphylinidae

Proteinus sweeneyi Webster & Klimaszewski sp. n. Figs 10-13

Holotype (male).

Canada, New Brunswick, Saint John Co., Dipper Harbour, 45.1169°N, 66.3771°W, 7.V.2006, R.P. Webster // Sea beach, in decaying sea wrack on gravel and sand // PHOTO 2015-007, C. Bourdon (CNC). Paratypes: Manitoba, 1 km north of Onanole, 29.VIII.1979, S.J. Miller, berlese ex mushrooms, aspen woods (2 ♂, CNC); Riding Mountain National Park, near refuse pit, 16.VIII.1979, S.J. Miller, berlese ex moose dung (1 ♀, CNC); same data except 15.VIII.1979, ex mammal burrows (2 ♂, CNC). New Brunswick, Madawaska Co., 47.5984°N, 68.3667°W, 16.X.2013, R.P. Webster // Mature hardwood forest, in decaying Tricholoma sp. (1 ♀, RWC). Queens Co., Cranberry Lake P.N.A., 45.1125°N, 65.6075°W, 24.IV-5.V.2009, R. Webster & M.-A. Giguère // red oak forest, Lindgren funnel trap (1 ♂, RWC). Restigouche Co., Jacquet River Gorge P.N.A., 47.8207°N, 65.9955°W, 15.VI.2009, R.P. Webster // Black spruce forest with Populus sp., in gilled mushroom (1 ♂, RWC). Saint John Co., same data as holotype (1 ♀ RWC); same data and collector as previous but 15.V.2006 // Upper margin of sea beach, in decaying sea wrack under alders (♀, 1 ♂, RWC). York Co., New Maryland, Charters Settlement, 45.8395°N, 66.7391°W, 29.III.2006, R.P. Webster, coll. // Mixed forest, flight intercept trap adjacent to composter (2 ♂, RWC). Nova Scotia, Cape Breton Highlands Nat. Park, Lone Shieling, PG729861, 100 m, 6-7.VI.1983, H. Goulet, forest malaise (1 ♂, CNC); same data except 9.VI.1983 (1 ♂, CNC); same data except 11-13.VI.1983 (1 ♂, CNC); same data except VII.1983, R. Vockeroth, malaise trap (1 ♂, 1 ♀, CNC); same data except 19.VI.1983, Y. Bousquet, interception (1 ♂, 1 ♀, CNC). Ontario, 7 km S Westport, Chaffeys Locks Biol. Station, 44°34'08N, 76 °19'15W, 23.X.1985, A. Davies, birch + maple litter beside logs (1 ♂, 1 ♀, CNC); Quebec, Parc de la Gatineau, Blind Lake, 8.V.1988, A. & Z. Smetana (1 ♂, 1 ♀, CNC); Parc de la Gatineau, visitor centre, 45.5068'N, 75.8161'W, 15-22.IV.1987, J. Denis, J. Huber & A. Davies, emergence trap at woodpile (7 ♂, 7 ♀, CNC); same data except 21-28.IV.1987 (2 ♂, 4 ♀, CNC).

Etymology.

This species is named in honor of Jon Sweeney (AFC). His long-term project on the development of a general attractant for the detection of invasive species of Cerambycidae provided numerous new species records from NB for the Cerambycidae and many other Coleoptera families.

Description.

Body length 1.7-2.0 mm, head black, pronotum dark brown and lighter than head; elytra brown to dark brown, lighter than pronotum; first two antennal segments testaceous, remaining segments dark brown becoming darker toward last segment; legs testaceous; forebody and elytra with pubescence sparse, recumbent, directed posteriad; pronotum with microsculpture distinct, dilated on sides and at base, becoming isodiametric near center, punctures widely spaced, shallow; elytra with punctation coarse, sparse, with little microsculpture, thus appearing glossy; pronotum with lateral margin arcuate in anterior two-thirds, then almost straight to hind margin, widest just before hind angle, hind angle obtuse, narrowly rounded, hind margin sinuate; mesosternum with disk irregularly rugulose, with anteromedial carinae forming semi-circular ridge with anteromedial margin, mesosternal process broad, gradually tapering to narrowly rounded apex, with long, very fine median carina; metasternum very broadly rounded between middle coxae, disk sparsely, coarsely pubescent; body shape and proportions as in Fig. 10. Male. Front tarsus with first tarsomere expanded, parallel-sided, 3x as long as wide, as long as next 4 together, remaining segments normal; posterior margin of middle trochanter almost evenly rounded, without peg setae; middle femur with hind margin expanded in apical half, with 2-3 coarse setae on expansion; middle tibia broadly arcuate, inner margin without peg-like setae or projection; hind trochanter explanate, with dense patch of short pile covering half of posteroventral surface; hind tibia expanded in ventral aspect, widest at distal third, inner margin obliquely excavate in apical half, with dense patch of short erect setae near apex. Tergite VII triangular in shape, posterior margin truncate at apex (Fig. 12); posterior margin of sternite VII broadly rounded with a deep semicircular emargination (Fig. 13). Median lobe of aedeagus with an angular subapical part in lateral view, without obvious darkened internal structures, other characters as illustrated (Fig. 11). Female. Similar to male, but first tarsal segment only slightly expanded; middle tibia nearly straight. Tergite VII similar in shape to that of male; sternite VII without emargination.

Distribution.

This species is known from MB, ON, QC, NB, and NS in Canada.

Natural history.

In NB, this species was found in a red oak forest, mature hardwood forest, black spruce ( Picea mariana (Mill.) BSP) forest with Populus sp., a mixed forest, and on a sea beach. Specimens were collected from decaying Tricholoma sp., a gilled mushroom, decaying sea wrack, a Lindgren funnel trap, and a flight intercept trap adjacent to a composter. Elsewhere, this species was collected from mushrooms, moose dung, a mammal burrow, birch ( Betula ) and maple ( Acer ) litter beside logs, and from an emergence trap at a wood pile; some specimens were captured in malaise and flight intercept traps. Adults were collected from March to October.

Comments.

We compared the genitalia of the types of all known North American species and available illustrations of the genitalia of all Palearctic species and found none matching this species, which led to the conclusion that this species was undescribed. There are several other species of Proteinus ( Proteinus atomarius Erichson, Proteinus basalis Mäklin, Proteinus brachypterus (Fabricius), Proteinus collaris Hatch, Proteinus densipennis Bernhauer, Proteinus limbatus Mäklin [all examined]) reported from Canada, including a number of undescribed species (in CNC), that are mostly western in distribution. However, it is beyond the scope of this publication to present a comparison of our newly described species with all of the other North American species until this genus is revised. We therefore provide comparisons only for the five species known to occur in NB. The external morphology has a limited number of diagnostic features and the shape and structure of the median lobe of the aedeagus are the most reliable for species level identification.

Proteinus hughesi , Proteinus parvulus , and Proteinus sweeneyi are very similar in coloration and general habitus but differ most notably in characters of the pronotum, middle tibia, and the shape of the aedeagus (Figs 2, 6-7, 11) in the males. Males of Proteinus hughesi have a row of peg-like setae along the inner margin of the mesotibia, which are absent in Proteinus parvulus and Proteinus sweeneyi (Fig. 1). The mesotibia of Proteinus parvulus bears a small fin-like projection at the apex of the inner margin (Fig. 5), while in Proteinus sweeneyi the middle tibia is without any modification of the inner margin (Fig. 10). Females are more difficult to separate but they differ in the shape and microsculpture of the pronotum. In Proteinus sweeneyi , the pronotal microsculpture is dilated laterally and basally, becoming isodiametric only near the center; in Proteinus parvulus and Proteinus hughesi , the microsculpture is isodiametric on nearly all of the pronotum. In Proteinus hughesi , the pronotum is widest near the base, with the lateral margins arcuate on the anterior third, then straight to the almost rectangular hind angles; in Proteinus parvulus , the lateral margin is arcuate throughout, with the widest point near the middle and the hind angle is obtuse. Proteinus acadiensis and Proteinus pseudothomasi differ from the above three species by their coloration (light brown or reddish brown), the lack of modification of the middle and hind legs in the males (the middle tibia is arcuate in Proteinus acadiensis ), and the shape of the genitalia (see Figs 4, 31, 32 for Proteinus pseudothomasi and Figs 5, 33 for Proteinus acadiensis in Klimaszewski et al. (2005)).