Nebria baumanni Kavanaugh, 2015

Kavanaugh, David H., 2015, A New Species of Nebria Latreille (Insecta: Coleoptera: Carabidae: Nebriini) from the Spring Mountains of Southern Nevada, Proceedings of the California Academy of Sciences 62 (18), pp. 441-450 : 442-444

Nebria baumanni Kavanaugh , new species

Figures 1 , 2A, 3A, 4A, 5A-B, 6A, 7

TYPE MATERIAL.— Holotype ( Fig. 1 ), a male, deposited in CAS, labeled: “ NV Clark Co. Deer Crk Spring Mtns 9 June ’82 Baumann-Clark” / “ HOLOTYPE: Nebria baumanni Kavanaugh sp. nov. 2015” [red label]/ “ California Academy of Sciences Type No. 18992” . Paratypes (total of 3): 2 females in BYUC and 1 female in CAS with same locality label as holotype, but with the following label: “ PARATYPE: Nebria baumanni Kavanaugh sp. nov. 2015” [yellow label] .

TYPE LOCALITY.— U.S.A., Nevada, Clark County, Spring Mountains, Deer Creek .

DERIVATION OF SPECIES NAME.— It is my great pleasure to name this species in honor of Richard Baumann, who, along with Sean Clark, collected the type series of this species. Throughout his outstanding career, Dr. Baumann and his students have sampled arthropod diversity in the Great Basin and Intermountain regions of the American West more extensively than perhaps any other team. The material that they have collected and made available to others for study, including the specimens described here, have added tremendously to our knowledge of this vast and distinctive region. The species epithet is the Latinized form of his surname name in the genitive case.

DIAGNOSIS.— Adults of this species can be distinguished from those of all other Nearctic Nebria species by the following combination of character states: size moderate for genus, SBL of male = 10.4 mm, of females 10.7 to 11.0 mm; body ( Fig. 1 ) black to piceous, dorsal surface without metallic reflection; vertex of head with a pair of paramedial pale spots; elytral microsculpture comprised of moderately impressed isodiametric meshes; antennal scape (Fig. 2A) short, distinctly narrowed basally, widest subapically; pronotum (Fig. 3A) with basal angles rectangular or slightly obtuse, lateral margins with basal sinuation long and deep, sides parallel or slightly convergent basally, with a slight lateral convexity anterior to hind angle in most individuals, lateral margination (“lateral bead”) obliterated from basal one-fifth (posterior to basolateral sinuation), midlateral and basolateral setae present; elytral silhouette subrectangular, distinctly narrowed basally, widest distinctly posterior to middle, lateral margins nearly straight in basal half, humeral angles obtuse and moderately rounded, humeral carinae absent, elytral apices ( Fig. 4A ) smoothly arcuate laterally and obliquely truncate medially, roundly angulate apically, parascutellar setiferous pore puncture absent; hindwings long but narrowed; median lobe of male

FIGURE 2. Digital images of right antennal scape, dorsal aspect. A. Nebria aedeagus with shaft thick, evenly baumanni sp. nov.; B. Nebria giulianii Kavanaugh. Scale line = 0.5 mm. arcuate, apical lamella moderately long, slightly enlarged and evenly rounded apically in left lateral view ( Fig. 5A ), shaft distinctly thickened in region of apical orifice in dorsal view ( Fig. 5B ); bursa copulatrix of female genitalia ( Fig. 6A ) with a posterordorsal lobe and a distinct bursal sclerite in the posterior wall of that lobe, spermathecal duct inserted at base of the bursal sclerite on posterior face of posterodorsal lobe; specimen from Spring Mountains of Clark County, Nevada ( Fig. 7).

Members of this species are most similar externally to those of Nebria giulianii Kavanaugh and other members of the meanyi species group, with which they share similar overall body form and size ( Fig. 1 ). They differ from members of all the other species of this group in the following features: dorsal elytral surface without metallic reflection (distinct metallic blue, green or violet reflection seen in members of all the other species); antennal scape (Fig. 2A) short and markedly narrowed basally (scape longer and not or only slightly narrowed basally (Fig. 2B) in members of all the other species); lateral margination (“lateral bead”) of the pronotum obliterated posterior to basal sinuation of lateral margin (lateral margination distinctly defined thoughtout pronotal length in members of all the other species); elytral apices ( Fig. 4A ) smoothly arcuate laterally and obliquely truncate medially, roundly angulate apically (broadly and evenly rounded ( Fig. 4B ) in members of all the other species); median lobe of male aedeagus ( Fig. 5A ) with shaft thick and apical lamella moderately long and apically slightly enlarged (shaft slender and apical lamella short- er and not apically enlarged ( Fig. 5B ) in males of all the other species); and bursa copulatrix of female ( Fig. 6A ) with a posterodorsal lobe and bursal sclerite on posterior face of that lobe (posterodorsal lobe and bursal sclerite absent ( Fig. 6B ) from females of all the other species). See the key below to distinguish adults of N. baumanni from those of all other species known to occur in Nevada. SEXUAL DIMORPHISM.— Males and females of this species are similar in size and form and both have two pairs of posterior paramedial setae near the hind margin of sternum VII. The only apparent external difference between the sexes is in the front tarsi: in males the basal three tarsomeres of the protarsi are broad and have dense pads of adhesive setae ventrally, whereas these tarsomeres are slender and without such setal pads in females.

Figures

FIGURE 1. Digital images of holotype, Nebria baumanni sp. nov. A. Habitus, dorsal aspect; B. Labels for holotype. Scale line = 1.0 mm.

FIGURE 4. Digital images of elytral apices, dorsal aspect; A. Nebria baumanni sp. nov.; B Nebria giulianii Kavanaugh. Scale line = 0.5 mm.

FIGURES 5. Digital images of median lobe of male genitalia. A-B. Nebria baumanni sp. nov.; C-D. Nebria giulianii Kavanaugh; A and C. dorsal aspect; B and D. left lateral aspect. Scale line = 1.0 mm.

FIGURE 6. Digital images of female reproductive tract, dorsal aspect. A. Nebria baumanni sp. nov.; B. Nebria giulianii Kavanaugh; badl = anterodorsal lobe of bursa copulatrix; bpdl = posterodorsal lobe of bursa copulatrix; bs = bursal sclerite (in posterior wall of posterodorsal lobe); co = common oviduct; sd = spermathecal duct; sp = spermathecal reservoir; white circle = insertion point of spermathecal duct (at base of posterior face of dorsal lobe). Scale line = 0.5mm.