Eleodes (Blapylis) nigropilosus (LeConte, 1851)

Smith, Aaron D., Dornburg, Rebecca & Wheeler, Quentin D., 2014, Larvae of the genus Eleodes (Coleoptera, Tenebrionidae): matrix-based descriptions, cladistic analysis, and key to late instars, ZooKeys 415, pp. 217-268 : 222-225

Eleodes (Blapylis) nigropilosus (LeConte, 1851) Fig. 4A

Material examined.

Larval Eleodes nigropilosus specimens were reared from adults with the following collecting information: "USA: CA: San Diego Co. / Oceanside beach / 33.1865, -117.3778 / 14.May.2011, ADSmith". A total of 29 eggs and larvae were reared and examined for this study, of which 34 survived to the 2nd instar or beyond. The following description is based on a detailed examination of three 8-11th instar specimens.

Description.

TL: 12-15.9 mm, HW: 1.0-1.1 mm, PL: 1.3-1.5 mm, PW: 1.0-1.2 mm.

Head. Prognathous or weakly declined; weakly dorsoventrally flattened; width nearly equal to prothorax; sides rounded; strongly constricted before occipital foramen; color light to dark tan, same or nearly the same as body segments; punctation minute, moderately dense, separated by 2-4 puncture diameters. Epicranial suture stem length approximately one-third head capsule length; frontal arms sinuate, not obscured by sculpturing. Frons faintly rugose. Epicranial plates weakly rugose dorsally; lateral portions moderately setose; ventral portion of each plate with row of four to five long setae along anterior margin near buccal cavity, not confluent with setae on lateral portions of plates, and a patch of short setae medially, forming a triangular pattern with its base near the anterior margin. Two stemmata present on each epicranial plate, pigmented spots often faded. Clypeus trapezoidal, not swollen, darker medially in basal half, minutely punctate, punctation moderately dense, separated by 2-4 puncture diameters. Labrum not swollen, sides rounded, basal half more darkly pigmented, medial setal row with six to seven erect setae subapical setal row with seven to eight erect setae, anterior margin straight to weakly emarginate. Epipharynx anterior setal row with six stout spiniform setae, anterolateral margins with micro-setation; six anterior sensory papillae present, arranged in two irregular diagonal rows; four subanterior sensory papillae present, arranged as transverse row subtended by two spinose setae; eight posterior sensory papillae present, arranged in an irregular cluster. Tormae asymmetric, left torma smaller. Ligula apex and subapical dorsal surface densely micro-setose, two long subapical setae present ventrally. Hypopharyngeal sclerome pentagonal, tricuspidate. Gula distinct, trapezoidal, widest in basal half, length subequal or greater than maximum width. Antenna three segmented, cylindrical, length of first segment subequal to second.

Thorax. Thoracic tergites light tan, prothoracic sternite anterior to legs medium brown, thoracic sternites posterior to prolegs light brown. Prothoracic tergum subquadrate, 1.5 × length of meso- or metaterga; anterior transverse striated band present, darker than protergal disc; lateral margins with distinct granulated band, darker than protergal disc. Posterior transverse striated band present on all thoracic tergites, forming a gradient from darker brown anteriorly to lighter brown along posterior border. Meso- and metathoracic tergites wider than long, each with a faintly indicated sclerotized transverse line present on anterior fifth. Thoracic tergites sparsely setose on dorsal surfaces, lateral margins more densely setose. Mesothoracic spiracle simple, ovate, approximately 1.5 × size of abdominal spiracles; reduced metathoracic spiracle visible, less than one-fourth size of mesothoracic spiracle. Legs. Prothoracic leg slightly longer, much thicker than meso- and metathoracic legs; prothoracic tarsungulus strongly sclerotized, sickle-shaped; prothoracic trochanter with two stout spines ventromedially; prothoracic femur with ventromedial row of three spines, dorsal surface with faintly indicated basal sclerotized band; prothoracic tibia with ventromedial row of three to four spines, dorsal surface slightly more sclerotized than ventral surface. Mesotibia with two ventromedial spines.

Abdomen. Abdominal tergites and sternites light tan with darker transverse striated bands present along posterior margins of segments I-VIII, forming near contiguous band around segments, bands dark along anterior edge, fading to segment color posteriorly. Abdominal sternite I sparsely clothed in long erect setae from anterior margin to near midline. Abdominal laterotergites with lateral margins distinctly pigmented. Abdominal segment IX (pygidium) triangular in dorsal view, gradually reflexed to apex, urogomphi absent, apex not forming a distinct tooth, moderately clothed in short and mid length erect setae, sclerotized uniformly throughout, lacking maculations; marginal row of 14-18 socketed spines present, arranged as single row around posterior two-thirds to one half of segment. Abdominal sternites I-VIII lacking longitudinal tomentose bands along lateral margins. Pygopods short, subconical, each with 9-12 erect setae.

Diagnosis.

Eleodes nigropilosus larvae can be separated from the other currently known Eleodes species by having the posterior pigmented band around the abdominal segments forming a color gradient from dark along anterior edge and fading to the color of the rest of the segment posteriorly.

Figures

Figure 4. Lateral habitus of three Eleodes species: A Eleodes (Blapylis) nigropilosus B Eleodes (Caverneleodes) wheeleri C Eleodes (Eleodes) armatus. Scale bar = 5 mm.