Laccophilus oscillator laevipennis Sharp, 1882

Scheers, Kevin, Thomaes, Arno, Hájek, Zimmerman, Michat & Reynoso-Velasco, 2017, The Laccophilinae Gistel, 1848 of Belize (Coleoptera: Dytiscidae), Belgian Journal of Entomology 65, pp. 1-18 : 1-18

Laccophilus oscillator laevipennis Sharp, 1882

( Figs 1F , 2E , 3E , 4F )

= Laccophilus laevipennis Sharp, 1882

MATERIAL STUDIED. STANN CREEK: Cockscomb Basin Wildlife Sanctuary , stream and puddles on rock, 16°46'50,44"N, 88°26'28,6"W, 06.V.2015, Leg. K. Scheers & A. Thomaes (10ex); Cockscomb Basin Wildlife Sanctuary, edge of stream with leaf litter, 16°46'55,4"N, 88°27'41,1"W, 06.V.2015, Leg. K. Scheers & A. Thomaes (4ex); Cockscomb Basin Wildlife Sanctuary, pool under waterfall and puddles on rockface, 16°46'22,8"N, 88°27'3,3"W, 07.V.2015, Leg. K. Scheers & A. Thomaes (3ex); Cockscomb Basin Wildlife Sanctuary, slow part of stream, 16°46'40,5"N, 88°27'29,8"W, 07.V.2015, Leg. K. Scheers & A. Thomaes (2ex); Maya Center, stream, 16°47'48,9"N, 88°22'50,2"W, 07.V.2015, Leg. K. Scheers & A. Thomaes (3ex) TOLEDO: Bladen NR, Tyre track pools, 16°33'4,82"N, 88°42'58,08"W, 17.IV.2015, Leg. K. Scheers & A. Thomaes (8ex); Bladen NR, pond transition savannah-forest, 16°32'26,3"N, 88°42'57,1"W, 20.IV.2015, Leg K. Scheers & A. Thomaes (4ex); Bladen NR, pond in forest, 16°32'55,3"N, 88°43'1,7"W, 19.IV.2015, Leg. K. Scheers & A. Thomaes (7ex); Bladen NR, pond in forest, 16°32'59,4"N, 88°43'0,8"W, 19.IV.2015, Leg. K. Scheers & A. Thomaes (3ex); Bladen NR, stream near spring, 16°33'27,4"N, 88°43'56,4"W, 21.IV.2015, Leg. K. Scheers & A. Thomaes (2ex); Punta Gorda, temp. stream in forest, 16°06'37,6"N, 88°49'18,8"W, 25.IV.2015, Leg. K. Scheers & A. Thomaes (9ex); Punta Gorda, tyre track puddle, 16°05'24"N, 88°51'6,5"W, 25.IV.2015, Leg. K. Scheers & A. Thomaes (7ex); Punta Gorda, small stream, 16°05'27,3"N, 88°51'32,7"W, 25.IV.2015, Leg. K. Scheers & A. Thomaes (3ex); Punta Gorda, pool temp. stream in forest, 16°05'42,2"N, 88°49'38,9"W, 25.IV.2015, Leg. K. Scheers & A. Thomaes (3ex); Golden Stream CP, temp. stream in forest, 16°23'33"N, 88°46'33,8"W, 26.IV.2015, Leg. K. Scheers & A. Thomaes (24ex); Golden Stream CP, puddle near Golden Stream, 16°21'50,8"N, 88°47'55,7"W, 27.IV.2015, Leg. K. Scheers & A. Thomaes (1ex); Golden Stream CP, puddle temp. stream, 16°22'50,7"N, 88°46'45,3"W, 27.IV.2015, Leg. K. Scheers & A. Thomaes (4ex); Golden Stream CP, Golden stream, 16°22'8"N, 88°47'59,4"W, 30.IV.2015, Leg. K. Scheers & A. Thomaes (6ex); Red Banks, stream in forest, 16°37'43,6"N, 88°33'28,8"W, 01.V.2015, Leg. K. Scheers & A. Thomaes (7ex); San Miguel, puddle in intermittent stream, 16°16'52,5"N, 88°53'3,1"W, 02.V.2015, Leg. K. Scheers & A. Thomaes (16ex) .

PUBLISHED RECORDS. SITES & REYNOSO-VELASCO, 2015

12 DIAGNOSIS. TL: 3.5–4.1 mm; MW: 2.0–2.4 mm. Head testaceous with a more or less distinct darker band posteriorly, pronotum same color as head with and more or less indistinct darker area near the base. Elytra testaceous clouded with black, pale markings along the base, suture, lateral margins and the apex ( Fig. 1F ). Ventral parts testaceous with the metacoxal plates dark brown to pitchy black ( Fig. 2E ). Median lobe of male genitalia with wide base and narrow apical half ( Fig. 3E ).

DISTRIBUTION. Belize, Costa Rica, Mexico (Chiapas, Jalisco, Oaxaca), Nicaragua.

ECOLOGY. According to ZIMMERMAN (1970) this subspecies occurs in mountainous regions in tropical deciduous forest. This species (both this subspecies and the nominate form) is typical of rocky mountain streams that are frequently subjected to high currents. He collected the nominate form by sweeping underneath large boulders that are subject to heavy currents. In Belize it is the most common species of Dytiscidae present in forest streams where it is almost a constant. We found L. oscillator laevipennis most abundant in leaf packs in slow flowing parts of forest streams and small rivers with a substrate of gravel or rock but it was often also collected between the exposed gravel and boulders ( Fig. 5 ). Furthermore this species was also encountered in lentic habitats in the forested areas where it occurred in puddles in tyre tracks and in heavily shaded ponds with a thick layer of leaf litter where other Laccophilus species were absent.

Figures

Fig. 1. Dorsal view of Laccophilinae species in Belize. A, Laccomimus pumilio (LeConte, 1878); B, Laccophilus duplex Sharp, 1882; C-D, Female of L. fasciatus fasciatus Aubé, 1838, C, with distinct elytral flange, D, without elytral flange; E, L. gentilis suavis Sharp, 1882; F, L. oscillator laevipennis Sharp, 1882; G, L. ovatus zapotecus Zimmerman, 1970; H, L. proximus Say, 1823; I, L. spangleri Zimmerman, 1970 (Photograph: F. Trus).

Fig. 2. Ventral view of Laccophilinae species in Belize. A, Laccomimus pumilio (LeConte, 1878); B, Laccophilus duplex Sharp, 1882 (pale specimen); C, L. fasciatus fasciatus Aubé, 1838; D, L. gentilis suavis Sharp, 1882; E, L. oscillator laevipennis Sharp, 1882; F, L. ovatus zapotecus Zimmerman, 1970; G, L. proximus Say, 1823; H, L. spangleri Zimmerman, 1970 (Photograph: F. Trus).

Fig. 3. Median lobe, left lateral view. A, Laccomimus pumilio (LeConte, 1878); B, Laccophilus duplex Sharp, 1882; C, L. fasciatus fasciatus Aubé, 1838; D, L. gentilis suavis Sharp, 1882; E, L. oscillator laevipennis Sharp, 1882; F, L. ovatus zapotecus Zimmerman, 1970; G, L. proximus Say, 1823; H, L. spangleri Zimmerman, 1970.

Fig. 4. Known distribution of Laccophilinae species in Belize. A, sampled sites; B, Laccomimus pumilio (LeConte, 1878); C, Laccophilus duplex Sharp, 1882; D, L. fasciatus fasciatus Aubé, 1838; E, L. gentilis suavis Sharp, 1882; F, L. oscillator laevipennis Sharp, 1882; G, L. ovatus zapotecus Zimmerman, 1970; H, L. proximus Say, 1823; I, L. spangleri Zimmerman, 1970 (white dots indicate sampled sites and black dots indicate sites where the species is recorded, elevation map as background in which dark shading increases with height).

Fig. 5. Permanent stream in the Cockscomb Basin Wildlife Sanctuary, typical habitat of Laccophilus duplex Sharp, 1882 and L. oscillator laevipennis Sharp, 1882 (Photograph: K. Scheers).