Laccophilus duplex 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 duplex Sharp, 1882

( Figs 1B , 2B , 3B , 4C )

= Laccophilus optatus 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 (11ex); 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 (1ex) TOLEDO: Bladen NR, Tyre track pools, 16°33'4,82"N, 88°42'58,08"W, 17.IV.2015, Leg. K. Scheers & A. Thomaes (1ex); Punta Gorda, temp. stream in forest, 16°06'37,6"N, 88°49'18,8"W, 25.IV.2015, Leg. K. Scheers & A. Thomaes (1ex); Punta Gorda, tyre track puddle, 16°05'24"N, 88°51'6,5"W, 25.IV.2015, Leg. K. Scheers & A. Thomaes (1ex); Punta Gorda, small stream, 16°05'17,8"N, 88°52'4"W, 25.IV.2015, Leg. K. Scheers & A. Thomaes (2ex); Golden Stream CP, puddle temp. stream, 16°22'10,6"N, 88°47'10,5"W, 28.IV.2015, Leg. K. Scheers & A. Thomaes (1ex); Golden Stream CP, Golden stream, 16°22'8"N, 88°47'59,4"W, 30.IV.2015, Leg. K. Scheers & A. Thomaes (3ex); San Miguel, puddle in intermittent stream, 16°16'52,5"N, 88°53'3,1"W, 02.V.2015, Leg. K. Scheers & A. Thomaes (45ex); San Miguel, pool in intermittent stream, 16°37'43,6"N, 88°33'28,8"W, 02.V.2015, Leg. K. Scheers & A. Thomaes (3ex) .

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7 DIAGNOSIS. TL: 3.8–4.3 mm; MW: 2.1–2.3 mm. Head testaceous, pronotum same color as head but often with a slim darker area near the base. Elytra testaceous, clouded with black and with pale markings present along the base, suture, lateral margins and the apex. The basal markings, although variable, are quite extensive and form an almost complete basal band ( Fig. 1B ). Ventral parts testaceous with the metacoxal plates narrowly darkened to pitchy black along the lateral and anterior margins ( Fig. 2B ). Male genitalia with median lobe swollen at the base ( Fig. 3B ).

SIMILAR SPECIES. The elytral markings of Laccophilus duplex are very similar to those of L. oscillator laevipennis but the markings in the latter are much more reduced and seldom confluent. Furthermore L. duplex has the metacoxal plates testaceous and at most narrowly darkened along the margins, whereas L. oscillator laevipennis has the metacoxal plates completely piceous ( Fig. 2B, 2E ).

DISTRIBUTION. Belize (first records), Brazil, Costa Rica, El Salvador, Honduras, Mexico (Chiapas, Nuevo Leon, San Luis Potosi, Tamaulipas, Veracruz), Nicaragua.

ECOLOGY. According to ZIMMERMAN (1970), this species occurs at low altitudes but above the coastal plain. He collected it in heavily shaded, shallow, clear streams with gravel bottoms and in roadside ditches. During our survey in Belize, L. duplex was collected in intermittent and permanent streams, both in the forest and open country ( Fig. 5 ). This species was also encountered with single specimens in puddles in tyre tracks and was present close to sea level.

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).