Laccophilus irroratus Aube , 1838

Bistroem, Olof, Nilsson, Anders N. & Bergsten, Johannes, 2015, Taxonomic revision of Afrotropical Laccophilus Leach, 1815 (Coleoptera, Dytiscidae), ZooKeys 542, pp. 1-379 : 75-77

Taxon classification Animalia Coleoptera Dytiscidae

Laccophilus irroratus Aube, 1838 Figs 61-62, 256, 415, 535

Laccophilus irroratus Aubé 1838: 427 (original description, faunistics); Sharp 1882: 309 (description, faunistics); Kolbe 1883: 426 (description, faunistics); Régimbart 1895: 138, 141 (description, faunistics, discussion); Alluaud 1897: 212 (faunistics); Peschet 1917: 23, 24, 55 (description, faunistics); Zimmermann 1920a:20 (catalogue, faunistics); Guignot 1946c: 268 (description, faunistics); Vinson 1956: 29 (faunistics, list, biology); Guignot 1957a: 98 (faunistics); Guignot 1959a: 557, 560, 562 (description, faunistics); Guignot 1961a: 930 (faunistics); Vinson 1967: 314 (faunistics, list); Wewalka 1980: 729, 730 (faunistics); Bameul 1984: 93, 102 (faunistics); Nilsson 2001: 245 (catalogue, faunistics); Pederzani and Reintjes 2002: 40 (faunistics); Nilsson 2015: 213 (catalogue, faunistics).

Type locality.

Réunion: Ile de France et Bourbon.

Type material studied

(1 ex.): Holotype, male: "Data in NHRS JLKB 000030278 / Laccophilus irroratus mihi h. in ile de France D. Latereille / Ex Musaeo Dejean / D. Sharp Monogr. / irroratus / Dr. Régimbart 1893 / Coll. Oberthur" (MNHN).

Additional material studied

(21 exs.). Mauritius: "I. Maurice Montrésor Ch. Alluaud 1893 / male symbol / Museum Paris coll. Maurice Régimbart” (1 ex. MNHN); "I. Maurice Mon Désert P. Carie Fév. 1903 / Laccophilus irroratus Aubé / Museum Paris coll. 1945 R. Peschet" (1 ex. MNHN); "Ile Maurice / de Borre" (3 exs. MHNG); "Ins. Mauritius Westw." (1 ex. ZMHB). - Reunion: "La Reunion Palmistes Ch. Alluaud 1893 / Museum Paris coll. Maurice Régimbart 1908 / irroratus Aubé” (2 exs. MNHN; habitus in Fig. 415); "S St. Benoit NW Cambourg, ca. 250 m 2-3.1. 1999 Wewalka / Laccophilus irroratus Aubé Wewalka det. 99" (2 exs. CGW, 1 ex. MZH); "E St. Joseph Riv. Langevin 250 m 28.12. 1998 leg. Wewalka / Laccophilus irroratus Aubé Wewalka det. 99" (4 exs. CGW, 4 exs. MZH); "Plaine des Cafres 3.3. 1935 Vinson" (1 ex. MNHN); "Ins. I. Fr. Dufr." (1 ex. ZMHB).

Diagnosis.

Laccophilus irroratus is characterized by large body size, peculiar elytral colour pattern and penis, which is different from all other African Laccophilus species; penis in lateral aspect quite delicate, distinctly curved and simple, exhibiting minor modifications.

Description.

Body length 4.0-4.3 mm, breadth 2.4-2.6 mm. Dorsal, colour pattern of body stable, exhibits only minor variation (Fig. 415).

Head: Pale ferruginous, posteriorly close to pronotum with narrow but distinct, dark ferrugineous area. Rather shiny, although distinctly microsculptured. Reticulation double, large meshes contain 3-5 small meshes. In middle of head small meshes in part reduced. At eyes with scattered, fine punctures; area with punctures extends towards middle of head.

Pronotum: Pale ferrugineous to ferrugineous. Anteriorly, at level of eyes with a broad, black to dark ferrugineous area. At base with a quite narrow, black to dark ferrugineous area, which is medially somewhat enlarged. Delimitation of darker areas is somewhat vague. Rather shiny, although distinctly microsculptured; reticulation double. Large meshes distinct while small meshes, especially medially, are fine, in part hardly visible or totally absent. Punctures absent, except in frontal part and laterally where puncture very fine and scattered.

Elytra: Pale ferrugineous, with distinct, only slightly variable, dark ferrugineous irrorations (Fig. 415). One specimen with quite broad, transverse, pale area frontally. Rather shiny, although distinctly microsculptured; reticulation double. Large meshes contain, when discernible, 3-5 fine meshes. Fine meshes sometimes obliterated. Fine scattered punctures form a discal row of punctures. Scattered, irregular punctures indicate presence of dorsolateral and lateral rows of punctures. Laterally, with a pre-apical furrow.

Ventral aspect: Blackish ferrugineous to dark ferrugineous, no distinct colour pattern but three basal ventrites are somewhat paler than apical ones. Rather shiny, in part with very fine microsculpture. Almost impunctate, except apical ventrite, with scattered fine punctures, and frontally on metathorax, with fine, fairly dense punctures. Abdominal ventrites with fine, curved striae. Metacoxal plates with about 10 shallow and in part slightly indistinct furrows. Metacoxal process not modified. Apical ventrite, symmetric (no knob discernible) (Fig. 61). Prosternal process rather narrow, apex only slightly extended, pointed.

Legs: Pro- and mesotarsus slender, somewhat extended. Segments provided with suckers.

Male genitalia: Penis delicate, in lateral aspect distinctly curved; apex simple and exhibits hardly any modifications (Fig. 256).

Female: Pro- and mesotarsus slender. Apical ventrite (Fig. 62).

Distribution.

Mascarene Islands; Réunion, Mauritius (Fig. 535). Guignot (1957a) gives also Rodriguez. Laccophilus irroratus is an endemic species of Mascarene Islands ( Guignot 1961a).

Collecting circumstances.

Almost unknown. Reported in rock pools of slow stream ( Vinson 1956).