Laccophilus minutus (Linnaeus, 1758)

Bistroem, Olof, Nilsson, Anders N. & Bergsten, Johannes, 2015, Taxonomic revision of Afrotropical Laccophilus Leach, 1815 (Coleoptera, Dytiscidae), ZooKeys 542, pp. 1-379 : 25-27

Taxon classification Animalia Coleoptera Dytiscidae

Laccophilus minutus (Linnaeus, 1758) Figs 27-28, 226, 388, 529

Dytiscus minutus Linnaeus 1758: 412 (original description, faunistics).

Laccophilus minutus (Linnaeus), Leach 1815: 673 (description, biology); Aubé 1838: 417 (description, faunistics); Lucas 1846: 94 (faunistics); Reiche 1872: 23 (faunistics, list); Régimbart 1895: 132 (faunistics; given as Laccophilus obscurus Panzer, junior synonym of Laccophilus minutus ); Zimmermann 1920a: 21 (catalogue); Bertrand 1928b: 274 (juvenile description); Zimmermann 1930: 14 (description, faunistics); Lindberg 1939: 11, 13, 29 (biology, faunistics); Brinck 1943: 154 (faunistics); Balfour-Browne 1951: 193 (discussion); Sanfilippo 1955: 1 (faunistics, biology); Guignot 1956b: 220 (discussion); Guignot 1959a: 579, 583 (redescription, faunistics); Angelini 1982: 82 (faunistics); El Alaoui 1983: 133, 135 (faunistics); Nilsson 2001: 247 (catalogue, faunistics); Nilsson 2003: 76 (faunistics, list); Bennas and Sàinz-Cantero 2006: 59, 62 (faunistics, list); Nilsson 2015: 214 (catalogue, faunistics). [Comments: Only references referring to Africa are listed. The list of synonyms and references is accordingly, not complete. We refer to World catalogue of Nilsson (2015)]

Type locality.

Europe.

Type material

(not examined): “Europe”. Type specimen deposited in The Linnean Collections, London, UK (item data: LINN 6347 Dytiscus minutus (Ins. Linn.), www.linnean.org).

African material studied

(49 exs.). Morocco: "Tanger 25-29.4. 1926 Lindberg" (6 exs. MZH); "Tiflet-Oulmes 18.3.1961 Lindberg-Meinander" (4 exs. MZH; habitus in Fig. 388); "Sp. Mor., at Tangier border 8.7.1955" (1 ex. USNM); "Rabat 3-4.5. 1926 Lindberg" (2 exs. MZH); "Gharb 7.7. 1926 Lindberg" (11 exs. MZH); "Marrakesch 21-23.5. 1926 Lindberg" (6 exs. MZH); "Dayet Jerans (lake) 11 km E.N.E. Ifrane 5400 ft. 28.5. 1961 / P.N. Lawrence" (1 ex. BMNH); "Middle Atlas, nr Ifrane 28.5. 1961 Dayet Jerane P.N. Lawrence" (1 ex. BMNH, 1 ex. MZH); "Oued Zad 65 km S Ifrane 21.5. 1961 / P. N. Lawrence / Tiny pond, flooded grass" (1 ex. BMNH); "Fr. Mor., Petit Jean 9.7. 1955 D.L. Lauck" (6 exs. USNM, 2 exs. MZH); "Sp. Mor., El Kaar, El Kebir 8.7.1955 D.R. Lauck" (2 exs. USNM). - Algeria: "Bouqie 17.7. 1955 D.R. Lauck" (1 ex. USNM). - Tunisia: "Tunis J. Sahlb." (1 ex. MZH); "Tunisien 2.9. 1991 5 km W Utique Schödl” (1 ex. NMW); "Tunisien 3.8. 1991, 22 km N Jendouba Schödl” (1 ex. NMW). - Libya: "Libya bor. or. 495 m a.s.l. prov. Al Jabal Al Akhdar, 5 km SW Al Bayda 18.5.2002 / 32°43'41.9"N, 21°41'14"E, Reiter A. lgt." (1 ex. NMPC). [Comment: Only material collected from Africa is listed.]

Diagnosis.

Laccophilus minutus resembles most of Laccophilus mateui and Laccophilus sordidus , both species also lacking stridulation apparatus on metacoxal plates. Laccophilus minutus is separated from the two close species by having smaller body and more delicate and slender penis (Figs 226, 227, 228).

Description.

Body length 4.0-4.6 mm, width 2.2-2.5 mm. Dorsal, aspect of body without distinct colour pattern. On elytra vague, slightly darker areas may sometimes be discerned (Fig. 388).

Head: Pale ferrugineous. Slightly mat to rather shiny, finely microsculptured. Reticulation double. Large meshes slightly more strongly developed than fine meshes. Large meshes may contain 3-6 small meshes. Impunctate, except at inner eye-margin, with an irregular row of punctures. Additionally close to eyes with a vertically located row of a few punctures.

Pronotum: Pale ferrugineous; lacks distinct colour pattern. Impunctate, except at frontal and lateral margins, where fine and sparse, irregular punctures are discernible. Rather shiny to submat, finely microsculptured. Reticulation double. Large meshes a little more strongly developed than small meshes; may contain 3-6 small meshes. Pronotum base posteriorly in middle produced backwards.

Elytra: Pale ferrugineous, without distinct colour pattern. Sometimes elytra with some vague, irregular, slightly darker areas (Fig. 388). Almost impunctate. Discally with sparse, fine and scattered punctures forming a vague row. Additionally, some scattered, fine punctures may be discerned at location of dorsolateral and lateral rows. Pre-apical, lateral row of punctures form a fine furrow, provided with fine hairs. Rather shiny, although finely microsculptured. Reticulation double. Large meshes a little more strongly developed; may contain 3-6 smaller meshes.

Ventral aspect: Pale ferrugineous to ferrugineous, without distinct colour pattern. Almost impunctate, Abdomen apically with some fine punctures. Rather shiny, very finely and in part indistinctly microsculptured. Ventrites with fine, slightly curved striae. Metacoxal plates with about 10 fine, shallow, transversely located furrows. No stridulatory apparatus. Apical ventrite almost symmetric, lacks lateral knob; finely striated, with distinct lateral impressions (Fig. 27). Prosternal process rather slender; posteriorly, moderately extended, apex pointed.

Legs: Pale ferrugineous to ferrugineous. Pro- and mesotarsus somewhat enlarged, provided with suckers.

Male genitalia: Aedeagus almost as in Laccophilus mateui but more delicate in lateral aspect (Fig. 226).

Female: Pro- and mesotarsus slender. Apical ventrite lacks distinct lateral impressions; impressions reduced to fine lines (Fig. 28).

Distribution.

Morocco, Algeria, Tunisia, Libya (Fig. 529).

Collecting circumstances.

According to Nilsson and Holmen (1995), probably focusing from Nordic perspective, main habitat is permanent water body as lakes and ponds with stagnant water. Vegetation of water body is sparse or absent. Lindberg (1939) briefly described some sampling sites of Laccophilus minutus in Morocco. The species was collected both in standing and running waters. Collected also from an almost dried up river-bed with rich vegetation. Adults are capable of flight.