Laccophilus burgeoni Gschwendtner, 1930

Bistroem, Olof, Nilsson, Anders N. & Bergsten, Johannes, 2015, Taxonomic revision of Afrotropical Laccophilus Leach, 1815 (Coleoptera, Dytiscidae), ZooKeys 542, pp. 1-379 : 200-202

Taxon classification Animalia Coleoptera Dytiscidae

Laccophilus burgeoni Gschwendtner, 1930 Figs 166-167, 348-349, 495-496, 565

Laccophilus burgeoni Gschwendtner 1930: 89 (original description, faunistics); Guignot 1946c: 282 (description, faunistics); Guignot 1953e: 4 (discussion); Guignot 1954: 25 (discussion); Guignot 1959a: 557, 563 (description, faunistics); Nilsson 2001: 241 (catalogue, faunistics); Pederzani and Reintjes 2002: 38 (faunistics); Nilsson 2015: 210 (catalogue, faunistics).

Laccophilus wittei Guignot 1952b: 3 (original description, faunistics); Guignot 1954: 28 (description, faunistics); Guignot 1955a: 29, 37 (faunistics, biology); Guignot 1959a: 544, 550 (description, faunistics); Medler 1980: 155 (faunistics, list); Nilsson 2001: 253 (catalogue, faunistics); Nilsson 2015: 219 (catalogue, faunistics). New synonym.

Type localities.

Laccophilus burgeoni : Zaire: de Kindu.

Laccophilus wittei : Zaire: PNU, Riv. Difiringi.

Type material studied

(5 exs.). Laccophilus burgeoni : Holotype: female: "Type Gschw. / Musée du Congo K. 300 de Kindu 14.V. 1911 L. Burgeon / Col. Gschwendtner / Laccophilus burgeoni Gschw. det. Gschwendtner / Type" (OLML).

Laccophilus wittei : Holotype: male: "Holotypus / Congo belge PNU Difirinji affl. g. Lufira (700 m) 27-IV-1949 Mis. G.F. de Witte 2732a / Coll. Mus. Congo (ex. coll. I.P.N.C.B.) / Laccophilus wittei Guign. Type, male symbol / Guignot det. 1952 Laccophilus wittei Guign. Type, male symbol" (MRAC). - Paratypes, males: "Congo belge: PNU Ganza pr., r. Kamandula (860 m) saline, 1-VI-1949 Mis. G.F, de Witte, 2648a / Paratype / F. Guignot det., 1953 Laccophilus wittei sp. n. / R.I.Sc.N.B. I.G. 24.054" (1 ex. IRSNB; habitus in Fig. 495); same data but "Loie affl. g. Lufira (1000 m) 6-III-1949" and “2666a” (1 ex. IRSNB); "Congo belge PNU Kabangey 1050 m VI-1949 de Witte / male symbol / paratype" (1 ex. MNHN). [Comments: Some confusion prevailed regarding status and location of the holotype of Laccophilus burgeoni . One specimen, deposited in MRAC is labelled as holotype of the species and the specimen is provided with label-data which is in accordance with original description. In Linz museum (OLML), however, there are two specimens labelled as types of Laccophilus burgeoni , both also provided with corresponding label data. Original description states that Laccophilus burgeoni is described on the basis of a single female specimen. All, three involved specimens are females. Having read the morphological description of the species, it is evident that the specimen in MRAC cannot be the holotype. On the other hand the description fits well with the two specimens in OLML, but how can there be two specimens marked as type when only one is mentioned in the description? This dilemma is interpreted as a case of later mislabelling in OLML. Original description gives as label data "K. 300 de Kindu (L. Burgeon)". The label data of one of the two specimens coincides exactly with this while the other specimen is labelled "Kindu L. Burgeon". Accordingly, the first mentioned specimen is considered to be the holotype.]

Additional material studied

(80 exs.). Nigeria: "River 3,5 mi. from Jos on Kaduna rd. 13.IV. 1963 JOC." (2 exs. AMGS); "Trib. R. Gagere en rte Zaria-Katsina 5.10. 1963 JOC." (1 ex. AMGS); "Dam, Vom?, Jos Plateau 11.IV. 1963 JOC." (1 ex. AMGS); "Stream at Assob 36 mi. from Jos 13.IV. 1963 JOC." (1 ex. AMGS); "R. Kaduna 4,5 mi. from Jos 13.IV. 1963 JOC." (2 exs. AMGS); "Stream, escarpment Jos-Wambe rd. 13.IV. 1963 JOC." (17 exs. AMGS); "Plateau Prov. Jos 14-17.3. 1949 Malkin leg. / Muddy running stream, gravel bottom" (38 exs. BMNH, 5 exs. MZH; habitus in Fig. 496); "Zaria 1969 Brancucci" (1 ex. NHMB). - Sudan: "Equatoria Lalyo-Juba 26-27.2. 1963 Linnavuori" (1 ex. MZH). - Zaire: "Type Gschw. / Musée du Congo Kindu L. Burgeon / Coll. Gschwendtner / Laccophilus burgeoni Gschw. det. Gschwendtner / Type" (1 ex. OLML; not type material); "Ituri Mahagi 19.V. 1925 / Laccophilus wittei Gschw. det. Guignot 1959" (1 ex. NHMB); "Lukonzolwa 9-17.2. 1931 de Witte" (1 ex. NHMB); "Musosa / 10. 1939 Bredo" (1 wx. MNHN); "PNU Mabwe 2.3. 1949 de Witte" (1 ex. MNHN); "Elisabethville 1935 Richard" (1 ex. NHMB). - Uganda: "Arua 24.2. 1931 Hancock" (3 exs. BMNH). - Tanzania: "NW Usagara 1700-1900 m 15.12. 1912 / Laccophilus lineatus Aubé det. Zimmermann / Laccophilus wittei Guign. det. Brancucci 1982" (1 ex. ZMHB); "Iringa 1.10. 1964 ex pond James" (1 ex. CGC).

Comments on synonymy.

Holotypes of Laccophilus burgeoni and Laccophilus wittei have been examined and compared. Minor difference is present in appearance of dorsal colour pattern but at least for the time being this is considered a case of ordinary variation within one species. Laccophilus burgeoni , being the older name is the valid name of the species.

Diagnosis.

Laccophilus burgeoni resembles much of Laccophilus lineatus . The two species are generally distinguished by differences in appearance of external colour pattern and by study of male genitalia. In Laccophilus burgeoni dark markings of pronotum are generally restricted to a narrow basal area and very rarely to a vague anterior marking (in Laccophilus lineatus both anterior and posterior dark markings of pronotum are distinct). Apex of penis in Laccophilus lineatus is shaped as a distinct knob while corresponding feature in Laccophilus burgeoni is absent or at most developed to a minor knob.

Description.

Body length 3.6-3.8 mm, width 1.9-2.2 mm. Habitus and dorsal colour pattern; exhibit some variation.

Head: pale ferrugineous. Rather shiny, although finely reticulated. Double reticulation fine but clearly discernible; large meshes contain two to six small meshes. At eyes with fine punctures.

Pronotum: Pale ferrugineous. Medially, at foremargin with vague, slightly darker area (area sometimes hardly discernible). Medially, at base with distinct but narrow, dark ferrugineous marking. Rather shiny, although finely reticulated. Reticulation partly double. Larger meshes contain two to nine small meshes. At margins with fine and irregular punctures, except basally in middle; impunctate.

Elytra: Colour pattern variable. Pale ferrugineous, with blackish to dark ferrugineous markings. Rarely, some specimens have slightly broader longitudinal lines, in part touching each other or than dark markings anteriorly on elytra are totally lacking (Figs 495-496). Submat due to dense microsculpture. Extensively with double reticulation; laterally and posteriorly double reticulation becomes indistinct. Almost impunctate; three indistinct, longitudinal rows of scattered, fine punctures may be discerned. Lateral, pre-apical furrow fine, pubescent.

Ventral aspect: Pale ferrugineous to ferrugineous, sometimes with vague, lateral, somewhat darker areas. Rather shiny, with very fine, in part hardly visible microsculpture. Abdomen with very fine, curved striae. Almost impunctate. Transversely on metacoxal plates located, shallow furrows discernible but weakly developed and in part reduced. Prosternal process slender, apex extended and pointed. Metacoxal process not modified. Apical ventrite with sublateral knob (Fig. 166).

Legs: Pale ferrugineous. Pro- and mesotarsus somewhat enlarged, provided with suckers. Claws of pro- and mesotarsus slightly extended, moderately curved.

Male: Genitalia: Penis quite long and somewhat twisted; extreme apex extended to a minor, hardly discernible knob; smetimes knob reduced and absent (Figs 348-349).

Female: Apical ventrite lacks lateral knob (Fig. 167). Pro- and mesotarsus slender.

Distribution.

Nigeria, Zaire, Uganda, Tanzania (Fig. 565). Guignot (1955a) gives Rwanda under the name Laccophilus wittei .

Collecting circumstances.

Very little information on ecology is available. Guignot (1955a) reports that Laccophilus burgeoni (under name Laccophilus wittei ) is a rheophil species. Label data from Nigeria indicate that the species has been collected in a muddy running stream with gravel bottom.