Coelometopon cavifrons Janssens

Perkins, Philip D., 2005, A revision of the African hygropetric genus Coelometopon Janssens, and description of Oomtelecopon new genus (Coleoptera: Hydraenidae), Zootaxa 949 (1), pp. 1-103: 1-103

publication ID 10.11646/zootaxa.949.1.1

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Coelometopon cavifrons Janssens


Coelometopon cavifrons Janssens  

(Figures 49, 50, 86)

Coelometopon cavifrons Janssens, 1972: 390   .

Type Material. Holotype (male): Tanzania, Uluguru Montains, "Morning Side"; deposited in the MRAC. [labels: HOLOTYPUS //Tanzanie: Mts Uluguru Morning Side , alt. 1600 m. 21–29/VI/71 sur roche ruisselante// Coll. Mus. Tervuren Mission Mts Uluguru L. Berger, N. Leleup J. Debecker V /VIII/71// Prép. Micr. No 711012.1// E. Janssens det., 1972 Coelometopon cavifrons   n. sp. //DIGITAL IMAGE captured 2004 P. D. Perkins]  

Diagnosis. Recognized by the contrasting reddish­brown dorsum with piceous elytral punctures, the non­granulate and shining odd­numbered elytral intervals, and, in males, the midlongitudinal ridge on the clypeus (Fig. 49).

Description. Size (length/width, mm x 100) holotype: body (length to elytral apices) 2.50/1.15, head 0.50/0.71, pronotum 0.56/0.96, elytra 1.59/1.15. Head, pronotal disc and elytral serial punctures piceous, remainder of dorsum and legs reddish brown.

Frons with large non­granulate areas, granules near margins, near ocelli and forming midlongitudinal row of about five granules in anterior 1/2; anterior margin markedly concave. Clypeus raised in prominent midlongitudinal ridge; setose at margins; non­granulate except narrowly at base. Granules of frons and pronotum similar in size. Labrum small, set beneath margin of clypeus, lobes small, triangular in ventral aspect. Maxillary palpi small, ca. 3/4 width of anterior margin of clypeus, last three articles subequal in length, last article suboval. Mentum with two depressions.

Pronotum with non­granulate areas on disc; sides straight or weakly arcuate in front of and behind widest part; lateral depressions very wide, strongly granulate at lateral margin, otherwise almost entirely non­granulate, shining; large, deep, oval fovea posteriorly. Median groove deep and wide, tapering slightly posteriorly, margined by sharp, granulate ridge; interior of groove granulate in anterior and posterior depression, shining and nongranulate in middle part; two low, granulate callosities on each side of median groove.

Elytral serial punctures large and deep, very discrete due to color contrast with intervals. Elytral intervals: even numbered intervals with long granulate callosities, all mostly similar in height, 3 on 2nd, 4 on 4th, and ca. 5 on 6th, inter­callosity areas smooth, shining; odd­numbered intervals non­granulate, shining but undulating in part due to deep serial punctures, except 7th with small granulate callosity just behind humeral angle; lateral margin in dorsal aspect formed by granules on raised 8th interval (pseudoepipleuron).

Prosternum with low midlongitudinal carina. Mesosternal process transverse, narrow, anterior face concave. Metasternum strongly carinate behind mesocoxae; midlongitudinal fovea in basal 1/2 narrow, deep; disc on each side of fovea sparsely finely punctate, strongly shining; lateral 1/3 very coarsely densely punctate; posterior margin depressed in front of metacoxae. Abdomen with intercoxal sternite and adjacent part of first ventrite conjointly deeply concave; first ventrite carinate behind metacoxae; intersegmental areas deeply impressed. Females unknown.

Aedeagus length ca. 0.64 mm; flattened and distorted by microslide mounting, hence relationships of parts obscured; distal area enlarged, membranous process spinose, large, expandable; parameres joined near base of mainpiece (right paramere missing on microslide), attaining proximal part of enlarged complex distal area. The drawing I have made is from the underside view of the microslide mount (Fig. 50).

Distribution. Currently known only from the type locality in the Uluguru Mountains of Tanzania (Fig. 86).


Musée Royal de l’Afrique Centrale














Coelometopon cavifrons Janssens

Perkins, Philip D. 2005

Coelometopon cavifrons

Janssens, E. 1972: 390