Agabus anguluverpus Englund, Njoroge & Bergsten, 2020

Englund, William F., Njoroge, Laban, Bistroem, Olof, Miller, Kelly B., Bilton, David T. & Bergsten, Johannes, 2020, Taxonomic revision of the Afrotropical Agabus raffrayi species group with the description of four new species (Coleoptera, Dytiscidae), ZooKeys 963, pp. 45-79 : 45

publication ID	https://dx.doi.org/10.3897/zookeys.963.53470
publication LSID	lsid:zoobank.org:pub:9636C9F2-C6BD-4B34-BCC6-ED214C7B0D19
persistent identifier	https://treatment.plazi.org/id/78EDD21C-BB25-4472-872C-6159BBAD12E8
taxon LSID	lsid:zoobank.org:act:78EDD21C-BB25-4472-872C-6159BBAD12E8
treatment provided by	ZooKeys by Pensoft
scientific name	Agabus anguluverpus Englund, Njoroge & Bergsten
status	sp. nov.

Treatment

Agabus anguluverpus Englund, Njoroge & Bergsten sp. nov. Figures 1 View Figure 1 , 7A View Figure 7 , 8F View Figure 8 , 10C View Figure 10 , 11K View Figure 11 , 11O View Figure 11 , 12 View Figure 12 , 13 View Figure 13 , 14 View Figure 14 , 20 View Figure 20 , 21 View Figure 21

Type locality.

Kenya, Mount Kenya, Chogoria, Lake Ellis, -0.123N, 37.401E.

Type material.

Holotype ♂ (NMK) labelled: "Kenya, Mt. Kenya, Lake Ellis, Chogoria. - 0.123S 37.401E. 17.IX.2015 Leg. W. Wamiti". Paratypes 1 ♂ 1 ♀ (NHRS, NMK) labelled: "Kenya, Mt. Kenya, Lake Ellis, Chogoria. - 0.123S, 37.401E. 17.IX.2015 Leg. W. Wamiti".

Diagnosis.

This species is in some respects similar to A. sjostedti and A. dytiscoides in that females are matte due to a coarse dorsal microsculpture, and although the pronotal hypomeron is not or barely visible in strict lateral view, the pronotal bead is broader anteriorly (see Fig. 10C View Figure 10 ). The subapical portion of aedeagus is not prolonged, which is similar to South African species of the group, but the apex is straight in ventral view which is unique in the group. The aedeagus is evenly thickened, and essentially lacks the subapical broadening seen in most raffrayi group taxa (see Fig. 8 View Figure 8 ).

Description.

Habitus as in Fig. 11K, O View Figure 11 .

Colour: Head rufopiceous with testaceous interocular spots and an anterior testaceous area. Pronotum brown to rufopiceous with testaceous margins; some specimens with a diffuse rufotestaceous area in the middle of the pronotum. Elytron brown to testaceous brown. Ventral surface rufous, hypomeron testaceous, epipleuron testaceous brown. Legs rufous to testaceous. Antennae and palpi testaceous. The three specimens collected were all teneral individuals, especially the two paratypes, and as a result there is a probability that non-teneral individuals of this species will be somewhat darker than described here. In particular the pronotum may be darker medially in non-teneral individuals.

Microreticulation : Males with medium impressed reticulation on head and pronotum. Females with much coarser and larger meshes than males, giving pronotum and elytra a matte appearance. Both sexes with a mixture of small and somewhat larger meshes.

Structural features : Body length: 7.36-7.52 mm (see Table 1 View Table 1 ). Hypomeron not or barely visible in strict lateral view (see Fig. 10C View Figure 10 ), lateral bead of pronotum broad and well defined, broader anteriorly (see Fig. 10C View Figure 10 ). Metasternal wing narrow, WC/WS 3.0 or more in both males and females (see Table 1 View Table 1 and Fig. 12 View Figure 12 ). Pronotum more than twice as broad as interocular distance (see Table 1 View Table 1 and Fig. 13 View Figure 13 ), lateral margins straighter anteriorly and more curved posteriorly.

Legs: Protarsal claws long,> 1.6 × as long as protarsomere 4 (see Table 2 View Table 2 , Fig. 14 View Figure 14 ). Metatarsomeres very long and slender; metatarsomere 2> 1.8 × as long as broad in both females and males (see Table 2 View Table 2 ), and metatarsomere 5> 3.3 × as long as broad in males (see Table 2 View Table 2 ).

Male genitalia: Aedeagus without distinct subapical broadening and without subapical prolongation; subapical tooth angled both basally and subapically (see Fig. 8F View Figure 8 ). Aedeagus with straight apex in ventral view.

Female: Elytral and pronotal microreticulation much coarser than in males.

Distribution.

Only known from Mount Kenya in central Kenya (see Fig. 1 View Figure 1 ).

Habitat.

Lake Ellis is situated at an altitude of about 3500 m on Mount Kenya’s eastern slope (Figs 20 View Figure 20 , 21 View Figure 21 ).

Etymology.

The species name refers to the angled subapical tooth of the male genitalia (Latin: angulus = angle, verpus = penis).