Notomicrus meizon species group

Baca, Stephen M. & Short, Andrew Edward Z., 2021, Review of the New World Notomicrus Sharp (Coleoptera, Noteridae) I: Circumscription of species groups and review of the josiahi group with description of a new species from Brazil, ZooKeys 1025, pp. 177-201 : 177

3. Notomicrus meizon species group

Diagnosis.

Non-teneral specimens of this group tend to have the following combination of characters: (1) triangular pigmented area medially on the base of the elytra (Fig. 1g-i ), similar to N. josiahi , but not as prominent and not always discernible in some populations or in teneral specimens; (2) dense, fine punctures bearing short setae on the posterior half of the elytra and sometimes extending far anteriorly (not as coarse as in members of the Notomicrus traili group); (3) microreticulation variably impressed, consisting of fine mesh-like reticulation; often iridescent; (4) posterior lobes of noterid platform with squared or rounded angles (Fig. 4e ); if posterior angles of noterid platform more acute (Fig. 4f, g ), protibia presents robust seta of outer margin approximately at half-length of outer margin, distance between robust seta and dorsoapical angle subequal to distance between robust seta and first seta from protibial insertion (Fig. 2d ).

Composition.

N. malkini Young, 1978; N. meizon Guimarães & Ferreira-Jr, 2019.

Identification resources.

Young (1978); Guimarães and Ferreira-Jr (2019).

Remarks.

The Notomicrus meizon group is sometimes difficult to discern from the Notomicrus traili group, as the differences amongst diagnostic characters can be subtle. The darkened basal area of the elytra in the Notomicrus meizon group is helpful, but investigators may find great difficulty in diagnosing teneral members of this group, which often lack the pigmented triangular area on the elytra. It is important to note that this darkened area is truly pigmented, not just darker in appearance due to the folding of the wings under the elytra as often happens in lighter colored species (as in Fig. 1f, j, k ). Fortunately, males of most individual species of the Notomicrus meizon group are easy to identify by their aedeagi in combination with other characters, such as tarsal claws. The male median lobes of the Notomicrus meizon group species are usually (but not always) very irregularly shaped (for example, see Young 1978 and Guimarães and Ferreira-Jr 2019). The aedeagus of most species of the Notomicrus traili group appear similar to Fig. 8 , with a small club at apex, often hooked to the left (see Young 1978; Manuel 2015; Baca and Short 2018). Additionally, males of Notomicrus meizon species often present notable unequal lengths between the anterior and posterior protarsal claws. These are usually subequal in length in the Notomicrus traili group.

Figures

Figure 1. Notomicrus species groups. Dorsal habitus of representative Notomicrus species a N. nanulus b N. sharpi c N. sp. d N. cf. traili e N. cf. gracilipes f N. petrareptans g N. sp. h N. sp nr. malkini i N. sp. nr. meizon j N. tenellus k N. brevicornis male syntype.

Figure 2. Representative prolegs of Notomicrus species groups (left proleg, anterior aspect) a Notomicrus josiahi group (N. josiahi) b Notomicrus nanulus group (N. nanulus) c Notomicrus meizon group (Notomicrus sp.) d Notomicrus meizon group, alternative setal spacing of dorsal (outer) protibial margin (Notomicrus sp.) e Notomicrus traili group (N. cf. traili) f detail of structures of importance. F 1 Se = setae of anteroventral margin of profemur; F 1 Sp = protuberance of posteroventral margin of profemur; PtCA = anterior protarsal claw; Ptm- 5 = protarsomere V; SeDA = first robust seta of dorsoapical angle; SeMl = robust seta at mid-length of anterodorsal margin of protibia; SeM = First seta of anterodorsal margin of protibia; arrows indicate points for relative lengths (see key): i = anteroapical angle, ii = robust seta at mid-length, iii = first seta of marginal row.

Figure 4. Representative noterid platforms of Notomicrus species groups (left side, ventral aspect). Names in boxes indicate species groups or species a N. josiahi b N. nanulus c N. sharpi d N. sp. (Notomicrus nr. chailliei) e N. sp. nr. meizon f N. meizon (paratype) g N. sp. nr. malkini h N. brevicornis (female syntype) i N. teramnus (female paratype) j N. tenellus (Indonesia) k N. sabrouxi (female paratype, sketched from Manuel (2015: 518) l N. petrareptans.

Figures 8, 9. Pro- and mesotarsal claws of Notomicrus josiahi species group 8 N. josiahi 9 N. interstinctus sp. nov. a anterior protarsal claw b posterior protarsal claw c anterior mesotarsal claw d posterior mesotarsal claw. All anterior aspect. Scale bars: 25 µm.