Myoplatypus quadricornis Kirkendall, 2023

Kirkendall, Lawrence R. & Atkinson, Thomas H., 2023, The rare genus Myoplatypus (Coleoptera: Curculionidae: Platypodinae): three new species, new reports, and first records for South America, Zootaxa 5351 (3), pp. 301-321 : 305-310

Myoplatypus quadricornis Kirkendall , new species

( Figs 2 , 5 )

urn:lsid:zoobank.org:act:402F4604-18F9-4A60-BEC4-C551D903D68C

Type material. Holotype male: “ HONDURAS, Olancho, Parq Nac La Muralla , 14 km N La Union, 21 Mar 1995, 15º07’ N, 86º 45’ W, [15.12, -86.75, which is ca 1100 m elevation] en flight intercept trap ”. The holotype is currently in my collection ( LRKC) but will be donated to the NMNH.

Differential diagnosis. Identifiable as a male Myoplatypus by the transverse pair of large spines on ventrite 3 of males and elongate body with a short vertical declivity. The male of the new species is quite similar to males of M. brevicornis (a species currently recorded only from Costa Rica and Panama), and these are the only two species which have small spines on ventrite 4 in addition to the genus-defining large spines on ventrite 3. Myoplatypus quadricornis is more than 1 mm shorter; has interstriae 3 not ending in a prominent horizontal tooth; has the posterolateral angles of the elytra bending more strongly downwards than in M. brevicornis (viewed from the side) but not reaching the level of the sutural apex (viewed from above). The spines on ventrite 4 of M. quadricornis are smaller than those on ventrite 3 but clearly visible; in M. brevicornis males, the spines on ventrite 4 are quite low and not always present.

Similar species. Among Myoplatypus species, only the much larger M. brevicornis has spines on ventrite 4 as well as ventrite 3.

Description of male. Total body length 3.7 mm; net body length (pronotum length plus elytra length) 3.5 mm, 3.4 × as long as wide. Pronotum length 1.2 mm, 1.2 × as long as wide. Elytra length 2.2 mm, 2.2 × as long as wide.

Typical Myoplatypus male in overall appearance. No mycangial pores on pronotum. Anterior margin of the metanepisternal-metaventrite impression with three tiny spines above, one slightly larger spine below. Spines on ventrite 3 large, black-tipped, separated by about 2 × the basal width of a spine. Spines on ventrite 4 black-tipped, prominent but smaller than those on ventrite 3, separated by about 4 × the basal width of a spine. Declivity finely reticulate (dull), short, strongly rounded. Interstriae 3 extending slightly onto declivity, the extension a sharp, low, black carina. Posterolateral margin anterior to angle with three teeth, margin ending in a small posterolateral tooth that does not project beyond the sutural apex. Apical margin of declivity with a small tooth near the suture on each elytron.

Distribution. Known only from the locality of the Honduran holotype. Elevations in the La Muralla National Refuge range from 800 to nearly 2100 m (https://asidehonduras.org/la-muralla/): similar to M. brevicornis , the new species has been collected from middle elevation forests.

Biology. Unknown other than that one specimen was taken from a middle elevation tropical forest.

Etymology. The species epithet highlights the presence of four prominent spines on the venter, where two such spines is the norm for the genus. Adjective.

Figures

FIGURE 2. Dorsal, lateral, and angled posterior views of the declivities of four species of Myoplatypus. (A–C) M. biprorus. (D–F) M. prenexus. (G–I) M. connexus. (J–L) M. senexus. For sources of photos, see plates for the respective species; for sizes of species, see Table 1.

FIGURE 5. Myoplatypus quadricornis Kirkendall, male holotype. (A) dorsal view. (B) Lateral view; medium-sized spines on ventrite 3 can be readily seen, but those on ventrite 4 cannot. (C) Frontal view. (D) Posterior view, showing declivity; the large, backward-pointing spines originating on ventrite 3 are visible. (E) Venter, showing form and position of the large spines on ventrite 3 and the much smaller spines on ventrite 4. Photos by T.H. Atkinson.