Ochthebius (Cobalius) cortomaltese, Villastrigo & Hernando & Millán & Ribera, 2020

Villastrigo, Adrian, Hernando, Carles, Millán, Andrés & Ribera, Ignacio, 2020, The neglected diversity of the Ochthebius fauna from Eastern Atlantic and Central and Western Mediterranean coastal rockpools (Coleoptera, Hydraenidae), Organisms Diversity & Evolution (New York, N. Y.) 20 (4), pp. 785-801 : 795

publication ID	https://doi.org/ 10.1007/s13127-020-00463-y
persistent identifier	https://treatment.plazi.org/id/038787F4-8C1B-562D-E9CE-FC0AFBCDF9C8
treatment provided by	Felipe
scientific name	Ochthebius (Cobalius) cortomaltese
status	sp. nov.

Treatment

Ochthebius (Cobalius) cortomaltese View in CoL sp. nov.

Type locality. Maltese archipelago, Island of Malta, Gnejna Bay, 35° 55′ 26.7″ N 14° 20′ 35.9″ E GoogleMaps .

Type material. Holotype female ( NMW): “4 Malta 13.xi.2018 Gnejna Bay /rockpools in Ta’ Lippija / 35° 55′ 26.7″ N 14° 20′ 35.9″ E / A. Villastrigo leg.”, with red holotype and DNA voucher labels. Used for DNA extraction and sequencing ( Table 1), with voucher number IBE-AN1158. Club of left antenna missing. GoogleMaps

Description. Habitus as in Fig. 2b View Fig . Length: 1.58 mm. Body colour black, appendages dark brown.

Upper surface of head ( Fig. 2b View Fig ) very rugose; with dense irregular setiferous punctures with short thick whitish recumbent setae. Frontoclypeal suture shallow, weakly arched; surface of clypeus and labrum less rugose; anterior margin of labrum deeply incised, with a very sparse punctation with very short sparse setae; with two foveae on vertex. Eyes smaller and less prominent than in other species of the group. With an ocellus behind each fovea.

Pronotum ( Fig. 2b View Fig ) trapezoidal, lateral margins straight anteriorly, regularly arched posteriorly; margins very irregularly dented, with broad denticles; surface with well-impressed irregular microreticulation, with a shagreened appearance; with dense, well-impressed irregular setiferous punctures, setae short, erect, hook-like. Anterior angles obtuse, posterior ones rounded; with a very narrow hyaline band at anterior and posterior margins; with two very shallow lateral longitudinal depressions.

Elytra ( Fig. 2b View Fig ) elongate, oval; margins weakly arched, very weakly serrated through their length, with shallow, irregular denticles, more apparent basally. Left elytron broken, glued separately. Surface with regular series of well-impressed setiferous punctures, with short, whitish, robust hook-like recumbent setae; surface between punctures with a microreticulation similar to that on pronotum, with weakly impressed transverse striae. Apterous.

Legs ( Fig. 2b View Fig ) short and robust, with rows of strong, short spine-like setae, without natatorial setae. Left middle leg missing.

Etymology. Named after the comic character Corto Maltese, created by Hugo Pratt in 1967, an adventurous sailor born in Valletta in 1887, son of a sailor from Cornualles and an Andalusian gypsy. Noun in apposition.

Distribution ( Fig. 10 View Fig ). Only known from the type locality.

Habitat. The single specimen was found in small rockpools on sandstone ( Fig. 8c, d View Fig ), together with O. quadricollis (17 exx.) and O. celatus (25 exx.) and larvae of likely these two species. In a subsequent visit in February 2020, the same rockpools were dry. An exhaustive search in the area after inundating them with seawater, washing the shores (including some areas with grasses), and opening rock fissures with a chisel and hammer, did not render any additional specimen.

Remarks. We opted for describing a new species with a single (damaged) female due to the strong genetic dissimilarity with the geographically close O. biltoni (with an estimated divergence of ca.14 Ma) and its placement in the phylogeny as sister to O. evae sp. nov. It did not seem reasonable to wait for the availability of more material due to the rarity of the species: in total, during the two collecting trips to Malta (November 2018 and February 2020), we collected more than 1000 specimens of O. celatus and O. quadricollis , and a single specimen of O. cortomaltese sp. nov. The holotype of O. cortomaltese sp. nov. ( Fig. 2b View Fig ) is very similar to the female paratype of O. biltoni ( Fig. 2a View Fig ), although some differences could be recognised: the shape of the pronotum is clearly rounder and with a narrower base in O. biltoni , the denticulation of the margins of pronotum and elytra more marked, and the series of punctures on the elytra more impressed and with a more rugose appearance. Given the known variability of the species of the group, these differences may be, however, individual rather than specific.