Catalogue, distribution, taxonomic notes, and conservation of the Western Palearctic endemic hunchback beetles (Tenebrionidae, Misolampus)

Abstract

Hunchback darkling beetles of the Ibero-Maghrebian genus Misolampus Latreille, 1807 (Tenebrionidae, Stenochiinae) encompass six species: M. gibbulus (Herbst, 1799), M. goudotii Guérin-Méneville, 1834, M. lusitanicus Brême, 1842, M. ramburii Brême, 1842, M. scabricollis Graells, 1849, and M. subglaber Rosenhauer, 1856. Previously known distribution ranges of the species were delineated using many old records, the persistence of such populations being questionable under the current situation of global biodiversity loss. Additionally, the status of geographically isolated populations of the genus have been the subject of taxonomic controversy. An exhaustive bibliographical revision and field search was undertaken, and the Misolampus collection of the Museo Nacional de Ciencias Naturales (MNCN-CSIC) was revised. The aims are to (i) provide an updated geographic distribution range for the species of Misolampus; (ii) to determine the taxonomic status of controversial populations; (iii) to provide a catalogue for Misolampus; and (iv) to discuss the conservation status of these saproxylic beetles. As a result, a catalogue including synonymies and type localities, geographical records, diagnoses, and information on natural history for all species of Misolampus is presented. The results reveal that the distribution ranges of the species of Misolampus have not undergone a reduction in the last century, and indicate the presence of the genus in areas where it had never been recorded before. The morphological variability of M. goudotii drove the proposal of different taxa that are here formally synonymised as follows: M. goudotii Guérin-Méneville, 1834 = M. erichsoni Vauloger de Beaupré, 1900, syn. nov. = M. peyerimhoffi Antoine, 1926, syn. nov.

Keywords: Coleoptera; Stenochiinae; geographic range; morphological variability; new synonymies; population persistence; saproxylic; scientific collections.

Figure 1.

Live specimens and habitat of Misolampus gibbulusA–D live adult specimens of Misolampus gibbulus from Portugal (A Foia; B Monchique; D São Martinho das Amoreiras) and Spain (C Santa Helena, Jaén); specimens A, B, and D represent the diversity of sculptural patterns in elytra and pronotum within the Faro population, see the contrast with typical specimen C; E, F typical habitats of M. gibbulus in Spain (E native Quercus ilex and Pinus plantations at Robledo del Mazo, Toledo FQ. ilex open forest with Cytisus and Retama at Puerto de Santa Cruz, Cáceres). Photographs by MGP.

Figure 2.

A Geographic distribution of Misolampus gibbulus. Map of the Iberian Peninsula depicting the geographic distribution range of the Iberian endemic Misolampus gibbulus (orange area). Purple dots correspond to the species’ records, including both recent and old, as well as previously published data B potential geographic distribution of Misolampus gibbulus: Red indicates areas of high suitability, and blue, areas of low suitability. Species distribution model was generated using MaxEnt v 3.4.1 (Elith et al. 2006) and the set of WorldClim v 2.0 (Fick and Hijmans 2017) environmental variables.

Figure 3.

Live specimens and habitat of Misolampus goudotiiA–C Live adult specimens of Misolampus goudotii from the Balearic Islands (A Cap Formentor, Mallorca) and Morocco (B Toufliht, High Atlas C Akarkor, Sidi Ifni); the specimens selected represent the diversity of sculptural patterns in elytra and pronotum reported for the species D–F A summary of the impressive habitat diversity used by M. goudotii from the Balearic Islands (DQuercus ilex forest at Creu de Menut, Mallorca), to southwestern Morocco (E deep valleys in the Toubkal National Park, High Atlas FArgania spinosa open forests at Jbel Toual in Sidi Ifni). Photographs by MGP and NRR.

Figure 4.

A Geographic distribution of Misolampus goudotii. Map for the distribution range of Misolampus goudotii (pale blue spot). Blue dots correspond to the species records, including both recent and old, as well as previously published data. The population from Ifni remains isolated from the main distribution range, by a distance of ca. 250 km B potential geographic distribution of Misolampus goudotii: Red indicates high suitable areas, and blue, areas of low suitability. Species distribution model was generated using MaxEnt v 3.4.1 (Elith et al. 2006) and the set of WorldClim v 2.0 (Fick and Hijmans 2017) environmental variables.

Figure 5

. Live specimens and habitat of Misolampus lusitanicusA–D live specimens of Misolampus lusitanicus from Spain (A, B Fumaces, Ourense C Laguna de La Baña, León) and Portugal (D Fervença-Eido, Porto) E, F two examples of typical habitat of M. lusitanicus from E Sierra de Queixa (Ourense) and F Mountains of Sanabria (Zamora). Photographs by MGP.

Figure 6.

A Geographic distribution of Misolampus lusitanicus. Map depicting the distribution range of the Iberian endemic Misolampus lusitanicus (red spot). Purple dots correspond to the species records, including both recent and old, as well as previously published data B potential geographic distribution of Misolampus lusitanicus: Red indicates areas of high suitability, and blue, areas of low suitability. Species distribution model was generated using MaxEnt v 3.4.1 (Elith et al., 2006) and the set of WorldClim v 2.0 (Fick and Hijmans 2017) environmental variables.

Figure 7.

Live specimens and habitat of Misolampus ramburiiA, B adult Misolampus ramburii from Spain (A Sierra de Gádor, Almería B Sierra de Huétor, Granada); the specimens selected represent the diversity of sculptural patterns in elytra and pronotum, smoother in western populations, without elytral striae (B), marked in eastern areas (A) C, D two examples of typical habitat of M. ramburii from C coastal ravines with scattered Pinus halepensis (Maro, Málaga) and D slope of Sierra Nevada with open forests of Q. ilex and almond trees (Almería). Photographs by MGP.

Figure 8.

A Geographic distribution of Misolampus ramburii. Map of the Iberian Peninsula depicting the geographic distribution of Misolampus ramburii (purple spot), an endemic species to Spain. Blue dots correspond to the species records, including both recent and old, as well as previously published data B potential geographic distribution of Misolampus ramburii: Red indicates areas of high suitability, and blue, areas of low suitability. Species distribution model was generated using MaxEnt v 3.4.1 (Elith et al. 2006) and the set of WorldClim v 2.0 (Fick and Hijmans 2017) environmental variables.

Figure 9.

Live specimens and habitat of Misolampus scabricollisA, B live adult specimens of Misolampus scabricollis from Spain (A Sierra de Guadalupe, Cáceres B Las Honfrías, Montes de Toledo) C–F typical habitats of M. scabricollis (C granitic outcrops with Cytisus, Juniperus communis, and Quercus ilex along the Sistema Central Mountain Chain, Avila D densely reforested area with Pinus sylvestris at Santa Ana, Zamora) EPinus sylvestris forests at the southern slopes of Pico del Lobo, Guadalajara F dense forests of Quercus pyrenaica at Montes de Toledo). Photographs by MGP.

Figure 10.

A Geographic distribution of Misolampus scabricollis. Distribution range of the Iberian endemic Misolampus scabricollis (dark blue spot). Blue dots correspond to the species records, including both recent and old, as well as previously published data. The populations from Huelva (southwestern Spain) remain isolated, since no intermediate populations are known in a distance of at least 150 km, however intervening habitat seems favourable in many areas B potential geographic distribution of Misolampus scabricollis: Red indicates areas of high suitability, and blue, areas of low suitability. Species distribution model was generated using MaxEnt v 3.4.1 (Elith et al. 2006) and the set of WorldClim v 2.0 (Fick and Hijmans 2017) environmental variables.

Figure 11.

Live specimens and habitat of Misolampus subglaberA, B live specimens of Misolampus subglaber from Spain (A Valdeiglesias, Sierra Tejeda, Granada B Miranda del Rey, Sierra Morena, Jaén) C, D general habitat occupied by M. subglaber (C limestone outcrops with Pinus nigra along the Sierra de Alcaraz, Albacete DQuercus suber forests at Cortes de la Frontera, Sierra de Grazalema, Málaga). Photographs by MGP.

Figure 12.

A Geographic distribution of Misolampus subglaber. Distribution range of Misolampus subglaber (green spot). Blue dots correspond to the species records, including both recent and old, as well as previously published data. Cuenca population is isolated from all other known populations by a distance of 150 km. The old bibliographic record from Cartagena (province of Murcia, south western Spain) requires confirmation B potential geographic distribution of Misolampus subglaber: Red indicates high suitable areas, and blue, areas of low suitability. Species distribution model was generated using MaxEnt v 3.4.1 (Elith et al. 2006) and the set of WorldClim v 2.0 (Fick and Hijmans 2017) environmental variables.

Figure 13.

Map of the potential geographic distribution of the Iberian species of Misolampus, with the areas of high suitability (suitability > 0.7) depicted for all the species combined: M. gibbulus (orange), M. lusitanicus (red), M. ramburii (purple), M. scabricollis (dark blue), M. subglaber (green). Dark grey areas correspond to interspecific contact areas. The areas of low suitability for the occurrence of Iberian species of Misolampus are represented in pale grey.

Figure 14.

Lateral view of specimens of MisolampusAMisolampus ramburii from Málaga BMisolampus gibbulus from Santa Elena (Jaén) (MNCN_Ent 270070) CMisolampus subglaber from Cazorla (Jaén) (MNCN_Ent 270037) DMisolampus goudotii from Menorca Island (MNCN_Ent 270032). Note the marked differences in sculpture of elytra among all four species.

Figure 15.

Fronto-dorsal view of specimens of MisolampusAMisolampus gibbulus from Santa Elena (Jaén) (MNCN_Ent 270070) BMisolampus ramburii from Málaga (MNCN_Ent 270037). Note the differences between the two species in the shape of the anterior angles of the prothorax. Scale bars: 1 mm.

Figure 16.

Lateral view of the head and prothorax of specimens of MisolampusAMisolampus scabricollis from Puerto de Navacerrada (Madrid) (MNCN_Ent 270049) BMisolampus subglaber from Cazorla (Jaén) (MNCN_Ent 270209) CMisolampus ramburii from Málaga (MNCN_Ent 270037) DMisolampus gibbulus from Santa Elena (Jaén) (MNCN_Ent 270070) EMisolampus goudotii from Menorca Island (MNCN_Ent 270032) FMisolampus goudotii from Iguermalen, Beni Mesdui (Rif Mountains, Morocco) (MNCN_Ent 270188). Note the marked differences in sculpture and anterior angles of pronotum among all five species represented. Photographs E, F represent some of the geographic variability observed within M. goudotii.

Figure 17.

Fronto-dorsal view of specimens of MisolampusAMisolampus scabricollis from Puerto de Navacerrada (Madrid) (MNCN_Ent 270049) BMisolampus subglaber from Cazorla (Jaén) (MNCN_Ent 270209). Note the differences in the lateral sculpture of pronotum. Scale bars: 1 mm.