Mastigus glabratus Klug, 1824 : 166

Jałoszyński, Paweł, 2012, New synonymy and redescription of Mastigus deustus (Thunberg) (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 3482, pp. 68-76 : 71-72

Mastigus glabratus Klug, 1824: 166 .

In 1824, Klug described two species of Mastigus : M. fuscus and M. glabratus . Leleup (1968) believed that the types of both these species were missing from the historical collection of MNHUB, which holds specimens belonging to the collection of Johann Christoph Friedrich Klug. Therefore, he treated these taxa as incertae sedis within Mastigini. In fact, two specimens that may belong to the type series of either M. glabratus or M. fuscus can be found in MNHUB, but none of them bears an identification label with one of these names.

Descriptions of M. glabratus and M. fuscus were based on specimens collected by Ludwig Krebs in "Promontorium bonae spei", i.e. the Cape of Good Hope, South Africa (at that time this name was used for the entire Cape Region). The type locality for both species given by Klug (1824) is "Distr. Uitenhagen", i.e. the town Uitenhage in the Eastern Cape Province, near Port Elizabeth. The catalogue of the historical collection of MNHUB includes only two entries for Mastigus which refer to South Africa: record #5111: " Mastigus spec., 4 specimens from Promont. b. sp., Krebs", and record #5112: " Mastigus luridipennis Boh. , 1 specimen from Port Natal, Boheman" (B. Jaeger, pers. comm.). Presently, only two specimens of Mastigus possibly representing both records are preserved at MNHUB. One is a male bearing a large blue-greenish label (originally placed in a drawer, later pinned under the specimen) ( Figs. 5–7 ) that unambiguously identifies the specimen as coming from the Cape collection of Krebs, so this is a type specimen belonging to the record #5111. The other one is a female labeled as M. luridipennis Boheman (unpublished name), and therefore it is the specimen belonging to the catalogue record # 5112. These two specimens were examined in 1973 by Bordoni and Castellini, labeled as the holotype (#5111) and paratype (#5112) of M. glabratus (label data) and the male was used to illustrate the aedeagus of M. glabratus . However, the specimen #5112 (" M. luridipennis ") certainly is not a type specimen, for the following reasons: i) it was collected in Port Natal, a locality distant from the Cape region; ii) it did not belong to the Krebs Coll. but it was acquired from Boheman. Therefore, this female is neither a paratype nor a syntype of M. glabratus . In contrast, the label data of the male specimen #5111 match those given in the Klug's original article, and it is either the type of M. glabratus or M. fuscus . Since the number of specimens seen by Klug was not specified, this specimen has a status of a syntype, and not holotype.

A problem that remained to be solved was whether the syntype male specimen #5111 is M. glabratus or M. fuscus . This question can be answered on the basis of the Klug's original descriptions of these species. Mastigus glabratus was described as having the venter of thorax brown and abdominal sternites brown, darkened in middle ("Brust und Bauch sind braun, letzterer in der Mitte dunkler"), while M. fuscus as having the venter of thorax and abdomen blackish ("Brust und Bauch sind schwärzlich"). This information is sufficient to identify the specimen #5111 as a syntype of M. glabratus , as having the meso- and metaventrite brown and the abdomen with similarly brown margins, gradually darkened towards middle. In order to preserve stability of nomenclature and to fix a unique bearer of the name Mastigus glabratus , this syntype is here designated a lectotype.

Bordoni & Castellini (1973) redescribed M. glabratus as distinct from M. deustus . In fact, both the lectotype of M. glabratus and the female labeled as " M. luridipennis " are conspecific with the syntype of M. deustus from the Thunberg Coll. (UUZM), which confirms earlier Leleup's identifications made in 1974 (label data). The source of this misidentification was most likely the Klug's statement that M. glabratus differs from M. deustus , and the illustrations of the aedeagus of M. deustus given by Leleup (1968; Figs. 37–38), showing a copulatory organ clearly different from that figured by Bordoni & Castellini (1973) for M. glabratus .

Mastigus glabratus was described by Klug (1824) as similar to M. deustus , but differing in proportions of antennomeres ("scheint in dem Verhältnis der Fühler ein Untershied vorhanden zu seyn") and in the presence of distinct rows of punctures on the elytra. Klug based the latter difference on the Thunberg's description ("absque punctis et striis", i.e. without punctures and striae). However, the female syntype of Notoxus deustus from the Thunberg Coll. (here designated lectotype) has indistinct longitudinal rows of small punctures on the elytra. The proportions of antennomeres in the incomplete antenna preserved in the lectotype of M. deustus are inconclusive. The male specimen dissected by Leleup (preserved at MZLU) and used to illustrate the aedeagus in his 1968 paper was identified correctly as M. deustus , but it is a teneral beetle and its aedeagus is not fully sclerotized and deformed. This specimen (identifiable on the basis of the label “allotypus” and location label data given in Leleup, 1968), is conspecific with M. glabratus . Mastigus glabratus is here placed as a junior objective synonym of M. deustus .

Figures

FIGURES 1 – 7. Mastigus deustus (Thunberg). Lectotype female of M. deustus in dorsal (1) and lateral (2) views; microscope slide of antenna and maxillary palp of the lectotype female of M. deustus (3); labels of the lectotype female of M. deustus (4). Lectotype male of M. glabratus Klug in dorsal (5) and lateral (6) views; labels of the lectotype male of M. glabratus (7). Scale bars: 2 mm.