Mecistocephalus lohmanderi Verhoeff, 1939

Fig. 11 A

Examined material.

2 specimens: NHMUK 015991459, 1 ♀, Black Path, Picard, Aldabra, Summer 1975, leg. V. W. Spaull; NHMUK 015991460, 1 ♂, Casuarina litter, Picard, 10. 12. 1974, leg. V. W. Spaull.

Remarks.

Originally described from Mauritius (Verhoeff, 1939), M. lohmanderi has been found on other Western Indian Ocean Islands (Bonato and Minelli 2010; Popovici et al. 2024). Similarly to M. angusticeps (Fig. 11 B), examined specimens lack forcipular cerri (Fig. 11 A). Presently examined specimens are most similar to M. lohmanderi specimens collected from the Diego Garcia atoll (Popovici et al. 2024). Adults (female 34 mm body length, male 34 mm body length) in the Aldabra sample lack dark subcutaneous pigment patches and maintain the characteristic clypeal setation pattern described in M. lohmanderi from other localities (Bonato and Minelli 2010; Popovici et al. 2024). Similarly, specimens assigned to M. insularis described from Socotra (Lewis and Wranik 1990) match all diagnostic characters outlined for M. lohmanderi, and can be referred to this taxon, thus extending its range to island localities in the Northwestern Indian Ocean.

Records of large adult specimens (70–91 mm) assigned to Mecistocephalus insularis from the Arabian Peninsula (Lewis 1996) are fully consistent with the revised description of Mecistocephalus glabridorsalis Attems, 1900 from the Seychelles (Bonato and Minelli 2010) and are almost certainly misidentified M. glabridorsalis. In particular, the clypeal morphology illustrated for specimens from Saudi Arabia shares the presence of a small non-areolate insula anterior to the plagulae with specimens from the Seychelles and the arrangement of setae in a transverse line on the areolate part of the clypeus. This morphology has hitherto only been recorded in M. glabridorsalis and M. punctifrons Newport, 1843 (Bonato and Minelli 2004), casting further doubt on the true identity and distribution of M. insularis. Insufficient data on morphological variability in M. lohmanderi and the uncertain status of M. insularis records from past literature prevent further inferences on the taxonomic validity and relationships between these species.