Tuoba sydneyensis (Pocock, 1891 a)

Tuoba sydneyensis (Pocock, 1891 a) View in CoL

Figs 6 View Figure 6 , 7 View Figure 7 , 8 View Figure 8 , 9 View Figure 9 , 10 View Figure 10

Geophilus (Bothrogeophilus) lemuricus Verhoeff, 1939 View in CoL , syn. nov.

Hovanyx waterloti Lawrence, 1960 View in CoL , syn. nov.

Examined material.

19 specimens: NHMUK 015991475 , 1 specimen, South Island , Aldabra, 13–20.03. 1968, leg. B. Cogan & A. Hutson ; NHMUK 015991476 , 1 juvenile, Cinq Cases / Point Hodoul Arga , 27. 03. 1974, leg. V. W. Spaull ; NHMUK 015991477 , 1 ♀, inside fallen dead coconut tree, Picard , Aldabra, 23. 02. 1974, leg. V. W. Spaull ; NHMUK 015991478 , 3 ♀, 1 ♂, 1 juvenile, Cinq Cases , Aldabra, 10–17.03. 1974, leg. V. W. Spaull ; NHMUK 015991479 , 1 ♀, Cyperus ligularis soil and litter, Dune Patates , Aldabra, 05. 06. 1974, leg. V. W. Spaull ; NHMUK 015991480 , 1 ♂, 1 incomplete, Mystroxylon and Dracaena litter, Gionnet , 03. 12. 1974, leg. V. W. Spaull ; NHMUK 015991481 , 1 ♀, 1 ♂, Casuarina litter, Picard , Aldabra, 08. 05. 1974, leg. V. W. Spaull ; NHMUK 015991482 , 1 ♂, Pemphis litter, Dune D’Messe , Grande Terre, 29. 01. 1975, leg. V. W. Spaull ; NHMUK 015991483 , 2 ♂, 1 ♀, Casuarina , Picard, 27. 12. 1974, leg. V. W. Spaull. ; NHMUK 015991484 , 2 ♀, Suriana litter near Point Hodoul , Grande Terre, 22. 03. 1974, leg. V. W. Spaull ; 1 juvenile, Cocos litter, Esprit , Aldabra, 14. 12. 1974, leg. V. W. Spaull .

Remarks.

Tuoba sydneyensis has previously been reported from the Seychelles ( Bonato and Minelli 2010). Material presently described from the Aldabra Atoll, as well as specimens collected on Serpent Island ( Mauritius) and other islands of the Seychelles ( Bonato and Minelli 2010) can be assigned as conspecific on the basis of the low number of leg-bearing segments (41–45), elongation of the antennal articles (Fig. 6 A View Figure 6 ) and in the shape of the ultimate leg-bearing segment metasternite ( Jones 1998).

The only other species of Tuoba hitherto reported from the East African coast are Tuoba poseidonis Verhoeff, 1901 ( Zapparoli 1990) and Tuoba sudanensis Lewis, 1963 . The small number of diagnostic characters separating these two species casts doubt on the validity of T. sudanensis or on the Somali record of T. poseidonis . Examination of additional material from the East African coast would be necessary to elucidate the diversity of Tuoba in Northern and Eastern Africa.

Both species can be reliably differentiated from T. sydneyensis in the Western Indian Ocean by the larger number of leg-bearing segments (51–53 in T. sudanensis compared to 41–45 in T. sydneyensis ), greater elongation of the telopodal lappets of the first maxillae (30 % of the length of the telopodite as illustrated for T. sudanensis ; compared to minute in T. sydneyensis (Fig. 8 B View Figure 8 )), shape of the carpophagus structure (with a distinct median “ hump ” in T. sudanensis ; lacking any “ hump ” medially in T. sydneyensis ), point of the midbody transition (sternites 20–22 in T. poseidonis and T. sudanensis ; sternites 14–15 in T. sydneyensis ) and the shape of the ultimate leg-bearing segment metasternite (1.6 × wider than long as illustrated for male T. sudanensis ; 1.9 × wider than long in male T. sydneyensis , Fig. 10 A View Figure 10 ). The combination of diagnostic characters presented clearly unify the Western Indian Ocean populations of Tuoba under one morphospecies, closely matching the description of T. sydneyensis , which is distinct from Tuoba species recorded in continental Eastern and Northern Africa.

Verhoeff (1939) described Geophilus (Bothrogeophilus) lemuricus from La Ponce, Mauritius and remarked that it is closely related to (“ […] nahe verwandt […] ”) Geophilus carpophagus Leach, 1815 . Although incomplete, the description provides several characters that allow reliable assignment to T. sydneyensis , with which it agrees in number of leg-bearing segments (47 in G. lemuricus , 41–45 in T. sydneyensis from the Western Indian Ocean), the apical claw of the second maxillae being reduced in size and not overtaking surrounding setae in length (“ [...], überragt nicht die Nachbarborsten. ”) (Fig. 8 B, C View Figure 8 ), and in the arrangement of the coxal organs on the coxopleuron of the last leg-bearing segment, which are arranged into a rosette opening in a pouch near the edge of the metasternite (“ [...] neben dem Endbeinsternit mündet eine Tasche und in diese eine Rosette von Drüsen ”) (Figs 9 A View Figure 9 , 10 A View Figure 10 ). We consider G. lemuricus to be a junior subjective synonym of T. sydneyensis , which has been subsequently collected from Mauritius ( NHMUK 015991411 ).