Monodaeus tuberculidens (Rathbun, 1911)

Muñoz, Isabel, García-Isarch, Eva & Cuesta, Jose A., 2021, Annotated and updated checklist of marine crabs (Decapoda: Brachyura) of Mozambique supported by morphological and molecular data from shelf and slope species of the “ MOZAMBIQUE ” surveys, Zootaxa 5056 (1), pp. 1-67 : 47

Monodaeus tuberculidens (Rathbun, 1911)

( Figure 14G )

Material examined. M07, Stn. 27, 425m, ♂ 12.2× 8.9mm (IEO-CD-MZ07/1803); M09, Stn. 84, 254m, ♂ 13.6× 9.3mm (IEO-CD-MZ09/1763), 16S ( MZ 424976 ), COI ( MZ 434824 ) .

Habitat and distribution. Its distribution includes Reunion Island, the great bank Saya de Malha, South Africa and Angola, at 210 m ( Guinot & Macpherson 1988), Mayotte Island ( Poupin 2010, 2018), Mozambique ( Emmerson 2016c) and Australia ( GBIF.org 2021, unpublished record).

Results and remarks. The descriptions of Guinot & Macpherson (1988) and Serène (1984) were followed to identify the two male specimens. In one of the specimens (IEO-CD-MZ09/1763) the spines on merus and carpus of P2–P5 are not sharp. Both of them were collected in March ( MZ 07 and MZ09), at depths between 254 and 425m, and thus, these records extend the maximum depth of the species to 425m.

Colouration observed. The carapace was orange with white edges and some small red and white tubercles. Chelae were orange with red tubercule tips, white palm and brown fingers. Meri of chelipeds had orange and white bands and carpi and dactyli were orange with red tubercules.

DNA barcodes. The 16S sequence fits 100% with that of Monodaeus tuberculidens ( HM 798515 ) obtained by Lai et al. (2011). However, it differs in only 1 mutation to two sequences of Monodaeus couchii ( AM 076771 and HM798510 ) by Reuschel & Schubart (2006) and Lai et al. (2011). The COI sequence is also close to one of M. tuberculidens ( HM 751031 ), from the same specimen, also obtained by Lai et al. (2011), fitting 99.66% (two mutations). Similarly to 16S, in this case there are other 20 sequences of M. couchii presenting close haplotypes that vary in a range of five to eight mutations (98.66 to 99.21%). Therefore, M. tuberculidens and M. couchii are closer species that need to be further studied to clarify their relationship.

Figures

FIGURE 14. A, Chaceon macphersoni, ♀ IEO-CD-MZ09/1812; B, Ovalipes iridescens, ♀ IEO-CD-MZ07/1921. C, Scylla serrata, ♀ IEO-CD-MZ08/2238 (preserved); D, Charybdis africana, ♂ IEO-CD-MZ08/1813; E, Charybdis feriata, ♂ IEO-CD- MZ07/1902 (preserved); F, Charybdis smithii, ♂ IEO-CD-MZ08/1813; G, Monodaeus tuberculidens, ♂ IEO-CD-MZ07/1803. Scale bars: 1cm.