Siphonorhinus sp.

Wesener, Thomas, 2014, First records of the order Siphonophorida from Madagascar and Mauritius (Diplopoda), Revue suisse de Zoologie 121 (3), pp. 415-423 : 417

Siphonorhinus sp.

Fig. 1

MATERIAL EXAMINED: MHNG Mad 89/21; 3 ♂, 2 ♀; Madagascar, Province Antananarivo, Ankaratra massif , Station Forestière Manjakatompo , près du sommet du Anosirivo, forêt primaire, prélèvement de sol dans une vieille souche, 1980 m; 26.xi.1989, leg. B. Hauser, extraction Berlese à Genève.

HABITAT: The forest of Manjakatompo is one of the three last (99% has been destroyed) indigenous high plateau forests on Madagascar. It was planted by humans a few centuries ago, when it was still connected to now no longer existing fragments of pristine highland vegetation. It harbours rare and endemic genera and species of mammals, but lacks other faunal elements (such as lemurs) most likely due to the artificial origin of the forest and the lack of any fruit-bearing trees ( Goodman et al., 1996).

REMARKS: Largest specimen (male) about 11 mm long, 0.7 mm wide, with 61+1 segments. Colouration whitish orange ( Fig. 1A ). Only specimens of this species could be studied in more detail. While the author refrains from a formal description, the illustrated characters can be compared with those of properly revised species ( Shelley & Hoffman, 2004; Marek et al., 2012) to allow a revision of the family in the future. This species is only tentatively placed in the genus Siphonorhinus Pocock, 1894 , whose eight species occur in Indonesia, Vietnam, Cambodia, Laos and India ( Jeekel, 2001). Siphonorhinus is characterized by an unmodified first leg in males where the coxa is fused to the sternite or stigmatic plate ( Fig. 1B ), by a pear-shaped head ( Fig. 1C ), and by the apical podomere of the posterior gonopod being divided into two branches lacking spines ( Fig. 1D ). In the South African genus Nematozonium Verhoeff, 1939 the posterior gonopods are different, with one of the branches wrapped around the second branch and with each of the branches carrying a spine ( Shelley & Hoffman, 2004). The species of the other Asian genus, Kleruchus Attems, 1938 (originally assigned to the order Platydesmida ), are much larger and wider, and feature thick modified first legs in males. The fourth genus, Illacme Cook & Loomis 1928 , is known only from California, USA. It resembles the shorter species presented here, and features different, apically serrated posterior gonopods (compare Fig. 1D to Marek et al., 2012: fig. 6a).

Figures

FIG. 1 Siphonorhinus sp., MHNG Mad 89/21, two males, A = smaller male specimen, B-D = largest male specimen, multi-layer photograph and SEM. (A) Habitus, lateral view. (B) First and second legs, anterior view. (C) Head, lateral view. (D) Posterior gonopods and leg pair 10, anterior view. Abbreviations: L1 = leg 1; L2 = leg 2; L10 = leg 10; pG = posterior gonopod (= leg 9); St = sternite fused to stigmatic plate.