Tenupedunculus Schultz, 1982

Serov, Peter A. & Wilson, George D. F., 1995, A review of the Stenetriidae (Crustacea: Isopoda: Asellota), Records of the Australian Museum 47 (1), pp. 39-82 : 77

Tenupedunculus Schultz, 1982

Figs 2G,H , 3H

Tenupedunculus Schultz, 1982: 54-58 , figs 30-31.

Type species. Tenupedunculus elongatus Schultz, 1982

Species included. See Table 1 .

Diagnosis. Head angular, broader than long with elongate, acutely pointed lateral spines extending past rostrum. Rostrum small rounded, extending slightly past antennal spine. Eyes reniform of about 20 ocelli. Antennal article 1 without lateral spine. Antennular flagellum with 12-24 articles. Pereonites 1-4 with sharply produced anterolateral corners, double coxal lobes visible in dorsal view. Male pleopod 11 protopod with small, pointed apical extension; appendix masculina elongate, narrow, distal tip rounded laterally but weakly pointed on medial margin with subdistal lateral setal ridge; exopod and endopod subapical on medial margin. Female pleopod 11 with distal half narrowing sharply to rounded point. Pleotelson with 2 free pleonites. Pleotelson with weak posterolateral spines, prominent posterolateral and medial cuticular extensions. Uropods large.

Remarks. The unifying features of Tenupedunculus include the shape of the male pleopod I, the appendix masculina of pleopod 11, the number of dorsally visible coxal lobes, and a head with large, robust lateral spines and reduced antennal spines. The degree of enlargement of the lateral spine and reduction of the antennal spine varies throughout the genus from the extreme cases as seen in Stenetrium acutum and Stenetrium inflectifrons to the more subdued forms of Stenetrium pulchrum and Stenetrium drakensis (nee Protallocoxa ) S. drakensis was placed in this genus, even though no males were collected, because of its close resemblance with Stenetrium beddardi in the cephalon armature, the pleotelson shape and the presence of 2 coxal lobes on pereonite I. Schultz (1982) also noted a close resemblance between these two species.

The concept of Tenupedunculus Schultz, 1982 was based on lack of eyes in T. elongatus , a dubious diagnostic feature (cf. Wolff, 1962; Hessler & Wilson, 1983). All other features used in Schultz's (1982) description do not unequivocally define the new genus among all stenetriids. Schultz (1982) even states that the "male pleopod 2 and others [are] Stenetrium like". The similarities to Stenetrium pulchrum and Stenetrium haswelli in the male pleopods, the pleotelson and the dorsally visible coxal lobes of T. elongatus , however, place this species within this genus. Although T. elongatus does not represent the typical form of this genus as seen in S. acutum and S. inflectifrons , the genus name is valid and has priority. Therefore Tenupedunculus is used as the name for this genus. Tenupedunculus may be further separated into two groups after closer examination of the types.

Figures

Fig. 2. Stenetriid genera showing body form and male pleopod H. A,B, Mizothenar n.gen. (after Kensley, 1984a, figs 33a, 34b). C,D, Protallocoxa Schultz (after Wolff, 1962, figs la, 5b). E,F, Stenobermuda Schultz (after Schultz, 1979b, figs 1, 3). G,H, Tenupedunculus Schultz (after Schultz, 1982, fig. 20a,c).

Fig. 3. Male pereopod I variation among stenetriid genera. A, Stenetrium Haswell. B, Tristenium n.gen. (after Miiller, 1991c, fig. 10). C, Hansenium n.gen. (after Kensley, 1984a, fig. 37b). D, Liocoryphe n.gen. (after Kensley, 1984a, fig. 32). E, Mizothenar n.gen. (after Kensley, 1984a, fig. 33h). F, Protallocoxa Schultz (after Wolff, 1962, fig. 4a). G, Stenobermuda Schultz (after Kensley, 1994, fig. 9a). H, Tenupedunculus Schultz (after Schultz, 1982, fig. 22a).