Crenoicus mixtus Nicholls, 1944

Wilson, George D. F. & Ho, L. E., 1996, Crenoicus Nicholls, 1944 (Crustacea, Isopoda, Phreactoicidea): Systematics and biology of a new species from New South Wales, Records of the Australian Museum 48 (1), pp. 7-32 : 10-12

Crenoicus mixtus Nicholls, 1944

Crenoicus mixtus Nicholls, 1944: 23-27 , figs 38-39.

Syntypes. Types not examined, apparently lost (Poore et aI., in press). Nicholls (1944) reported 1 male bl (body length) 14 mm, 6 females and 23 other specimens that he used for his description.

Type locality. "On Dividing Range near Ballarat [Victoria], in springs and soaks at the source of that city's water supply" ( Nicholls, 1944: 27). Assuming that Winter Swamp near Ballarat is the type locality, this locality might be 37°33'S 143°48'E .

Diagnosis (derived from Nicholls, 1944: figs 38-39). Posterior robust seta on ventral margin of pleotelson subequal or shorter. than more anterior robust seta. Maxillipedal epipod distally rounded. Male pereopod I basis anteroproximal surface with less than 5 setae, lacking dense group of setae. Male pereopod IV propodus not dorsally expanded, distal width less than palm length, anterior surface with distal indentation; ischium posterodistal margin with approximately 10 long setae. Pleopod I exopod proximally concave, widest point approximately midlength. Pleopod 11 appendix masculina with smooth tapering shaft, distal tip pointed (detail unknown, possibly with seta vis. Nicholls, 1944: fig. 39,13.2); endopod distally rounded, lacking indentation; distal segment of exopod longer than wide, lateral margin proximally straight sided.

Remarks. This diagnosis remains preliminary because we did not examine the types, which have been lost, depending only on Nicholls' description and illustrations. Some character states in the diagnosis depend on the accuracy of Nicholls' drawings. In most cases, we have found his rendition of shapes to be accurate, but setal details may be more fallible. Although Nicholls writes that penialstylet,unarmedterminally... ( Nicholls, 1944: 27), he illustrates it with a small distal split, suggesting that the stylet may have a seta as in other Crenoicus species. In any case, a pointed tip of the appendix masculina is a putative synapomorphy of the genus.