Ikuma spiculosa (Lawrence, 1927)

Zonstein, Sergei & Marusik, Yuri M., 2022, Redescription of the poorly known genus Ikuma Lawrence, with synonymy and description of a new species from Namibia (Araneae, Palpimanidae), African Invertebrates 63 (2), pp. 105-119 : 105

Ikuma spiculosa (Lawrence, 1927)

Fig. 1

Palpimanus spiculosus Lawrence, 1927: 23 (j).

Ikuma spiculosa : Lawrence 1938: 217.

Ikuma squamata Lawrence, 1938: 217, fig. 3 (j), syn. nov.

Types.

Palpimanus spiculosus : Holotype: juvenile, Namibia, Oshikoto Region, Namutoni, 18°48.5'S, 16°56.5'E, 1100 m, unspecified collector, most seemingly G.C. Shortridge (see Thomas 1926), 29.viii.1923 (SAM-ENW-B006293), seen from the full-colour and high-resolution macro-photographs kindly provided by N. Larsen. Ikuma squamata : Holotype: juvenile (or subadult specimen), the same collection data as the preceding but Ikuma (Ekuma) River Valley, approximately 18°34'S, 16°00'E, 1100 m, further details uncertain, presumably deposited in the Transvaal Museum (currently DNMNH); however, it was not found there.

Diagnosis.

There are a number of significant differences between Ikuma spiculosa and I. larseni sp. nov. It concerns the coloration of the abdomen (contrastingly bicolorous vs. uniformly pale), position of the appressed pubescence on the carapace (mostly subcentral vs. sublateral), and the relative length of interdistance AME-AME (longer than AME-ALE vs. shorter than AME-ALE).

Description (based on seemingly non-adult specimens).

The species was in fairly sufficient details described by Lawrence (1927, 1938). See also Fig. 1 .

Distribution.

Oshikoto Region in northern Namibia.

Notes.

The aerial distance between the type localities of Ikuma spiculosa and I. squamata , Namutoni and Ikuma River, is less than 100 km. Both are situated at the same elevation, and they adjoin the same saline depression Etosha Pan. The holotype specimens of the two species do not differ in the peculiarities and details of their pubescence and overall colouration. Judging from the original descriptions, these types can be distinguished only by their size (TL 3.6 in I. spiculosa vs. 5.5 in I. squamata ). Applied to the difference in the body size between these specimens and the type series of I. larseni sp. nov. (TL 10.7-12.1), it may simply indicate that these non-adult specimens can be, respectively, a younger and an elder instars belonging to the same species. Hence, Palpimanus spiculosus Lawrence, 1927 is considered here a senior synonym of Ikuma squamata Lawrence, 1938, syn. nov.

Figures

Figure 1. Ikuma spiculosa, immature holotype specimen SAM-ENW-B 006293 A, B spider in dorsal and lateral view, respectively C carapace, dorsal D body, ventral. Scale bars: 1 mm.