Eulimnadia alluaudi Daday de Deés, 1926

Rabet, Nicolas, 2010, Revision of the egg morphology of Eulimnadia (Crustacea, Branchiopoda, Spinicaudata), Zoosystema 32 (3), pp. 373-391 : 377-378

Eulimnadia alluaudi Daday de Deés, 1926

( Fig. 2 A-D)

Eulimnadia alluaudi Daday de Deés, 1926: 567 , fig. 144.

Limnadia alluaudi – Brtek 1997: 56.

TYPE LOCALITY. — Daday de Deés (1926) reported two localities for this species. The first locality is considered as the type locality, and that sample was studied here (south of Madagascar in Bekitro commune). The other locality is from Topani, between Sekuma in Kalahari state, collected by L. Schultze the 4 November 1897 (Bostwana). It is possible that each population represents a separate species.

MATERIAL EXAMINED. — Madagascar. Manambahy, Bekitro, 1901, Ch. Alluaud,> 100 eggs (MNHN-Bp319)

RANGE. — The present knowledge of egg morphology suggests this species is restricted to the type locality as defined above, in the south of Madagascar. The other population, in southern Africa, needs to be investigated.

EGG MORPHOLOGY

The eggs, collected in the bottom of the bottle and in position below the carapace, have a more or less cylindrical structure with a wider, very inflated side creating a pentagonal shape, though in some orientations the eggs seem to be spherical (compare eggs in Fig. 2A and Fig. 2B with Fig. 2C ). The furrows covering the main cylindrical part of the egg are parallel, but on the inflated side the furrows are randomly distributed. The furrow bottoms are narrow, while the ridges are large and round.In detail, the surface bears very small pores ( Fig. 2D ). Average egg height is 175 µm (n = 3, SD = 7.9 µm).

REMARKS

Following Daday de Deés (1926), the egg of this species was firstly described as “Ova membrana tuberculata tecta”. The drawings suggest that the egg is spherical and ornamented by numerous peaks, which is not exactly compatible with the egg described here. However, the examined eggs were in natural position and clustered, thus excluding contaminations. Pentagonal eggs are also known in E. geayi (see Martin 1989; Pereira & Garcia 2001 and this study) though in E. alluaudi the inflated side seems to be more inflated than in E. geayi thus presenting an outline more spherical than cylindrical. In addition the two species are distinct because in E. geayi the bottom of furrows seems to be larger and the ridges sharper, and not rounded as in E. alluaudi . Among typical E. alluaudi eggs, I found in the bottom of the bottle, one spherical egg identical to those described for E. chaperi ; I interpreted it as a contaminant.

Figures

FIG. 2.— Eggs morphology:A-D, Eulimnadia alluaudi Daday de Deés,1926,eggs from the type specimen;E-I, Eulimnadia chaperi (Simon, 1886), eggs from the type specimen; E, immature egg; F-I, mature eggs. Scale bars: A-C, E, F, 100 μm; D, G, H, 20 μm; I, 5 μm.