Leydigia (Neoleydigia) ciliata Gauthier, 1939

Kotov, Alexey A., 2009, A revision of Leydigia Kurz, 1875 (Anomopoda, Cladocera, Branchiopoda), and subgeneric differentiation within the genus, Zootaxa 2082 (1), pp. 1-84 : 68-70

XI. Leydigia (Neoleydigia) ciliata Gauthier, 1939

' Leydigia mixta Sars', unpublished material.

Leydigia propinqua Sars, 1903, p. 14 , Pl. 1: figs 4, 4a (only material from Sumatra); Jenkin 1934: 285; Chiang Sieh-chin and Du Nan-shan 1979, p. 209–210, fig. 140.

Leydigia propinqua var. ciliata Gauthier, 1939, p. 168 –173, fig. 9.

Leydigia propinqua ciliata Gauthier in Dumont and Van de Velde 1977, p. 90 –91, figs 8–9; Van de Velde 1978, p. 195; Dumont 1981, p. 99; Dumont et al. 1981, p. 165; Dumont 1986, Tab. 1.

Leydigia ciliata Gauthier in Rey and Sain-Jean 1968, p. 105, fig. 21; Smirnov 1971, p. 454 –458, figs 562, 564–565 (part); Dumont et al. 1984, p. 167, figs 1–5; Venkataraman and Krishnaswamy 1984, p. 1097 –1098, figs 1–3; Venkataraman 1990a, p. 38, 1990b, p. 116, Pl. 7: figs 38–43; Yoon and Kim 1993, p. 385 –389, figs 3–4; Tanaka 1989, p. 4 –5, Pl. 11: figs 11–12; Kotov et al. 2003b, p. 180 –190, figs 1–63.

Leydigia acanthocercoides (Fischer) in Daday 1910, p. 137; Chiang Sieh-chin and Du Nan-shan 1979, p. 208–209, fig. 139A–F; Biswas 1971, p. 129, fig. 12F; Alam and Khan 1998, p. 143–144, fig. 1A–C.

Leydigia ankammaraoi Prasad, Santa Kumari et Bose, 1986, p. 99 –107, figs 1–15.

Leydigia macrodonta macrodonta Sars in Jeje 1988, p. 113 -116, figs 1-8.

? Leydigia hardingi Nayar, 1971, p. 516 , figs 49–51.

Not L. ciliata Gauthier in Harding 1955, p. 342–343, figs 50–60; Shen Chia-jui at al. 1964, p. 218–220, figs 28–34; Chiang Sieh-chin and Du Nan-shan 1979, p. 211–212, fig. 142A–G; Infante 1980, p. 600: fig. 8; Battish 1981, p. 24, figs 16–22; Valdivia Villar 1985, p. Tab. 2, fig. 6; Chen Shou-zhong 1993, p. 14; Elmoor-Loureiro 1998, p. 35; Elmoor-Loureiro 2000, Tab. 1.

Type locality. "Abéché et Oum Hadjer", (appr. 13°18'N, 19° 40'E), northern Chad. Previous authors ( Smirnov 1971; Dumont et al. 1984) said that this locality is in the region of Lake Chad, but, in reality, it is relatively far from that lake.

Type material. Gauthier's collection was confiscated by the Algerian government. There has been no subsequent information about the whereabouts of this collection, but it is almost certainly lost ( Hudec 1993).

Material examined earlier. See Kotov et al., (2003b) for list of material from Yemen, Mali, Niger, Mauritania, Tanzania; Kenya.

Additional material examined here. Australia. New South Wales: Maitland Power Station Res., via Maitland coll. 23.04.1967 by B. V. Timms , tube NNS 1998-158 ; Warrah Creek at Old Warrah , basin of the Namoi River coll. by DLWC, tube DLWC 5250 a . Indonesia. Sumatra, tube GOS F 12276 (unpublished ' Leydigia mixta ') . Japan. A small artificial pond near Toyama University coll. 02.11.2002 by S. Tanaka, tube AAK 2002-117l Lake Nukikawa-naiko near L. Biwa coll. 06.08.2001 by M. Nishino and A. Ohtaka , tube AAK 2002-018 . Thailand. Chaiyaphum Province: a rice field, coll. 10.04.1999 by L. Sanoamuang, tube AAK 2003-041 ; Uttaradit Province: a puddle near village Chai-Mongkon, left side of highway Phitsanulok- Uttaradit less than 1 km N from deviation to Tron, Tron District, coll. 04.04.2003 by A. A. Kotov, tube AAK 2003-052 ; Phitsanulok Province: A channel, left side of hw Phitsanulok-Uttaradit near km.14, Muang District, coll. 04.04.2003 by A. A. Kotov, tube AAK 2003-055 ; canal in Muang District, coll. 29.09.1996 by L. Sanoamuang , tube AAK 2003-065 ; Kalasin Province: a roadside canal, coll. 04.07.1993 by L. Sanoamuang, tube AAK 2003-064 ; Khon Kaen Province: an un-named temporary pond in Ban Non Muang subdistrics, appr. 2 km from Khon Kaen University campus, coll. 07.06.1998 by L. Sanoamuang, tubes AAK 2003-066 and AAK 2003-067 ; Nam Un Reservoir, coll. 09.05.1998 by L. Sanoamuang , tube AAK 2003-057 .

India. Ricefield Mutluru , coll. 27.11.1983 by T. Ankamma Rao, slide and tube NHM 1984.214 . and NHM 1984.215 . (holotype and paratype of L. ankammaraoi ); Lake Chilika, coll. 20.11.2000 by B. Scharf, tube AAK 2001-035 . Iraq. Basrah , coll. N. N. Smirnov, tube AAK 2003-016 . Kazakhstan. Aktiubinsk Area : Lake Karman-Kul', coll. 15.08.1965, slides NNS MGU 1977 , 2041 . Seychelles. Loc. 26, Aldabra atoll, 1.100 km SE of Mahé Island, coll. 27.01.1968 by K. G. McKenzie, tube NHM 1969.6 .9.582 .

Diagnosis. Parthenogenetic female. Body subovoid, maximum height in posterior half, dorsal margin slightly curved to almost straight in posterior part, postero-dorsal angle rounded, although distinct, in anterior view body subovoid, somewhat compressed laterally, without dorsal keel. Coarse striation observable to varying degree, but small-scale striation always distinct. Eye smaller than ocellus, but size of ocellus variable. Head shield wide, PP = 4–5 IP, lateral head pores at level of central major pore 0.2–0.3 IP from midline. Labral keel wide, triangular-round, its posterior margin with 3 groups of small setules, anterior margin with fringe of long setules, which reach the apex, setules in lateral groups as long as marginal setules. In middle of ventral margin, setae with short setulation, long setules between their bases. In postero-ventral region, these setae setulated asymmetrically. Posteriorly to the last marginal seta, robust setules in successive pectens. On inner side of carapace, a row of small setules at some distance from posterior margin of valve, marginal membrane with minute 'setules'.

Postabdomen relatively broad, but narrower than in L. acanthocercoides , maximum width in middle, ventral margin almost straight. Preanal margin somewhat shorter than anus, with 3–4 distinct hillocks, preanal angle well defined, postanal angle less distinct but present. Postanal margin regularly curved, dorso-distal angle absent. Postanal marginal denticles in successive series of 3–5 denticles, with size increasing distally in each series, 8–10 fascicles of long lateral setae, decreasing in size basally, 3–4 setae in each fascicle, marginal setae of each fascicle longest,ventralmost setae frequently rudimentary. Distal segment of postabdominal seta with dense setules. Postabdominal claw shorter than preanal plus anal portions of postabdomen, basal spine as smoothed hillock or rudimentary.

Antenna I not reaching tip of rostrum, with 4 transverse rows of long setules on anterior face, and series of setules at tip. Sensory seta half as long as appendage, arising 1/3 of way from tip. Antenna II with 3 (rarely 4) spine-like setules on first and second endopod segments. No chitinous insertions within distal segments of swimming setae.

Trunk limb I with ODL large, with long seta, distal segment unilaterally densely setulated. IDL with 3 medial and 3 marginal clusters of setules, in basalmost marginal cluster setules long, in two others mediumsized. On endite 3 seta 1 densely setulated, on endite 2 setae e and f of subequal size. Trunk limb II with small exopodite armed with short setules apically, scraper 1 with naked basal segment and unilaterally, setulated by long setules, distal segment, located on distal lobe with basal group of long setules and distal tuft of short setules. Trunk limb III exopodite seta 1 with distal segment bilaterally setulated, and basal segment unilaterally setulated, seta 2 with short setules of different size on distal segment, and rudimentary seta 3. Trunk limb IV exopodite with seta 2 and, especially 1, short, with long setules distally, all setae of filter plate with inflated tips. On inner side of limb, two setulated setae of subequal length.

Ephippial female. Unknown.

Adult male. Not described to recent standards. According to Dumont and Van de Velde (1977, p. 90–91, figs 8–9), postabdomen elongated, preanal margin with numerous low hillocks, penis thick, longer than half length of claw, without stylet at tip. Antenna I as in male of L. acanthocercoides .

Size. Parthenogenetic females 550–1110 µm.

Full redescription. See Kotov et al. (2003b).

Differential diagnosis. L. ciliata is closest to L. acanthocercoides , type species of the genus, but differs from the latter in its widely rounded posterior portion of the head shield, more narrow postabdomen and three setae in each lateral fascicle on the postabdomen, and sculpture of the ephippium.

Taxonomical comments. Sars (1903) found this species in Sumatra (see chapter on propinqua ). This material is present in GOS under Sars' provisional name ' L. mixta Sars'. But the author did not appreciate that his populations from Sumatra and South Africa belong to different species. L. ciliata was described as a variety of L. propinqua , although authors of the 20th century doubted this. It is clear now that these two species are distant relatives.

The description of Gauthier (1939) appears detailed at first sight but in reality, no character helpful for the discrimination of L. ciliata from L. acanthocercoides is reported. Confusion in the understanding of different species of the acanthocercoides -group resulted in numerous determinations of L. ciliata under other names (see synonymy). Examination of African populations leads to the conclusion that there is only a single species from the acanthocercoides -group here, namely L. ciliata ( Kotov et al. 2003b) , but there is a possibility that L. acanthocercoides may be found in the Mediterranean region, north of the Sahara. In the course of the present revision I found populations similar to L. ciliata in Australia, though this species is not frequent here. In contrast to numerous descriptions of analogous species and varieties from China and India, I found in my Asian material only L. acanthocercoides in the northern part of the continent (some Chinese populations are specific, see above), and L. ciliata in the southern part, and no other species. Some published illustrations seem to be dealing with other, unknown species, but may be extreme cases of variability, or incorrect representation of animals in illustrations due to the author's style of drawing.

Leydigia hardingi Nayar, 1971 is very similar to ciliata , and no taxonomically significant trait was reported by the author. I did not see any reason for its independent status, but this opinion must be checked by consideration of Indian samples.

The South American records of L. ciliata ( Harding 1955, Infante 1980) dealt with L. striata . Some Chinese animals (i.e. in Chiang Sieh-chin and Du Nan-shan 1979; Shen Chia-jui ae al. 1964; Chen Shouzhong 1993) are more similar to L. acanthocercoides .

See further discussion in Kotov et al. (2003b)

Distribution. Widely distributed in tropical and subtropical Africa, Asia, also present (although not common) in Australia; penetrating southernmost portions of Africa and Australia with relatively moderate climate; the northern border of its area is not yet determined.

Junior synonym of L. ciliata : Leydigia ankammaraoi Prasad, Santa Kumari et Bose, 1986

Type locality. "Rice fields of Mutluru and Uppalapadu, Guntur District, and a fish farm located near Vuyyuru, Krishna District" ( Prasad et al. 1986), lower delta of the River Krishna, Andhra Pradesh, India.

Holotype. Adult parth. ♀, slide NHM 1984.214 .

Paratype. Parth. ♀, tube NHM 1984.215 .

Taxonomical comments on junior synonym. According to the description of Prasad et al. (1986), their species has a well-developed basal spine and five setae on the exopodite of limb III, thus belongs to the Leydigia (Leydigia) subgenus. But both the holotype and paratype have no basal spine and have only 3 setae on exopodite III, so it belongs to the Leydigia (Neoleydigia) acanthocercoides group; no differences from the aforementioned ciliata were found. Most probably, the authors used a mixed sample with two species for their 'description of new species'. I think that if the first description contradicts the holotype, the holotype has priority, although this situation is not described in the ICZN (2000). Therefore, L. ankammaraoi is a junior synonym of L. ciliata .