Coronatella monacantha ( Sars, 1901 )

Sousa, Francisco Diogo Rocha, Elmoor-Loureiro, Lourdes Maria Abdu & Santos, Sandro, 2015, Redescription of Coronatella poppei (Richard, 1897) (Crustacea, Branchiopoda, Chydoridae) and a revision of the genus in Brazil, with descriptions of new taxa, Zootaxa 3955 (2), pp. 211-244 : 233-238

Coronatella monacantha ( Sars, 1901)

( Fig. 11)

= Alona monacantha in Sinev (2004), pg. 9–10, figs. 1–22.

Type locality. Ipiringa, São Paulo state, Brazil. No further comments were made by Sars (1901).

Lectotype. Females, Zoological Museum of Oslo University, sample F 12332 a.

Other material examined. Six adult parthenogenetic females from the Jurumirim Reservoir, São Paulo, Brazil (23 º 16 ' 35.67 "S, 49 º 5 ' 10.94 "W), material collected by José Roberto Debastiani-Júnior. Five adult parthenogenetic females from Nhumirim Embrapa Farm, Baía- 49, Mato Grosso do Sul, Brazil (19 º 00' 14.9 "S, 56 º 38 ' 06.9"W), material collected by Valéria Barros on 07.ix. 2000 (EL02243). Two adult parthenogenetic females from pond located in Paranã River floodplain, Goiás, Brazil (15 º 09’ 15.8 "S, 47 º 28 ’ 04.7"W), material collected by Ciro Joko on 20.viii. 2003 (EL00717). Seven adult parthenogenetic females from a pond in vicinity of São José do Mipibú, Rio Grande do Norte, Brazil (06º 04' 45 "S, 35 º 14 ' 17 "W), material collected by Lourdes M. A. Elmoor- Loureiro on 20.vii. 1985 (EL02122). Eight adult parthenogenetic females from the Swamp at the Ypioca Farm, São Gonçalo do Amarante, Ceará, Brazil (3 º 34 ’ 39 "S, 8 º 52 ’ 31 ”W), material collected by Maria Beatriz Gomes e Souza on 19.xii. 2007.

Comments. The morphology of the studied populations almost completely agrees with the recent redescription of this species (Sinev 2004), with only one exception observed in the inner portion of Limb V. In this appendage, we can observe an inflated element, variable in size, inserted behind the inner setae ( Fig. 11 B–C). In the postabdomen, we can observe spinules along the whole dorsal margin of the basal spine ( Fig. 11 D). Agreeing with Sinev (2004), we found intrapopulational and interpopulational variations in the denticle on the posteroventral corner of carapace and labral keel ( Fig. 11 E–G). The position of the lateral head pores exhibited variation in comparison to data from Sinev (2004) ( Fig. 11 K).

C. rectangula C. poppei C. paulinae C. serratalhadensis C. undata sp.nov. C. monacantha

sp.nov. sp.nov.

0.25-0.40 0.30-0.44 0.29-0.33 0.27-0.36 0.24-0.36 0.19-0.30> PP * 1.4 times 2.2 times 1.6 times 1.4 times 2.0 times Labral keel, denticles - - - - - + Ventral setae, groups + + + + - + of ventral setae 30-40 34-40 28-33 28-38 34-38 35 - denticles - - - - two one – groups of spinules - - - three groups - - 1 antennular body/ antennular seta 2.3 2 1.8 1.7 2.8 2.9 length

Nº marginal denticles 6-7 8-9 5-6 5-6 5-6 5-6 Nº lateral fascicles 5 7 5-6 5-6 4-5 6-7 length of basal spine/base of the 2 1.2 1.2 2.6 2.5 2.5 terminal claw

Nº of rows of setules on the limb 7 7 7 6 6 5 ODL seta vs. longest seta of the ODL ≅ IDL ODL ≅ IDL ODL ≅ IDL ODL ≅ IDL ODL <IDL ODL ≅ IDL IDL reduced seta + - - + - - exopodite seta long long absent long rudimentary reduced Nº of setae on the fc 7 7 6 7 6 7 fourth setae of the ex short short long short long long length of seta 3 /length of seta 5 2.3 3.2 2.9 2.6 4.2 2.4 length of seta 4 /length of seta 5 2.0 3.3 1.9 2.3 1.8 2.3 ex depression between setae 3-4 - - + - + - fc - - + - - -

Distribution and biology. Coronatella monacantha is the most well-known Neotropical species of the genus and occurs in many types of aquatic environments, including artificial ones ( Fig. 13). Regarding natural water bodies, this species may be found in permanent and temporary ponds, swamps, lakes, rivers, streams and floodplains (Howelldel et al. 2003; Sousa et al. 2009; Van Damme & Dumont 2010). Populations of C. monacantha in Brazil have been associated with large macrophyte beds, especially Eichornia azurea (Serafim- Junior et al. 2003), and also with slightly acid waters ( pH between 4–6). According to Sousa et al. (2011), C. monacantha is very sensitive to environmental conditions, and reductions in water quality can result in morphological abnormalities.