Laophontella Thompson & Scott, 1903

Björnberg, Tagea & Kihara, Terue C., 2013, On Tetragonicipitidae (Crustacea, Copepoda) from the Channel of São Sebastião, Brazil, with description of their nauplii and two new species of Phyllopodopsyllus, Zootaxa 3718 (6), pp. 501-529 : 527

Genus Laophontella Thompson & Scott, 1903

Laophontella horrida (Por 1964) ( Fig. 20 )

Material examined. São Sebastião Is., Parcel da Praia Grande (23º51’30’’S 45º25’00”W): One female, 2 males, 2 copepodites. 14 Feb. 2007. Oliveira J. M. coll. São Sebastião, Guaecá Beach, Itaçucê (23º50’00”S 45º26’62”W): One nauplius. 0 8 Feb. 2006. Pepato, A. coll.

Decription of nauplius. The dorsal shield of the nauplius ( Fig. 20 A) 470 µm long, covered with furrows and striations. Two medial lateral processes are followed by two more bifid lateral processes and one posterior small pointed process and these complete the ornamentation of the dorsal shield. The furcal region of the body is prolonged into two bifid projections onto which the posterior setae are inserted. The dorsal shield is strongly furrowed and rugose externally.

Labrum: wide and finelly setullous distally.

Labium (part of the ventral wall, just below the labrum) bears 2 patches of setules posteriorlly.

Antennule ( Figs 20 A–B) long and thin, but also rugose proximally, and distinctly divided into 3 segments of which the last bears 10 setae.

Antenna. Exopod with 4 setae, and segmented. Endopod with 2 lateral setae and distal claw. Coxa with a masticatory process bearing 3 thick setae: inner seta distally divided into a 3-pointed fork with a minute inner seta, a middle seta distally denticulated, and an outer glabrous seta. Basis: a process with 3 setae.

Mandible: Coxabasis externally spinulous, innerly confluent with endopod. This bears a bifid seta, 3 pointed setae, and 2 foliaceous setae. Exopod 2-segmented with a pinnate seta on first segment and 2 long setae on second segment (one longer seta, twice the length of the other).

Maxillule: maxilla and maxilliped are represented by pointed lateral body projections as in Fig. 20 B.

Remarks. Laophontella horrida (Por, 1964) has a subspecies L. h. dentata Mielke, 1992 which occurs in Costa Rica. Males and female found agree in their general aspect but not in details with Mielke’s specimens. The furca and the antennules are like Por’s (1964) illustrations of the species

Por (1964) figured a nauplius together with L. horrida . It agrees in general aspect with the nauplius which we found in samples collected in São Sebastião Channel waters where the adults occurred. It has the characteristic long, thin antennules of the other Tetragonicipitidae nauplii.

Figures

FIGURE 20. Laophontella horrida (Por, 1964) (nauplii). (A) NIV, dorsal; (B) NIV, ventral. Scale bars: 25 µm.