Chordodes gestri Camerano, 1904

Villalobos, C. De & Zanca, F., 2005, Ultrastructural redescription of Chordodes moraisi (Carvalho, 1942) and Chordodes straviarskii Carvalho and Feio, 1950, and re-interpretation of Chordodes gestri Camerano, 1904 and Pseudochordodes griffinii (Camerano, 1898) (Gordiida, Nematomorpha), Journal of Natural History 39 (8), pp. 597-606 : 602

[ Chordodes gestri Camerano, 1904 ]

( Figure 3 )

Chordodes gestri Camerano 1904, p 93 .

Holotype: one male, Quezaltenango Guatemala Museo Regionale di Science Naturali, Torino, Italy ( MZUT G34 ) . Paratype: one female, Museo Regionale di Science Naturali , Torino, Italy ( MZUT G34 ) .

Material examined. Holotype: SEM anterior end, posterior end and midbody. Paratype: SEM anterior end and midbody.

Host. Unknown.

Camerano (1904) described a male and a female from Guatemala with three types of areole. One type of short areole of variable dimensions; a second type of large areole arranged in groups of 7–10 between which a tubercle emerges, and a third type of areole distributed among type 1 areoles and with a small tubercle (see also Camerano 1915). These characters are not sufficient for the description of a new species belonging to the genus Chordodes , because the diagnostic feature of Chordodes is the existence of a specialized type of areole, called crowned areoles, which were not described for this species ( De Villalobos and Zanca 2001; Schmidt-Rhaesa 2002a; De Villalobos et al. 2004). The reason why Camerano (1904) included this species in the genus Chordodes is seen to be unknown. In a SEM investigation the posterior end of the holotype is undivided, and a ventral groove is present. The cloacal opening is slit-like and surrounded by unbranched or apically branched circumcloacal spines ( Figure 3A, B ). The cuticle of the holotype and the paratype contains areoles of one type, which vary in size ( Figure 3C ). A megareolar pattern is present mainly in the midbody region. Among some of these large areoles a rounded apex tubercle emerges ( Figure 3C ). All the areoles are very close together. In the mid-anterior body region this areolar pattern changes and the areoles are of similar sizes, some with superficial furrows. The interareolar furrow is large with scattered small tubercles ( Figure 3D ).

The features observed in the cuticle along the body allow us to relate these two specimens of Chordodes gestri with the holotype and with the specimen from Nebraska of Neochordodes occidentalis (Montgomery, 1898) which were studied by Schmidt-Rhaesa et al. (2003, Figure 13A, F). Therefore, we regard Chordodes gestri as a synonym of Neochordodes occidentalis .

Figures

Figure 3. SEM of male of ‘‘Chordodes gestri’’ holotype. (A, B) Ventral view of posterior end: (A) whole posterior end with cloacal opening (arrow); (B) cloacal opening with circumcloacal bristles. (C) Cuticle at the midbody with megareolar pattern. (D) Areolar pattern in the anterior region of the body. Scale bars: 100 mm (A); 50 mm (B); 10 mm (C, D).