Neochordodes occidentalis ( Montgomery, 1898 )

Schmidt-Rhaesa, Andreas & Menzel, Lena, 2005, Central American and Caribbean species of horsehair worms (Nematomorpha), with the description of three new species, Journal of Natural History 39 (7), pp. 515-529 : 525

Neochordodes occidentalis ( Montgomery, 1898)

( Figure 2D, E )

Chordodes occidentalis Montgomery 1898: 50–52 .

Neochordodes occidentalis: Poinar and Doelman 1974: 328–330 .

Pseudochordodes occidentalis: de Miralles and de Villalobos 1993: 108 .

Material studied

Two newly reported males from Mammoth Tusk Cave and Veracruz, Mexico; LM and SEM .

Description

The two male specimens from Mexico measure 16 and 18 cm in length, and 0.9 and 1.1 mm in diameter, respectively. The body colour is a medium brown, the anterior tip is white, a dark collar is not present. The posterior end of the males is round, without tail lobes. The cloacal opening is surrounded by short spines, further, very short spines are distributed in the ventral region around the cloacal opening.

The cuticle contains one type of areole, that varies in shape from rounded to polygonal ( Figure 2D, E ). The interareolar grooves are very narrow and contain only few bristles ( Figure 2E ). A megareolar pattern (see P. bulbareolatus ) is not clearly visible. In some instances, areoles approach very close, but tubercles could not be observed.

Comments

Previous descriptions of N. occidentalis are heterogeneous (see Schmidt-Rhaesa et al. 2003). It is not quite clear, whether this indicates that N. occidentalis is a polymorphic species or whether more than one species are summarized under this name. However, the newly reported specimens from Mexico correspond in the cuticular ultrastructure to the holotype from California, USA ( Montgomery 1898; see also reinvestigation by Schmidt-Rhaesa et al. 2003). Due to the presence of a single type of areole (which is very variable), we follow here the assignment to the genus Neochordodes .

Distribution

New records. Mexico: Mammoth Tusk Cave, San Francisco, one male, coll. 5 January 1976 by D. Lowery and P. Strickland; Veracruz, Sumidero de Tlaltenango (1.4 km N Tlaquilpa), 2330 m, one male, coll. 23 March 1995 by C. Savas (both Texas Memorial Museum, Austin, USA, no accession number) .

Further distribution. USA (California, Montana, Nebraska, Nevada, Texas, Utah, Washington, Wyoming; see Schmidt-Rhaesa et al. 2003) .

Figures

Figure 2. (A–C) Pseudochordodes manteri. (A) Light microscopical image showing two types of areole, single dark, elevated areoles (white arrows) and flat areoles in the megareolar pattern (black arrows); (B, C) SEM image of larger areoles. (D, E) Neochordodes occidentalis, SEM images of cuticle.