Pseudochordodes bulbareolatus, Schmidt-Rhaesa & Menzel, 2005

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 : 517-519

Pseudochordodes bulbareolatus nov. sp.

( Figure 1 )

Holotype: Mexico, Veracruz, Sumidero de Tlaltenango (1.4 km N Tlaquilpa), 2330 m, one male, coll. 23 March 1995 by C. Savas (Museum für Naturkunde , Berlin, Germany, accession number ZMB Entozoa 7377) . Paratype: one male, collection data as holotype (Texas Memorial Museum , Austin, USA, no accession number). Further record: Guatemala (not further specified) , one female ( Natural History Museum , London, accession number 83.5.24) .

Description

The two males measure 16 (holotype) and 19.5 (paratype) cm in length and 0.8 and 1.5 mm in diameter, respectively. Their anterior end is white and blends into the medium brown colour of the body. A dark collar, which is present in many other nematomorph species, is not present. There are dark brown patches distributed over the whole cuticle which contrast with the medium brown colour of the cuticle (‘‘leopard pattern’’; Schmidt- Rhaesa et al. 2003).

The posterior end of the two males is round, without tail lobes. The cloacal opening is oval and surrounded by short, unbranched spines. There are some short bristles on the ventral side of the posterior end around the cloacal opening.

The cuticle is structured by rounded to polygonal areoles which are separated by narrow interareolar grooves with short bristles ( Figure 1A–D ). The surface of these areoles is rough. Among these areoles, few form the megareolar pattern (see Schmidt-Rhaesa 2001), in which two areoles adjoin each other along one side and enclose a short tubercle between them ( Figure 1A–D ). Rarely, isolated tubercles can also be found in the interareolar grooves. Over the whole cuticle, some regions containing 7–12 areoles, are elevated ( Figure 1A–D ). In the centre of these elevations are large areoles forming a megareolar pattern. They are surrounded by a varying number of ‘‘simple’’ areoles.

Comments

The presence of elevated regions composed of several areoles is unique and justifies the description of a new species. The characterization of the genus Pseudochordodes is as nematomorphs with an undivided male posterior end, in which the cuticle contains two types of areoles ( Carvalho 1942). In some species, this is clearly evident (e.g. P. gordioides , see Schmidt-Rhaesa et al. 2003), but in others, the recognition of two types of areole is more difficult and species are sometimes assigned to Neochordodes , in which only one type of areole is present ( Carvalho 1942). In Pseudochordodes bulbareolatus , areoles in the bulging clusters are slightly larger than the surrounding ones and occur in a different pattern, which justifies the placement within the genus Pseudochordodes .

Figures

Figure 1. Pseudochordodes bulbareolatus n. sp. (A) Light microscopical preparation of body cuticle showing bulging clusters of areoles; (B–D) SEM overview (B, C) and detail (D) of bulging areolar clusters with areoles in a megareolar pattern in the centre.