A REVIEW OF THE GORDIACEA (NEMATOMORPHA) IN THE COLLECTION OF THE CALIFORNIA ACADEMY OF SCIENCES WITH THE DESCRIPTION OF A NEW SPECIES

The Gordiacea of the California Academy of Sciences collection are studied. The specimens are included in the known species Gordius robustus Leidy, Pseudochordodes bedriagae (Camerano) and a new species, Neochordodes californensis n. sp. is proposed. Morphological, morphometric and geographical data are provided for these species.

The material studied in this paper belongs to the collection of the California Academy of Science assembled after the 1906 earthquake.It includes new material from different localities in California, Mexico and Canada.The specimens (so far unidentified) examined for this study belong in the following species: Gordius robustus Leidy, Pseudochordodes bedriagae (Camerano) and Neochordodes californensis n. sp.Data on morphological and meristic features are provided as well as data on the geographical range of the species.
The material was examined through a Leitz Wetzlar binocular and the drawings were made using a camera lucida.To analyze the cuticle, the central zone of the body was thin sectioned and the muscles and internal organs were separated by means of dissection needles.The cuticle was mounted on Chloralactophenol.All measurements are in millimeters.

Gordius robustus
Males: A specimen measuring 337 mm long and 2.196 mm wide.Twenty three specimens, with a length between a maximun of 330 mm and a mini-mum of 160 mm, and an average of .535mm wide.Anterior end attenuated (fig.1), distal edge semicircular.Mouth terminal and central (fig.2); in one of the specimens the head was retracted within the body.In other specimens the head is not colored and is separated from the rest of the body by a dark neck ring.Body color yellow brownish; shape cylindrical, with dorsal and ventral very shallow and narrow longitudinal furrows poorly developed.Posterior end slightly thinner than central region and developed into two inwardly curved lobes (figs.3 and 4).Lobular sizes ranging from .406 to .648mm long and .192 to .321mm wide.Postcloacal ridge conspicuous and semicircular.Cloacal aperture rounded and placed in front of the ridge, with a diameter ranging between .032 and .094mm.Cuticle smooth devoid of areolae with underlying net-like muscular lines that can be seen by transparency.
Females: Twenty five specimens with a length between a maximum of 371 mm and a minimum of 156 mm, and an average width of .625 mm.
Anterior end semicircular (fig.5).Head poorly colored and, as in males, separated from the rest of body by a dark ring.Diameter of anterior region, measured at the ring, ranging from .288 to .695mm.Mouth terminal and central, placed at the very tip of the anterior end.General color is light brown.Dorsal and ventral longitudinal furrows poorly developed.Posterior end claviform, wider than the average width, which ranges between .481 and .845mm.Most females observed show a flaccid body, possibly due to having been captured immediately after oviposition.Many of them still show eggs clustered to the posterior end (fig.6).The cuticle is smooth, devoid of any kind of ornamentation.
( Males: Nine specimens with a length between a maximum of 396 mm and a minimum of 133 mm, and an average width of .820mm. Anterior end of examined males pointed with an average diameter of .332mm.(fig.7).Body brown, head light yellowish.Dark neck ring absent.Body body cylindrical with depressions on different areas.Ventral longitudinal groove conspicuously developed.Posterior end rounded (fig.8), spiral shaped in an apically tapering spoon-like prolongation, average diameter of .450mm.Cloacal aperture ovate, subterminal, placed within a slight ventral depression.Largest diameter of .09mm.Younger specimens colored light brown, like females.Cuticle (fig.9) with two types of areolae: a) high and dark, generally polygonal, paired or in groups of three, sometimes isolated; these are usually separated by a porous canal with sessile bristles and b) low variable in shape and color and ranging over most of the cuticle; interareolar furrows free of tubercles, bristles or other formations.
Females: Tree specimens with a length between a maximum of 296 mm and a minimum of 281 mm, and an average width of 1.350 mm.
The sharply tapering anterior tip ends in a cream-colored hemisphere surrounded posteriorly by a dark zone; average diameter of anterior end about .532.The rest of the body is light brown, flattened and with numerous longitudinal folds due to recent oviposition.Dorsal and ventral longitudinal lines poorly defined.In some specimens the posterior end is retracted, in others is appears turgid, claviform and wider than the rest of the body; average diameter is .641mm.Several females show eggs adhered to the distal edge.The cuticle is as in the males.
Large tropical gordiaceans; thin anterior end; body cylindrical; posterior end attenuated; slightly flattened dorsally in males; males with a shallow mid-ventral cloacal groove; cuticle with only one kind of areolae, generally ovoid and low compared to the ones in Chordodes; interareolar furrows with or without hyaline processes, bristles or other structures.Female: Holotype, a specimen 89 mm long and .568mm wide (diameter?).Cylindrical.Anterior end pointed (fig.10).Head retracted within body; diameter of .366mm behind retraction.Cloaca terminal and central (fig.11).Color light brown, except for head, which is not pigmented.Mid-ventral groove well developed.The cuticle shows only one kind of areolae, which are irregularly quadrangular or polygonal, with rounded corners.On most areolae there is a circle of small protuberances placed near the areolar edge.The interareolar spaces are very narrow and devoid of hyaline processes, bristles or other structures (figs.12 and 13).

Neochordodes californensis
Remarks: After a comparative analysis of the cuticler features of N. californensis with other species of the genus, we can cconclude that it differs from N. colombianus Faust and Ramos in that the areoles are quadrangular or poligonal and that the suprareolar structures are excentric.From N. talen- sis (Camerano) it differs by the low areoles, lacking granulations and by the narrow interareolar furrow and the lack of hialine processes.From N. nietoi it can be distinguished because of the uniform areole distribution.The areoles have a rounded surface with irregular contours.It can be separated from N. senearolatus Carvalho by the narrower interareolar spaces and the semicircular areolar contours, the absence of tubercles, bristles or other cuticler structures.All this suggests that the specimen studied shows distinctive features that warrant its inclusion in a new species.