Cateria gerlachi Higgins, 1968

Neuhaus, Birger & Kegel, Antje, 2015, Redescription of Cateria gerlachi (Kinorhyncha, Cyclorhagida) from Sri Lanka and of C. styx from Brazil, with notes on C. gerlachi from India and C. styx from Chile, and the ground pattern of the genus, Zootaxa 3965 (1), pp. 1-77 : 42-44

Cateria gerlachi Higgins, 1968 from India

( Fig 19 , Tables 2, 4, 11)

Description. The three females with eggs ( Fig. 19B ) and the single adult specimen agree in their habitus, spine formula, and measurements (Table 2) with the original description by Higgins (1968). Characters like the long spines anterior of the primary spinoscalids, individual placids (with type-5 sensory spot with a curled tube below the cuticle subdorsally, midlaterally, and lateroventrally), outer oral styles alternating in length and consisting of three elements ( Fig. 19C ), the thin and transparent trunk cuticle, the cuticular surface composed of scales ( Fig. 19E, F ), the primary fringe consisting of thin spinose hairs, appearance and arrangement of leaf-like cuticular hairs ( Fig. 19 E, F ), composition and arrangement of the secondary fringe (4–6 lines of leaf-like hairs and posterior line of spinose hairs on segments 3–6), and morphology of sensory spots, gland cell outlets and papillae ( Table 4; Fig. 19E, F ) harmonize with those of C. gerlachi from Sri Lanka. They are, therefore, not repeated here. In the following, only those characters are mentioned that differ either from the original description or from that of the specimens from Sri Lanka.

In the only available specimen in dorsoventral mount and in a second specimen in oblique mount, the midventral sternal plate of segment 6 does not seem to possess at its posterior margin a midventral posterior notch but an undivided margin ( Fig. 19D ). It remains unclear whether or not a midventral sternal plate exists on segment 7, but probably not. The tergal plate of segment 11 does not seem to meet midventrally in a partial or full junction.

On segment 5, all specimens reveal in the lateral accessory position a tube with a broader base and an internal tubular substructure ( Fig. 19F ).

The general arrangement of sensory spots, gland cell outlets, and papilla agrees with the situation described for this species from Sri Lanka, but some positions disagree. Whereas in the Indian material a type-5 sensory spot occurs sublaterally on segments 3 and 4 (posterior part of segment) and on segment 10 (central part) as well as ventrolaterally on segment 1 (posterior part) and segment 11 (anterior part), these spots are usually missing in the specimens from Sri Lanka ( Tables 4, 5). The animals from India possess two gland cell outlets midlaterally on segment 2 and one lateroventrally on segment 2, but specimens from Sri Lanka usually lack one of the midlateral outlets and the lateroventral gland cell outlet ( Tables 4, 5). Vice versa, a lateroventral gland cell outlet on segment 4 appears in the material from Sri Lanka, but is missing in the specimens from India.

Sexual dimorphism. One specimen ( USNM 1226519 ) differs in two characters from females with obvious eggs in their gonads. This potential male agrees in all cuticular characters with the female but can be distinguished from the female (1) by a modified acicular spine lateroventrally and middorsally on segment 10 and (2) by the existence of an almost rectangular cuticular flap about midlaterally and anteriorly on segment 11 vs the lack of this structure in the female. The lateroventral and middorsal acicular spine on segment 10 of the male is not straight as in females but modified revealing a broader base and tapering towards its tip. Also, the tip of these spines is bent upwards terminally and possesses an indentation in this part. The lateroventral spine reveals a broader base. Unfortunately, almost all spines got lost in the process of restoration .

The head is partly protruded, so some trichoscalids become visible on one side, namely a long paradorsal, a short subdorsal, and a long midlateral trichoscalid.

The single male is in the process of moulting. The new cuticle becomes visible mainly at the posterior end of the specimen and in the spines ( Fig. 19A ). Elongate sperm cells cannot be traced.

Figures

FIGURE 19. Male (A), female (B–D) and adult with female characters (E, F) of Cateria gerlachi from India, LM. A, segments 8–11 of moulting specimen, left side; notice new cuticle in the lateral terminal and lateral terminal accessory spine, other spines lost during restoration; B, segments 6–11 with eggs (arrows) in gonads, optical section; C, segments 1–6 with outer oral styles, optical section; note different length of basal element of neighbouring styles (arrows); D, segments 1–6, ventral view; notice rounded midsternal plate on segment 6 (arrowheads); E, segments 1–4, right side; F, segments 4–7, left side; spines on segments 6 and 7 lost. Arrows mark type-1sensory spots, and arrowheads point to type-5 spots in E and F. Extended focus image of 7 (E) and 6 (F) images. Scalebar: A (valid for B–F), 50 µm.