Ceratophysella jondavi ( Wray, 1946 )

Bernard, Ernest C., 2015, Redescriptions of Hypogastruridae and Onychiuridae (Collembola) described by David L. Wray, Zootaxa 3918 (3), pp. 301-338 : 307-309

Ceratophysella jondavi ( Wray, 1946)

Fig. 4

Achorutes jondavi Wray 1946: 79 .

Ceratophysella jondavi Salmon 1964: 216 (as jondaui); Christiansen & Bellinger 1980: 148, 1998: 155.

Specimens examined. Lectotype female and 21 paralectotypes on slides (by present designation), numerous paralectotypes in ethanol, USA, North Carolina, Raleigh, Bloomsbury Park, 9 December 1943, mushrooms on rotted log, G. F. Knowlton, coll.

Redescription. Body length up to 0.95 mm [up to 1.6 mm]. [Body with yellow background sprinkled with reddish-rust-colored specks heavier on head and antennae]. Granulation fine to moderate, granule width 2.3–2.8 Μm; Yosii’s ‘a’ number 11–12. Body setae consisting of smooth, setiform macrosetae and mesosetae, longest subcoxal setae serrated ( Fig. 4 A). Head with all dorsal setae; setae c4, d2, d4, d5, p1, p2, p4 and v2 macrosetae. Lateral seta of pronotum slightly longer than more medial setae. Thoracic and abdominal sensilliform setal lengths equal to or longer than neighboring p-setae. On mesonotum, m-row lacking seta m2 but with extra seta m3’; setae p2, p5 and p6 macrosetae, seta p2 forward of p1 and p3. Metanotum lacking seta m2 and extra seta m3’, p2 and p5 macrosetae, p2 slightly forward of p3; microsensillum not observed. Tergites I–III with setae p2, p6 and occasionally p4 as macrosetae. On Abd. IV p2 as a macroseta, m1 slightly thickened; on Abd. V p1 a macroseta. Seta a3 missing on abdominal tergites I–III, present on tergites IV and V. M-row setae m2, m3 and m4 usually present on Abd. I–IV, m2 and m3 occasionally missing. Seta p1 much longer than p2 on tergite V ( Figs. 4 A, B); 3+3 anterior setae inside the p5 setae. Subcoxae I–III with 1, 2, 2 setae, respectively, the longer setae serrate. Plurichaetosis absent.

Antennal segment IV with weakly bilobed or entire apical vesicle, without prominent, granulated apical protrusions ( Figs. 4 D, E). Subapical organite of Ant. IV very small, peg-like, microsensillum minute, rod-like in pit; two lateral and five dorsal sensilla, the lateral sensilla plumper than the dorsal sensilla; nearly all dorsal setae sensilliform, most ventral setae setiform. Ventral sensory field with 25–30 slender, capitate or brush-tipped sensilla, one sensilliform seta near center of sensory field, three longer, rounded subapical sensilla and straight apical sensilliform seta ( Fig. 4 E). Sense organ of Ant. III ( Fig. 4 D) with two oval sensilla in shallow groove flanked by longer tapering sensilla; slender peg-like microsensillum present on Ant. III ( Fig. 4 E). Eversible sac between Ant. III and IV present. Antennal segment I with 7 setae, Ant. II with 12 setae.

Postantennal organ width up to twice the diameter of nearest ocelli, anterior lobes longer and broader than posterior lobes, accessory tubercle present ( Fig. 4 F). Labrum roughly trapezoidal, anterior edge straight medially; basal two-thirds granulate, with four linear tubercles; setal formula 5, 5, 4. Maxilla with lamella 1 finely serrated and ciliated, extending past capitulum head; lamella 4 longer than lamella 2; bifurcated “toothbrush” present ( Fig. 4 G). Sublobal hairs of outer maxillary lobe not seen clearly. On labial palpus ( Fig. 4 H) lengths of sensilla A–E equal to or shorter than most guard setae; a1 and b1 ovate, b2, d2 and e2 spine-like, lateral papilla lp conical; guard setae b3, b4, d3 and, d4 spatulate, all e guard setae linear; guard setae d1 and e7 absent. Labial palpus with six proximal setae.

Tibiotarsi I, II, and III with 19, 19, 18 setae, respectively. Clavate tenent hairs absent. Unguis ( Fig. 4 I) slender with one basal pair of small lateral teeth and ventral tooth. Unguiculus with basal lamella and terminal spine not reaching ventral tooth.

Ventral tube with 4+4 setae. Tenaculum with 4+4 teeth, without setae. Dens less than twice length of mucro, strongly tuberculate dorsally, with seven setae; inner three setae slightly to greatly swollen, usually strongly serrated in basal half; outer setae slender and smooth ( Figs. 4 J‒L). Mucro spoon-shaped, tuberculate basally, apex rounded, with strong outer lamella ( Figs. 4 J‒L). Anal spines on short basal papillae, upright, short, about half the length of inner edge of hind unguis.

Remarks. Ceratophysella jondavi is a member of the C. denticulata -group. Christiansen & Bellinger (1980, 1998) examined a single type specimen and another specimen attributable to C. jondavi , and counted 16 granules in Yosii’s “a” measure, but noted in their Ceratophysella character chart (Table VII, p. 138) that the number was “16±”. To reach C. jondavi in their key, seta p1 on Abd. IV would need to be longer than seta p2. However, their chart of Ceratophysella characteristics indicates that p1 is shorter than p2. Assuming the chart is correct, C. jondavi will trace to a couplet that separates the maheuxi and denticulata groups by Yosii’s “a” measure (maheuxi 16 or more, denticulata 14 or less). If the higher number is used C. jondavi traces to H. (C.) krafti ( Fjellberg 1985) , which is a Mitchellania -group species. The lower number places C. jondavi in the denticulata -group, where it is very similar to the “ exilis ” form ( C. exilis ( Yosii 1956) also see Yosii (1962)) and C. palustris ( Martynova, 1978) (also see Fjellberg 1985).

The validity of C. jondavi can be questioned and it could be considered a variant of C. denticulata (Bagnall, 1941) , but until better resolution can be attained for this species complex it is better to keep well-described taxa separated.

Figures

FIGURE 4. Ceratophysella jondavi. A) Dorsal chaetotaxy, lectotype. B) Dorsal chaetotaxy of fourth and fifth abdominal segments, paralectotype. C) Anal spines. D) Third and fourth antennal segments, dorsal view. E) Fourth antennal segment, ventral view. F) Postantennal organs and anterior eyes, lectotype (above), paralectotype (below). G) Head of maxilla, lectotype. H) Labial palpus, lectotype; t = bilobed “ toothbrush. ” I) Hind foot complex. J ‒ L) Dentes and mucrones from adult, adult, and late juvenile paralectotypes, respectively.