Tardigrades of North Carolina

Scientific Name:		Family:	Order:	Class:

View PDF	Echiniscidae Members:	1 NC Records
Hypechiniscus gladiator group - No Common Name

Dorsolateral, PC Scottish population Gasiorek et al 2021

Taxonomy

Class: Heterotardigrada	Order: Echiniscoidea	Family: Echiniscidae	Checklist Number: 2060.0
Taxonomic Comments: This record is probably Hypechiniscus daedalus. At the time of this study H. gladiator was considered to be cosmopolitan. Gasiorek et al (2021) used integrative taxonomy to untangle a pseudocryptic cluster of species and described the new species H. daedalus and concluded that it is likely endemic to N. America. Hypechiniscus gladiator is verified only in Scotland and Iceland, thus we have changed this record to H. gladiator group.
Species Notes: Terrestrial.

Identification

Online resources:

Online Photographs: Google, GBIF

Species Description: For H. gladiator proper:
Females (i.e. from the third instar onwards; measurements and statistics in Table 4): Body whitish and stout (Figs 3A, C, 4), with spheroid or ovoid black eyes, persisting also after mounting. Elongated, dactyloid cephalic papillae (secondary clavae) and (primary) clavae (Figs 3A, C, 5A, B); peribuccal cirri without cirrophores (Fig. 5B). Cirrus A short, with cirrophore (Figs 3A, 5A). Long cirrus dorsalis with a triangular base inserted posterior to median plate 2 (Figs 3A, C, 4), the flagellum occasionally subdivided into two cirri. Dorsal plates poorly sclerotized, with the Pseudechiniscus-type sculpturing, that is endocuticular pillars protruding through the epicuticle and visible as densely packed dark dots in PCM (Fig. 3A), bumps in NCM (Fig. 3C) or weakly elevated protrusions (granules) in SEM (Fig. 26C). Epicuticular ornamentation in the form of ridges visible in LCM and SEM (Figs 3A, C, 4, 26C). Generally, the sculpture is well-developed and evident in LCM. The cephalic plate is large and pentapartite, with two small anterior portions, a central keel-like portion and two larger trapezoid portions (Figs 3A, 4A, 5A). The cervical (neck) plate is not visible in LCM, indistinctly merged with the anterior margin of the scapular plate in SEM (Fig. 5A). The scapular plate falsely divided in two parts by a central longitudinal suture and by numerous epicuticular ridges (Figs 3A, 4A, 5A, 6A). Three median plates, all pseudobipartite, falsely subdivided by transverse sutures (Fig. 6A) and with six pairs of lateral intersegmental platelets flanking their borders (Figs 3A, 4A, 6A). Two pairs of large segmental plates without marginal incisions, but with a complicated system of epicuticular ornamentation giving an impression of false subdivisions (Figs 3A, 6A). Caudal (terminal) plate large, with long incisions (Figs 3A, 4A, 6A). Ventral cuticle with a clear species-specific pattern of ornamentation reaching the lateroventral sides of the body (Figs 3A, 4B). Ornamentation composed of epicuticular thickenings and endocuticular pillars of variable sizes, which are tightly arranged and closely adjacent to each other (Figs 4B, 6B). The largest and most evident pillars occur between legs II and legs III, and in the gonoporal zone, where pillars are densely aggregated and form pseudoplates. Subcephalic zone with a pair of large pseudoplates, and the subcervical area with a slender columnar or pedestal shaped aggregation or plate (Fig. 6B). Sexpartite gonopore placed between legs III and legs IV and a trilobed anus between legs IV. Pedal plates and dentate collar IV absent, instead large belts of pillars are present on the outer central part of each leg (Fig. 5D). Weak pulvini present on all legs. Markedly sclerotized areas present at the inner side of each leg below the claws (Fig. 3C). A small papilla on leg I present and visible in SEM (Fig. 5A); a papilla on leg IV present (Fig. 4A). Claws I–IV of equal heights. External claws on all legs smooth (Fig. 5C–D). Internal claws with massive spurs positioned at c. one-quarter of the claw height and strongly bent downwards. Fragments of upwardly bent epicuticle formed as pseudoaccessory points on all claws (visible only in SEM; Fig. 5C, arrowheads).
-Gasiorek et al. 2021

Body Length: 166-300 microns

Key Characters: Conspicuous dorsal cirrus, external claws lacking spurs, papillae absent on legs II–III present on legs IV, Only dorsal endocuticular pillars visible in DIC or PC.

Key Character Images

ID Requirements: Identifiable only by close inspection of key characters or by DNA analysis.

Distribution in North Carolina


Distribution:
County Map: Clicking on a county returns the records for the species in that county.


Dates: High Mountains (HM) ≥ 4,000 ft. Low Mountains (LM) < 4,000 ft. Piedmont (Pd) Coastal Plain (CP) Click on graph to enlarge

Habitats and Life History

Habitats: Moss and lichen and other terrestrial habitats.

Abundance: Unknown.

Diet: Herbivorous.

Reproduction: Smooth eggs laid in shed exuvium.

Observation Methods: PC/DIC/SEM

Wikipedia

Photo Gallery for Hypechiniscus gladiator group - No common name		Photos: 8
	Recorded by: Higgins on 1959-04-15 Durham Co. Comment: Dorsolateral, PC Scottish population Gasiorek et al 2021	Recorded by: Higgins on 1959-04-15 Durham Co. Comment: Ventrolateral, PC Scottish population Gasiorek et al 2021
	Recorded by: Higgins on 1959-04-15 Durham Co. Comment: Lateral, PC Scottish population Gasiorek et al 2021	Recorded by: Higgins on 1959-04-15 Durham Co. Comment:
	Recorded by: Higgins on 1959-04-15 Durham Co. Comment: Lateral SEM Scottish population Gasiorek et al 2021	Recorded by: Higgins on 1959-04-15 Durham Co. Comment: Head SEM Scottish population Gasiorek et al 2021
	Recorded by: Higgins on 1959-04-15 Durham Co. Comment: Claws, PC and SEM Scottish population Gasiorek et al 2021	Recorded by: Higgins on 1959-04-15 Durham Co. Comment:

Hypechiniscus gladiator group - No Common Name

Photo Gallery for Hypechiniscus gladiator group - No common name

Photos: 8