Cryptopygus coenobitus Palacios-Vargas 2024, sp. nov.
Creators: name: Palacios-Vargas, José G.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Collembola
Entomobryomorpha
Isotomidae
Cryptopygus
Cryptopygus coenobitus

description: Cryptopygus coenobitus sp. nov.
Figs 1–4, 5–8, 9–12, 13–16
Type material.
Holotype. Female on slide. Paratype: male on slide. Type material kept at Facultad de Ciencias, UNAM. Slides numbered: FC-UNAM: LESM-AC: 22863 and FC-UNAM: LESM-AC: 22864.
Type locality.
Mexico – Quintana Roo • Municipality of Solidaridad; Xcacel; ex. Coenobita clypeatus; 20 ° 20 ' 13 " N, 87 ° 20 ' 45 " W; 6 June 2022; J. G. Palacios-Vargas, M. Ojeda & A. Arango leg.
Diagnosis.
White and eyeless Cryptopygus, with 9 + 9 to 11 + 11 postlabial setae, 1 pair of lateral teeth on unguis; retinaculum with 4 + 4 teeth and 3–4 setae on corpus, 11–14 pairs of manubrial setae on anterior surface, and 17–18 pairs on posterior surface, dens smooth, 4 setae on posterior basal part and 11–13 on anterior side, mucro bidentate.
Description.
Setae smooth, acuminate, mostly short, some micro- and few slightly barbulated macrosetae (40–50 µm). Sensilla on terga in posterior row of setae, only slightly differentiated from ordinary setae, thinner and hyaline (Figs 1, 2). Microsensillum on Th. II normal. Abd. V and VI completely fused. Dorsal setation from Th I to Abd IV, 15, 8 / 4, 4, 5, 8 irregular lines (Fig. 1). Thorax without ventral setae. Abd VI without foil setae. Sensillar formula from Th II to Abd V: 3, 3 / 2, 2, 2, 3, 2.
Length of head 140–150 µm, length of body 750–1000 µm. Antennae 250 µm, longer than head (ratio = 1: 1.75). Ratio Ant. I – IV as 1: 1.5; 1.5; 2.5. Ant. I with 33–36 setae, 9 thin and short ventral sensilla; Ant. II with 54 setae with few microsensilla and one thick, long sensillum on ventral – distal position (Fig. 3). Ant. III with 44 setae, antennal organ III with 2 microsensilla, 2 fine guard sensilla and 1 ventro-external microsensillum. Ant IV with about 70 setae, and 8 long and fine sensilla. Apex of the segment with a microsensillum and a small organite, apical bulb absent. Eyes absent, postantennal organ oval (25 × 12 µm), surrounded by 5 setae (Fig. 4). Labrum with 4 short, thin prelabral setae; 4 long setae in anterior row, 5 spiniform setae in median row, and 4 spiniform setae in posterior row, formula 4 / 4, 5, 4. With 4 sublobal hairs on outer maxillary lobe; labium with full set of guards on papillae A – E, and 3 proximal and 4 baso-median setae. Postlabial setae 9 + 9-11 + 11 (Fig. 5). Mandibles with 3–4 apical teeth and molar surface well developed (Fig. 6). Maxilla with 6 lamellae, with some plumose (Fig. 7).
Thorax without ventral setae. All femora with 1 ventral acuminate tenent hair. Tita with 2, 3, 3 acuminate tenent hairs and without a distal subsegment (Fig. 8). Tita I = 60 µm, Tita = 80 µm. Unguis I = 13 µm, unguiculus I = 11 µm. Unguis with 1 pair of lateral teeth in the median part. Unguiculus lanceolate, acuminate, not lamellate, almost as long as unguis. Ventral tube with 4 + 4 basal setae and 5 + 5 latero-distal setae (Fig. 9). Abd. IV on ventral surface with 4 + 5 setae by side; anterior subcoxa furcalis with 19–20 setae; posterior subcoxa furcalis with 10 setae, 4 of them longer than others (Fig. 10).
Tenaculum with 4 + 4 teeth, corpus with 3–4 setae (Fig. 11). Furcula well developed, manubrium with 11–14 pairs of anterior setae (Fig. 12), 3 small lateral setae and 18 pairs of setae on posterior side. (Fig. 13). Dens smooth, only 4 setae of different size on posterior basal part and 10–14 subequal setae on anterior surface (Fig. 14). Manubrium 80 µm, dens 100 µm, mucro 25 µm. Ratio 1: 1.25; 0.3. Mucro bidentate. Genital plate of female with 2 eugenital setae and 5 pairs of pregenital setae (Fig. 15). Male with 4 pairs of eugenital setae and a few circumgenital setae (Fig. 16).
Etymology.
This species is a noun in apposition after the genus of the hermit crab in which it was found.
Distribution.
Cryptopygus coenobitus sp. nov. is only known from Xcacel, Quintana Roo State, Mexico.
description: Published as part of Palacios-Vargas, José G., 2024, A new Mexican species of the Cryptopygus complex (Collembola, Isotomidae) associated with the hermit crab Coenobita clypeatus (Crustacea, Coenobitidae), pp. 89-99 in ZooKeys 1205 on pages 89-99, DOI: 10.3897/zookeys.1205.114394