Cathetocephalus badilloi, Río & Iv & Hern & andez-Mena & Vidal-Martínez, 2023

Río, Itzel Nayely Badillo-Del, Iv, David, Hern, an G., andez-Mena & Vidal-Martínez, Víctor M., 2023, Cathetocephalus badilloi n. sp. (Cestoda: Cathetocephalidea) from the spinner shark Carcharhinus brevipinna off the coast of Yucatan, Mexico, International Journal for Parasitology: Parasites and Wildlife 21, pp. 168-173 : 171

publication ID	https://doi.org/ 10.1016/j.ijppaw.2023.05.003
DOI	https://doi.org/10.5281/zenodo.10933417
persistent identifier	https://treatment.plazi.org/id/038787F2-6C27-5560-3A48-078FFC0AA39C
treatment provided by	Felipe
scientific name	Cathetocephalus badilloi
status	sp. nov.

Treatment

3.1. Cathetocephalus badilloi View in CoL n sp.

3.1.1. Description (based on four organisms)

Total length from anterior end of scolex to posterior end of strobila (2424.72 ± 98.91) ( Fig. 2A View Fig ). Scolex, a fleshy organ positioned perpendicular to the strobila, length: 215.10 ± 11.99; width: 929.35 ± 14.07 ( Fig. 2B View Fig ), lacking suckers or acetabula, hooks, bothridia and/or tentacles. Scolex composed of three bands: an apical pad, a band of papillae, and a rough base ( Fig. 2C View Fig ). Apical pad; width: 45.46–49.34 μm ( Fig. 2D View Fig ), with minute ridges positioned in parallel, spaced from one another along the base ( Fig. 2E View Fig ). Band of papillae, width: 100.27–105.99 μm, composed of two papillary sections ( Fig. 2F View Fig ). Upper section, width: 50.66–52.99 ( Fig. 2G View Fig ) has numerous lumpy papillae with a heterogeneous surface, positioned irregularly with each other, which maintains a spongy texture along the band. Lower section, width: 51.54–53.00 composed of numerous papillae positioned one next to the other, with no space between them, giving the appearance of a compact fence. This section presents flattened rectangular papillae with molar tooth shape, and with a finger-shaped division in the apical area of each papilla, width: 30.24 (±3.89) ( Fig. 2H View Fig ). Rough base width of 40.83–41.79, with homogeneous flat surface without ridges or rough features ( Fig. 2I and J View Fig ). Microtriches not observed on rough base surface or strobila ( Fig. 2K and L View Fig ). Strobila length: 2157.45 ± 76.38; width: 56.98 ± 10.64), without developed proglottids.

3.1.2. Taxonomic summary

Type host: Carcharhinus brevipinna , ( Carcharhiniformes : Carcharhinidae ) Spinner shark.

Host length: 79.55 cm (±6.96) (n =9).

Type locality: Progreso , Yucatan, Mexico latitude 22 ◦ N longitude 90 ◦ E, zone 10; region northeast-west ( Fig. 1 View Fig ) GoogleMaps .

Site of infection: spiral valve.

Individuals infected = 2/9, prevalence: = 22%, mean abundance: 3 (±1.4).

Specimens deposited: holotype (No. 11784) and paratypes (No. 11785) in the helmintological collection of the Instituto de Biología , UNAM .

Etymology: named Cathetocephalus badilloi n. sp. in honor of the first author’ s father, Gonzalo Badillo, for his unconditional support, life advice, and love.

3.2. Remarks

Cathetocephalus badilloi n. sp. is easily distinguishable among the recorded species of the genus, because it has a papillary band composed of two sections. The lower section, constituted of numerous papillae stacked one next to the other with no space between them, gives the appearance of a compact fence. This band was considered as one of the diagnostic characters for its identification, since it has the characteristic of presenting molar-shaped papillae which is thick, rectangular, and flattened with a finger-like division located in the upper part of each one ( Fig. 2F View Fig ). These papillary structures belonging to C. badilloi n. sp. are also shorter (30.24 ± 3.89 width) than those of C. thatcheri papillae, which are long and thinner (3–5 width) ( Caira et al., 2005). The scolex of C. badilloi n. sp. is smaller in length: 215.10 ±11.99 and width: 929.35 ± 14.07 than that of C. thatcheri ; [width; 6100 (4000–10,000) ( Dailey and Overstreet, 1973; Caira et al., 2005)]. C. australis also has a wider scolex than C. badilloi n. sp. (1120–2900 vs 910–942.58) ( Schmidt and Beveridge, 1990). In addition, C. australis possesses a narrower band of papillae than the apical pad of C. badilloi n. sp. ( Fig. 2C View Fig ). Also, the lower segment papillae of C. badilloi n. sp. present rectangular shape. In fact, these rectangular papillae in C. badilloi n. sp. are different from those of C. resendezi which has bottle-shaped lower papillae and cluster-shaped upper papillae (Fig. 20 in Caira et al., 2005). Similarly, the microtriches that appear on the rough base and the strobila in C. resendezi do not appear in C. badilloi n. sp. In the case of Cathetocephalus sp. described by Caira et al. (2005), microtriches were present on the surface of the strobila and the rough base. C. badilloi n. sp. differs from Cathetocephalus sp. in the lack of microtriche structures on the rough base and on the surface of the strobila. However, C. badilloi n. sp. shares with Cathetocephalus sp. the presence of small sinuous ridges and slightly perpendicular spaces on the surface of the apical pad. Both have a similar pad:papillate band:rugose radius ratio: Cathetocephalus sp. 1 :1.5:0.5 vs. C. badilloi n. sp. 1:1.5:0.6. In contrast, the values for these characteristics for other species in the genus are: C. thatcheri 1:2.3:2.8; C. australis 1:1.3.3 ( Caira et al., 2005). The specimens of Cathetocephalus badilloi n. sp. had no mature or gravid proglottids. However, as Caira et al. (2005) stated, in several Cathetocephalus species, the structures of the proglottids are highly variable, and thus, problematic for identification at the species level ( Caira et al., 2005). By this reason, even when we did not have access to the proglottids, for this genus we felt they were not essential since the most useful characters were in the scolex.