Huntia morffei, Zhang & Yin & Carreno & Zhang, 2021

Zhang, Ningning, Yin, Shi, Carreno, Ramon A. & Zhang, Luping, 2021, Three new genera and new species of hystrignathid nematodes (Nematoda: Thelastomatoidea) from passalid beetles (Insecta: Passalidae) from Yunnan Province, China with phylogenetic analysis of Hystrignathidae, Zootaxa 5071 (2), pp. 206-222 : 209-210

Huntia morffei gen. n. et sp. n.

( Figs. 1-2 )

Type-host: Ceracupes fronticornis ( Westwood)

Type-locality: Bubang Village , Sipsongpanna, Yunnan Province, China (21°35’53”N, 101°34’54”E).

Type-material: Holotype female (HBNU-I-2021013); paratypes: 9 females (HBNU-I-2021014–2021022).

Prevalence: 8.7 % (10 infected out of 115 examined)

Intensity: 2–11 (mean 7) specimens.

Site in host: Hindgut.

Representative DNA sequences: One partial 28S and one partial 18S rDNA sequence of the new species are deposited in the GenBank database under the accession numbers MZ330362 and MZ330364 , respectively.

Etymology: The specific epithet is named after Jans Morffe, Curator of the Helminthological Collection, Instituto de Ecología y Sistemática, Cuba for his contributions to the thelastomatoid nematodes.

Description. Female body comparatively large and robust, widening from base of head. Maximum body diameter near mid-body, gradually tapering towards anus. Cervical cuticle unarmed, without annulation. Body cuticle with distinct transverse striations and longitudinal striations ( Fig. 2A ). Lateral alae narrow, originating from middle of oesophageal procorpus and extending to level of anus. Head cone-like, truncate, continuous with body but without transverse and longitudinal striations, bearing 8 rounded papillae arranged in 4 pairs. Amphids pore-like, laterally situated. Oral opening oval, surrounded by a cuticular ring ( Fig. 2A, B ). First cephalic annule absent. Stoma very short ( Fig. 1D ), as long as head length, surrounded by an oesophageal collar. Oesophagus consisting of a muscular, subcylindrical procorpus, short isthmus, and spherical basal bulb with valve plate well developed. Intestine simple, sub-rectilinear, anterior portion slightly dilated ( Fig. 1A, B ). Nerve ring encircling procorpus at its posterior third. Excretory pore situated posterior to basal bulb. Vulva located near mid-body, with lips slightly salient ( Fig. 2C ). Vagina muscular, anteriorly directed. Didelphic-amphidelphic. Anterior ovary reflexed at about one half body width behind excretory pore, posterior ovary reflexed at about one body width before the anus. Eggs ovoid, ornamented with rough longitudinal ridges on shell ( Figs. 1E , 2D ). Eggs arranged transversely in a single row in uteri ( Fig. 1A ). Conical tail, subulate, ending in a sharp tip ( Fig. 1C ). Male not observed. Measurements in Table II.

Remarks. In the Hystrignathidae there are three genera in which the females present the unarmed cervical cuticle, sub-cylindrical procorpus and didelphic reproductive system: Anomalostoma Cordeiro, 1981 ; Coynema Morffe & García, 2011 , and Kongonema Morffe & García, 2013 .

Anomalostoma can be easily distinguished from the new genus by having the anterior part of the stoma strongly swollen. Huntia gen. n. differs from Coynema by having the sub-cylindrical procorpus and the anterior region of the intestine slightly inflated instead of the base dilation of procorpus and the anterior region of the intestine notably inflated. The new genus is different from Kongonema in having the head continuous with the body vs. the head separating from the body by a deep groove, and in having the cervical region without annulation vs. the strongly annulated cervical region.

Figures

FIGURE 1. Huntia morffei gen. n. et sp. n. Female. A: Whole body, lateral view; B: Anterior part of body, lateral view; C: Posterior end of body, lateral view; D: cephalic end of body, lateral view; E: egg. scale bars: A, B, C, D, E = 100 μm.

FIGURE 2. Huntia morffei gen. n. et sp. n. female. SEM images. A: Cephalic end, en face view, showing cephalic papillae (cp) and amphids (am); B: Cephalic end, lateral view; C: vulva; D: egg.