Corresponding author: Jans Morffe Rodríguez (
Academic editor: H.-P. Fagerholm
The new genus
The family
The
Australia shows a characteristic fauna of hystrignathids, with the endemic and monotypic genera
In Cuba, the study of this group is recent (
Five specimens of
Beetles from La Jaula were kept alive in plastic jars with moistened wood chips as food and a humidity source. They were killed as soon as possible with ethyl ether vapours and dissected as described above. The intestines were dissected in normal saline instead of water. Nematodes removed from guts were killed with hot water (60–70°C) and fixed in 70% ethanol.
In this study the type material of
Nematodes were clear-mounted on slides in glycerine and coverslips were sealed around the edges with nail polish. Measurements were made after
Micrographs were taken with an AxioCam digital camera attached to a Carl Zeiss AxiosKop 2 Plus compound microscope. Line drawings were made with the softwares CorelDRAW X3 and Adobe Photoshop CS2 using micrographs as templates. Scales of all the plates are given in millimetres.
The materials examined are deposited in the CZACC and the Coleçao Helmintologica do Instituto Oswaldo Cruz (CHIOC), Rio de Janeiro, Brazil.
Family
Female. Body robust, markedly fusiform. Cervical cuticle unarmed. Lateral alae present, from the esophageal region to a distance before the level of the vulva. Head bearing eight small, paired papillae. First cephalic annule slightly expanded, set-off from head by a deep single groove, its fore half with concave margins when totally relaxed. Esophagus consisting of a muscular sub-cylindrical procorpus, its base abruptly expanded in its joint with the short isthmus. Intestine simple, its fore region very expanded, forming a sac-like structure. The end of this region of the intestine is abruptly set-off and next to it the gut continues as a simple, rectilinear tube. Nerve ring encircling procorpus at its posterior half. Excretory pore post-bulbar. Reproductive system didelphic-amphidelphic. Eggs large, ovoid, smooth-shelled. Tail long, subulate and filiform.
Male. Body shorter and more slender than female. Cervical cuticle without spines. Head similar to female. First cephalic annule inconspicuous. Digestive system similar to female. Nerve ring encircling procorpus at its posterior half. Excretory pore post-bulbar. One testis present. Spicules absent. Tail conical, very short, sharply pointed, ventrally curved, its dorsal cuticle thickened forming a
Cuba.
The generic name is a combination of Coy, after Alberto Coy Otero, eminent Cuban parasitologist and the suffix –nema. The name is in neuter gender.
♂ holotype of
5 ♀♀, Cuba, Pinar del Río Province, Sierra del Rosario, El Mulo; in
Gut caeca.
El Salón, Sierra del Rosario, Pinar del Río Province, Cuba.
El Mulo, Sierra del Rosario, Pinar del Río Province, Cuba; La Jaula, San José de las Lajas, La Habana Province, Cuba; La Melba, Nipe-Sagua-Baracoa, Holguín Province, Cuba.
Holotype (male) a = 14.40, b = 5.74, c = 83.08, total length = 1.080, maximum body width = 0.075, stoma length = 0.018, procorpus length = 0.130, isthmus length = 0.023, diameter of basal bulb = 0.038, total length of esophagus = 0.188, nerve ring to anterior end = 0.098, excretory pore to anterior end = 0.260, cloaca to posterior end = 0.013.
Allotype (female) a = 16.69, b = 9.15, c = 4.41, V% = 52.63, total length = 2.470, maximum body width = 0.148, first cephalic annule (length×width) = 0.013×0.035, stoma length = 0.025, procorpus length = 0.200, isthmus length = 0.025, diameter of basal bulb = 0.065, total length of esophagus = 0.270, nerve ring to anterior end = 0.130, excretory pore to anterior end = 0.370, vulva to posterior end = 1.170, anus to posterior end = 0.560, eggs = 0.113–0.118×0.048–0.050 (0.116 ± 0.004×0.049 ± 0.001 n = 2).
Females (n = 5) a = 17.00–19.72 (18.25 ± 1.32 n = 4), b = 7.73–8.65 (8.18 ± 0.38 n = 4), c = 3.65–3.99 (3.82 ± 0.17 n = 4), V% = 46.99–52.94 (49.50 ± 2.84 n = 4), total length = 1.700–2.075 (1.863 ± 0.164 n = 4), maximum body width = 0.090–0.120 (0.102 ± 0.011 n = 5), first cephalic annule (length×width) = 0.008–0.013×0.023–0.030 (0.010 ± 0.002×0.026 ± 0.004), stoma length = 0.018–0.020 (0.019 ± 0.001 n = 5), procorpus length = 0.160–0.175 (0.166 ± 0.006 n = 5), isthmus length = 0.023–0.025 (0.023 ± 0.001 n = 5), diameter of basal bulb = 0.040–0.045 (0.043 ± 0.002 n = 5), total length of esophagus = 0.220–0.240 (0.226 ± 0.009 n = 5), nerve ring to anterior end = 0.108–0.128 (0.119 ± 0.009 n = 5), excretory pore to anterior end = 0.340 (0.340 n = 1), vulva to posterior end = 0.800–1.100 (0.944 ± 0.133 n = 4), anus to posterior end = 0.430–0.520 (0.484 ± 0.038 n = 5), eggs = 0.105–0.113×0.035–0.048 (0.110 ± 0.003×0.040 ± 0.003 n = 11).
Females (n = 11) a = 13.13–20.00 (16.26 ± 1.95 n = 11), b = 7.65–9.33 (8.35 ± 0.53 n = 11), c = 3.93–4.49 (4.22 ± 0.19 n = 10), V% = 47.72–51.92 (50.44 ± 1.07 n = 11), total length = 1.740–2.425 (2.010 ± 0.211 n = 11), maximum body width = 0.108–0.150 (0.125 ± 0.014 n = 11), first cephalic annule (length×width) = 0.005–0.008×0.028–0.033 (0.007 ± 0.001×0.029 ± 0.002 n = 7), stoma length = 0.020 (0.020 n = 11), procorpus length = 0.163–0.185 (0.174 ± 0.008 n = 11), isthmus length = 0.020–0.028 (0.023 ± 0.003 n = 11), diameter of basal bulb = 0.043–0.058 (0.049 ± 0.005 n = 11), total length of esophagus = 0.228–0.260 (0.240 ± 0.010 n = 11), nerve ring to anterior end = 0.120–0.140 (0.130 ± 0.006 n = 11), excretory pore to anterior end = 0.280–0.360 (0.320 ± 0.029 n = 11), vulva to posterior end = 0.860–1.200 (0.996 ± 0.107 n = 11), anus to posterior end = 0.400–0.560 (0.478 ± 0.061 n = 10), eggs = 0.108–0.125×0.035–0.048 (0.116 ± 0.004×0.042 ± 0.004 n = 20).
Females (n = 6) a = 13.27–16.00 (14.80 ± 0.95 n = 6), b = 6.77–8.38 (7.53 ± 0.57 n = 6), c = 3.35–3.84 (3.60 ± 0.20 n = 6), V% = 43.18–48.24 (44.92 ± 2.27 n = 4), total length = 1.460–1.800 (1.653 ± 0.126 n = 6), maximum body width = 0.110–0.120 (0.112 ± 0.004 n = 6), first cephalic annule (length×width) = 0.010×0.025–0.028 (0.010×0.027 ± 0.001 n = 5), stoma length = 0.018–0.020 (0.018 ± 0.001 n = 6), procorpus length = 0.153–0.173 (0.160 ± 0.008 n = 6), isthmus length = 0.018–0.200 (0.019 ± 0.001 n = 6), diameter of basal bulb = 0.043–0.065 (0.048 ± 0.009 n = 6), total length of esophagus = 0.200–0.240 (0.220 ± 0.014 n = 6), nerve ring to anterior end = 0.113–0.125 (0.119 ± 0.006 n = 6), excretory pore to anterior end = 0.270–0.360 (0.307 ± 0.047 n = 3), vulva to posterior end = 0.820–1.000 (0.894 ± 0.076 n = 4), anus to posterior end = 0.380–0.530 (0.462 ± 0.052 n = 6), eggs = 0.105–0.125×0.035–0.048 (0.113 ± 0.006×0.043 ± 0.004 n = 11).
Males (n = 4) a = 10.84–13.18 (11.87 ± 1.05 n = 4), b = 5.62–6.03 (5.88 ± 0.18 n = 4), c = 55.00–74.67 (66.92 ± 8.39 n = 4), total length = 1.030–1.120 (1.073 ± 0.044 n = 4), maximum body width = 0.085–0.095 (0.091 ± 0.004 n = 4), stoma length = 0.015–0.020 (0.017 ± 0.002 n = 4), procorpus length = 0.125–0.300 (0.128 ± 0.002 n = 4), isthmus length = 0.015–0.023 (0.018 ± 0.004 n = 4), diameter of basal bulb = 0.040–0.048 (0.044 ± 0.003 n = 4), total length of esophagus = 0.175–0.188 (0.183 ± 0.005 n = 4), nerve ring to anterior end = 0.093–0.100 (0.096 ± 0.003 n = 4), excretory pore to anterior end = 0.240–0.250 (0.248 ± 0.005 n = 4), cloaca to posterior end = 0.015–0.020 (0.016 ± 0.003 n = 4).
Female. Body comparatively robust, markedly fusiform, maximum width at level of the anterior part of intestine. Cervical cuticle unarmed, finely annulated (annule more conspicuous toward post-esophageal region). Sub-cuticular longitudinal striae present. Lateral alae from the end of procorpus or the beginning of its basal dilation to about half of a body width before the level of vulva. Head well developed, set-off from body by a single, deep groove and bearing eight small paired papillae. First cephalic annule slightly expanded, when totally stretched (in dead nematodes inside the hosts) consisting of an anterior half with concave margins (its diameter initially inferior to that of head and increasing gradually in the posterior direction) and a posterior half wider and with convex margins. In heat-relaxed specimens the cephalic annule appears to be less stretched and only the posterior part is visible. Stoma short, about two first cephalic annule lengths long, surrounded by an esophageal collar. Esophagus consists of a muscular, sub-cylindrical procorpus, base abruptly dilated in its joint with the short isthmus. Basal bulb pyriform, valve plate well developed. Intestine simple, sub-rectilinear, anterior portion notably dilated, forming a sac-like structure slightly longer than esophagus. In this part the external surface of intestine almost touching the body wall. The continuation of intestine is about one third of the diameter of the sac-like structure. Rectum short, anus not prominent. Nerve ring encircling procorpus at about 60% of its length. Excretory pore situated at about half of a body width posterior to basal bulb. Genital tract didelphic-amphidelphic, both ovaries thin, reflexed. Anterior ovary commencing just behind the saccular structure and posterior ovary arising slightly more than a body width anterior to the level of anus. Vulva a median transverse slit near midbody or slightly displaced forward, lips more or less prominent. Vagina muscular, thin-walled, forwardly directed. Conduct next to the vagina forming a loop. Eggs comparatively large, markedly ovoid in shape, smooth-shelled. Tail comparatively long, filiform and subulate.
Male. Body shorter and slender than female. Cervical cuticle unarmed. Sub-cuticular longitudinal striae present. Cephalic end similar to female, except by the cephalic annule inconspicuous. Digestive system similar to female. Sac-like region of the intestine slightly larger than the esophagus. Rectum short and cloaca inconspicuous, not prominent. Nerve ring encircling procorpus in posterior half, at about 60% of its length. Excretory pore situated at about less than a body-width posterior to the basal bulb. Testis single, commencing just posterior to the sac-like structure of intestine. Tail conical, sharply pointed, very short and ventrally curved. Dorsal cuticle near the tail tip bearing a Y-like thickening, its inferior part posteriorly directed. A single, median, large, mammiform pre-cloacal papilla present. A pair of small, sub-dorsal, pre-cloacal papillae situated before the dorsal cuticular thickening. Spicules absent.
There are eight hystrignathid genera that are digonant and lack spines in the cervical cuticle:
The male of
There are small metric differences in the average values among females from some of the populations studied. In spite of this measurements tend to overlap, and there were no evident morphological differences observed. Males from El Salón and La Melba did not show marked morphometric variation. In addition, no male specimens were found in the populations from El Mulo and La Jaula, when looking for more features that would support the existence of other species of
We are indebted to our colleagues Elier Fonseca, Gunnary León (Universidad de La Habana), Ormaily Madruga (Museo Nacional de Historia Natural), Rayner Núñez, René Barba (Instituto de Ecología y Sistemática), the undergraduate student Facundo Alvarez and David Ortiz for their help during the field work. To the inhabitants of La Jaula community (La Habana Province) for their hospitality and support. To MSc. Yamir Torres (Instituto de Ecología y Sistemática) and Dr. Alejandro Barro (Universidad de La Habana) for their help with the micrographs. We also thank Dr. Luis F. de Armas from the Instituto de Ecología y Sistemática for his critical review of the manuscript and Dr. Pedro Herrera for the revision of the English manuscript. This work was financed by IDEAWILD and the project “Colecciones Zoológicas, su Conservación y Manejo” (DB-06) of the Ministerio de Ciencia, Tecnología y Medio Ambiente, Cuba.