Longior longior Morffe & García, 2011

Morffe, Jans, García, Nayla, Breugelmans, Karin & Adams, Byron J., 2018, Morphological examination and phylogenetic analysis clarify the taxonomic status of Cuban Longior Travassos & Kloss, 1958 (Nematoda: Thelastomatoidea: Hystrignathidae), Zootaxa 4399 (4), pp. 521-542 : 524-533

Longior longior Morffe & García, 2011

Fig. 1 A–H , Fig. 2 A–G , Fig. 3 A–F , Fig. 4 A–I

Longior longicollis Travassos & Kloss, 1958 ; Coy, 1990: 5 –6, fig. 3 A–C, misidentification Longior alius García & Coy, 1994: 13 –15, fig. 1 A–C

Material examined. Vouchers: 3♀♀, Cuba, Pinar del Río province, San Diego de los Baños, Las Yeguas; in Antillanax pertyi ; 31/V/2014; S. Yong coll.; CZACC 11.4974–11.4976 . 12♂♂, same data as the latter; CZACC 11.4977–11.4988 . 2♀♀, same data as the latter; MNHNSD 05.007–05.008 . 3♂♂, same data as the latter; MNHNSD 05.009–05.011 .

Vouchers: 2♀♀, Cuba, La Habana province, Arroyo Naranjo, El Volcán ; in Antillanax pertyi ; IX/2013; E: Pardo coll.; CZACC 11.5019–11.5020 . 19♂♂, same data as the latter; CZACC 11.5021–11.5040 .

Vouchers: 5♀♀, Cuba, Sancti Spíritus province , Trinidad, Topes de Collantes, Codina ; in Antillanax pertyi ; X/ 2014; J. Morffe, N. García coll.; CZACC 11.4899–11.4903 . 4♂♂, same data as the latter; CZACC 11.4904– 11.4907 .

Vouchers: 10♀♀, Cuba, Sancti Spíritus province , Trinidad, Topes de Collantes, path to the River Caburní ; in Antillanax pertyi ; 12/X/2014; J. Morffe, N. García coll.; CZACC 11.4908–11.4917 . 7♂♂, same data as the latter; CZACC 11.4918–11.4924 .

Vouchers: 15♀♀, Cuba, Sancti Spíritus province , Trinidad, Topes de Collantes , path “Jardín de los Gigantes”; in Antillanax pertyi ; 14/X/2014; J. Morffe, N. García coll.; CZACC 11.4935–11.4949 . 6♂♂, same data as the latter; CZACC 11.4950–11.4955 .

7♀♀, Cuba, Guantánamo province , El Salvador, Limonar ; in Antillanax pertyi ; VI/2013; J. Morffe, N. García, M. Olcha coll.; CZACC 11.4761–11.4767 . 17♂♂, same data as the latter; CZACC 11.4768–11.4784 . 2♀♀, same data as the latter; CHIOC 38415 a–b . 2♂♂, same data as the latter; CHIOC 38415 c–d . 2♀♀, same data as the latter; RIT . 1♂♂, same data as the latter; RIT.

Redescription. Female. Body long and comparatively slender, widening gradually posterior to head, reaching its maximum width at level of the vulva, then narrowing gradually towards tail. Cuticle thin. Sub-cuticular striae present. Cervical cuticle unarmed, with wide annuli (ca. 5 µm) from the base of the first cephalic annule to ca. the level of the first third of procorpus. Lateral alae well developed, extend from ca. three body-widths posterior to the basal bulb to the level of the anus. Head bearing eight paired, digitiform cephalic papillae arising from the external edge of head, at ca. half of its height. A cuticular, veliform annular lip surrounding the triradiate oral opening.

Amphids lateral, at level of the base of the cephalic papillae. First cephalic annule comparatively long, truncate, slightly dilated, ca. 1.5–2 head-lengths long. Stoma long and slender, surrounded by an oesophageal collar. Oesophagus consists of a muscular, sub-cylindrical procorpus, its base similar in diameter to the isthmus. Basal bulb pyriform, valve-plate well-developed. Intestine simple, sub-rectilinear, its fore region slightly dilated. Rectum comparatively long. Anus a crescent-like ventromedian slit, anteriorly directed, not prominent. Nerve ring encircling procorpus at ca. 20% of its length. Excretory pore located at ca. one body-width posterior to the basal bulb. Vulva a median transverse slit ca. 40 µm in length, its lips not prominent, located at level of midbody. Vagina muscular, forwardly directed. Genital tract monodelphic-prodelphic, comparatively short, occupying only ca. 20% of the body length. Distal end of the ovary reflexed at ca. two body-widths posterior to the excretory pore, distal flexure ca. two body-widths long. Oocytes in a single row. Eggs ellipsoidal, bearing eight rough, prominent longitudinal ridges in the shell that do not reach the poles. Gravid females with 1– 7 eggs at a time in the uterus. Phasmids barely evident, pore-like, lateral, located at a short distance (ca. 5 µm) posterior to the end of lateral alae. Tail conical, subulate, ending in a fine tip.

Male. Body comparatively shorter and more slender than females. Posterior region ventrally curved in heatfixed specimens. Cervical cuticle unarmed, markedly annulated up to a little distance before the nerve ring, annuli ca. 2 µm. Rest of body with less conspicuous annuli (ca. 1 µm), up to level of the dorsolateral pair of papillae. Lateral alae narrow, extend from the oesophageal region at level of the last third of procorpus to a short distance (ca. half of the body width) before the level of the median pair of copulatory papillae. Head set-off from body by a deep groove, bearing eight ellipsoidal, slightly flattened cephalic papillae; arranged as two sub-dorsal and two subventral pairs. Six digitiform lips arise from the internal edge of the cephalic papillae and project to the center of the oral aperture. Lips are arranged as one dorsal lip, one ventral, two sub-dorsal and two sub-ventral. The sub-dorsal and sub-ventral lips flank the dorsal and ventral lips, respectively. Amphids lateral, crescent-like. Oesophagus consists of a muscular, sub-cylindrical procorpus, its diameter diminishing towards its posterior half, almost equaling the diameter of the cylindrical isthmus at the level of their junction. Basal bulb spherical, valve plate well evident. Intestine simple. Nerve ring encircling procorpus at ca. 35% of its length. Excretory pore located at ca. 0.7 of a body-width posterior to the basal bulb. Monorchic. Testis outstretched. Vas deferens with three distinguishable regions: an anterior region with granular content; a median, slightly swollen region, also granular (granuli slightly shorter in diameter) and a posterior region that diminishes its diameter through the cloaca. Spicule absent. A bursalike structure present. Dorsal cuticle of the posterior end thickened and smooth from the tail tip to ca. the midpoint between the ventromedian pair of papillae and tail tip. Such thickening forms a cuticular crest at the tail tip that extends terminally and laterally until the level of the distal end of the bursa. Phasmids pore-like, lateral, located at level of the first third of the bursa. Four pairs of copulatory papillae, two pre-cloacal and two post-cloacal. A ventromedian pre-cloacal large pair, consisting of duplex papillae very close to each other on an ellipsoidal protuberance (appear to be a single papilla in lateral view) at ca. 120 µm from the tail tip. One sub-lateral precloacal pair of papillae at ca. 50 µm from the tail tip. The first post-cloacal pair consists of small papillae, ventral, located at the tip of a papilliform protuberance just posterior to the bursa. Such protuberance is posteriorly oriented, almost reaching the level of the tail tip. Last pair of post-cloacal papillae small, ventral, sub-terminal, close to the tail tip, located below the terminal cuticular crest.

Remarks. The presence of marked annuli in the cervical cuticle of Longior species has been used as a feature of taxonomic importance ( Morffe & García 2011; 2012; Morffe et al. 2009). The females of L. longior are distinguished by a lack of marked annuli, as opposed to L. elieri , L. similis and L. panamensis where the cervical cuticle is notably annulated. Also, males of L. similis have been differentiated from those of L. longior , the former having the cervical cuticle smooth vs. annulated ( Morffe & García 2011). However, in the current study, we identified some female specimens of L. longior as well as male L. similis exhibiting annulations on the cervical cuticle, contradicting the previous statements.

The presence of such annuli could arise because of contraction of the cuticle of the specimens after heat-killing rather than an inherent characteristic of the species. Therefore, other features should be considered for differential diagnosis, i.e. those related to morphometrics, morphology of the first cephalic annule, female genital tract, position of the nerve ring and excretory pore, tail shape, and arrangement of male copulatory papillae.

In addition to the monodelphic-prodelphic female genital tract characteristic of the genus, the length of the distal flexure of the ovary was used by Morffe & García (2011; 2012) for the diagnosis of species. In the present analysis we noticed that the length of the genital tract occupies a proportion of the body that remains more or less constant. The genital tract of L. longior is very short, occupying ca. 20% of the total length of body. That differs from L. similis females, whose genital tract represents ca. 40% of their body length. L. elieri and L. panamensis are similar by having reproductive systems occupying ca. 30% of the body length. Based on line drawings ( Hunt 1981), L. semialata also resembles both latter species, with ca. 30%.

……continued on the next page Measurements not included in the original description.

In Western Cuba, L. longior was previously recorded from El Salón and El Mulo, Sierra del Rosario, Artemisa province and La Jaula, San José de Las Lajas, Mayabeque province (formerly La Habana province) ( Coy 1990; Coy et al. 1993; Morffe & García 2011; Morffe et al. 2009). Las Yeguas, San Diego de los Baños, Pinar del Río province and El Volcán, La Habana province constitute new records from Western Cuba, the former locality being the westernmost distribution of the species in the Cuban archipelago.

The records from Codina, river Caburní and the path “Jardín de los Gigantes” in the Gran Parque Natural Topes de Collantes extends the distribution of the species to Sancti Spíritus province, as well as Central Cuba. Moreover, the localities of La Matazón (for L. alius ) and Limonar are the first records from Guantánamo province in Eastern Cuba, where L. longior was previously recorded from La Platica, Granma province and La Melba, Holguín province ( García et al. 2009b; Morffe et al. 2009). The specimens from these new localities coincide morphologically and morphometrically ( Tables 1 and 2) with previously recorded populations.

Although most of the records of L. longior are from A. pertyi , some authors ( Coy 1990; Coy et al. 1993) also recorded it from the host P. interstitialis from the locality of El Salón. As part of the current study both host species were collected from El Salón. In all the examined specimens of P. interstitialis only L. similis was found. On the other hand, L. longior was present in the A. pertyi specimens. Such results have been observed in the rest of the localities studied across the Cuban archipelago. We conclude that both Longior species present some host specificity: L. longior is associated with A. pertyi and L. similis with P. interstitialis . Thus, it is possible that the records of Coy (1990) and Coy et al. (1993) could be attributed to host misidentification.

Figures

FIGURE 1. Longior longior Morffe & García, 2011. Female. A. Oesophageal region, ventral view. B. Tail, ventral view. C. Cephalic end, optical section.D. Cephalic end, externalview (reconstructed from SEM images). E. Cephalic end, en face view (reconstructed from SEM images).F.Genital tract, ventral view.G.Egg. H. Habitus, ventral view.

FIGURE 2. Longior longior Morffe & García, 2011. Male. A. Oesophageal region, lateral view. B. Cephalic end, optical section. C. Cephalic end, external view (reconstructed from SEM images). D. Cephalic end, en face view (reconstructed from SEM images).E. Tail, lateral view.F.Tail end, lateral view (reconstructed from SEM images).G.Habitus, lateral view.

FIGURE 3. Longior longior Morffe & García, 2011. Female, SEM images. A. Habitus, lateral view. B. Cephalic end and cervical region. C. Cephalic end. D. Cephalic end, en face view.E. Vulva, ventro-lateral view. F. Anus and end of lateral alae, lateral view. Scale bars:A. 1 mm.B.40 µm. C. 20 µm. D. 10 µm. E, F.50 µm.

FIGURE 4. Longior longior Morffe & García, 2011. Male, SEM images. A. Habitus, lateral view. B. Cervical region. C. Cephalic end. D. Cephalic end, en face view. E. Tail, lateral view. F. Tail end, lateral view. G. Tail end, fronto-lateral view. H. Tail end, frontal view.I. Ventro-median pair of pre-cloacal papillae.Scale bars:A. 500 µm. B, E. 50 µm. C.30 µm. D, I. 5 µm. F.20 µm. G. 10 µm. H. 15 µm.