Telotylenchus paaloofi Tikyani & Khera, 1970

Ghaderi, Reza, Karegar, Akbar, Miraeiz, Esmaeil & Hashemi, Kobra, 2017, Comparative morphology of the anterior end of selected taxa of Merliniidae Siddiqi, 1971 (Nematoda: Tylenchoidea), with morphological characterisation of two species and taxonomic keys to several genera, Zootaxa 4300 (4), pp. 571-588 : 583-584

Telotylenchus paaloofi Tikyani & Khera, 1970

( Figs 7 & 8 )

Measurements. See Table 2.

Female. Body almost straight to slight ventrally curved after fixation. Cuticle annuli about 1 µm wide at midbody. Each lateral field with four incisures near mid-body, not areolated; 30–38 % of the corresponding body diameter. Lip region hemispherical, offset from the body by a distinct constriction, 4–5 µm high and 7–8 µm wide at base; with six or seven distinct annuli. Perioral disc slightly raised on lip region and cephalic framework moderately developed. Stylet robust, 2.6–2.8 times the cephalic region diameter at base, conus 10–11 µm and about half of the stylet; basal knobs directed slightly backward. Dorsal pharyngeal gland orifice 1–2 µm from stylet base. Median bulb rounded to slightly oval, 83–91 µm from anterior end. Nerve ring situated slightly anterior to the middle of the isthmus, 117 µm from the anterior end. Hemizonid three annuli wide, five annuli anterior to secretory-excretory pore. Deirids were not observed. Pharyngeal glands elongated, extending over intestine laterally by 2–3 times of the corresponding body diameter. Pharyngo-intestinal valve pyriform, usually shifted centrally. Intestinal fasciculi inconspicuous. Vulva a transverse slit, cuticle around vulval region with normal thickness; vagina shorter than half of the corresponding body diameter, spermatheca indistinct. Post-anal intestinal sac absent. Tail broadly conical, with rounded and annulated terminus. Phasmids 22 µm posterior to anus, near middle of tail.

Male. Not found.

Remarks. The morphological and morphometric characters of our population fit well with those of T. paaloofi from India ( Tikyani & Khera, 1970), except for having a slightly shorter tail (46–47 vs. 56 µm; c' = 2.5–2.8 vs. 3– 4) and a longer pharynx (134–141 vs. 115 µm). Our population also shares several characters with T. avaricus Kleynhans, 1975 , T. brevicaudatus Mirzoyants, 1996 , T. elongatus Sultan, Singh & Sakhuja, 1989 , T. flaccidus Baydulova, 1984 and T. ventralis Loof, 1963 , but can be separated from these by differences in certain diagnostic characters: our Iranian population differs from T. avaricus in having a longer body (984–1039 vs. 630–740 µm) and non-areolated lateral field (vs. all three bands areolated). In our population, the tail is broadly conical with annulated terminus and 26–32 ventral annuli, while T. brevicaudatus has a sharply conical tail with smooth terminus and 16–20 ventral annuli. T. elongatus , has a shorter body (720–750 µm), fewer head annuli (5–6) and smooth tail terminus. In T. flaccidus , the stylet is slightly shorter (17.5–19 vs. 20–21 µm), the tail has more ventral annuli (42–57 vs. 26–32), and the cuticle is thickened around vulva (vs. undifferentiated). Our population can be distinguished from T. ventralis by its annulated (vs. smooth) tail terminus and 26–32 tail annuli (vs. 48–52). Also, the stylet is slightly shorter (16–19 µm) and the lateral field is areolated in T. ventralis .

This population was collected many years ago by the well-known nematologist, Dr. Dieter Sturhan, from the rhizosphere of an unknown plant in Ahvaz county , Khuzestan province, south-western Iran . Sturhan (1974) listed 26 genera of plant-parasitic nematodes, including Telotylenchus , from Iran, but identification to species level was not undertaken in that survey. The present study reports the first species of the genus Telotylenchus from Iran.

Figures

FIGURE 7. Females of Telotylenchus paaloofi: A. Reproductive system; B. Cuticle and lateral field; C. Anterior end; D – F. Pharyngeal region; G. Tail. Scale-bars: A = 100 µm; B, C, G = 20 µm; D – F = 50 µm.

FIGURE 8. Females of Telotylenchus paaloofi: A – D. Anterior end; E – H. Pharyngeal region; I. Entire body; J & L & M. Tails; K. Lateral field. Scale-bars: A – D, K – M = 10 µm; E – H, J = 20 µm; I = 100 µm.