Setosabatieria longiapophysis, Guo & Huang & Chen & Wang & Lin, 2015

Guo, Y. Q., Huang, D. Y., Chen, Y. Z., Wang, J. J. & Lin, R. C., 2015, Two new free-living nematode species of Setosabatieria (Comesomatidea) from the East China Sea and the Chukchi Sea, Journal of Natural History 49 (33), pp. 2021-2033 : 2022-2026

Setosabatieria longiapophysis sp. nov. ( Figures 1, 2 and Table 1)

Type material

Five males and two females were collected from station XMGLY L2 . Holotype: ♂ 1 on slide number XMGLY 20111016 L206.

Paratypes: ♂ 2 and ♀ 2 on slide number XMGLY 20111016 L205, ♂ 3 on XMGLY 20111016 L210, ♂ 4 on XMGLY 20111016 L218, ♂ 5 and ♀ 1 on XMGLY 20111016 L213.

Type locality and habitat

Intertidal sandy sediment at Gulang Island , Xiamen, the East China Sea. Latitude: 118.0666°E, longitude: 24.4333°N.

Characteristics of surface sediment: Silt + clay 0.07%, salinity 20 – 22 ‰, total organic matter 0.0192%.

Etymology

This species is named for the long straight apophyses of gubernaculum.

Measurements

Measurements are given in Table 1.

– 252 W 2273 Holotype ♂ 1: 16 41 49 39 2480 µm; a = 50.6, b = 9.8, c = 12.0, Spic = 66.0 µm

– 270 V 2312

Paratype ♀ 1: 2540 µm; a = 49.8, b = 9.4, c = 11.2, V % = 50.0%

16 41 51 38

Description

Body cylindrical, tapering towards both extremities, maximum body diameter 42 – 58 µm. Cuticle not punctate but with faint transverse striations visible throughout body. Head narrower than rest of body due to constriction at level of amphidial fovea. Buccal cavity cup-shaped. Inner labial sensilla not visible, outer labial sensilla setiform, 2 μm long. Four cephalic setae 16 – 19 µm long (100 – 120% of head diameter). Cervical setae, similar to cephalic setae length, arranged in four longitudinal files of seven to nine setae. Amphidial fovea spiral, with 2.75 – 3 turns, 15 – 17 µm in diameter, occupying 49 – 69% of corresponding body diameter. Pharynx gradually enlarging posteriorly but without true terminal bulb. Nerve ring at 61 – 65% of pharynx length from anterior end. Cardia small, muscular, surrounded by intestinal tissue. Excretory pore posterior to nerve ring. Tail conico-cylindrical, 5.3 – 6.0 times anal body diameter, with numerous caudal setae. Tail tip enlarged with three terminal setae 12 µm long. Caudal glands and spinneret well developed.

Males. Testes opposite and outstretched. Anterior testis situated to left of intestine, posterior testis to right. Spicules paired, equal, arcuate, with slightly marked capitulum and a central cuticularized septum at the proximal end. Gubernaculum with 31 – 37 µm long straight dorsocaudal directed apophyses. Fifteen or 16 poorly developed small precloacal papillate supplements, posterior supplements with closer spacing.

Females. Similar to male in general characteristics, but amphid diameter smaller; vulva at 49 – 50% of total body length but developed reproductive system not found.

Differential diagnosis

Setosabatieria longiapophysis sp. nov. is similar to Setosabatieria triangularis Riera et al. 2006 in that they both have longer cephalic setae than in the other species, and a similar number of cervical setae in each sublateral row and precloacal supplements ( Table 3). However, Setosabatieria longiapophysis sp. nov. has spicules with straight apophyses 31 – 37 µm long in contrast to the triangular apophyses of S. triangularis .

Figures

Figure 2. Setosabatieria longiapophysis sp. nov. (A) lateral view of male head end, showing amphidial fovea and cephalic setae; (B) lateral view of female head end; (C) lateral view of female vulva region; (D) lateral view of male head end, showing cervical setae; (E) lateral view of male spicule, gubernaculum and precloacal supplements. Scale bars: A–C = 10 µm, D, E = 50 µm.