Squatinella longipila, Luo & Segers, 2020

Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa’s rotifers, Zootaxa 4731 (3), pp. 371-387 : 382

Squatinella longipila n. sp.

Figures 2 a–c, I-2

Type locality. Yangambi primary forest, DR Congo, 11 June 2012 (Y27) ; a single specimen from Lohulu River near Bomane, DR Congo 24 May 2010 ( KM28 ) .

Material examined. Holotype: One female specimen in permanent slide, deposited in RBINS ( RIR.339) ; Paratypes: three permanent slides containing one female specimen each, deposited in RBINS ( RIR.340 to RIR.342) ; two permanent slides containing one female specimen each, CSB-UK; one paratype in SHNU .

Differential diagnosis. This relatively small Squatinella appears related to S. longispinata , by having a foot with three separate foot pseudosegments and separate toes. It differs from that species by lacking an additional spine overlaying the toes, and by its extremely long dorsal spine, reaching more than twice the total body length (including foot).

Differential diagnosis. Parthenogenetic female (male unknown): Body elongated, separated in a head, trunk, and foot region, lorica relatively soft but body shape rather constant. Head bearing a semi-circular head shield covering the homogeneous corona; lateral projections of the posterior corona region present, set-off from trunk by a weakly constricted neck. Trunk elongated, ventrally relatively flat, with a transverse fold in the distal third, dorsally with a middorsal, strongly elongated, almost hair-like and terminally pointed spine; this spine with an elongate triangular basis, slightly bent backwards just posterior of the triangular basis, and smoothly curved towards distally. Spine movable from erect to dorsad, parallel to the body axis, overlaying the foot. Vitellarium extending into the basis of the dorsal spine. Terminal part of the trunk falling to the foot. Foot with three separated foot pseudosegments, the second and third about as long and twice as long as the first, third foot pseudosegment bearing a sensory groove dorsally about medially. Two separate, elongate triangular toes.

Measurements (n=6). Total length (including foot): 117–130 (122), height: 37–51 (46), foot length: 18–20 (19), toe: 7–9 (7), spine length: 251–303 (278), ratio dorsal spine: body length: 1.94–2.57(2.35)

Etymology. The specific name is an adjective, derived from the Latin words “ longus ” (long) and “ pilus ” (a single hair), and refers to the exceptionally elongate dorsal spine that resembles a long, single hair, on the animal’s back.

Distribution. In addition to the Congo records, this species may occur in Thailand ( S. leydigii after Chittapun et al. (1999: Figure 6 )) and Cambodia ( S. leydigii after Sor (2011: Figure 18g), from a reservoir in Krang Deisor, Stung Treng province).

Figures

FIGURES 1–4. Lepadellidae, line drawings. Figure 1a–b: Squatinella curviseta n. sp., a: habitus, lateral (scale bar: 100µm); b: detail of foot, lateral (scale bar: 50µm). Figure 2a–c: Squatinella longipila n. sp., habitus. a: detail, body (scale bar: 50µm); b–c: complete specimens (scale bar: 50µm). Figure 3a–c: Colurella asymmetrica n. sp. a: caudal region and foot, left; b: habitus, right; c: habitus, ventral view. Figure 4: Colurella uncinata bicuspidata: habitus, right (3, 4: scale bar: 50µm).

FIGURE 5–9. Lepadella spp., line drawings. Figure 5a–c: Lepadella hanneloreae n. sp., habitus. a: ventral; b: dorsal; c: frontal. Figure 6a–c: Lepadella jingruae n. sp., habitus. a: ventral; b: lateral; c: frontal. Figure 7a–c: Lepadella weijiai n. sp., habitus. a: ventral; b: dorsal; c: frontal. Figure 8a–c: Lepadella yangambi n. sp., habitus. a: ventral; b: dorsal; c: lateral; d: caudal. Figure 9a–c: Lepadella wilungulai n. sp., habitus. a: ventral; b: dorsal; c: frontal. (all scale bars: 50µm).