Kerkophorus piperatus, Herbert, 2017

Herbert, David G., 2017, A new genus and eight new species of tail-wagger snails from eastern South Africa, with a key to genera within Sheldonia s. l. (Gastropoda: Urocyclidae), European Journal of Taxonomy 309, pp. 1-50 : 5-11

Kerkophorus piperatus sp. nov.

urn:lsid:zoobank.org:act:34727BE3-D632-4478-ADEE-0C816F23244F

Figs 2–6

Sheldonia inuncta (non Melvill & Ponsonby, 1899) – Connolly 1939: 145 (in part). — Herbert & Kilburn 2004: 264 (in part), un-numbered figure.

Diagnosis

Characterised by the combination of moderate size, silky surface and red-brown spiral line situated well above mid-whorl, together with the generally brownish colour of the animal, dark speckling of the pulmonary lining and the absence of a stimulator in the genital atrium.

Etymology

From the Latin ' piper, piperatus ’, pepper, peppered; referring to the speckled black and cream pigmentation of the pulmonary lining visible through the shell.

Material examined

Holotype

SOUTH AFRICA: KwaZulu-Natal, Makowe , 27.9617° S, 32.1179° E, ± 500 m, J. Crosly leg. ( NMSA A8172/T4057 , shell only).

Paratypes (listed north to south)

SOUTH AFRICA: Mpumalanga: Mariepskop Forest, 24.55952° S, 30.88760° E, 1420 m, indigenous Afromontane forest, in leaf-litter, J. Horn leg., 28 Feb. 2005 ( NMSA W4433/T4050, three dry shells with bodies in ethanol, plus one whole specimen in ethanol); Mariepskop Forest, 24.563° S, 30.863° E, 1400 m, indigenous Afromontane forest, A.C. and W.H. van Bruggen leg., 29 Jan. 1966 ( NMSA W3652/T4048, one dry shell with body in ethanol); Mariepskop Forest, 24.56374° S, 30.86293° E, 1640 m, northern mistbelt forest, in leaf-litter, D. Herbert, L. Davis and M. Cole leg., st. 14-22, 3 Dec. 2014 ( ELM D18023/T152, two dry shells); Mariepskop Forest, 24.56683° S, 30.86232° E, 1520 m, indigenous Afromontane forest, in leaf-litter, J. Horn leg., 28 Feb. 2005 ( NMSA W3717/T4053, 15 dry shells with bodies in ethanol, plus 10 whole juveniles in ethanol); Mariepskop Forest, Bushpig Trail, 24.56694° S, 30.86270° E, 1491 m, mistbelt forest, A. Moussalli and D. Stuart-Fox leg., 15 Dec. 2006 ( NMSA W6002/T4052, one dry shell); Mariepskop Forest, Picnic Trail, 24.56847° S, 30.85920° E, 1545 m, northern mistbelt forest, in leaf-litter, D. Herbert, L. Davis and M. Cole leg., st. 14-27, 4 Dec. 2014 ( NMSA P0229/ T 4051, 1 dry shell with body in ethanol); Mariepskop Forest, M. Cole leg., 18 Oct. 2010 ( NMSA W 9365/ T 4049, one dry shell with body in ethanol); Mariepskop Forest, on slope of escarpment, 24.570932° S, 30.860407° E, 1514 m, M. Cole leg., 18 Oct. 2010 ( ELM D16958/ T 038, one dry shell). — KwaZulu-Natal: Ngome Forest, 27.824405° S, 31.419130° E, 1136 m on Clivia, W. Haselau leg., 15 Jun. 2010 ( ELM W 3683/ T 153, whole specimen in ethanol); Ngome Forest, 27.850° S, 31.383° E, 800–1300 m, mistbelt and coastal scarp sections of forest, mostly under logs, occasionally also on understorey vegetation and bark, D. Herbert leg., Dec. 1995 ( NMSA V 2250 / T 4056, 13 dry shells with nine bodies in ethanol, plus seven whole specimens in ethanol); same data as holotype ( NMSA A 8173/ T 4058, two dry shells); Hluhluwe Game Reserve, 28.04° S, 32.10° E, 170 m, forest patches in bushveld, in leaf-litter, D. Herbert leg., 2 Jan. 1996 ( NHMUK 20160240, one dry shell; NMSA V 2360 / T 4055, six dry shells with four bodies in ethanol); Hluhluwe Game Reserve, Mbombe Forest, 28.05654° S, 32.05045° E, 532 m, scarp forest, A. Armstrong and A. Gomez leg. ( EKZNW 341146), 6 Oct. 2011 ( NMSA W 9644/ T 4054, one dry shell with body in ethanol, plus one whole specimen in ethanol); Hluhluwe Game Reserve, 28.067° S, 32.040° E, 450 m, scarp forest, on tree trunks, D. Herbert leg., 31 Dec. 1995 ( NMSA V 2279 / T 4059, three dry shells with two bodies in ethanol; RMNH.5004183, one dry shell).

Other material (listed north to south, NMSA)

SOUTH AFRICA: Mpumalanga: Mariepskop Forest, 24.56353° S, 30.86252° E, 1620 m, indigenous Afromontane forest, 3 m above ground in epiphytes of standing tree, J. Horn leg., 22 May 2005 ( W 3680); Mariepskop Forest, 24.56374° S, 30.86293° E, 1640 m, northern mistbelt forest, in leaf-litter, D. Herbert, L. Davis and M. Cole leg., st. 14-22, 3 Dec. 2014 ( P 0277); Mariepskop Forest, 24.56708° S, 30.8599° E, 1540 m, Afromontane forest, in leaf-litter, J. Horn leg., 24 Nov. 2005 ( W 3906). — KwaZulu-Natal: Ngome Forest, 27.8017° S, 31.4376° E, mistbelt forest, active on understorey foliage, A. Moussalli and D. Stuart-Fox leg., 8 Jan. 2004 ( W 3309); Ngome Forest, Ntendeka Wilderness Area, 27.80177° S, 31.43765° E, mistbelt forest, on understorey foliage, A. Moussalli and D. Stuart-Fox leg., 8 Jan. 2004 ( W 5035); Ngome Forest, 27.8370° S, 31.3917° E, 1200 m, mistbelt Podocarpus forest, in leaf-litter, D. Herbert, M. Seddon and P. Tattersfield leg., 2 Dec. 1998 ( V 8553); Hluhluwe Game Reserve, 28.05278° S, 32.05327° E, 568 m, forest, A. Armstrong leg. ( EKZNW 323534), 30 Sep. 2002 ( W 7301); Hluhluwe Game Reserve, Mbombe Forest, 28.056539° S, 32.050450° E, 532 m, scarp forest, A. Armstrong and A. Gomez leg. ( EKZNW 341146), 6 Oct. 2011 ( W 9644); Hluhluwe Game Reserve, 28.06377° S, 32.04388° E, 450 m, forest, under log, A. Armstrong and P. Sokhela leg. ( EKZNW No. 478152), 28 Oct. 2013 ( W 9760); Hluhluwe Game Reserve, in forest between research st. and perimeter fence, 28.07360° S, 32.03909° E, 460 m, scarp forest, D. Herbert leg., 12– 14 Jan. 1995 ( V 580); Hluhluwe Game Reserve, 28.075° S, 32.055° E, 400 m, scarp forest, in leaf-litter, D. Herbert, M. Seddon and P. Tattersfield leg., 30 Nov. 1998 ( V 7664); Hluhluwe Game Reserve, 28.077° S, 32.045° E, 460 m, scarp forest, in leaf-litter, D. Herbert, M. Seddon and P. Tattersfield leg., 29 Nov. 1998 ( V 7679); Hluhluwe Game Reserve, Hilltop Camp walk, 28.0830° S, 32.0417° E, 400 m, scarp forest, in leaf-litter, D. Herbert leg., 31 Dec. 1995 ( V 2162); Hlabisa, 28.145° S, 31.882° E, ± 540 m, H. C. Burnup leg., pre 1928 ( A 8174).

Description

SHELL ( Fig. 2 ). Lenticular to globose-lenticular; periphery at mid-whorl, evenly rounded; shell proportions variable, H:D 0.61–0.74 (N=15); suture shallowly indented, inserting well above periphery; thin, translucent, straw-buff when fresh, fading to pale buff, with a thin red-brown line level with suture and obscured by it on spire whorls; surface silky and lacking lustre. Protoconch diameter 1.65–1.90 mm (N=17); junction with teleoconch usually weakly marked; essentially smooth, but bearing faint, closeset, microspiral sculpture. Teleoconch of up to 3.3 whorls; coiling relatively tight, whorls not expanding rapidly; sculptured by weak growth-lines and exceptionally fine and close-set, microscopic spiral lines, slightly finer than those on protoconch; later whorls also with microscopic axial sculpture of a similar nature, giving surface its lustreless sheen. Umbilicus patent but narrow, mostly obscured by reflected upper portion of columella lip. Aperture roundly and obliquely lunate. Diameter up to 18.8 mm; holotype, diameter 18.6 mm, height 11.4 mm; specimens from Mpumalanga somewhat smaller ( Fig. 2G ), maximum diameter 14.0 mm.

LIVING ANIMAL ( Fig. 3 ). Head-foot pale greyish-brown, neck and posterior of foot usually slightly darker; optic tentacles and their retractor muscles darker grey; body lobes of mantle of similar coloration to head-foot; shell lobes well developed, slender and elongate; caudal appendage dark grey; much of body, particularly the neck, body lobes of mantle and posterior of foot with microscopic cream or pale orange pigment granules. Lining of pulmonary cavity speckled, sometimes heavily so, with irregular black and cream blotches and spots; portion overlying reno-pericardial area cream with a distinct horizontal black band; mantle margin beneath outer lip of shell bordered by a narrow cream line. Spire viscera darker brown with scattered irregular cream markings.

RADULA ( Fig. 4 ). Formula R+14+(1–2)+(60–70); rachidian tricuspid, anterior margin of shaft base shallowly indented; laterals essentially bicuspid with a mesocone and strong basal ectocone, but also with a minute endocone on side of mesocone; laterals followed by 1–2 teeth of intermediate shape and then a long series of marginals; marginals curved and bicuspid, with a large terminal cusp with a slightly

smaller subterminal one on outer (concave) margin; shaft lacking serrations; marginals progressively decreasing in size toward edge of radula, but otherwise morphologically similar.

DISTAL GENITALIA ( Fig. 5 A–B). Penis encased in thin sheath and usually with a distinct S-shaped bend in basal half, sometimes another in apical half; retractor muscle attached to penis apex; base of penis defined by fusion with sheath and constriction of lumen; penis base may bulge into preputial region joining penis base to atrium; internally penis divided into two sections, basal third rather thin-walled, with two longitudinal ridges and lined throughout by microscopic papillae, apical two-thirds thickerwalled with more numerous, smooth longitudinal folds; junction between sections delimited by a slight constriction, but no verge evident in this region. Epiphallus very short; caecum well developed, considerably longer than epiphallus, cylindrical, but somewhat sinuous, distal portion slightly broader, with bluntly rounded apex; caecum lined internally with a complex lattice of interconnected folds and lumen largely obstructed; distal portion of caecum compartmentalised and sometimes with chalky contents; caecum arising very close to penis apex and insertion of retractor muscle; epiphallus, caecum and penis apex forming a triple junction. Basal part of flagellum (f1) stout, comprising ± 1 whorl, with distinct transverse internal structure; f2 slender, longer than f1, straight in some specimens, variously curved in others; little evidence of chalky material inside proximal epiphallus; vas deferens simple and slender. Genital atrium simple, lacking stimulator, its lining comprising an oblique latticework of narrow interconnected ridges; vagina short; gametolytic sac thin walled and irregularly pyriform, its duct of moderate length; base of free oviduct swollen, dark (brown/black) in fresh material; spermoviduct divided into distinct prostatic and oviductal portions.

SPERMATOPHORE ( Fig. 5C ). Elbowed, with a crescent-shaped capsule (length approx. 4.7 mm) and a long coiled tail; proximal part of tail bearing two rows of stout branching spines spiralling around tail; primary row extending for approx. one coil; spines in mid-region larger and more complexly branched; a shorter, secondary row of approx. 10 spines on opposite side of proximal part of spinose region, these initially similar to those of primary row, but distal ones with progressively fewer branches; spines of primary row flabellate, terminating in deeply V-shaped bifurcations, their tips slender and pointed, not or at most weakly curved; distal half of tail lacking spines, very slender and variously curved or coiled.

Distribution ( Fig. 6 )

Endemic to north-eastern South Africa (and probably also Swaziland), ranging from the coastal escarpment of north-eastern KwaZulu-Natal to the Drakensberg of northern Mpumalanga; at altitudes between 170 m and 1640 m above sea level.

Habitat

Scarp Forest and both Southern and Northern Mistbelt Forest ( Mucina & Rutherford 2006); mostly in leaf-litter, under logs and low down on tree trunks, but occasionally on understorey vegetation.

Remarks

This and the following species have until now been confused with Kerkophorus inunctus (Melvill & Ponsonby, 1899) and were usually identified under that name ( Connolly 1939; Herbert & Kilburn 2004). Kerkophorus piperatus sp. nov., however, has a more elevated shell than K. inunctus , less rapidly expanding whorls and does not attain such a large size (max. diameter 19 mm vs 25 mm). In addition, the present species lacks the large stimulator in the genital atrium that is found in both K. inunctus and K. vittarubra sp. nov. (below). In the field, the generally brownish colour of K. piperatus sp. nov., its silky shell and the dense dark speckling of the pulmonary lining are distinctive features. In K. inunctus the pulmonary lining lacks black speckling and the spire viscera exhibit much yellowishwhite pigmentation. Additional comments are given below in the remarks for K. vittarubra sp. nov.

The apparent hiatus in the known range of the species, between the KwaZulu-Natal population and that in northern Mpumalanga, is almost certainly an artefact stemming from insufficient field surveys.

Conservation

Kerkophorus piperatus sp. nov. is a relatively widespread species and it is known to occur in a number of formal conservation areas (Hluhluwe Game Reserve, Ngome State Forest and Mariepskop State Forest). Provided that the integrity of these habitats is preserved, they will provide a degree of security. However, the preservation of indigenous forest in western Swaziland is also likely to be important for the conservation of this species, if future field research demonstrates its occurrence in this region.

Figures

Fig. 2. Kerkophorus piperatus sp. nov. A–D. Holotype, diameter 18.6 mm (NMSA A8172/T4057). E. Hluhluwe Game Reserve, KwaZulu-Natal, diameter 18.4 mm (paratype, NMSA V2360/T4055). F. Ngome Forest, KwaZulu-Natal, diameter 18.8 mm (paratype, NMSA V2250/T4056). G. Mariepskop, Mpumalanga, diameter 13.0 mm (paratype, NMSA W9365/T4049). H. Possible K. piperatus × vittarubra hybrid, Nkandla Forest, KwaZulu-Natal, diameter 18.8 mm (NMSA W1116).

Fig. 3. Kerkophorus piperatus sp. nov., living animals. A. Hluhluwe Game Reserve, KwaZulu-Natal, shell diameter 16.0 mm (paratype, NMSA V2279/T4059). B. Mariepskop, Mpumalanga, shell diameter 13.3 mm (paratype, NMSA P0229/T4051).

Fig. 4. Kerkophorus piperatus sp. nov., radula (paratype, NMSA V2250/T4056). A. Rachidian and left lateral teeth. B. Rachidian and innermost lateral teeth. C. Inner right marginal teeth. D. Outer right marginal teeth. Scale bars = 100 μm.

Fig. 5. Kerkophorus piperatus sp. nov., genitalia and spermatophore. A–B. Genitalia, Mariepskop, Mpumalanga (paratype, NMSA W4433/T4050). A. Entire genital tract. B. Dissection of genital atrium and penis sheath. C. Spermatophore, Mariepskop, Mpumalanga (NMSA W3906).

Fig. 6. Distribution of Kerkophorus piperatus sp. nov. (triangles), Kerkophorus vittarubra sp. nov. (squares), and Microkerkus sibaya sp. nov. (cross). The population at Nkandla marked ‘?’ is a potentially hybrid population with shell characters resembling K. piperatus sp. nov., but with genitalia resembling K. vittarubra sp. nov. Contours at 1000 and 1500 m.