Pseudamnicola (Corrosella) luisi Boeters, 1984

Delicado, Diana, Machordom, Annie & Ramos, Marian A., 2011, Underestimated diversity of hydrobiid snails. The case of Pseudamnicola (Corrosella) (Mollusca: Caenogastropoda: Hydrobiidae), Journal of Natural History (J. Nat. Hist.) 46 (1 - 2), pp. 25-89 : 31-36

Pseudamnicola (Corrosella) luisi Boeters, 1984

Pseudamnicola luisi Boeters, 1984: 9 ,10, figs. 1, 2.

Type locality

Lapeza, Granada VG 72 ( Boeters 1984).

Material examined

Type material. Holotype SMF 256 391 , Paratype BOE 224 , Slg Falkner and RMNH Leiden, Slg. Altimira ( Boeters 1984).

Topotypes. Boeters (1984) only cited Lapeza, Granada as the type locality. We found the species in La Gitana spring in La Peza (= Lapeza), Granada, UTM: 30S 047415/412475. This is most probably the type locality because this spring is the freshwater habitat closest to La Peza within the 10 × 10 km VG72 UTM grid mentioned by Boeters (1984), although he used the Military Grid Reference System. The description of this species has therefore been based on this topotypical material collected in different years and deposited in the MNCN collections under MNCN 15.05/49147, MNCN 15.05/49148, MNCN 15.05/49149, MNCN /ADN 34827–34830, MNCN /ADN 34827–34830, MNCN 15.05/49150.

Other populations examined. In addition to La Gitana spring, this species has only been found in a few localities in the centre of Granada province ( Figure 1 ). Boeters (1984, 1988) cited the species also in Almería province ( WF 79 el Moltés, Níjar, Rijksmuseum van Natuurlijke Historie Leiden, Slg. Altimira, Pseudamnicola brevispira ), although he included no drawings of specimens from this province. We have found no specimens of this species in Almería. Specimens of all localities mentioned in the following section were also morphologically examined.

Localities. La Gitana spring in La Peza, Granada, UTM: 30S 047415/412475, D.M. and E.R., 27 September 1989, MNCN 15.05 /49147 (70% ethanol); B.A., 25 March 1998, MNCN 15.05 /49148 ( ESEM preparation, Figures 2A,C–F , 3 and 70% ethanol, Figure 4 ); D.D., 12 May 2007, MNCN 15.05 /49149 (absolute ethanol) and MNCN / ADN 34827–34830 (frozen material and absolute ethanol); JM.B., 12 March 2009, MNCN 15.05 /49150 (70% ethanol); Fuente Grande in Diezma , Sierra Harana, Granada, UTM: 30 S 04592 /41308, D.M., 23 April 1992, MNCN 15.05 /49151 (70% ethanol); B.A., 25 March 1998, MNCN 15.05 /49152 (70% ethanol); JM.B., 22 August 2006, MNCN 15.05 /49153 (96% ethanol) and MNCN /ADN: 34834–34837 (96% ethanol); MA.R., 7 May 2008, MNCN 15.05 /49154 (70% ethanol); Polvorista stream, Quéntar, Granada, UTM: 30S 0465250/4122700, JM.B., 27 October 2006, MNCN 15.05 /49155 (96% ethanol and ESEM preparation, Figure 2B ) and MNCN / ADN 34831–34833 (96% ethanol); La Teja spring in Sierra de Huétor , Granada, UTM: 30S 0455050/4124207, JM.B., 30 September 2008, MNCN 15.05 /49156 (96% ethanol) and MNCN / ADN 34838–34840 (96% ethanol); La Grea stream, Maitena, Granada, UTM: 30 S 04616 /41127, D.M. and E.R., 27 September 1989, MNCN 15.05 /49157 (70% ethanol); ditch in Sierra de Huétor, Granada, UTM: 30S 0495820/4129400, JM.B., 22 August 2006, MNCN 15.05 /49158 (96% ethanol) and MNCN /ADN 34841 (96% ethanol); Fardés spring in Diezma, Sierra Harana, Granada, UTM: 30 S 04592 /41308, D.M. and E.R., 12 October 1992, MNCN 15.05 /49159 (70% ethanol); Fuente Grande in Prado Negro, Granada, UTM: 30S 045/416, JM.B., 25 May 2006, MNCN 15.05 /49160 (96% ethanol) and MNCN / ADN 34842–34846 (96% ethanol) .

Material examined for morphometry. Shell, anatomical, operculum and radular measurements (Appendix Tables 1–8) taken from topotypes from La Gitana spring in La Peza, Granada. Males and females examined were collected in the months March, May and September.

Diagnosis

Shell with whitish or greyish periostracum; tall ctenidial filaments; central tooth of radula with three wide lateral cusps at each side; black pigmentation on anterior chamber of stomach and intestine; pyriform bursa copulatrix U-shaped; elongated seminal receptacle; renal oviduct black pigmented until loop; slender penis with a large patch of pigmentation on its distal region; nervous system black pigmented, ganglia darker than connectives; supraoesophageal connective at least four times longer than suboesophageal.

Description

Shell ovate-conic ( Figure 2A,B ) with 4–5.5 spire whorls, height 3.5–5 mm ( Figure 2A,B,D ; Appendix Table 1), periostracum whitish or greyish; protoconch approximately 500 µm in width with 1.5 whorls and a nucleus around 170 µm long ( Figure 2D,E ); protoconch microsculpture moderately granulated ( Figure 2F ); body whorl about two-thirds total length and penultimate whorl relatively taller than previous ones; teleoconch whorls moderately convex with a deep suture; peristome orthocline; inner lip of aperture thicker than outer lip and partially hiding the umbilicus; peristome margin simple, straight ( Figure 2C ).

Operculum with around 3.5 spire whorls and muscle attachment area oval located near the nucleus ( Figure 3A,B ; Appendix Table 2).

Radula intermediate length (20% total shell length) and approximately eight times longer than wide ( Figure 3C , Appendix Table 4); bears some 51 rows of teeth; central tooth with a tongue-shaped median cusp and three wide lateral cusps at each side slightly sharpening towards median cusp ( Figure 3D,E ); lateral teeth with two tapered cusps at each side of central tongue-shaped cusp; inner marginal teeth have 12 sharp cusps, shortening towards the base of tooth; outer marginal teeth with 15 tapered cusps ( Figure 3D,F ).

Pigmentation and anatomy. Head dark brown pigmented from snout to neck ( Figure 4F ); pigmentation is clearer on neck; tentacles also brown pigmented but not ocular lobes; snout as long as wide, with medial lobation; foot of intermediate length, pigmented in dorsal region. Ctenidium in the anterior region of pallial cavity with 20–24 large gill filaments taller than wide; osphradium of intermediate width under central gill filaments ( Figure 4C , Appendix Table 3). Stomach slightly longer than wide with two chambers equal in size ( Figure 4E ); the anterior chamber could display a small patch of black pigmentation; long gastric caecum; style sac longer than wide surrounded by black pigmented intestine (Appendix Table 5).

Female genitalia with a slender pallial oviduct containing two glands approximately equal in size ( Figure 4G ; Appendix Table 6); capsule gland more transparent than albumen gland in the specimens studied; bursa copulatrix pyriform, long, folded and U-shaped with a duct less than 50% bursa length; renal oviduct white straight from the insertion point of bursal duct to where it begins to fold and black pigmented making a simple loop, hereafter undulating; seminal receptacle elongated with short duct ( Figure 4H ) joining renal oviduct slightly above the point where the bursal duct joins the renal oviduct; there is no contact between distal end of bursa copulatrix and distal end of seminal receptacle.

Male genitalia bears a two or three times longer than wide prostate gland (Appendix Table 7) with an efferent duct entering the medial region and deferent duct emerging at its anterior edge ( Figure 4D ); penis, long slender, with a blunt distal end and a large patch of pigmentation distally; base of intermediate width attached to the central head area with some folds in its middle region ( Figure 4F ); penial duct scarcely visible running straight close to the outer penis margin.

Nervous system black pigmented, but ganglia darker than connectives and commissures; cerebral ganglia equal in size; supraoesophageal ganglion around two times longer than suboesophageal and supraoesophageal connective approximately five times longer than suboesophageal ( Figure 4A,B ; Appendix Table 8). Mean RPG ratio 0.41 (moderately concentrated).

Remarks

Among the Pseudamnicola , P. (C.) luisi is the largest species, measuring about 5 mm in height. All specimens showed signs of erosion, not only on the protoconch as in other species, but all over the shell surface.

Pseudamnicola (C.) marisolae sp. nov., P. (C.) iruritai sp. nov. and P. (C.) andalusica sp. nov. are sister species (see Figure 26 ), belonging to the same clade as P. (C.) luisi but not as large. These four species share slender shells, a high SL/SW value (Appendix Table 1), long penis with a large patch of pigmentation, long prostate gland and one seminal receptacle with a short duct. Pseudamnicola (C.) marisolae sp. nov. is molecularly the closest and also biogeographically the nearest species to P. (C.) luisi . The two species share characteristics such as: same number of cusps on lateral and inner marginal teeth, same number of gill filaments, same length of connectives in nervous system and similar shape of penis and bursa copulatrix. Pseudamnicola (C.) luisi differs from the rest of the species of this clade in its granulate protoconch microsculpture, long gill filaments, longer pallial oviduct, larger penis and shell aperture than the rest of species, lack of pigmentation of distal section of renal oviduct and seminal receptacle and the lowest RPG ratio. All these characters serve also to differentiate P. (C.) luisi from P. (C.) falkneri , P. (C.) manueli sp. nov. and P. (C.) bareai sp. nov., these species showing, as well as smaller shells with a lower SL–LBW value (Appendix Table 1), different lateral teeth formula [six lateral cusps in P. (C.) falkneri , three in P. (C.) manueli sp. nov. and four in P. (C.) bareai sp. nov.], fewer gill filaments (12–19), a not so slender penis with a smaller patch of pigmentation and shorter seminal receptacle without duct, approximately half the length of that in P. (C.) luisi .

Because of its restricted distribution area, Pseudamnicola (C.) luisi has been included as “Near threatened, NT” in the Red Book of Invertebrates of Andalusia ( Barea-Azcón et al. 2008).

Figures

Figure 1. Distribution map of the Pseudamnicola species examined.

Figure 2. Shells of Pseudamnicola (C.) luisi. (A, C–F) Shells from La Gitana spring in La Peza, Granada (type locality, MNCN 15.05/49148); B: shell from Polvorista stream, Quéntar, Granada (MNCN 15.05/49155); (D–F) protoconch and detail of protoconch microsculpture.

Figure 3. Operculum and radula of Pseudamnicola (C.) luisi from La Gitana spring in La Peza, Granada (type locality, MNCN 15.05/49148). (A) Internal side of the operculum; (B) external side of the operculum; (C) radula; (D) rows of teeth of the radula; (E) central tooth; (F) detail of an outer marginal tooth.

Figure 4. Anatomy of Pseudamnicola (C.) luisi from the type locality (MNCN 15.05/49148). (A, B) Partial nervous system; (C) ctenidium and osphradium; (D) prostate gland; (E) stomach; (F) head of a male and penis; (G) female genitalia; (H) bursa copulatrix and seminal receptacle. Gc, gastric caecum; PW, pallial wall; Ro, renal oviduct; SR, seminal receptacle.

Figure 26. Bayesian 50% majority rule consensus tree inferred employing cytochrome c oxidase subunit I (COI) mitochondrial gene partial sequence. The numbers above branches represent Bayesian posterior probabilities. Drawings of synapomorphies are referred to: (1) Shell shape, (2) Penis shape, (3) Seminal receptacle and pigmentation on renal oviduct, (4) Bursa copulatrix shape, (5) Lateral teeth of the radula, (6) Length of gastric caecum, (7) Length of supraoesophageal connective. (∗∗) and (∗∗∗) symbolize two and three specimens with identical haplotype respectively. Branch lengths calculated as the mean branch length of all trees in the posterior distribution in which this branch is present. Scale bar: number of estimated changes per site.