Intermaria kermanshahensis ( Glöer & Pešić, 2009 ) Gloer & Pesic, 2009

Diana Delicado, ladimir Pešić & Peter Glöer, 2016, Unraveling a new lineage of Hydrobiidae genera (Caenogastropoda: Truncatelloidea) from the Ponto-Caspian region, European Journal of Taxonomy 208, pp. 1-29 : 12-16

Intermaria kermanshahensis ( Glöer & Pešić, 2009) comb. nov.

Figs 4–5 , Tables 2–3

Pseudamnicola kermanshahensis Glöer & Pešić, 2009: 38 , pl. 6, figs 7–10.

Sarkhia kermanshahensis – Glöer & Pešić, 2012: 33 , fig. 12h comb. nov.

New diagnosis

Shell ovate-conic, yellowish, with pyriform aperture; protoconch microsculpture slightly wrinkled; central radular tooth formula 4–C–4/2–2; pyriform bursa copulatrix; one seminal receptacle elongate with short duct; penis gradually tapering with small distal lobe on inner edge, end tapered; nervous system elongated (mean RPG ratio = 0.50) with slight black pigmentation.

Material examined

Holotype

IRAN: ZMH 51404: 4 mm height, 2.7 mm width.

Paratypes

IRAN: ZMH 51405 (5 ex.) and P. Glöeris (66 ex.) collection.

Type locality

IRAN: spring between Sarab and Sahneh cities , Kermanshah Province, 34º27' N 47º44' E, 27 Jun. 2005.

Description

Shell ovate-conic with 4.25–4.5 whorls, height 3–4 mm ( Fig. 4 A–C, Table 2 ); periostracum yellowish; protoconch approximately 500 µm wide with 1.4 whorls and nucleus around 135 µm long; protoconch microsculpture slightly wrinkled ( Fig. 4 D); body whorl about ⅔ total length; rest of whorls slightly convex with deep sutures; aperture complete, pyriform, inner lip thicker than outer lip; peristome margin straight ( Fig. 4 C).

Operculum with 2 whorls approximately ( Fig. 4 E–F) and muscle attachment area oval and located near the nucleus.

Radula intermediate length (25% total shell length) bearing about 55 rows of teeth; central tooth formula 4–C–4/2–2 ( Fig. 4 G, H); lateral teeth formula 3–C–3; inner marginal teeth having 15–18 sharp cusps; outer marginal teeth having 12–14 sharp cusps ( Fig. 4 I).

Pigmentation and anatomy

Head light brown pigmented from snout to neck; tentacles also brown pigmented except on ocular lobes; snout as long as wide, with medial lobation. Ctenidium extended across most of pallial cavity with 18–21 narrow gill filaments; osphradium three times longer than wide and opposite middle of ctenidium ( Fig. 5 A, Table 3 ).

Nervous system with black pigmentation and elongate (mean RPG ratio 0.50); cerebral ganglia equal in size ( Fig. 5 B, Table 3 ).

Female pallial oviduct with a capsule gland slightly shorter than albumen gland ( Fig. 5 C, Table 3 ); pyriform bursa copulatrix with a duct as long as bursa length, and lying against the middle section of the albumen gland; renal oviduct white from the insertion point of bursal duct to the seminal receptacle and hereafter black making one or two loops; one elongate seminal receptacle with short duct ( Fig. 5 D).

Male genitalia with penis gradually tapering bearing a small distal lobe in the inner edge; slightly grayish pigmented on the distal section in some specimens ( Fig. 5 E, F); prostate gland about two times longer than wide ( Fig. 5 G, Table 3 ).

Remarks

Apart from differences in body dimensions and in certain anatomical features (explained above), the penial distal lobe is more prominent in this species than in I. zagrosensis . Uncorrected genetic distances are, on the contrary, low between these two species (0.2% for COI fragment, Table 4 ), though sister taxa in the subfamily Pyrgulinae are often genetically very close (e.g., COI p-distances of 0.3% between species of the genus Macedopyrgula Radoman, 1973 ). Given this minor genetic variation between congeners, these observed anatomical differences could potentially reflect intraspecific variation.

Ecology and distribution

Known only from a spring in the Kermanshah Province, Iran.

Figures

Fig. 4. Shell, operculum and radula of Intermaria kermanshahensis (Glöer & Pešić, 2009) gen. et comb. nov. from a spring near Sarabe - Sahneh city, Kermanshah Province, Iran. A – B. Shell in front view. C. Shell in lateral view. D. Protoconch and microsculpture. E – F. Internal and external side of the operculum. G. Rows of teeth of the radula. H. Central teeth. I. Detail of outer marginal teeth.

Fig. 5. Anatomy of Intermaria kermanshahensis (Glöer & Pešić, 2009) gen. et comb. nov. from a spring near Sarabe - Sahneh city, Kermanshah Province, Iran. A. Ctenidium and osphradium. B. Partial nervous system. C. Female genitalia. D. Bursa copulatrix and seminal receptacle. E – F. Head of a male and penis. G. Prostate gland. Anatomical abbreviations given in the Material and methods section, except DL (distal lobe).