Austrochloritis niangala Shea & Griffiths, 2010

Shea, Michael & Köhler, Frank, 2020, Eastern Australian Land Snail Species Closely Related to Austrochloritis porteri (Cox, 1868), with Description of a New Species (Mollusca, Eupulmonata, Camaenidae), Records of the Australian Museum 72 (3), pp. 63-76 : 70-74

Austrochloritis niangala Shea & Griffiths, 2010

Austrochloritis niangala Shea & Griffiths, 2010 in Stanisic, Shea, Potter & Griffiths, 2010: 384–385 , 536 (holotype AM C.339934 from ESE of Tamworth , NE New South Wales, -31.177° 151.295°).

Austrochloritis kaputarensis Stanisic, 2010 in Stanisic, Shea, Potter & Griffiths, 2010: 384–385 , 536 (holotype QM MO32626 from Dawson Spring, Mt Kaputar, -30.267° 150.167°); new synonym.

Type material examined. Holotype of Austrochloritis niangala, AM C. 339934 (1d, ESE of Tamworth , -31.177° 151.295°) ( Fig. 2C ) , Paratypes, AM C.339935 (1 d, same as holotype), AM C.339933 (3 d, SE of Tamworth, near Three Corner Swamp , 300 m E of “ Carnegie ” HS) . Paratypes of Austrochloritis kaputarensis, AM C. 450448 (8 d, NE of Manilla , Warrabah NP, -30.267° 150.167°), AM C.452038 (1 d, same as AM C.450448).

Non-type material examined. AM C.339566 (1 w, ESE of Tamworth , 3.4 km E of Niangala, -31.30° 151.44°) , AM C.339936 (1 d, 40 km S of Walcha , -31.34° 151.51°) , AM C.446747 (1 d, Oakey Creek Nature Reserve , -31.10° 150.62°), AM C.339817 (1 w, 32 km SE of Kootingal, -31.21° 151.17°) , AM C.108379 (1 w, 3.4 km E of Niangala , -31.30° 151.44°) , AM C.339816 (2 w, same as holotype) , AM C.478245 (7 d, same as holotype), AM C.339928 (2 w, S of Walcha , Ingleba Ck, N of Branga Plains HS, -31.25° 151.54°) , AM C.575258 (3 d, Niangala-Weabonga road, -31.30° 151.37°), AM C.575450 (3 w, 1d, Niangala– Weabonga road, -31.30° 151.37°), AM C.557123 (2 d, 30 km N of Armidale, Thunderbolts Cave, -30.33° 151.67°) , AM C.557124 (2 d, same as AM C.557123), AM C.519090 (1 d, Mt Kaputar NP, Coryah Gap, -30.28° 150.13°) , AM C.480187 (3 w, same as AM C.519090), AM C.519095 (1 d, Mt Kaputar NP, West Kaputar Rock lookout, -30.28° 150.15°), AM C.519099 (10 d, Mt Kaputar NP, Barraba Track, -30.29° 150.18°) , AM C.480188 (4 w, same as AM C.519099), AM C.478644 (4 d, Mt Kaputar NP, Barraba Track, -30.31° 150.21°) , AM C.478832 (4 d, same as AM C.478644), AM C.478653 (5 d, Mt Kaputar NP, South East Fire trail, -30.32° 150.23°), AM C.478658 (8 d, Mt Kaputar NP, eastern park entrance, -30.32° 150.23°), AM C.478674 (3 d, Mt Kaputar NP, below Dawson’s Spring, -30.28° 150.16°), AM C.477015 (1 w, Mt Kaputar NP, Dawson’s Spring, -30.28° 150.16°), AM C.480193 (1 w, Mt Kaputar NP, 4.4 km up from Green Camp, -30.28° 150.12°) , AM C.164945 (4 w, NW of Armidale, W of Guyra , Georges Mountain, -30.23° 151.25°) , AM C.339673 (1 d, same as AM C.164945), AM C.339674 (1 d, same as AM C.164945), AM C.375155 (1 w, 1 d, 21.4 km W of Armidale on Bundarra Rd , -30.49° 151.48°) , AM C. 210134 (4 d, N of Armidale , Tilbuster Ponds, -30.36° 151.68°) , AM C.561050 (3 w, 10 d, Georges Mountain , Basin NR, -30.23° 151.25°) .

Nomenclatural and taxonomic remarks

Both species, A. niangala and A. kaputarensis , were described in the same publication based on shell characters only. Their original descriptions are indicative of their rather close similarity. The purported differences are mainly in the length and density of periostracal setae. However, the reproductive anatomy was previously not documented. We are unable to identify any consistent morphological or anatomical difference between these two taxa. Shells are virtually identical in shape and size and no significant and consistent difference in the density and length of periostracal was observed. 16S sequences assigned to both taxa, respectively, differed from each other by on average 4.3 % p-distance, which may well be in the range of intraspecific genetic variation given the comparatively large geographic distances between the sequenced populations ( Fig. 5 ). Based on the lack of consistent morpho-anatomical differentiation in concert with the rather low amount of mitochondrial differentiation, we consider both taxa as synonyms. Preference is here given to the name A. niangala by First Reviewers Choice. The candidate species Austrochloritis sp. NE3, which has been identified during curatorial work in the collections of theAM, is also considered as conspecific with A. niangala for exhibiting a consistent morpho-anatomy and also because it falls within the sub-clade formed by sequences of A. niangala ( Fig. 1 ).

sp. nov. by ordination of shell height against width.

Description

Shell ( Figs 2 C–F, 3C–F, 6A,B). Medium sized (W= 11.1–15.0 mm, H = 6.2–8.8 mm, N = 3.2–3.9; for n = 20; Table 1), turbinate to depressedly globose, with rounded to slightly shouldered whorls that regularly increase in diameter, sutures rather deeply incised; protoconch sculpture of rugose radials with coarse pustules at apex and with periostracal setae extending well on protoconch; teleoconch sculpture of low growth lines and corrugations with periostracal sculpture of rather straight, moderately widely spaced and occasionally long setae, interstitial microsculpture of very fine wavy periostracal ridgelets and scales; end of last whorl descending strongly below whorl plane on reaching sexual maturity; aperture moderately tilted forward from axis of coiling, without thickened or reflected outer lip and without sulcus behind lip; umbilicus moderately open with U-shaped profile; shell colour pale yellowish brown.

Reproductive anatomy ( Fig. 7 ). Penis cylindrical, narrowing toward genital opening, no penial sheath, penial sculpture of corrugated interlocking longitudinal filaments, distally giving rise to longitudinal rows of strap-like filaments, epiphallus twice as long as penis, with well-developed finger—like epiphallic flagellum at distal end, penial verge broadly conical, with wide longitudinal groove, length equivalent to between about half and one third of length of penis, free; penial retractor attached to proximal third of epiphallus, vas deferens entering head of epiphallus through single pore just below base of epiphallic flagellum; vas deferens narrow to broad at its junction with apex of epiphallus, later tapering to a narrow tubule; vagina cylindrical, as long as penis, inner wall with prominent longitudinal anastomising pilasters and filaments; bursa copulatrix long and broad, particularly at its base, folded or kinked several times and about as long as oviduct, with inflated bulb-like head, aligning with base of albumen gland; hermaphroditic duct inserting into head of talon.

Comparative remarks

Austrochloritis niangala can be distinguished from A. nundinalis by its smaller shell ( Fig. 8 ) and by having straight instead of curved periostracal setae. Both species exhibit a very similar reproductive anatomy, but differ somewhat in the relative length of the bursa copulatrix (longer in A. nundinalis ) and the penial verge (occasionally partly attached to penial wall in A. nundinalis , free in A. niangala ). Like A. nundinalis , the lack of a reflected outer lip and sulcus and the setae extending well onto the protoconch are shell features that distinguish A. niangala from most other congeners. Despite occurring in relative close proximity near Nundle, both species are separated by genetic p-distances of on average 7% (minimum 5.9 %).

Material from the Mt Kaputar NP previously described as Australochloritis kaputarensis does not consistently or significantly differ in shell or reproductive characters from material from near the type locality of A. niangala and is therefore considered as conspecific.

Distribution and ecology

Austrochloritis niangala lives in dry to moist sclerophyll forests on the New England Plateau from Mt Kaputar in the west to near Guyra in east and E of Tamworth in the south ( Fig. 5 ). Most of its range is heavily fragmented into very small remnant patches of forests as large parts of the species’ natural range has been cleared for agriculture.

Figures

Figure 1. Bootstrap consensus tree for 10,000 ultrafast Maximum Likelihood bootstraps as based on Maximum Likelihood Analysis of the concatenated 16S and COI sequence dataset. Sequences of Austrochloritis abrotonus Shea & Griffiths, 2010 were used to root the tree.

Figure 2. Shells (front, top, and umbilical view).(A, B) Austrochloritis nundinalis: A, probable syntype AM C.112312 (Nundle, NSW); B, AM C.575260 (Sheba Dams, E of Nundle); (C–F) Austrochloritis niangala: C, holotype,AM C.339934 (ESE of Tamworth); D, paratype of A. kaputarensis, AM C.452038 (NE of Manilla); E, AM C.478658 (Mt Kaputar); F, AM C.561050 (Georges Mountain, Basin NR); G, Austrochloritis copelandensis sp. nov., holotype AM C.582897 (Copeland Tops). Scale bar = 10 mm.

Figure 5. Occurrence records of Austrochloritis nundinalis, A niangala (= A. niangala, A. kaputarensis, Austrochloritis sp. NE3), and A. copelandensis sp. nov. (= Austrochloritis sp. SN39) from the malacological collection of the Australian Museum. Source of base map: Google Maps.

Figure 7. Reproductive anatomy of Austrochloritis niangala. (A–C) Penial anatomy: A, AM C.575450, A. niangala, Niangala; B, AM C.480188, A. kaputarensis, Mt Kaputar; C, AM C.375155, Austrochloritis sp. NE3, Bundarra; scale bar = 2 mm. (D–F) Reproductive system: D, AM C.575450, A. niangala, Niangala; E, AM C.480188, A. kaputarensis, Mt Kaputar; F, AM C.375155, Austrochloritis sp. NE3, Bundarra; scale bar = 5 mm.

Figure 8. Comparisonof shell dimensionsof Austrochloritis nundinalis, A.niangala, A.kaputarensis, andA.copelandensis