Laspionchis bourkei bourkei Dayrat & Goulding

Dayrat, Benoit, Goulding, Tricia C., Khalil, Munawar, Comendador, Joseph, Xuan, Qu ảng Ngo, Tan, Siong Kiat & Tan, Shau Hwai, 2019, A new genus of air-breathing marine slugs from South-East Asia (Gastropoda, Pulmonata, Onchidiidae), ZooKeys 877, pp. 31-80 : 59

Laspionchis bourkei bourkei Dayrat & Goulding ssp. nov. Figs 17 A–D , 18 A–D, G, H , 19 A–C , 20 C–F , 21A , 22A , 23E, F , 24 A–D, F

Holotype.

The type locality and the holotype of the nominotypical subspecies L. bourkei bourkei are the same as those of the nominal species L. bourkei (ICZN Arts. 47.1, 61.2, and 72.8).

Additional material examined.

AUSTRALIA - Northern Territory • 1 specimen 8/4 mm [1616]; Darwin, Lee Point Road, Buffalo Creek; 12°20.460'S, 130°54.600'E; 13 Aug. 2012; B Dayrat and party leg.; st 60, narrow Rhizophora mangrove by a river with very dry and hard mud NTM P.57616. • 4 specimens 20/12 mm [1652], 21/13 mm [1656], 23/15 mm [1617], 20/15 mm [1618]; same collection data as for the holotype; NTM P.57617. • 4 specimens 18/10 mm [1621], 19/12 mm [1659], 32/20 mm [1666], 19/12 mm [1673]; Darwin, Talc Head; 12°28.765'S, 130°46.297'E; 15 Aug. 2012; B Dayrat and party leg.; st 62, large and open forest of Sonneratia alba with soft mud; NTM P.57618. • 3 specimens 25/18 mm [1692], 22/15 mm [1693], 22/15 mm [1694]; Darwin, end of the Channel Island Road; 12°33.557'S, 130°52.894'E; 17 Aug. 2012; B Dayrat and party leg.; st 66, sequence of Sonneratia , Rhizophora , and Ceriops ; NTM P.57619.

Distribution

( Fig. 7 ). Australia (Northern Territory).

Habitat

( Fig. 17 A–D ). Same as the entire species Laspionchis bourkei (see above).

Etymology.

See above, the species L. bourkei .

Diagnosis

(Table 3 ). Externally, the three subspecies of L. bourkei cannot be distinguished. Internally, L. bourkei bourkei differs from both L. bourkei lateriensis and L. bourkei matangensis . Indeed, L. bourkei bourkei is characterized by a short retractor muscle of the penis which inserts in the anterior third of the visceral cavity while the retractor muscle is vestigial or absent in L. bourkei lateriensis and L. bourkei matangensis . Also, the spine of the accessory penial gland is on average slightly longer in L. bourkei bourkei than in L. bourkei lateriensis and L. bourkei matangensis .

Color and morphology of live animals

( Fig. 18 A–D, G, H ). Identical to the species L. bourkei (see above).

Digestive system

( Figs 19 A–C , 20 C–F ). Identical to the species L. bourkei (see above). Examples of radular formulae are in Table 4 . Radulae measure up to 2.9 mm in length.

Reproductive system

( Fig. 21A ). Identical to the species L. bourkei (see above).

Copulatory apparatus

( Figs 22A , 23E, F , 24 A–D, F ). Similar to the species L. bourkei (see above) acknowledging some minor variations: the length of the spine of the accessory penial gland ranges from 0.75 mm [1657 H] (NTM P.57615) to 1 mm [1666] (NTM P.57618), the retractor muscle is short (as long as the penial sheath) and inserts in the first third of the visceral cavity, and penial hooks measure from 20 to 35 μm.

Remarks.

See above, the remarks on the species Laspionchis bourkei .

Figures

Figure 7. Geographical distribution of the two species of Laspionchis. Distinct colors are used for each subspecies of L. bourkei. The colors used are the same as those used in the phylogenetic trees (Figs 2 - 5). Colored areas correspond to hypothetical geographical ranges based on known records.

Figure 17. Habitats, Laspionchis bourkei A-D L. bourkei bourkei Australia, Northern Territory E L. bourkei lateriensis, Indonesia, Ambon. A Avicennia on sandy mud (st 61, type locality) B same as A C large Sonneratia alba, open forest, soft mud by shore (st 62) D Sonneratia, Rhizophora, and Ceriops mangrove (st 66) E mudflat beside a mangrove and a creek (st 128, type locality).

Figure 18. Live animals, Laspionchis bourkei A-D, G, H L. bourkei bourkei Australia, Northern Territory E, F, I L. bourkei lateriensis, Indonesia, Ambon. A Dorsal view, 20 mm long [1618] (NTM P. 57617) B dorsal view, 21 mm long [1656] (NTM P. 57617) C holotype, dorsal view, 23 mm long [1657 H] (NTM P. 57615) D dorsal view, 19 mm long [1673] (NTM P. 57618) E dorsal view, 12 mm long [2743] (UMIZ 00116) F dorsal view, 17 mm long [2753] (UMIZ 00116) G ventral view, 19 mm long [1659] (NTM P. 57618) H ventral view, 23 mm long [1617] (NTM P. 57617) I ventral view, same as E.

Figure 19. Digestive system, dorsal view, Laspionchis bourkei A-C L. bourkei bourkei, Australia, Northern Territory D Holotype, L. bourkei lateriensis, Indonesia, Ambon E, F L. bourkei matangensis, Peninsular Malaysia. A [1673] (NTM P. 57618) B [1666] (NTM P. 57618) C [1693] (NTM P. 57619) D [6064 H] (UMIZ 00115) E [5959] (USMMC 00056) F holotype, [5958 H] (USMMC 00055). Scale bars: 2 mm (A, C-E), 2.5 mm (B), 1 mm (F). Abbreviations: ddg dorsal digestive gland i intestine pdg posterior digestive gland r rectum st stomach.

Figure 20. Radula, Laspionchis bourkei A, B L. bourkei matangensis, Peninsular Malaysia [5965] (USMMC 00056) C-F Holotype, L. bourkei bourkei, Australia, Northern Territory [1657 H] (NTM P. 57615). A Rachidian and innermost lateral teeth B lateral teeth C rachidian and lateral teeth D rachidian and innermost lateral teeth E lateral teeth F outermost lateral teeth. Scale bars: 10 μm (A, D, F), 30 μm (B), 100 μm (C), 80 μm (E).

Figure 21. Posterior, hermaphroditic (female) reproductive system, Laspionchis bourkei. A Holotype, L. bourkei bourkei, Australia, Northern Territory, [1657 H] (NTM P. 57615) B holotype, L. bourkei lateriensis, Indonesia, Ambon, [6064 H] (UMIZ 00115) C holotype, L. bourkei matangensis, Peninsular Malaysia, [5958 H] (USMMC 00055). Scale bars: 2 mm (A), 1 mm (B, C). Abbreviations: dd deferent duct fgm female gland mass hg hermaphroditic gland ov oviduct rs receptaculum seminis sp spermatheca.

Figure 22. Anterior, male, copulatory apparatus, Laspionchis bourkei. A Holotype, L. bourkei bourkei, Australia, Northern Territory, [1657 H] (NTM P. 57615) B holotype, L. bourkei lateriensis, Indonesia, Ambon, [6064 H] (UMIZ 00115) C holotype, L. bourkei matangensis, Peninsular Malaysia, [5958 H] (USMMC 00055). Scale bars: 1 mm (A), 2 mm (B), 0.5 mm (C). Abbreviations: ag accessory penial gland dd deferent duct ms muscular sac ps penial sheath rm retractor muscle v vestibule.

Figure 23. Penial hooks, Laspionchis bourkei A-D Holotype, L. bourkei lateriensis, Indonesia, Ambon [6064 H] (UMIZ 00115) E, F L. bourkei bourkei, Australia, Northern Territory [1692] (NTM P. 57619). Scale bars: 40 μm (A, E), 20 μm (B), 5 μm (C, D), 4 μm (F).

Figure 24. Spine of the accessory penial gland, Laspionchis bourkei A-D, F L. bourkei bourkei, Australia, Northern Territory E, G L. bourkei lateriensis, Indonesia, Ambon. A Holotype, [1657 H] (NTM P. 57615) B [1666] (NTM P. 57618) C [1692] (NTM P. 57619) D [1673] (NTM P. 57618) E holotype, [6064 H] (UMIZ 00115) F same as A G same as E. Scale bars: 100 μm (A-E), 10 μm (F, G).