Paradiastylis botanybayensis, Gerken, 2014

Gerken, Sarah, 2014, Eleven New Species and a New Genus of Diastylidae (Crustacea: Cumacea) from Australia and One New Species from Canada, Records of the Australian Museum 66 (1), pp. 1-62 : 53-59

publication ID	https://doi.org/ 10.3853/j.2201-4349.66.2014.1601
persistent identifier	https://treatment.plazi.org/id/03FB87F1-2450-2530-FC42-FDE5FE42FDC1
treatment provided by	Carolina
scientific name	Paradiastylis botanybayensis
status	sp. nov.

Treatment

Paradiastylis botanybayensis View in CoL n. sp.

Figs 34–37 View Figure 34 View Figure 35 View Figure 36 View Figure 37

Type material. Holotype ovigerous female, AM P53685, 34°00'S 151°12'E, 13 m, State Pollution Control Commission, 10 Mar. 1977 GoogleMaps . Paratype subadult female, dissected, AM P53681, 33°59'22"S 151°12'45"E, 19.2 m, State Pollution Control Commission, 4 Feb. 1977 GoogleMaps . Paratype adult male, dissected, AM P53671, 33°58'44"S 151°12'30"E, 7.5 m, State Pollution Control Commission, 13 Dec. 1976 GoogleMaps . Paratype 1 female, AM P85785, 33°58'39"S 151°12'22"E, 7.5, State Pollution Control Commission, 8 Dec. 1976 GoogleMaps . Paratypes 2 specimens, P42011, 33°58'45"S 151°11'02"E, 7 m, Australian Museum, 28 July 1992 GoogleMaps .

Other material examined. None.

Diagnosis. Female and subadult male. Carapace covered in small spines, without ridges. Telson longer than pleonite 6, but less than 1.5 × pleonite 6, terminal setae tiny. Uropod endopod article 1 longer than articles 2 and 3 together. Adult male. Carapace without spines, without ridges. Antennule with brush of setae on peduncle article 3. Antennae extending to posterior border of telson. Telson longer than pleonite 6, terminal setae long.

Description

Ovigerous female. Holotype ovigerous female, AM P53685, 3.2 mm; paratype ovigerous female, AM P53681, 3.5 mm. —Carapace covered in small spines, may be difficult to see in poorly preserved or poorly calcified specimens; pseudorostral lobes 0.5 × carapace length, acute; eye lobe 0.07 × carapace length, broader than long, with lenses; carapace 3.0 × length of pereonites together ( Figs 34A–B View Figure 34 ). — Paratype ovigerous female, AM P53681, 3.5 mm. —Antennule peduncle article 1 0.5 × length of articles 2 and 3 together, with 1 simple and 1 pappose setae, margin thickly lined with fine hair-like setae; article 2 0.8 × article 1 length, with 4 simple and 2 pappose setae; article 3 1.9 × article 2 length, slender, with 1 simple and 2 pedunculate setae; main flagellum of 3 articles, with 2 aesthetascs and simple seta; accessory flagellum of 1 article, 0.4 × main flagellum length, shorter than main flagellum article 1, with 4 simple setae ( Fig. 34C View Figure 34 ). —Antenna of 4 articles, each with 1 plumose or pappose seta ( Fig. 34D View Figure 34 ). —Mandible navicular, with 13 microserrate setae medially ( Fig. 34E View Figure 34 ). —Maxillule with 2 endites; outer endite with row of stout simple setae, medial margin lined with fine hair-like setae; inner endite with 3 simple and 1 tricuspid setae, medial margin with fine hair-like setae; palp with 2 microserrate setae ( Fig. 34F View Figure 34 ). —Maxilla with 3 endites; broad endite distal margin with pappose seta at corner, row of simple and pappose setae, medial margin with row of pedunculate setae and 2 pappose setae; medial narrow endite with 3 microserrate setae terminally; distal narrow endite with 4 microserrate setae terminally; both narrow endites extending barely past distal margin ( Fig. 34G View Figure 34 ). —Maxilliped 1 basis produced as lobe with 4 simple, 8 pappose, 2 hook and 1 stout bicuspid setae; ischium present, unarmed; merus unarmed; carpus 1.7 × merus length, with 3 pappose, many simple and 5 beak setae on medial face, plumose seta laterally; propodus 0.6 × carpus length, with 1 simple, 3 plumose and 1 pappose setae; dactylus 0.9 × propodus length, with 3 simple setae ( Fig. 34H View Figure 34 ). —Maxilliped 2 basis 0.6 × length of all other articles together, with 3 plumose and 2 pappose setae distally; ischium 0.04 × basis length, unarmed; merus 8.0 ischium length, with pappose seta medially, plumose seta laterally; carpus 2.0 × merus length, with 7 pappose setae medially, plumose seta laterally; propodus 0.7 × carpus length, with 5 pappose and 1 plumose setae; dactylus 0.5 × propodus length, with 3 simple setae ( Fig. 34I View Figure 34 ). —Maxilliped 3 basis 1.2 × length of all other articles together, broad, with 10 pappose setae medially, distal corner expanded, with 5 plumose setae; ischium 0.1 × basis length, with pappose seta; merus 1.0 × ischium length, with pappose seta medially, plumose seta laterally; carpus 2.0 × merus length, with 4 pappose setae medially, plumose seta laterally; propodus 1.1 × carpus length, with 2 plumose setae medially, plumose seta laterally; dactylus 0.6 × propodus length, with 5 simple setae terminally ( Fig. 35A View Figure 35 ). —Pereopod 1 basis 0.6 × length of all other articles together, with 2 simple and 17 plumose setae; ischium 0.03 × basis length, unarmed; merus 5.0 × ischium length, with simple seta; carpus 3.0 × merus length, with 5 simple setae; propodus 1.3 × carpus length, with 13 simple setae; dactylus 0.4 × propodus length, with 12 simple setae and simple seta terminally; exopod 0.7 × basis length, basal article with simple seta, flagellum with plumo-annulate setae ( Fig. 35B View Figure 35 ). —Pereopod 2 basis 0.8 × length of all other articles together, with 3 plumose setae; ischium 0.06 × basis length, unarmed; merus 3.5 × ischium length, with 3 simple setae; carpus 2.1 × merus length, with 7 simple setae; propodus 0.4 × carpus length, with plumose seta; dactylus 1.8 × propodus length, with 6 simple setae and 2 simple setae terminally; exopod 1.2 × basis length, basal article with 4 simple setae, flagellum with plumo-annulate setae ( Fig. 35C View Figure 35 ). —Pereopod 3 basis with 8 simple and 1 pedunculate setae; ischium with 2 simple setae; merus 4.0 × ischium length, with 4 simple setae; carpus 0.8 × merus length, with 4 simple and 4 annulate setae; propodus 0.5 × carpus length, with 1 annulate and 1 pedunculate setae; dactylus 0.6 × propodus length, with 1 simple and simple seta terminally ( Fig. 35D View Figure 35 ). —Pereopod 4 basis 0.7 × length of all other articles together, with 9 simple and 3 pedunculate setae; ischium 0.2 × basis length, with 3 simple setae; merus 2.2 × ischium length, with 3 simple setae; carpus 0.9 × merus length, with 1 simple and 7 annulate setae; propodus 0.6 × carpus length, with annulate seta; dactylus 0.5 × propodus length, with 2 simple setae and simple seta terminally ( Fig. 35E View Figure 35 ). —Pereopod 5 basis 0.6 × length of all other articles together, with 7 simple setae; ischium 0.2 × basis length, with 2 simple setae; merus 3.3 × ischium length, with simple seta; carpus 1.0 × merus length, with 2 simple and 2 annulate setae; propodus 0.5 × carpus length, with annulate seta; dactylus 0.6 × propodus length, with simple seta and simple seta terminally ( Fig. 35F View Figure 35 ). —Telson 1.4 × length of pleonite 6, without stout lateral setae, 2 small simple terminal setae ( Figs 35G–H View Figure 35 ). —Uropod peduncles 2.4 × pleonite 6 length, 1.7 × telson length, with 15–16 simple setae with single subterminal setule medially, 0–1 simple setae laterally. Uropod endopod of 3 articles, 0.5 × peduncle length; article 1 1.3 × articles 2 and 3 together, with 3 simple setae with single subterminal setule medially; article 2 0.4 × article 1 length, with 2 simple setae with single subterminal setule medially; article 3 0.8 × article 2 length, with simple seta with single subterminal setule medially, terminal seta simple. Uropod exopod of 2 articles, 0.9 × length of endopod; article 1 0.2 × article 2 length, with 0–1 simple setae; article 2 with 5 simple setae laterally, terminal seta simple, longer than endopod terminal seta ( Fig. 35G View Figure 35 ).

Adult male. Paratype adult male, AM P53671, 2.8 mm. — Carapace unornamented; pseudorostral lobes 0.4 × carapace length, acute; eye lobe 0.1 × carapace length, with lenses; carapace 3.9 × length of pereonites together ( Fig. 36A View Figure 36 ). — Antennule peduncle article 1 0.7 × length of articles 2 and 3 together, with 1 simple and 1 plumose setae, margin thickly lined with fine hair-like setae; article 2 0.6 × article 1 length, with 6 simple setae; article 3 1.5 × article 2 length, with cluster of simple setae, 1 pedunculate seta; main flagellum of 4 articles, with 2 aesthetascs and 3 simple setae; accessory flagellum of 3 articles, 0.6 × main flagellum length, with 2 simple setae ( Fig. 36B View Figure 36 ). —Antenna extending to posterior border of telson; peduncle of 5 articles, articles 1,2, and 4 each with plumose seta; article 5 with ranks of short setae, incompletely circling article; flagellum with long articles, each with several simple setae ( Figs 36A, C View Figure 36 ). —Maxilliped 3 basis 1.5 × length of all other articles together, broad, with 3 simple and 12 pappose setae medially, expanded distally with 5 plumose setae, lateral margin lined with fine hair-like setae; ischium 0.07 × basis length, with pappose seta; merus 1.2 × ischium length, with pappose seta medially, plumose seta laterally; carpus 2.3 × merus length, with plumose seta medially, plumose seta laterally; propodus 0.9 × carpus length, with 5 plumose setae medially, plumose seta laterally; dactylus 0.8 × propodus length, with 5 simple setae terminally; exopod 0.7 × basis length, basal article with 2 plumose setae, flagellum with plumo-annulate setae ( Fig. 36D View Figure 36 ). —Pereopod 1 basis 0.6 × length of all other articles together, with 21 plumose setae; ischium 0.09 × basis length, with plumose seta; merus 1.8 × ischium length, unarmed; carpus 3.4 × merus length, with 2 simple setae; propodus 1.2 × carpus length, with 12 simple setae; dactylus 0.4 × propodus length, with 9 simple setae, simple seta terminally; exopod 0.6 × basis length, basal article with 2 plumose setae, flagellum with plumo-annulate setae ( Fig. 37A View Figure 37 ). — Pereopod 2 basis 0.8 × length of all other articles together, with 2 simple and 7 plumose setae, expanded distally to mid-merus; ischium 0.2 × basis length, unarmed; merus 1.1 × ischium length, with 2 plumose setae; carpus 2.3 × merus length, with 7 simple setae; propodus 0.3 × carpus length, with simple seta; dactylus 1.5 × propodus length, with 4 simple setae and 2 simple setae terminally; exopod 1.1 × basis length, basal article unarmed, flagellum with plumoannulate setae ( Fig. 37B View Figure 37 ). —Pereopod 3 basis 1.1 × length of all other articles together, with 4 plumose setae; ischium 0.1 × basis length, with 3 simple setae; merus 3.0 × ischium length, with 4 simple setae; carpus 0.8 × merus length, with 7 annulate setae; propodus 0.5 × carpus length, with annulate seta; dactylus 0.6 × propodus length, with 3 simple setae, simple seta terminally; exopod 1.1 × basis length, basal article with 2 simple and 1 plumose setae, flagellum with plumo-annulate setae ( Fig. 37C View Figure 37 ). —Pereopod 4 basis 0.9 × length of all other articles together, with 3 plumose setae; ischium 0.1 × basis length, with annulate seta; merus 3.5 × ischium length, with 3 simple and 1 annulate setae; carpus 0.6 × merus length, with 6 annulate setae; propodus 0.6 × carpus length, with annulate seta; dactylus 0.6 × propodus length, with 2 simple setae, simple seta terminally; exopod 1.2 × basis length, basal article with plumose seta, flagellum with plumo-annulate setae ( Fig. 37D View Figure 37 ). —Pereopod 5 basis 0.8 × length of all other articles together, with 1 simple and 4 plumose setae; ischium 0.1 × basis length, with simple seta; merus 3.3 × ischium length, with 1 simple and 1 plumose setae; carpus 1.0 × merus length, with 1 simple and 4 annulate setae; propodus 0.4 × carpus length, with annulate seta; dactylus 0.8 × propodus length, with simple seta and simple seta terminally ( Fig. 37E View Figure 37 ). —Telson 1.1 × length of pleonite 6, without stout lateral setae, with few slender simple setae, 2 long simple terminal setae ( Fig. 37F View Figure 37 ). —Uropod peduncles 2.5 × pleonite 6 length, 2.2 × telson length, with 1 simple and 18 simple setae with single subterminal setule medially, 1–2 simple setae laterally. Uropod endopod of 3 articles, 0.6 × peduncle length; article 1 1.4 × length of articles 2 and 3 together, with 6–7 simple setae with single subterminal setule medially, simple seta laterally; article 2 0.4 × article 1 length, with 3–4 simple setae with single subterminal setule medially, simple seta laterally; article 3 0.8 × article 2 length, with 2–3 simple setae with single subterminal setule medially, simple seta laterally, terminal seta simple. Uropod exopod 0.9 × length of endopod; article 1 0.2 × article 2 length; article 2 with 9–10 simple setae, terminal seta simple, longer than endopod terminal seta ( Fig. 37F View Figure 37 ).

Etymology. The species is named botanybayensis for the place the specimens were collected, Botany Bay, Australia.

Remarks. The new species Paradiastylis botanybayensis is most similar to the new species P. berentsae . These two species can be differentiated by the carapace ornamentation and telson. In P. botanybayensis the carapace is covered in small spines in the female, and in P. berentsae the carapace has at most a few scattered spines. It may be difficult to see the carapace spines in P. botanybayensis if the specimen is soft or poorly calcified, in this situation staining with chlorazole black may be useful. In P. berentsae the telson is distinctly shorter than pleonite 6, while in P. botanybayensis the telson is distinctly longer than pleonite 6. The male of P. berentsae is currently unknown, so it is impossible to distinguish between the males of both species.

Other than the carapace ornamentation and telson length, the females of both species are very similar in size, appendages and overall appearance. Hale (1945) points out in his discussion of Dimorphostylis that it appears that the relative length of the post-anal portion of the telson is not particularly useful in diastylid species discrimination in Australian waters; however, the difference in this case is the entire telson length, which has not been suggested to be problematic for species discrimination. The difference in this case is consistent in all specimens encountered of both species, with no specimens that were difficult to ascribe to one species or the other on the basis of telson size.

The other species from Australian waters that might be confused with P. botanybayensis is P. whitleyi , as the uropod endopod proportions are similar in that article 1 is distinctly longer than articles 2 and 3 together. However, P. whitleyi has a distinct post-anal portion to the telson, and stout lateral setae on the telson in the adult male, while the adult male of P. botanybayensis has no post-anal portion on the telson, and no stout lateral setae.