Paraproto murrayae Guerra-García & Keable & Ahyong 2020, n. sp.
Creators: name: Guerra-García, José M.
name: Keable, Stephen J.
name: Ahyong, Shane T.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Caprellidae
Paraproto
Paraproto murrayae

description: Paraproto murrayae n. sp.
(Figs. 1–12)
urn:lsid:zoobank.org:act: 29CC2C6F-4B25-4848-BDE1-44E9BC56084D
Type material. Holotype: AM P.83424, mature male (vial + 2 slides; mouthparts dissected, used for description, figured), north side of Bass Point, north-west of ‘ The Gutter’, New South Wales, Australia, 34°35’28”S, 150°53’58”E, 18.7 m depth, water temperature 19.3°C, RV Baragula, collected on SCUBA, from hairy brown algae on top of rocks, fixed in 7% formalin, preserved 80% ethanol, coll. A. Murray, 1 May 2010. Paratypes (all data same as for the holotype): AM P. 101350, mature female “a” (vial + 1 slide; mouthparts dissected, used for description, figured; photographed alive, Fig. 1); AM P. 101351, mature male “b” (vial, no slides; not dissected; photographed alive, Fig 1); AM P. 101352, mature male “c” (vial + 1 slide; mouthparts dissected); AM P. 101353, 2 males (vial, two specimens, no slides). An additional registration number AM P. 101354 was assigned for a vial containing all the mixed detached pereopods (pereopod 5, 6 and 7) that could not be associated with specific individuals. Many pereopods were found at the bottom of the vials so it was not possible to assign them to a particular specimen.
Additional material examined. North of Ulladulla, east of Bendalong and Red Point, New South Wales, Australia, 34°15’00”S, 150°32’46”E, 16 m depth, water temperature 20°C, RV Baragula, collected by SCUBA, from hairy brown algae (cf. Ectocarpus sp.), fixed in 10% formalin, preserved in 80% ethanol, coll. A.D. Hegedus, 11 May 2013: AM P.101355, 65 specimens (12 mature males, 6 mature females, 4 premature females, 43 juveniles); AM P. 101356, 8 specimens (2 juveniles, 1 male juvenile, 1 premature female, 2 mature males, 2 mature females were used for figures of ontogenetic development).
South of Broulee Island, New South Wales, Australia, 35° 50’ 49” S, 150° 11’ 5” E, 8m depth, water temperature 16°C, RV Connemara, hand collected by SCUBA, from macroalga Halopteris platycena Sauvageau, 1904, 25 October 2002, coll. A.J. Millar & N. Yee, NSW 1990: AM P.103289, 62 specimens (12 males, 18 females, 9 premature females, 23 juveniles).
Etymology. The species is dedicated to Anna Murray, who collected the type material of the species and was indispensable in organizing the fieldwork during which all the material was collected; JMGG is very grateful to Anna for her hospitability, kindness and support during his stays at the Australian Museum.
Description. Holotype, male (6.2 mm) AM P.83424. Body (Fig. 2). Dorsally smooth. Head rounded, fused with pereonite 1, lacking any projections, length 1.1 mm, eyes present. Length of pereonites 2–7, 1.0 mm, 0.8 mm, 0.9 mm, 1.1 mm, 0.9 mm, 0.4 mm respectively.
Gills (Fig. 2). Present on pereonites 3–4, elongated, length about three times width.
Mouthparts (Figs. 3–4). Upper lip symmetrically bilobed, smooth. Lower lip without setae; inner lobes separate. Mandibles with 3-articulate palp; setal formula for distal article 1-3-1; mandibular molar absent; left mandible with incisor and lacinia mobilis 5-dentate, followed by 2 trapezoid plates and row of setae; incisor of right mandible 6- dentate, lacinia mobilis plate-like, followed by additional plate and row of setae; molar flake absent. Maxilla 1 outer lobe with 5 robust spines; palp 2-articulate, distal article with 4 apical spines and 6 setae medially. Maxilla 2 inner and outer lobe with ca. 8 setae respectively. Maxilliped inner plate rectangular, carrying 3 strong spines and 2 setae; outer plate oval, with row of setae and small tubercles on inner margin; palp 4-articulate, inner margin setose.
Antennae (Figs. 2, 5). Antenna 1 about 2/3 body length; proximal article of peduncle without projection; flagellum with 15 articles. Antenna 2 about half of antenna 1 length; flagellum 5-articulate.
Gnathopods (Figs. 2, 5, 6). Gnathopod 1 basis longer than the combination of ischium, merus and carpus; propodus triangular, length about 1.5 width, palm with 5 proximal grasping spines; dactylus falcate, inner margin lined with very fine setules. Gnathopod 2 inserted on the posterior half of pereonite 2; basis almost twice pereonite 2 length; ischium short; merus rounded; carpus slender, about twice ischium length; propodus elongated, as long as basis, with grasping spine medially, small U-notch and several grasping spines distally; dactylus short, curved, thickened medially.
Pereopods (Figs. 7–8) Pereopods 3 and 4 subequal, 6-articulate, coxae large (Fig. 9); carpus with 3 grasping spines; propodus with 2 proximal grasping spines, row of setae ventrally and thick bunch of setae dorsodistally. Pereopod 5 6-articulate; carpus with grasping spine; propodus without grasping spine, with thick bunch of setae dorsodistally; dactylus short, curved. Pereopods 6 and 7 subequal, 6-articulate; merus with grasping spine; carpus with 3 grasping spines; propodus with 2 pairs of grasping spines proximally and smaller spine distally; dactylus with setules.
Penes (Fig. 10) situated laterally, short, triangular.
Abdomen (Fig. 10) with pleopods reduced to a small plate; 2 pairs of 2-articulate appendages, peduncle elongate, ramus short, about ¼ of peduncle length; telson small, with pair of plumose setae.
Paratype “a”, female (4.7 mm) AM P. 101350. Head and pereonite 1 completely fused (Fig. 2), 0.6 mm, suture absent. Length of pereonites 2–7, 0.7 mm, 0.7 mm, 0.8 mm, 0.8 mm, 0.8 mm, 0.4 mm respectively. Pereonite 2 with tiny lateral acute projection proximally. Antenna 1 flagellum 11-articulate. Antenna 2 flagellum 4-articulate Oostegites on pereonites 3 and 4, first pair setose (Fig. 1, 2). Gnathopod 2 (Figs. 2, 6) inserted on anterior half of pereonite 2; basis as long as pereonite 2; propodus palm formed by medial projection with 3 robust grasping spines and row of smaller spines to distal end. Abdomen similar to that of holotype male (Fig. 10).
Intraspecific variation and ontogenetic development
Most of the morphological characters of Paraproto murrayae n. sp. are relatively constant in all the specimens examined. All mature males and females have a similar pattern, lacking dorsal projections on all pereonites. A small anterolateral projection is present on pereonite 2 of females, but vestigial or absent in males (as in the holotype; Fig. 2). The morphology of the antennae, gnathopods and pereopods is similar in all mature specimens examined. For the mouthparts, the inner plate of the maxilliped always has 3 strong spines, and apart from the holotype, the tiny tubercles on the inner margin of outer plate are less apparent in the three specimens dissected. The maxilla 1 outer lobe has 5 or 6 robust spines. The maxilla 2 is similar in all the dissected specimens, but the number of setae of inner and outer lobe ranges from 7 to 9. The number of proximal grasping spines of gnathopod 1 varies, being 4 or 5.
In small juveniles the flagellum of antennae 2 is 2-articulate. The number of articles of the antennae 1 flagellum increases with increasing body size (being 3 in the smallest juvenile examined and 15 in larger specimens, such as the holotype male) (Fig. 11). The aspect of male gnathopod 2 changes considerably during development (Fig. 12). Initially, the gnathopod 2 propodus is wider, provided with several grasping spines proximally, and dactylus length is approximately half that of the propodus. As size increases, the number and location of these grasping spines decreases to one in adult specimens and it moves to a medial instead of proximal position. The basis and carpus of gnathopod 2 also becomes more elongate with increasing body size (Fig. 12).
description: Published as part of Guerra-García, José M., Keable, Stephen J. & Ahyong, Shane T., 2020, A new species of Paraproto (Crustacea: Amphipoda) from southern New SouthWales, Australia, pp. 271-293 in Zootaxa 4755 (2) on pages 272-274, DOI: 10.11646/zootaxa.4755.2.4, http://zenodo.org/record/3731607