Barryichthys algicola, Conway, Kevin W., Moore, Glenn I. & Summers, Adam P., 2019

Conway, Kevin W., Moore, Glenn I. & Summers, Adam P., 2019, A new genus and two new species of miniature clingfishes from temperate southern Australia (Teleostei, Gobiesocidae), ZooKeys 864, pp. 35-65 : 35

Barryichthys algicola sp. nov. Figures 2B, 3D, E, 4B, 5B, 6B Common name: Green rat clingfish

Genus B sp., Hutchins 1994a: 310

Holotype.

WAM P.27127-016 , female, 16.8 mm SL; Victoria, Jubilee Point , Sorrento (38°20'00"S, 144°45'00"E), 3 March 1981, J.B. Hutchins, CT scan https://doi.org/10.17602/M2/M78489.

Paratypes.

New South Wales: AMS I.137167-002 , 1, 14.2 mm SL; Cape Banks , Botany Bay (34°00'00.0"S, 151°15'00.0"E), 01 March 1992-06 July 1993, N Gallahar. Victoria: WAM P.27127-001, 2 , 16.0-21.0 mm SL; Same as holotype. Tasmania: AMS I.17555-002, 3 , 15.5-15.7 mm SL; The Gardens, north of Binalong Bay (41°14'21.3"S, 148°17'35.8"E), D. Hoese & W. Ivanstoff. - AMS I.17576-012 , 1, 19.0 mm SL; The Gardens, north of Binalong Bay (41°14'21.3"S, 148°17'35.8"E), D. Hoese & W. Ivanstoff. - AMS I.46787-001, 1, 15.6 mm SL; Coles Bay (42°07'28.0"S, 148°16'54.0"E), H. Lloyd. - WAM P.27572-004, 2 , 10.0-13.0 mm SL; West Point, Marrawah (40°55'00"S, 144°42'00"E), 13 March 1982, J.B. Hutchins. - WAM P.27576-003, 1 , 14.0 mm SL; north side of Granville Harbour (41°49'00"S, 145°01'00"E), 18 March 1982, J.B. Hutchins. - WAM P.27559-007, 10 (2C&S), 9.0-12.0 mm SL; St. Helens Point (41°16'00"S, 148°22'00"E), 25 February 1982, J.B. Hutchins.

Diagnosis.

Barryichthys algicola is distinguished from B. hutchinsi by a longer, narrower body (body depth at dorsal-fin origin 7-8% SL vs. 10-11% SL), a more slender head (head width at widest point 55-61% HL vs. 66-75%; depth at orbit 27-29% HL vs. 30-32%; interorbital width 20-24% vs. 27-33% HL), the entire ventral margin of the orbit visible in ventral view (vs. ventral margin of orbit obscured by cheek in ventral view), by having a longer abdominal region with more vertebrae (abdominal vertebrae 21 vs. 17) and more ribs (15 vs. 11-12), a higher number of epicentrals (18-19 vs. 14-15), and a higher total number of vertebrae (42-44 vs. 38-39), and by features of live colour pattern, including body background colour green (vs. golden-yellow to olive-brown) without darker markings along dorsal midline or body side (vs. dorsal midline and lateral body side with darker markings).

Description.

General body shape as in Figs 2B, 3 D–E. Select morphometric and meristic characters are listed in Tables 1, 2. As described for B. hutchinsi except for the following differences. Largest specimen examined 21.0 mm SL. Head narrow; widest point of head only slightly wider than widest part of body. Entire ventral margin of orbit visible in ventral view (Fig. 5B). Dorsal-fin rays 5 or 6. Anal-fin rays 6. Pectoral-fin rays 17. First dorsal-fin pterygiophore inserted between neural spines of vertebrae 23/24. First anal-fin pterygiophore inserted between hemal spines of vertebrae 20/21 or 22/23. Total number of vertebrae 42, 43(*) or 44, consisting of 21 abdominal vertebrae and 21, 22(*) or 23 caudal vertebrae (Fig. 4B). Ribs 15, associated with vertebrae 3-17. Epicentrals 18 or 19, associated with vertebrae 3-20/21.

Sexual Dimorphism.

As described for B. hutchinsi .

Eggs.

A female of 17.2 mm SL from WAM P.27127-001 contained multiple mature eggs (number not counted) in the right ovary. A single excised egg (ca. 0.6 mm in diameter) exhibited a dark orange cap that may represent an "attachment apparatus" at the animal pole as described from the eggs of three species of European gobiesocid by Breining and Britz (2000).

Colouration.

In alcohol, head and body background colour pale cream (Fig. 2B). In life, head and body uniformly green (Fig. 3D, E). A lighter green stripe on side of head, extending from tip of snout to upper part of gill opening, passing through eye. Iris orange. Pectoral fin light green. Dorsal- and anal-fin rays green; fin membranes hyaline. Caudal-fin rays green; fin membranes light green.

Distribution.

Known presently from multiple sites along the northern and northeastern coast of Tasmania, and two sites along the coast of mainland Australia, including Jubilee Point (Victoria; type locality) and Botany Bay (New South Wales) (Fig. 12). The majority of specimens have been collected from subtidal fields of macroalgae, 0-2 meters depth.

Etymology.

Neologism combining the Latin alga and colare, who inhabits the algae, in reference to the habitat preference of the new species. A noun in apposition.

Remarks.

The specimen of "Rat clingfish" illustrated in Hutchins (1994a: 310, fig. 273) represents Barryichthys algicola . An elongate gobiesocid larva (AMS I.48745-008) collected along the coast of New South Wales have been tentatively identified as B. algicola (T. Miskiewicz, pers. comm.)