Munida maatijadakurnaaku, McCallum & Ahyong & Andreakis, 2021

McCallum, Anna W., Ahyong, Shane T. & Andreakis, Nikos, 2021, New species of squat lobsters of the genus Munida from Australia, Memoirs of Museum Victoria 80, pp. 113-152 : 134

Munida maatijadakurnaaku sp. nov.

http://zoobank.org/urn:lsid:zoobank.org:act:354E2119-60D1-

498B-9595-32D05B1968BF

Figures 14, 15

Munida aff. rubiesi Macpherson, 1991 . — Poore et al., 2008.

Type material. Holotype: WAM C78564 , male (rostrum broken; pcl 9.0 mm), Western Australia, south-west of Kalbarri , 27° 56.106' S 113° 4.86' E to 27° 56.646' S 113° 5.28' E, 417–428 m, beam trawl, SS10/2005/98, 4 December 2005.

Description. Carapace. Length 1.2 × greatest width, widest at midlength. Dorsal surface with numerous uninterrupted transverse ridges and secondary transverse striae between main ridges; ridges and striae lined with short, non-iridescent setae and scattered long setae. Gastric region with 4 pairs of epigastric spines, longest pair behind supraocular spines. Hepatic region with short scales; parahepatic spine present. Anterior part of branchial region between cervical groove and postcervical groove with dorsal spine and 5 or 6 main ridges; 1 postcervical spine; posterior part of branchial region with 8 main transverse ridges (excluding posterodorsal ridge) and 5 secondary striae laterally between main ridges. Cardiac region with 5 main transverse ridges. Intestinal region with 2 transverse ridges, posterodorsal ridge distinct, with secondary stria. Frontal margin inclined posteriorly at 106° from midline. Lateral margins slightly convex; anterolateral spine slightly divergent, horizontal, overreaching sinus between rostrum and supraocular spine; hepatic marginal spine distinctly smaller than anterolateral spine; branchial margin with 5 spines. Rostrum broken; supraocular spines 0.4 × pcl, exceeding eyes. Epistomial ridge straight ending slightly anterior to antennal gland; mesial protuberance distinct.

Thoracic sternum. Sternal surface smooth, sternites 4 and 5 with few short striae. Sternite 3 0.4 × width of sternite 4; median length of sternal plastron (sternites 4–7) 0.7 × width of sternite 7. Sternite 4 anterior margin subtriangular, narrowly contiguous with sternite 3.

Abdomen. Somite 2 with 5 pairs of spines on anterior transverse ridge. Somites 2–4 each with 5 or 6 uninterrupted striae behind anterior ridge. Somite 6 posteromedian marginslightly convex, posterolateral margins slightly produced. Telson with numerous transverse squamae; greatest width 1.6 × median length; anterolateral margin slightly concave.

Eye. Maximum corneal diameter 0.4 × distance between anterolateral spines.

Antennule. Basal article (distal spines excluded) overreaching corneae; 2 long, subequal distal spines; 2 lateral spines, proximal smaller, distolateral spine not exceeding distal spines.

Antenna. Article 1 with distomesial spine overreaching distal margin of article 2. Article 2 with strong distomesial spine significantly overreaching distal margin of article 4; distolateral spine reaching distal margin of article 3. Articles 3 and 4 unarmed.

Maxilliped 3. Ischium 1.5 × merus length, with strong flexor distal spine; merus with strong spine on flexor margin and small spine distally, without spine on distal extensor margin.

P1. Length 2.8 × pcl, with long plumose setae and iridescent setae, setae longest on dorsal surfaces. Merus length 1.1 × pcl, with a row of 8 dorsal spines and row of 4 spines on mesial margin; distal spines strong, distomesial spine not reaching midlength of carpus. Carpus 0.4 × merus length, length 1.9 × width. Propodus 1.1 × merus length, fingers 0.6 × total propodus length; pollex with row of 5 spines on lateral margin; dactylus with row of 3 spines on dorsal margin, 5 spines on lateral margin and 1 small subdistal spine.

P2–4. Long, slender, with numerous scales on lateral sides of meri; extensor margins with row of plumose and iridescent setae. P2 length 2.3 × pcl, merus as long as carapace, length about 7 × height, 4.0 × carpus length and 1.9 × propodus length, row of spines on extensor margin, flexor margin row of spines and well-developed distal spine; carpus with 2 small spines and 2 large spines on extensor margin, distal spine on flexor margin; propodus length 5.3 × height, with 9 small movable flexor spines; dactylus compressed, almost straight, as long as propodus length, length 8.6 × height, with 7 movable spines along the flexor margin, distal one-quarter unarmed. P3 with similar spination and article proportions as P2; merus slightly shorter than P2 merus (0.75); propodus and dactylus slightly shorter than those of P2. P4 length 0.6 × P2 length; merus 0.4 × pcl, length 0.6 × P3 merus length; propodus 0.8 and dactylus 0.9 × as long as those of P3.

Etymology. Named maatijada for crawling and kurnaaku for crayfish/yabbie in Nhanda language at the Nhanda Language Day (2 July 2019) at Bundiyarra-Irra Wanga Language Centre in Geraldton; used as a noun in apposition.

Remarks. Despite the broken rostrum in the holotype, Munida maatijadakurnaaku sp. nov. is clearly distinguished by a number of diagnostic characters. It is most similar to M. aequalis Ahyong and Poore, 2004 , from eastern Australia, which also has long and subequal distal spines on the basal antennular article, a subtriangular sternite 4, slender P2–4 dactyli and similar antennal spination. The two species can be distinguished by:

- the supraocular spines overreach the eyes in M. maatijadakurnaaku but do not reach the end of the eyes in M. aequalis

- antennal article 2 has the distomesial spine significantly overreaching article 4 in M. maatijadakurnaaku , but only slightly overreaching article 4 in M. aequalis

- the P2–4 dactyli are as long as their respective propodi in the new species, with only the distal one-quarter unarmed, rather than slightly shorter than the propodus and unarmed on the distal one-third in M. aequalis .

Distribution. Known only from Western Australia, 417– 428 m.

Figures

Figure 15. Munida maatijadakurnaaku sp. nov., 1 male with missing rostrum, pcl 9.0 mm (WAM C78564): A, right P2 dactylus, lateral view; B, left P2, lateral view; C, left P3, lateral view; D, left P4, lateral view; E, left maxilliped 3, lateral view. Scale: A–E = 1 mm.