Madeirasquilla tuerkayi, Ďuriš, 2018

Ďuriš, Zdeněk, 2018, Madeirasquilla tuerkayi, a new genus and species of mantis shrimps from Madeira Island, eastern Atlantic (Crustacea: Stomatopoda: Nannosquillidae), Zootaxa 4399 (4), pp. 553-562 : 556-561

Madeirasquilla tuerkayi sp. nov.

( Figs 1–3A, B )

Type material. Holotype: male, MMF 46566, Canico, W off Atalaia Diving Center, Madeira, 32°38.5'N, 16°49.87'W, 14 Apr. 2015, sandy bottom, depth 23 m, in burrow, yabby pump, coll. Z. Ďuriš & P. Wirtz.

Comparative material of Platysquilla eusebia: Machico , Madeira, 32°42.8'N, 16°45.7'W, 14 Apr. 2015, sandy bottom, depth 7–8 m, in burrow, yabby pump, coll. Z. Ďuriš & P. Wirtz:—1 female (TL 43 mm), MMF 46567, fcn 11A-Mdr15.—1 male (TL 43 mm), MMF 46568, fcn 11B-Mdr15.—1 female (TL 42 mm), MNHN-IU- 2015-1650, fcn 11C-Mdr15, GenBank ( Tab.1).—1 male (TL 41.5 mm), 2 females (TL 41.5 mm, 36 mm), UO.11D- Mdr15.

Description of holotype. Body smooth, depressed, loosely articulated; carapace ( Fig. 1A ) with broadly rounded lateral margins, anterolateral angles rounded, not expanded anteriorly; cervical groove indicated on lateral plates only.

Rostral plate ( Fig. 1A ) quadrate, with 3 sharp triangular anterior projections, similar and subequal to each other; plate completely covering base of eyes, apex not extending to cornea; dorsal surface smooth.

Eyes extending beyond 3rd segment of antennular peduncle; cornea ( Fig. 1F ) subglobular but slightly expanded ventrally, oriented obliquely on stalk. Ophthalmic somite anterior margin transverse, straight, with small medioventral spine ( Fig. 1E ). Ocular scales ( Fig. 1A ) fused together into subquadrate lobe with obtusely bifurcate apex.

Antennular peduncle 0.47 CL. Lateral spines of antennular somite slender, directed anteriorly, almost reaching end of anterior rostral teeth. Antennal protopod ( Fig. 1G, H ) with 1 ventral papilla and 2 mesial papillae; antennal scale 0.26 CL.

Mandibular palp absent. Maxillipeds 1–5 each with epipod, fifth epipod smallest.

Raptorial claw ( Fig. 2B ) dactylus with 11 (left) or 12 (right) teeth; outer margin convex, with small acute proximal tooth directed anteriad. Propodus 0.84 of carapace length; occlusal margin pectinate, proximally with 4 movable spines; PI 119, PLDI 256. Carpus with dorsal distal tooth, otherwise unarmed. Merus and ischium unarmed, former slightly longer than latter.

Thoracic somites 6–8 lateral margins subtruncate to broadly rounded ( Fig. 1A ). Thoracic somite 8 sternal keel obsolete.

Pereiopods 1–3 ( Fig. 2C–E ) each with first protopod segment unarmed; endopods 2-segmented, distal segment subcircular (pereiopods 1 and 2), or elongate (pereiopod 3); penes well developed, overreaching distal end of pereiopod 3 protopodite.

Endopod of pleopod 1 (petasma; Fig. 2F, G ) with flattened and elongate tube process, hook process short, longer than broad, posterior endite simple, slightly overreaching hook process.

Pleonite 6 ( Fig. 1B–D ) smooth, unarmed dorsally; lateral margin almost straight, posterolateral angles spiniform, long; hook-shaped ventrolateral spine anterior to uropodal articulation; posterior margin of sternum with pair of spines.

Telson ( Figs 1B–D , 2A ) distinctly broader than long. Dorsal surface smooth, with broadly rounded shield-like dorsal plate bearing slender median spiniform process overhanging posterior margin; marginal armature consisting of 4 pairs of fixed primary teeth with l denticle between each, and 1 pair of low submedian teeth with long movable spines; 4 or 5 spiniform submedian denticles arranged in broadly convex line either side of midline; submedian teeth and denticles placed considerably more ventrally. Ventral surface smooth, anus situated distinctly posterior midlength of telson.

Uropodal protopod ( Fig. 1B, D, I, J ) with 2 straight, ventrally smooth, primary spines, outer longer than inner; inner margin of protopod unarmed adjacent to endopod articulation; dorsal spine prominent, sharp. Exopod proximal segment outer margin with 5 graded movable spines with apices rounded, distalmost spine exceeding midlength of distal segment; distal margin with prominent ventral spine. Exopod distal segment ovate. Endopod elongate, distally rounded, maximum width on distal one-third of length, proximolateral setose dorsal sulcus feebly developed.

Colour. Body ( Fig. 3A, B ) semitranslucent, with rostrum and carapace yellowish, pleon showing more distinct yellow internal median path, each segment with pair of yellow lateral transverse branches associated with bases of appendages. Body and appendages, including raptorial claw ( Fig. 2B ), irregularly black dotted, with larger but diffused submedian black spots on the carapace and dorsodistal parts of uropodal protopod ( Fig. 3A, B ).

Measurements. TL 24.2 mm, CL 3.8 mm, antennular peduncle length 1.8 mm, antennal scale length 1.0 mm. Raptorial claw propodus length 3.2 mm, height 1.3 mm.

Etymology. This species is named in honour of the late Dr. Michael Türkay (1948–2015), for his great and longstanding carcinological contributions covering also crustaceans of the eastern Atlantic, and in particular, Madeira.

Habitat. The present specimen was collected from burrow in a flat sandy bottom at a depth of 23 m.

Distribution. Presently known only from the type locality, Madeira Island, the eastern Atlantic.

GenBank accession number. See Tab. 1.

Key to genera of the family Nannosquillidae (modified from Ahyong 2001)

1. Rostral plate with 3 sharp anterior projections............................................................... 2

- Rostral plate unarmed anteriorly or with single median spine................................................... 4

2. Pleonite 6 with posterolateral spines....................................................................... 3

- Pleonite 6 without posterolateral spines............................................................. Keppelius

3. Pleonite 6 with posterior margin of sternum unarmed............................................... Alachosquilla

- Posterior margin of pleonite 6 sternum with pair of posteriorly directed spines.................. Madeirasquilla gen. nov.

4. Telson with fan-shaped row of slender, posteriorly directed spines, or with patches of numerous small spinules covering pos- terodorsal surface..................................................................................... 5

- Telson without fan-shaped row of posteriorly directed spines, at most with short teeth or transverse row of short, close set spines............................................................................................... 6

5. Cornea subglobular. Antennal protopod with mesial papilla. Submedian denticles of telson in transverse row..... Bigelowina

- Cornea broadened or faintly bilobed. Antennal protopod without mesial papilla. Submedian denticles of telson forming inverted ‘V’ in posterior view................................................................. Acanthosquilla

6. Ischium of raptorial claw with spine on outer distoventral margin................................................ 7

- Ischium of raptorial claw unarmed........................................................................ 8

7. Pleonite 6 with posterolateral spines............................................................. Austrosquilla

- Pleonite 6 without posterolateral spines........................................................... Pullosquilla

8. Dactylus of raptorial claw with 4–6 teeth......................................................... Hadrosquilla

- Dactylus of raptorial claw with 8 or more teeth.............................................................. 9

9. Maxilliped 1–4 with epipod............................................................................ 10

- Maxilliped 1–3 or 1–5 with epipod....................................................................... 11

10. Antennal protopod without papillae............................................................. Nannosquilla

- Antennal protopod with 1 mesial and 2 ventral papillae............................................ Platysquilloides

11. Maxilliped 1–5 with epipod............................................................................ 12

- Maxilliped 1–3 with epipod.................................................................... Mexisquilla

12. Mandibular palp present. Rostral plate cordiform. Telson posterior margin with paired, movable submedian teeth and 1 pair of fixed primary teeth.............................................................................. Coronis

- Mandibular palp absent. Rostral plate subquadrate with short median spine. Telson posterior margin with paired, movable sub- median teeth and more than 1 pair of fixed primary teeth..................................................... 13

13. Raptorial claw with 11–15 teeth on dactylus; sternum of pleonite 6 with 2 posteriorly directed spines.......... Platysquilla

- Raptorial claw with 8 or 9 teeth on dactylus; sternum of pleonite 6 without posteriorly directed spines................. 14

14. Pleonite 6 without posterolateral spines. Telson with ‘false eave’ posteriorly. Outer primary spine of uropodal protopod dis- tinctly shorter than inner................................................................... Nannosquilloides

- Pleonite 6 with posterolateral spines Telson without ‘false eave’ posteriorly. Uropodal protopod with both primary spines sub- equal................................................................................... Victoriasquilla

Figures

FIGURE 1. Madeirasquilla tuerkayi gen. et sp. nov., holotype, male. A, anterior part of body, dorsal. B, posterior part of pleon, telson and uropod, dorsal. C, posterior part of pleonite 6and telson, dorsal. D, pleonite 6, telson, and uropod, ventral. E, anterior region of ophthalmic somite, ventral. F, eye, dorsolateral. G, right antenna, dorsal. H, same, lateral. I, right uropod, dorsal.J, left uropodal protopod, ventral.Scale bars, 1 mm; E – unscaled..

FIGURE 2. Madeirasquilla tuerkayi gen. et sp. nov., holotype, male. A, telson, lateral aspect (right side). B, left raptorial appendage, outer side, C–E, left pereiopods 1–3 (resp.), posterior view. F, right male pleopod 1 endopod, anterior view. G, same, apical processes.Scale bars, 1 mm.

FIGURE 3. Colour patterns of Madeirasquilla tuerkayi gen. et sp. nov. (A, B), and Platysquilla eusebia (Risso, 1816) (C–E) from Madeira Island. A, B, male holotype TL 24.2 mm, habitus and posterior pleon with tail fan (resp.), dorsal. C, ovigerous female, MNHN-IU-2015-1650, TL 42 mm, habitus, dorsal. D, E, pre-ovigerous female, MMF 46567 (TL 43 mm), habitus and posterior pleon with tail fan (resp.), dorsal; orange colour indicates extension of female gonads.Photos, author.