Batellopsis, Ashrafi & Ďuriš & Anker, 2024

Ashrafi, Hossein, Ďuriš, Zdeněk & Anker, Arthur, 2024, Positive association between PTN polymorphisms and schizophrenia in Northeast Chinese Han population., Zoological Studies 63 (3), pp. 141-149 : 4-12

Family Alpheidae Rafinesque, 1815 Batellopsis gen. nov.

urn:lsid:zoobank.org:act:F226F429-6534-4C08-9E0F-081B5F1BA1FC

Etymology: The new genus’ name is derived from the related alpheid genus Batella , to which the Latin suffix “ opsis ” was added, to allude to morphological similarities and phylogenetic affinities between the two genera. Gender feminine.

Diagnosis: Small alpheid shrimp. Carapace smooth; frontal margin with moderately developed, triangular rostrum and small orbital teeth; pterygostomial angle rounded; cardiac notch well developed. Pleon smooth; first to third pleonites rounded posteroventrally; fourth and fifth pleura subacute posteroventrally; sixth pleonite without articulated plate. Telson strongly tapering posteriorly; dorsal surface with two pairs of submarginal spiniform setae; posterior margin slightly convex, with one pairs of spiniform setae at each angle; anal tubercles absent. Eyes fully concealed in dorsal and lateral views. Antennular peduncle relatively stout; stylocerite slender, with subacute tip, surpassing distal margin of first antennular article; antennular flagellum with fused portion composed of four subdivisions; accessory ramus well developed. Antenna with basicerite moderately stout, armed with small distoventral tooth; scaphocerite with broad blade and strong distolateral tooth; carpocerite slender, slightly exceeding antennular peduncle. Mandible without palp; incisor process distally with four teeth. Third maxilliped slender, pediform, not operculate; coxa with rounded lateral plate; ultimate article slightly tapering distally, its tip armed with three slender spiniform setae. Chelipeds enlarged, unequal in size, asymmetrical in shape, carried extended. Major cheliped with basis short, unarmed; merus slender, smooth, distoventral margin unarmed; carpus short, cup-shaped, with prominent tooth distolaterally; palm robust, swollen, subcylindrical, smooth; fingers subequal in length; pollex cutting edge with groove; dactylus cutting edge with distinct bulge fitting into groove of pollex. Minor cheliped slenderer and weaker than major cheliped; carpus cup-shaped, with one prominent tooth distolaterally and one smaller tooth distodorsally; palm relatively slender, subcylindrical, smooth; fingers subequal in length, no gaping when closed; finger cutting edges blade-like, without bulgechannel system. Second pereiopod with ischium unarmed; carpus composed of five subarticles, third longest; chela elongate, as long as carpus; fingers about 0.3 times as long as palm, with patchily distributed, thick, microserrulate setae; pollex slender, ending in simple tip; dactylus distally with two ungui. Third pereiopod moderately stout; ischium with one spiniform seta; merus slightly inflated, with one spiniform seta, distoventral margin projecting as subtriangular tooth; propodus with numerous spiniform setae on ventral margin; dactylus robust, distinctly subdivided into strongly biunguiculate distal part and stout proximal part, latter with minute teeth on flexor margin. Fourth pereiopod generally similar to third pereiopod, slenderer; merus unarmed. Fifth pereiopod similar to fourth pereiopod, slenderer; ischium and merus unarmed; propodus with distal half furnished with seven transverse rows of microserrulate setae on ventrolateral margin. Uropods with lateral lobe of protopod strongly projecting; distolateral tooth of exopod and small lateral tooth of diaeresis flanking slender spiniform seta, latter slightly surpassing distal margin of exopod. Gill/exopod formula: 5 pleurobranchs (above P1–P5); 1 arthrobranch (at Mxp3); 0 podobranchs; 2 epipods (Mxp1, Mxp2); 4 mastigobranchs (Mxp 3, P1–P3); 4 sets of setobranchs (P1–4); 3 exopods (Mxp 1–3).

Type species: Batellopsis paula sp. nov., by monotypy and present designation.

Distribution: Currently only known from the southwestern Pacific: New Caledonian archipelago (north of Île des Pins).

Remarks: Morphological, ecological and molecular data place Batellopsis gen. nov. within the clade also comprising Bannereus , Batella and Vexillipar , in the above-discussed tree topology ( Fig. 1 ). Even though Batellopsis gen. nov. does not seem to have a single exclusive autapomorphic feature, the genus can be separated from Batella , Bannereus and Vexillipar by the distoventrally armed merus of the third pereiopod ( Fig. 6D ), which is unarmed in the other three genera. However, it must be noted that the distoventral armature of the third (and often also the fourth) pereiopod merus may be an intragenerically variable character in the Alpheidae ( Anker et al. 2006) .

Batellopsis gen. nov. can be separated from Batella by the following features: (1) the incisor process of the mandible distally armed with four relatively enlarged teeth (vs. furnished with setae in Batella ); (2) the mastigobranchs (strap-like epipods) present on the coxae of the third maxilliped and first to third pereiopods (vs. absent in Batella ); (3) the first pereiopods (= chelipeds) carried extended with the dactylus in ventrolateral position (vs. in the dorsolateral position in Batella ); (4) the major cheliped fingers with a bulge-groove system (vs. serrated or armed with one or several stout teeth in Batella ); (5) the second pereiopod fingers furnished with tufts of microserrulate setae in a somewhat irregular pattern (vs. arranged in a fan-shaped pattern in Batella praecipua ; however, less obvious in B. parvimanus and B. leptocarpus ; see Miya and Miyake 1968: fig. 4E; Chace 1988: figs. 17n, 18n; see also below); and (6) the dactylus of the third to fifth pereiopods armed with minute teeth on the flexor margin of the proximal part (homologous to corpus in some palaemonids) (vs. unarmed in Batella ). Furthermore, the arthrobranch at the third maxilliped is reduced in Batella parvimanus ( Miya and Miyake 1968: fig. 3F, as B. bifurcata Miya and Miyake, 1968 ) and absent in B. praecipua ( Ashrafi et al. 2022a: fig 3A, B), whereas it is normally developed in the new genus ( Fig. 4G ); however, its presence or development remains unknown in B. leptocarpus ( Chace 1988) .

As mentioned above, Batellopsis gen. nov. shares with Bannereus (three species, including one undescribed) and Vexillipar the presence of a bulge-groove system on the major or both chelipeds ( Fig. 5A–D ; cf. Bruce 1988; Chace 1988; Anker and Pachelle 2020; A. Anker, pers. obs.), but can be readily distinguished from these two genera by the irregular pattern of microserrulate setae on the fingers of the second pereiopods, which are arranged in a fanlike manner in Bannereus and Vexillipar , similarly to Batella . Whether these peculiar setal fans evolved independently in Batella and in Bannereus / Vexillipar , or whether they evolved in the common ancestor of the hexactinellid-associated alpheid clade and then became more “disorganised” in Batellopsis gen. nov. remains unknown.

In the original description of Vexillipar repandum, Chace (1988) stated that the incisor process of the mandible lacks serrations; however, in his illustration of the mandible ( Chace 1988: fig. 24p), the incisor process appears to be serrated with microscopic teeth. Our examination of two specimens of V. repandum (MNHN- IU-2010-4186) revealed that the incisor process of the mandible in V. repandum is indeed armed with minute irregular teeth, confirming Chace’s (1988) illustration. In contrast, in Bannereus and Batellopsis gen. nov. the incisor process of the mandible is distally armed with four to seven large teeth ( Fig. 4A ; Bruce 1988: fig. 3b). On the other hand, Batellopsis gen. nov. shares the same gill formula as Vexillipar , differing in that aspect from Bannereus . In Batellopsis gen. nov. and Vexillipar , the arthrobranch at the third maxilliped is normally developed or at most slightly reduced, whilst the mastigobranchs on coxae extend from the third maxilliped to the third pereiopod ( Figs. 5 , 6 ; Chace 1988). In contrast, in Bannereus , the arthrobranch is noticeably more reduced, whilst the mastigobranchs are absent in B. anomalus or reduced to only one mastigobranch on the third maxilliped in B. chani ( Bruce 1988; Anker and Pachelle 2020).

Batellopsis gen. nov., Bannereus , and Vexillipar can be differentiated using several characteristics of the chelipeds. In Batellopsis gen. nov. and the two known species of Bannereus , the chelipeds are unequal in size and moderately dissimilar in shape ( Figs. 2 , 5A, 5E ; Bruce 1988: figs. 1, 4a, 4g). In contrast, in Vexillipar , the chelipeds are equal in size and symmetrical in shape ( Chace 1988). Furthermore, the cheliped dactyli are ventrolateral position in Batellopsis gen. nov. and Vexillipar , whereas they appear to be in dorsolateral position in Bannereus ( Fig. 2 ; Chace 1988: fig. 23; Bruce 1988: fig. 1).

Batellopsis paula sp. nov. ( Figs. 2–6 ) urn:lsid:zoobank.org:act:46CB0B7F-5D7A-4584-B5DB-F2886D9012B6

Material examined: Holotype: ovigerous female (CL 4.0 mm); MNHN-IU-2018-4937, north of Île des Pins , New Caledonia; EXBODI sta. CP3841, 22°24'S, 167°24'E; depth 477–503 m; 09.10.2011; coll. MNHN team.

Etymology: The new species is named after Paula Martin-Lefèvre ( MNHN) for her immense help and hospitality during the authors’ visit(s) to the MNHN collection; used as a noun in apposition.

Description: Small alpheid shrimp (holotype: CL 4.0 mm). Carapace ( Fig. 2 ) glabrous, somewhat swollen, not compressed laterally, unarmed. Frontal margin ( Fig. 3A, B ) between rostrum and orbital teeth slightly concave; rostrum moderately developed, triangular in dorsal view, with subacute tip, reaching distal margin of first article of antennular peduncle, slightly wider than long; rostral carina obsolete, reaching posteriorly level of anterior margin of eyes; orbito-rostral process moderately developed; orbital teeth small, subacute, reaching to about mid-length of rostrum, slightly longer than wide, approximately 0.3 times as wide as rostrum, slightly descendant in lateral view; pterygostomial angle rounded, slightly protruding anteriorly; cardiac notch well developed.

Pleon ( Fig. 2 ) glabrous; pleura of first and second pleonites rounded anteroventrally and posteroventrally; third pleuron rounded posteroventrally, fourth and fifth pleura projecting as small subacute tooth posteroventrally; sixth pleuron with small subtriangular projection on posterolateral margin, flanking each side of telson, without articulated plate.

Telson ( Fig. 3C, D ) subrectangular, tapering distally, about 1.8 times as long as proximal width, posterior margin 2.8 times as broad as anterior margin; dorsal surface armed with two pairs of small spiniform setae located approximately at 0.7 and 0.9 telson length, anterior and posterior respectively; posterior margin relatively narrow, furnished with six long plumose setae and two pairs of stouter spiniform setae, mesial about 1.7 times as long as lateral, latter slightly longer than dorsal spiniform setae.

Eyes ( Fig. 3A, B ) fully concealed in both dorsal and lateral views; cornea somewhat reduced; anteromesial margin rounded.

Antennule ( Fig. 3A, B ) with peduncle relatively stout; visible portion of first article slightly longer than broad; stylocerite slender, distinctly overreaching distal margin of first article but falling short of mid-length of second article; second antennular article slightly longer than wide; third article as long as second article, about 1.6 times as long as wide; lateral antennular flagellum thicker than mesial antennular flagellum, fused portion composed of four subdivisions, accessory ramus about half as long as fused portion, with six groups of aesthetascs on distal subdivisions and secondary ramus.

Antenna ( Fig. 3A, B ) with basicerite short, stout, its distoventral margin armed with small, triangular tooth, superior margin rounded; scaphocerite well developed, broad, ovate, slightly overreaching end of antennular peduncle, distolateral tooth stout, distinctly surpassing blade, blade broad, falling short of end of antennular peduncle; carpocerite slightly compressed dorsoventrally, slender, slightly surpassing end of antennular peduncle.

Mandible ( Fig. 4A ) with robust molar process; incisor process distally with four teeth, lateral slightly more robust than mesial; palp absent. Maxillule ( Fig. 4B ) with bilobed endopod, dorsal lobe stronger than and distinctly surpassing ventral lobe, with four long setae, ventral lobe with one seta; dorsal endite almost square-shaped, with long spiniform setae; ventral endite rounded at tip, with slender spiniform and slender setae. Maxilla ( Fig. 4C ) with moderately broad scaphognathite; dorsal endopod simple, with two setae near tip; dorsal endite with shallow cleft; ventral endite short, furnished with several setae. First maxilliped ( Fig. 4D ) with deep cleft between dorsal and ventral endites; dorsal endite with slender spiniform setae; ventral endite without setae; caridean lobe of exopod narrow, furnished with three long, thick, plumose setae; endopod not subdivided, with four long, thick, plumose setae on distal third; epipod shallowly trilobed. Second maxilliped ( Fig. 4E ) with family-typical endopod; exopod with one long, thick seta located at about 0.3 of its length; epipod small, narrow. Third maxilliped ( Fig. 4F, G ) slender, pediform; coxa with shallow, rounded lateral lobe and strap-like epipod (mastigobranch); antepenultimate article slender, about seven times as long as broad; penultimate article slender, about three times as long as broad, about half as long as antepenultimate article; ultimate article slender, slightly tapering distally, approximately eight times as long as proximal width, about as long as antepenultimate article, armed with three spiniform setae on apex; arthrobranch normally developed.

First pereiopods ( Fig. 5 ) enlarged, unequal in size, asymmetrical in shape, carried extended with dactylus in ventrolateral position. Major cheliped ( Fig. 5A–D ) with coxa moderately stout, with strap-like epipod and setobranch; basis and ischium short, unarmed; merus slender, smooth, about four times as long as broad, slightly concave on distal fourth of its length; carpus short, cup-shaped, smooth; palm robust, swollen, subcylindrical, about 1.9 times as long as wide, smooth; fingers relatively stout, subequal in length, about 0.4 times as long as palm, not gaping when closed; pollex with cutting edge with deep groove; dactylus with cutting edge distinctly bulging, this bulge fitting into groove of pollex. Minor cheliped ( Fig. 5E–G ) much weaker and shorter than major cheliped; coxa similar to that of major cheliped; basis and ischium short, unarmed; merus slender, about five times as long as broad, smooth, unarmed; carpus small, cup-shaped, with one prominent tooth distolaterally and one smaller tooth distodorsally; palm somewhat elongate, subcylindrical in cross-section, about three times as long as wide; fingers subequal, about half as long as palm, not twisted, not gaping when closed; cutting edges without bulge-groove system.

Second pereiopod ( Fig. 7A–C ) with all articles relatively slender; coxa with strap-like epipod and setobranch; basis short; ischium about 5.5 times as long as broad, unarmed ventrally; merus about 0.9 times as long as ischium; carpus approximately as long as merus, with five subdivisions, approximate ratio of articles equal to: 2: 1: 1: 1: 3; chela elongate, as long as carpus; palm long, tapering distally, about four times as long as wide; fingers short, about 0.3 times as long as palm, furnished with patchily distributed microserrulate setae, some in tufts; pollex very slender, ending in simple tip; dactylus also slender, ending in two hookshaped ungui.

Third pereiopod ( Fig. 6D, E ) moderately slender; coxa bearing strap-like epipod and setobranch; basis short; ischium short, slightly widening distally, armed with one spiniform seta on ventrolateral surface; merus slightly inflated, about 4.5 times as long as wide, armed with one spiniform setae on ventral margin at about proximal third, distoventral margin projecting as sharp, subtriangular tooth; carpus slightly widening distally, about three times as long as wide, with unarmed distoventral margin; propodus relatively slender, subequal to merus, about eight times as long as wide, ventral margin armed with nine spiniform setae in addition to one distal pair of spiniform setae flanking dactylar base; dactylus robust, subdivided by suture into proximal portion (corpus) and distal portion with two large, sharp ungui, ventral unguis about twice as broad as base of dorsal (main) unguis and slightly shorter, proximal portion with distal half of flexor margin armed with several small teeth, latter decreasing in size towards proximal margin, with most proximal teeth being microscopic. Fourth pereiopod ( Fig. 6F ) generally similar to third pereiopod in proportions, slenderer; coxa without strap-like epipod, with setobranch only; ischium with spiniform seta on ventrolateral surface; merus unarmed, i.e., without spiniform seta on ventral margin and without sharp distoventral tooth; propodus armed with six spiniform setae on ventral margin and one distal pair of spiniform setae flanking dactylar base. Fifth pereiopod ( Fig. 6G, H ) slenderest of three ambulatory legs; coxa without setobranch; ischium unarmed ventrally; merus unarmed; propodus with seven spiniform setae on ventral margin in addition to distal pair of spiniform setae flanking dactylar base, distal half furnished with seven transverse rows of microserrulate setae on ventrolateral surface.

Uropods ( Fig. 3C ) with lateral lobe of protopod strongly projecting; exopod ovoid, distolateral margin with small tooth adjacent to slender spiniform seta, latter slightly exceeding distal margin of endopod; diaresis almost straight, with small lateral lobe; endopod subequal to exopod in length, ovoid, without specific features.

Type locality: North of Île des Pins, New Caledonia.

Distribution: Presently only known from the type locality.

Ecology: The trawl haul contents from the EXBODI station CP3841 shows a significant number of hexactinellid sponges ( Fig. 7 ). Since the holotype of Batellopsis paula gen. et sp. nov. was found in the same lot as several spongicolid shrimp specimens (probably Spongicola sp. ), it can be assumed that this alpheid shrimp, too, was most likely associated with a hexactinellid sponge.

Figures

Fig. 1. Phylogenetic tree constructed using Maximum Likelihood (ML) and Bayesian Inference (BI) methods, based on the concatenation of 16S, CO1, and H3 gene sequences. The numbers above or below each branch indicate the Bootstrap support and Bayesian Posterior Probabilities, respectively. The tree represents the relationship among genera within hexactinellid-associated alpheid clades (ingroup, in colours), with two species of Prionalpheus and two species of Alpheopsis as outgroups (black lines). The genera Batella, Batellopsis gen. nov., Vexillipar and Bannereus are highlighted in yellow, blue, red, and green, respectively. Within each genus (coloured boxes), two main characters are illustrated: left, major cheliped fingers (with bulge-groove system or teeth); right, second pereiopod fingers, showing disposition of setae (organised in fan-like patterns or in simple tufts).

Fig. 6. Batellopsis paula gen. et sp. nov., holotype, ovigerous female (CL 4.0 mm), north of Île des Pins, New Caledonia (MNHN-IU-2018-4937): A, second pereiopod, lateral view; B, same, chela, mesial view; C, same, fingers with some microserrulate setae removed to show details of distal portion of fingers, mesial view; D, third pereiopod, lateral view; E, same, distal portion of propodus and dactylus, lateral view; F, fourth pereiopod, lateral view; G, fifth pereiopod, mesial view; H, same, propodus and dactylus, lateral view.

Fig. 4. Batellopsis paula gen. et sp. nov., holotype, ovigerous female (CL 4.0 mm), north of Île des Pins, New Caledonia (MNHN-IU-2018-4937): A, mandible, lateral view; B, maxillule, lateral view; C, maxilla, lateral view; D, first maxilliped, lateral view; E, second maxilliped, lateral view; F, third maxilliped, mesial view; G, same, proximal half, lateral view.

Fig. 5. Batellopsis paula gen. et sp. nov., holotype, ovigerous female (CL 4.0 mm), north of Île des Pins, New Caledonia (MNHN-IU-2018-4937): A, major cheliped, lateral view; B, same, chela, dorsolateral view; C, same, fingers, lateral view; D, same, mesial view; E, minor cheliped, lateral view; F, same, carpus and chela, mesial view; G, same, lateral view.

Fig. 2. Batellopsis paula gen. et sp. nov., holotype, ovigerous female (CL 4.0 mm), north of Île des Pins, New Caledonia (MNHN-IU-2018-4937): habitus, left lateral view [right side appendages omitted, except for major cheliped].

Fig. 3. Batellopsis paula gen. et sp. nov., holotype, ovigerous female (CL 4.0 mm), north of Île des Pins, New Caledonia (MNHN-IU-2018-4937): A, frontal region (right antennular peduncle broken), lateral view; B, same, dorsal view; C, telson and uropods, lateral view; D, telson, dorsal view.

Fig. 7. Trawl haul from EXBODI station CP3841 (depth: 477–503 m), north of Île des Pins, New Caledonia, type locality of Batellopsis paula gen. et sp. nov. Note the presence of several sponges, predominantly Hexactinellida, including the presumed host of Batellopsis paula gen. et sp. nov. and several spongicolid shrimps and galatheids. Photo credit: Laure Corbari et al., MNHN.