Phoxokalliapseudes shandongensis, Tzeng & Ma & Li, 2022

Tzeng, You-Wei, Ma, Lin & Li, Xinzheng, 2022, Three new species of Apseudomorpha (Crustacea, Tanaidacea) from Jiaozhou Bay, the Yellow Sea, and the South China Sea off coasts of China, ZooKeys 1096, pp. 119-160 : 119

Phoxokalliapseudes shandongensis sp. nov.

Figs 6 , 7 , 8 , 9 , 10

Type material.

Holotype: MBM287298, one non-ovigerous female, 6.8 mm; the Yellow Sea, 19 June 2019, from sand-gravel substrate at depth of 33 m, 35°59'N, 121°00'E. Allotype: MBM287295, male, 6.1 mm, partially dissected and body parts preserved in 75% alcohol; Jiaozhou Bay, Qingdao, Shandong Province, China, 4 February 2018, from muddy substrate with shell fragments at depth of 4 m, 36°06'N, 120°17'E. Paratypes: MBM287294, one non-ovigerous female, 6.9 mm, completely dissected and body parts preserved in 75% alcohol; Jiaozhou Bay, Qingdao, Shandong Province, China, 20 February 2004, from mud-sandy substrate at depth of 5 m, 36°02'N, 120°14'E. MBM287296, one non-ovigerous female, 6.5 mm, partially dissected and body parts preserved in 75% alcohol; Jiaozhou Bay, Qingdao, Shandong Province, China, 5 February 2007, from muddy substrate at depth of 3 m, 36°10'N, 120°20'E. MBM287297, one non-ovigerous female and one male; Jiaozhou Bay, Qingdao, Shandong Province, China, 9 August 2004, from muddy substrate at depth of 6 m, 36°02'N, 120°14'E. MBM287299, one non-ovigerous female, 6.5 mm; the Yellow Sea, 26 November 2019, sand-gravel substrate with shell fragments at depth of 36 m, 34°59'N, 120°59'E. MBM287300, four males; the Yellow Sea, 26 November 2019, muddy substrate at depth of 38 m, 34°59'N, 121°30'E.

Other material.

MBM147028, one female; Jiaozhou Bay, Qingdao , Shandong Province, China, 2 August 1964, from muddy substrate at depth of 7 m, 36°08'N, 120°15'E . MBM032073, four males; the Yellow Sea , 23 January 1959, from mud-sandy substrate at depth of 41 m, 38°45'N, 122°43'E . MBM147063, one male and one female; Jiaozhou Bay, Qingdao , Shandong Province, China, 4 August 1964, from mud-sandy substrate at depth of 21 m, 36°08'N, 120°15'E . MBM146415, two females; Jiaozhou Bay, Qingdao , Shandong Province, China, 4 August 1964, from muddy substrate at depth of 7 m, 36°08'N, 120°15'E . MBM146430, one female; Jiaozhou Bay, Qingdao , Shandong Province, China, 2 August 1964, from muddy substrate at depth of 9 m, 36°08'N, 120°15'E . MBM146420, one female; Jiaozhou Bay, Qingdao , Shandong Province, China, 4 August 1964, from mud-sandy substrate with gravels at depth of 23 m, 36°08'N, 120°15'E . MBM146419, one female; same collection data as MBM147028. MBM147100, two females; Jiaozhou Bay, Qingdao , Shandong Province, China, 18 August 1964, from muddy substrate at depth of 5 m, 36°08'N, 120°15'E . MBM030026, one female, Yellow Sea , 20 October 1959, from muddy substrate at depth of 17 m, 37°51'N, 121°58'E .

Type locality.

Jiaozhou Bay, Qingdao, Shandong Province, China, and adjacent Yellow Sea area.

Etymology.

The name is derived from Shandong, where the species was collected around Shandong Peninsula.

Diagnosis.

Non-ovigerous female. Antennule peduncle article 1 inner margin with row of five spiniform setae on distal half, and two long ventral subdistal spiniform setae. Antenna peduncle article 1 inner extension with six distal plumose setae. Maxilla with one small spiniform seta near outer margin. Cheliped basis with two small ventral spiniform setae. Pereopod 1 propodus with two dorsal and six ventral spiniform setae. Pereopod 6 propodus with five long ventral spiniform setae; dactylus long, 3.8 × as long as propodus. Pleopod exopod inner margin with one subproximal apophysis. Uropod basal article with one inner distal spiniform seta. Male. Similar to female except pereonites 2-5 with one hyposphenia, and one robust spiniform seta on each hyposphenia. Each pleonite with one hyposphenia. Antennule peduncle article 1 robust, with one ventral spiniform seta; inner flagellum 5-articled. Cheliped fixed finger incisive margin with two large triangular apophyses. Pereopod 6 propodus with three or four long ventral spiniform setae; dactylus very long, 4.6 × as long as propodus.

Description.

Female (non-ovigerous paratype MBM287294). Body (Fig. 6A ) dorsoventrally flattened, 6.9 mm long, 5.8 × as long as broad. Carapace less than 0.2 × as long as total body length, as long as broad, rostrum rounded, lateral margin with one simple seta midway. Pereon half as long as total body length, each pereonite in similar width, slightly broader than carapace, anterolateral margin with one simple seta and several setules; pereonites 1-6 0.5, 0.5, 0.6, 0.8, 0.7, 0.4 × as long as broad, respectively. Pleon 0.2 × as long as total body length, each pleonite in similar width, slightly broader than pereonites, with eight or nine plumose setae on blunt lateral margin, one anterolateral simple seta on dorsal surface. Pleotelson posteriorly tapering and distally bifurcate, ca. as long as three pleonites combined, slightly broader than long, with two distal plumose setae.

Antennule (Fig. 7A ) peduncle article 1 ~ 0.4 × as long as total antennule length, 2.7 × as long as broad, with ten simple setae and four broom setae along outer margin, inner margin with six simple setae on proximal half, two simple setae, and a row of five spiniform setae on distal half, and two long ventral subdistal spiniform setae; article 2 0.3 × as long as peduncle article 1, 1.7 × as long as broad, distal half with three outer, five inner simple setae, and two ventral broom setae; article 3 half as long as article 2, with three distal simple setae; article 4 0.7 × as long as article 3, with one distal simple seta; outer flagellum longer than peduncle article 1, 11-articled, each article with at most four distal simple setae, articles 4, 6, and 7 each with one distal aesthetasc; inner flagellum 6-articled, articles 1-4 each with one distal simple seta, article 5 naked, article 6 with three distal setae.

Antenna (Fig. 7B ) article 1 outer margin with one distal simple seta, inner extension long, covered with setules, with six distal plumose setae; article 2 inner margin covered with setules, squama with six simple setae along outer to distal margin, and spinules along inner margin; article 3 very short, with two inner plumose setae; article 4 nearly half as long as antenna, with one outer broom seta midway, a row of ten plumose setae along inner margin, and a row of 20 ventral plumose setae; article 5 inner and outer margin both with four simple setae, distal margin with five dorsal simple setae and two ventral plumose setae; articles 6 and 7 both with five distal simple setae and two ventral plumose setae; article 8 with one distal simple and two ventral plumose setae; article 9 with two ventral plumose setae; article 10 with five distal simple setae.

Labrum (Fig. 7C , figure and description based on non-ovigerous female paratype, MBM287296, 6.5 mm long) distal margin rounded, covered with numerous setules; clypeus with two robust and two smaller cusps.

Left mandible outer margin with one conspicuous apophysis; both incisor and lacinia mobilis (Fig. 7D , figure based on MBM287296) distal margin denticulate; setal row with five serrate setae; molar distal margin crenulate; palp with 29 long plumose setae along inner margin and one distal spiniform seta. Right mandible (Fig. 7E ) similar to left mandible but without lacinia mobilis, incisor (Fig. 7F , figure based on MBM287296) with two large distal denticles.

Labium palp (Fig. 8A ) subrectangular, 1.5 × as long as broad, covered with setules, with one small spine-like apophysis on inner distal corner.

Maxillule (Fig. 8B ) inner endite covered with numerous long setules, with four distal plumose setae; outer endite covered with numerous long setules, with a row of spinules along outer margin, ten spiniform setae on distal margin, two subdistal plumose setae, and one distinct concavity (arrow) on outer distal corner.

Maxilla (Fig. 8C ) outer lobe of movable endite with five plumose setae; inner lobe of movable endite with row of 15 distally blunt setae, and two comb-like setae along distal margin; outer lobe of fixed endite with a row of 15 simple setae, four plumose setae, and two robust and one smaller serrate seta; inner lobe of fixed endite with five distally serrate setae and a row of 17 plumose setae; outer margin and sub-outer surface covered with spinules, with one sub-outer spiniform seta (arrowed).

Maxilliped (Fig. 8D ) basis with a row of 25 plumose setae along outer margin; endite (Fig. 8E ) covered with setules entirely, with ten plumose setae on distal margin, two robust coupling hooks on inner margin, and eight setulose and distally serrate setae on inner fold; palp article 1 with four simple setae on inner margin and one simple seta on outer margin; article 2 with two rows of numerous long plumose setae along inner margin, and four subdistal simple setae on outer margin; articles 3 and 4 both with two rows of numerous long plumose setae along inner margin.

Epignath not examined.

Cheliped (Fig. 9A ) exopod 3-articled, article 3 with two distal plumose setae; basis ~ 1.5 × as long as broad, ventral margin with one spiniform seta midway, three meddle simple setae, one subdistal spiniform seta, and two subdistal simple setae; merus with one ventral simple seta, anterior corner protruded and rounded, anterior margin crenulate, with three simple setae; carpus ~ 3.5 × as long as broad, with two rows of long plumose setae along ventral margin, both rows with ~ 40 setae, dorsal margin with three short and one longer simple setae on distal half, anteroventral corner with four outer simple setae; propodus and fixed finger combined nearly as long as carpus, 2.2 × as long as broad, palm 1.6 × as long as broad, with a row of 15 inner plumose setae and a cluster of 11 simple setae on anterodorsal corner near insertion of dactylus, fixed finger with 17 simple setae on ventral margin or subventral surface, 17 simple setae and an intensive row of small denticles along incisive margin, a row of 12 outer and four inner simple setae near insertion of dactylus; dactylus plus unguis 4.5 × as long as broad, slightly curved, with nine outer and four inner simple setae, and a row of 15 small spiniform setae along incisive margin.

Pereopod 1 (Fig. 9B , figure and description based on MBM287296) exopod 3-articled, article 3 with two distal plumose setae; coxa with one simple seta on blunt apophysis; basis ~ 2.2 × as long as broad, dorsal margin with one simple and two broom setae on proximal half, ventral margin with one midway, two subdistal simple setae, and one robust subdistal spiniform setae, and one simple seta on subventral surface; ischium with one ventral simple seta; merus 0.8 × as long as basis, 1.9 × as long as broad, distal margin with one dorsal simple seta, one dorsal spiniform seta, one outer simple seta, and one ventral spiniform seta, ventral margin with eight simple setae; carpus short, ca. half as long as merus, slightly longer than broad, dorsal margin with a cluster of six subdistal simple setae and one robust distal spiniform seta, ventral margin with seven subdistal simple setae and two spiniform setae, outer surface with a cluster of three short simple setae; propodus 0.7 × as long as carpus, 1.3 × as long as broad, dorsal margin with a row of seven subdistal simple setae and two distal spiniform setae in unequal size, ventral margin with eight simple setae and six spiniform setae, outer surface with four short subproximal simple setae; dactylus 0.7 × as long as propodus, covered with intensive long sensory setae.

Pereopod 2 (Fig. 9C ) basis 2.5 × as long as broad, dorsal margin with two simple setae and one broom seta, ventral margin three simple setae and one broom seta; ischium with three ventrodistal simple setae; merus 0.4 × as long as basis, 1.7 × as long as broad, dorsal margin with one subdistal simple seta, ventral margin with one subdistal simple seta and one subdistal spiniform seta; carpus slightly shorter than merus, 1.5 × as long as broad, dorsal margin with a cluster of two longer and two short distal simple setae, and one outer distal spiniform seta, ventral margin with four simple setae and four spiniform setae on distal half; propodus slightly shorter than carpus, 2.1 × as long as broad, with one dorsal broom seta midway, and a row of two distal simple setae and six spiniform setae, ventral margin with three long and three shorter simple setae, and a row of five spiniform setae on distal half; dactylus plus unguis long and slender, 2.2 × as long as propodus, without sensory lobe.

Pereopod 3 (Fig. 9D ) basis 2.7 × as long as broad, dorsal margin with one simple and two broom setae midway, ventral margin with one distal simple seta and one distal spiniform seta; ischium with four ventrodistal simple setae; merus 0.4 × as long as basis, 1.6 × as long as broad, ventral margin with three simple setae and two spiniform setae on distal half, outer surface with one subdistal simple seta; carpus slightly shorter than merus, 1.4 × as long as broad, dorsal margin with one distal spiniform seta and three distal simple setae, ventral margin with three simple setae and four spiniform setae on distal half; propodus and dactylus similar to those of pereopod 2.

Pereopod 4 (Fig. 10A ) basis 2.4 × as long as broad, dorsal margin with three subproximal broom setae, one midway and two subdistal simple setae, ventral margin with one subproximal broom seta; ischium with four ventrodistal simple setae; merus short, 0.3 × as long as basis, 1.3 × as long as broad, ventral margin with three subdistal simple setae and two subdistal spiniform setae; carpus 1.4 × as long as merus, 1.9 × as long as broad, with two dorsodistal simple setae, a row of eight outer spiniform setae, a row of eight inner spiniform setae, and three ventral simple setae, ventral half covered with setules; propodus slightly shorter than carpus, 2.7 × as long as broad, with one large dorsoproximal broom seta and a row of five small dorsodistal leaf-like spiniform setae (Fig. 10B ), a row of eight outer, eight inner spiniform setae and six simple setae along ventral to distal margin, ventral margin covered with setules; dactylus 0.4 × as long as propodus, with nine distal simple setae.

Pereopod 5 (Fig. 10C ) basis 2.5 × as long as broad, dorsal margin with three broom setae on proximal half and three simple setae on distal half, ventral margin with a cluster of three distal simple setae, and two simple setae on distal half; ischium, merus, propodus and dactylus very similar to those of pereopod 4 but merus with seven inner spiniform setae.

Pereopod 6 (Fig. 10D ) basis 3.7 × as long as broad, with nine dorsal and three ventral plumose setae, and three ventral subdistal simple setae; ischium with two ventrodistal simple setae; merus short, 0.2 × as long as basis, slightly as long as broad, with three dorsal plumose setae and one ventral simple seta; carpus 2.7 × as long as merus, 2.4 × as long as broad, with six dorsal plumose setae and four ventral simple setae, ventral margin covered with setules; propodus (Fig. 10E ) ~ 0.7 × as long as carpus, almost twice as long as broad, with five long ventral spiniform setae, a row of 27 short serrate setae along ventral to distal margin, and one dorsodistal spiniform seta; dactylus (Fig. 10E ) long and slender, 3.8 × as long as propodus.

Pleopods (Fig. 10F ) basal article with four inner plumose setae; exopod with 20 plumose setae, inner margin with one subproximal protrusion (arrowed); endopod with 22 plumose setae, innermost seta (Fig. 10G ) robust, distally branched and ringed.

Uropod (Fig. 10H , figure and description based on MBM287296) basal article 2.7 × as long as broad, with two outer, one inner distal simple seta, and one inner distal spine; exopod 3-articled, article 3 with four distal simple setae; endopod 22-articled, each article naked or with at most five distal simple setae, article 2 with three distal broom setae, articles 4, 6, and 11 each with two distal broom setae.

Male (allotype MBM287295). Similar to female with following variations: body (Fig. 6B ) less slender, 6.1 mm long, 4.8 × as long as broad. Carapace ~ 0.2 × as long as total body length, slightly broader than long, lateral margin with one simple seta midway. Each pereonite with 1-3 anterolateral simple setae, pereonites 1-5 each with one hyposphenia (Fig. 6C ), and one robust spiniform seta on each hyposphenia, pereonite 6 with genital cone; pereonite 1 conspicuously broader than subsequent pereonites, 1.2 × as broad as pereonite 2, 0.4 × as long as broad; pereonites 2-6 in similar width, relatively short, 0.5, 0.5, 0.5, 0.5, 0.3 × as long as broad respectively. Each pleonite ca. as wide as pereonite 1, with one hyposphenia, one dorsolateral simple seta and 6-10 lateral plumose setae.

Antennule (Fig. 7G ) peduncle article 1 robust, 0.4 × as long as total antennule length, 2.2 × as long as broad, outer margin with eight simple and five broom setae, inner margin seven simple and three broom setae, and one small ventral spiniform seta near inner distal corner; article 2 0.4 × as long as article 1, 1.4 × as long as broad, with six inner simple setae, two simple and two broom ventral setae; peduncle article 3 0.5 × as long as peduncle article 2, slightly as long as broad, with one outer subdistal and three inner distal simple setae; peduncle article 4 0.7 × as long as article 3, distal margin with two inner simple setae; outer flagellum longer than peduncle article 1, 11-articled, article 1 with 15 distal aesthetascs; article 2 with ~ 15 distal aesthetascs and two distal simple setae, article 3 with 11 distal aesthetascs and two distal simple setae, articles 4 and 5 both with six distal aesthetascs and two distal simple setae, articles 6, 7 and 9 each with one distal aesthetasc and two distal simple setae, articles 8 and 10 naked, article 11 with four distal simple setae; inner flagellum 5-articled, articles 1-3 each with one distal simple seta, article 4 with two distal simple setae, article 5 with four distal simple setae.

Antenna article 1 inner extension with six distal plumose setae.

Cheliped (Fig. 9E ) exopod 3-articled, article 3 with two distal plumose setae; basis ~ 1.4 × as long as broad, with two long outer setae, ventral margin with one spiniform seta midway, two distal short simple setae and one distal spiniform seta; merus with three ventral simple setae, anterior corner protruced and rounded, anterior margin crenulate, with three simple setae; carpus 2.6 × as long as broad, dorsal margin with four subdistal simple setae, ventral margin with two rows of long plumose setae, outer row with 35 plumose setae, inner row with 32 plumose setae; propodus large and robust, combined with fixed finger nearly as long as carpus, 1.8 × as long as broad, palm 1.3 × as long as broad, with a row of 15 inner plumose setae, a cluster of 17 anterodorsal simple setae and a row of 13 outer simple setae near insertion of dactylus, fixed finger with five ventral simple setae, incisive margin with two strong triangular apophyses, a row of eleven simple setae, and a row of seven small spiniform setae; dactylus plus unguis 3.7 × as long as broad, slightly curved, dorsoproximally expanded, with nine outer setae and a row of ten small spiniform setae along incisive margin.

Pereopod 6 (Fig. 10I ) basis ~ 4.1 × as long as broad, dorsal margin with seven plumose setae, ventral margin with three plumose setae midway and four subdistal simple setae; ischium with three ventral subdistal simple setae; merus short, 0.2 × as long as basis, slightly longer than broad, with three dorsal plumose and two ventral simple setae; carpus 2.3 × as long as merus, 2.1 × as long as broad, with seven dorsal plumose and four ventral simple setae; carpus 0.7 × as long as merus, 1.8 × as long as broad, with three (on left pereopod 6) or four (on right pereopod 6) long ventral spiniform setae, a row of 24 short serrate setae along ventral to distal margin, and one dorsodistal spiniform seta; dactylus very long and slender, 4.6 × as long as propodus.

Some other morphological characters of males given in Table 2 .

Remarks.

Seven species have been reported for the genus Phoxokalliapseudes , all from the western Pacific, i.e., P. aculeatus Wi, Kang & Soh, 2017 (southwestern Korea), P. cinctus Wi, Kang & Soh, 2017 (southern Korea), P. gibbus Wi, Yu & Kang, 2019 (Jeju Island, Korea), P. gobinae Bamber, 1998 (Brunei and Sabah; Bamber 2013), P. multiarticulus Guţu, 2006 (Darwin, northern Australia), P. singaporensis Drumm & Heard, 2011 (Singapore), and P. tomiokaensis Shiino, 1966 (Kyushu, Japan). The eighth species, Phoxokalliapseudes shandongensis sp. nov. from the present study, is geographically closest to P. aculeatus and P. gibbus .

Morphologically, Phoxokalliapseudes shandongensis also closely resembles P. gibbus , by having six distal plumose setae on inner extension of antenna article 1, two ventral spiniform setae on cheliped basis, two large triangular (conical) apophyses on incisive margin of male cheliped fixed finger, similar female and male pereopod 6 dactylus to propodus length ratio, and one subproximal protrusion on inner margin of each pleopod exopod. However, P. shandongensis can be distinguished from P. gibbus by several significant differences: 1) female antennule peduncle article 1 with two long and conspicuous ventral spiniform setae and five smaller spiniform setae on inner margin, vs. only one ventral spiniform seta in P. gibbus ; 2) with six ventral spiniform setae on pereopod 1 propodus, vs. nine in P. gibbus ; 3) with five ventral spiniform setae on pereopod 6 propodus, vs. six in P. gibbus ; 4) with one inner distal spiniform seta on uropod basal article (Figs 7A, B , 9A, B, E , 10D-I , Table 2 ; Wi et al. 2019: figs4C, E, 5C-F, H, I, 6F, G, 7E, F, H, I).

Among Phoxokalliapseudes species, only P. shandongensis and P. gobinae have one inner distal spiniform seta on uropod basal article. However, the male of P. shandongensis have two large triangular (conical) apophyses on incisive margin of cheliped fixed finger, easily distinguished from the male of P. gobinae with one distal square and one triangular (conical) apophysis. In addition, the presence of two ventral spiniform setae on female cheliped basis can also differentiate the new species from P. gobinae (Fig. 9A, E , Table 2 ; Bamber 1998: fig 9A, B; Drumm and Heard 2011: figs 22F, 24D).

Figures

Figure 6. Phoxokalliapseudes shandongensis sp. nov. Paratype (MBM 287294), non-ovigerous female A body dorsal view. Allotype (MBM 287295), male B body dorsal view C pereonites 1 - 2 lateral view. Scale bar: 2 mm.

Figure 7. Phoxokalliapseudes shandongensis sp. nov. Paratype (MBM 287294), non-ovigerous female A right antennule B left antenna E right mandible. Paratype (MBM 287296), non-ovigerous female C labrum D left mandible incisor, lacinia mobilis and setal row F right mandible incisor and setal row. Allotype (MBM 287295), male G left antennule. Scale bars: 0.2 mm (A-C, E, G); 0.1 mm (D, F).

Figure 8. Phoxokalliapseudes shandongensis sp. nov. Paratype (MBM 287294), non-ovigerous female A labium palp B maxillule endites C maxilla D maxilliped E maxilliped endite. Scale bars: 0.1 mm (A, E); 0.2 mm (B-D).

Figure 9. Phoxokalliapseudes shandongensis sp. nov. Paratype (MBM 287294), female A right cheliped C right pereopod 2 D right pereopod 3. Paratype (MBM 287296), non-ovigerous female B left pereopod 1. Allotype (MBM 287295), male E right cheliped. Scale bars: 0.2 mm (A-E).

Figure 10. Phoxokalliapseudes shandongensis sp. nov. Paratype (MBM 287294), non-ovigerous female A right pereopod 4 B dorsodistal spiniform seta on pereopod 4 propodus C right pereopod 5 D right pereopod 6 E left pereopod 6 propodus and dactylus F left pleopod 2 G pleopod endopod innermost seta. Paratype (MBM 287296), non-ovigerous female H right uropod. Allotype (MBM 287295), male I left pereopod 6. Scale bars: 0.2 mm (A, C, D, H, I); 0.1 mm (E, F, G).