Spongiopsyllus porthosi, Farias & Santana & Neves & Johnsson, 2024

Farias, Amilcar, Santana, Alisson, Neves, Elizabeth G. & Johnsson, Rodrigo, 2024, Three new species of Spongiopsyllus Johnsson, 2000 (Copepoda: Siphonostomatoida: Entomolepididae) associated with Aplysina cauliformis (Carter, 1882) (Porifera: Demospongiae) from Todos-os-Santos Bay, Northeastern Brazil, European Journal of Taxonomy 968, pp. 37-59 : 43-48

Spongiopsyllus porthosi sp. nov.

urn:lsid:zoobank.org:act:8657923B-746E-4F56-AFE1-031DCF4ECB16

Figs 3–5 , Tables 2, 4

Diagnosis

Body shield dorso-ventrally flattened, pedigerous somite 3 and 4 not fused. Antennule 16-segmented, showing fusion of segments (III–VI, IX–XIII, XXIII–XXVIII), and aesthetasc on segment 14. Antenna with 2 spinules on outer, and 3 spinules on inner margins of exopod segment, and endopod 2-segmented with 2 long and 2 short apical setae. Maxillule with 4 setae on inner lobe, and 4 setae on outer lobe. Maxilliped with endopod 3-segmented, showing 2 setae on first segment, 2 on second and unarmed third segment, setal formula (2,2,0+claw).

Etymology

The tapered morphology of leg 1 endopodal segments, showing sharpened processes, inspired the species name referring to the swordsman ‘Porthos’, one of Alexandre Dumas’ characters from ‘ The Three Musketeers ’, a historical adventure novel written in 1844.

Material examined

Holotype

BRAZIL • ♀; Bahia, Todos-os-Santos Bay, Pedra Cardinal ; 12°50′15″ S, 38°32′58″ W; 20 May 2017; L.C.C. Silvany leg.; manually collected, associated with the sponge Aplysina cauliformis ( Carter, 1882) ; UFBA 3292 .

Allotype

BRAZIL • ♂; same data as for holotype; UFBA 3293 .

Paratype

BRAZIL • 1 ♀; same data as for holotype; UFBA 3297 .

Description

Female

Body length (from cephalosome to the furcal rami) 1220 µm and body greatest width (cephalosome) 870 µm. Prosomal shield flattened ( Fig. 3A ), with radiating bands along outer margin. Pedigerous somites 2–4 free. Urosome ( Fig. 3B ) 4-segmented. Genital double-somite fused with fifth pedigerous somite, 160 µm long, and with length:width ratio 0.9:1. Three postgenital somites present, first and second wider than long, 58 ×84, 20 ×78 µm, respectively; anal somite longer than wide, 130 ×70. Prosome:urosome length ratio 2.7:1. Caudal rami elongate, 130 µm long, with setules along medial-distal inner margin, and armed with 6 setae distally.

Antennule ( Fig. 3C ) slender, 241 µm long (not including setae), and 16-segmented. Length of segments: 58, 25, 27, 7, 9, 13, 10, 10, 12, 9, 11, 12, 12, 14, 7 and 7 µm, respectively. Segmental homologies and setation as follows: I-1; II-2; III–VI-7; VII-2; VIII-2; IX–XIII-7; XIV-1; XV-2; XVI-1; XVII-1; XVIII-1; XIX-2; XX-1; XXI-2+ae; XXII-1; XXIII–XXVIII-7. All setae are naked. Aesthetasc 100 µm long.

Antenna ( Fig. 3D ) 222 µm long (including distal claw); coxa 37 µm long; basis 80 µm long. Exopod 1-segmented, 67 µm long, and with 2 long subequal distal setae and 5 spinules along margins; ornated with setules on distal margin. Endopod 2-segmented; first segment 57 µm long, unarmed, with spinules on outer margin; second segment 27 µm long, ornamented with row of setules along outer margin, and armed with 2 long setae on outer margin, one of them covered with setules, and 2 short naked setae; distal claw slightly curved, 58 µm long.

Oral cone broken ( Fig. 3A ). Mandible comprising stylet and slender 2-segmented palp ( Fig. 3E ) measuring 52 and 64 µm long, respectively. Palp with second segment armed with 2 apical, smooth setae and ornamented with setules along outer margin.

Maxillule ( Fig. 3F ) bilobed; inner lobe 86 µm long, armed with 4 setae, 2 plumose and longer than the others. Outer lobe 40 µm long, armed with 4 setae and ornamented with setules along outer margin; all setae naked.

Maxilla ( Fig. 3G ) with syncoxa and curved claw measuring 143 and 147 µm long, respectively; distal claw tip abruptly curved.

Maxilliped ( Fig. 4A ) 5-segmented, 298 µm long (excluding claw); syncoxa 84 µm long, unarmed; basis 138 µm long, unarmed. Endopod 3-segmented, 22, 23, and 31 µm long, respectively; first and second segment each with 2 naked setae; third segment with curved claw measuring 56 µm long and few setules on outer margin.

P1–P3 ( Fig. 4B–D ) biramous, with 3-segmented rami. P4 ( Fig. 4E ) with 3-segmented exopod and endopod absent. Armature formula below ( Table 2).

First exopodal segments of P1 ( Fig. 4B ) with setules on outer margins; second endopodal segments with setules on both margins, third endopodal segment with setules on outer margin.

First exopodal segments of P2 ( Fig. 4C ) with setules on outer margins, second and third with spinules on outer margins; second endopodal segments with setules on both margins, third endopodal segment with setules on outer margin.

P3 ( Fig. 3D ) basis with spinules on outer margin; distal spines of exopod with long setules on inner margin; endopodal segments with setules on outer margin on first segment, and both margins on second and third segments.

P4 ( Fig. 4E ) with two spinules on outer margin of basis; second and third exopodal segments with spinules on outer margins; third exopodal segment setules on inner margin; distal spines of exopod with long setules on inner margin.

Free exopodal segment of P5 ( Fig. 3A ) elongate, curved, 212 µm long, reaching distal margin of genital double-somite, and armed with 2 distal and an outer plumose medial seta.

Male

Body ( Fig. 5A ) similar but smaller than female. Body length (excluding caudal setae) 740 µm and body width 510 µm. Prosomal shield flattened with radiation bands along outer margin. Pedigerous somites 2–4 free. Pedigerous somite 4 expanded, covering urosome except for caudal rami. Urosome 5-segmented ( Fig. 5B ). Genital somite fused with fifth pedigerous somite, 118 µm long, and length:width ratio 0.8:1. Four postgenital somites; all wider than long (48× 25, 42 × 25, 38 × 12, 42 × 28 µm, respectively. First and second postgenital somites with spine on each distal lateral margin. Prosome:urosome length ratio 2.9:1. Caudal rami elongate, 48 µm long, armed with six setae.

Antennule ( Fig. 5C ) slender, 223 µm long (not including setae), 13 segmented. Length of segments measured along anterior to posterior margins: 42, 17, 22, 6, 8, 12, 11, 25, 11, 9, 18, 23 and 19 µm, respectively. Segmental homologies and setation as follows: I-2; II-2; III–VI-7; VII-2; VIII-2; IX–XIII- 9; XIV-1; XV–XVI-4; XVII-2; XVIII-2; XIX–XX-3; XXI–XXIII-4+ae; XXIV–XXVIII-11; all setae smooth. Aesthetasc 86 µm long. Oral cone ( Fig. 5A ) 350 µm long, reaching genital somite.

All other appendages as in female.

Figures

Fig. 3. Spongiopsyllus porthosi sp. nov.,♀, holotype (UFBA 3292).A. Habitus, dorsal view.B. Urosome. C. Antennule. D. Antenna. E. Mandibular palp. F. Maxillule. G. Maxilla. Scale bars: A = 200 µm; B = 50 µm; C–F = 25 µm; G = 50 µm.

Fig. 4. Spongiopsyllus porthosi sp. nov., ♀, holotype (UFBA 3292). A. Maxilliped. B. L1. C. L2. D. L3. E. L4. Scale bars = 50 µm.

Fig. 5. Spongiopsyllus porthosi sp. nov.,♂, allotype (UFBA 3293). A. Habitus, dorsal view.B. Urosome. C. Antennule. Scale bars: A = 100 µm; B–C = 25 µm.

Tables

Table 2. Spongiopsyllus porthosi sp.nov., armature formula of L1–L4.

	coxa	basis	exopod	endopod
L1	0-1	1-1	I-1; I-1; III,4	0-1; 0-1; 1,5
L2	0-1	1-0	I-1; I-1; III,I,4	0-1; 0-2; 1,2,2
L3	0-0	0-0	I-1; I-1; II,I,4	0-0; 0-1; 0,1,1
L4	0-0	0-0	I-1; I-1; II,I,3	absent