Phyllopodopsyllus tenuis Wells and Rao, 1987

(Figures 1A, B, 2A–C, 3A–D, 4A–F, 5A–C, 6A–C, 7A–D)

Phyllopodopsyllus T. Scott, 1906 in Gómez and Morales-Serna (2014)

Locality

Off Tabasco State (not Campeche State as in Gómez and Morales-Serna 2014, Appendix 2: 121); 18.6169° N, 93.5° W; 36 m depth ; 18.6189° N, 94.00° W; 24 m depth .

Material examined

One adult female, dissected (EMUCOP-11–00); one adult male, dissected (EMUCOP-12–00).

Partial redescription

Female. Habitus fusiform; tapering from posterior margin of cephalothorax to anal somite. Second and third urosomites fused forming genital double-somite, with remains of former division ventrally, completely fused dorsally (Figure 1A, B). Genital double-somite and following urosomite with ventral and dorsal pores and sensilla as figured (Figure 1A, B). Fifth urosomite without pores and sensilla. Anal somite (Figure 1A, B) as long as preceding somite; dorsally (Figure 1A) with two pores and two sensilla, ventrally (Figure 1B) with two pores close to medial cleft; with spinules along posterior margin ventrally; with rounded anal operculum ornamented with spinules along posterior margin (Figure 1A). Caudal rami as figured, elongate, about 3.4 times as long as broad, with longitudinal row of inner setules along distal third; with seven setae as follows: seta I and II in proximal fifth, the former small and ventral to seta II, the latter about four times as long as the former; seta III about halfway along outer margin of caudal ramus, as long as seta II; seta IV as long as seta III, fused to seta V, the latter with swollen proximal part; seta VI inserted on inner distal corner of caudal ramus, half as long as seta IV; seta VII longer than seta III, inserted dorsally at same level as seta III, biarticulated.

Antennule (Figure 2A). Eight-segmented; first segment elongate, about 2.3 times as long as broad; second segment slightly longer than broad, with strong acute process; all setae bare; armature formula as follows: 1(1); 2(7); 3(8); 4(3+(1+ae)); 5(2); 6(3); 7(3); 8(4+(1+ae)).

Antenna (Figure 2B). With basis about 1.7 times as long as broad, with inner longitudinal row of setules; exopod one-segmented, with three elements; distalmost element fused to exopod. First endopodal segment without armature; second endopodal segment with medial and distal hyaline frills; with one slender seta and two spines laterally, and with six elements distally as shown.

Maxilliped (Figure 2C). Syncoxa with spinules and with three inner elements as figured. Basis with some setules and with one seta along inner margin as shown; endopodal segment small, elongate, about three times as long as broad, with long and slender claw and one seta.

P1 (Figure 3 A-C). Only one leg was recovered. Coxa (Figure 3A) large, with some minute spinules medially. Basis (Figure 3A) with outer and inner element as shown. Exopod (Figure 3B) three-segmented; first and second segments with outer minute spinules and outer spine; third segment with four elements. Endopod (Figure 3C) two-segmented; first segment elongate, about 5.7 times as long as broad, with one inner element on distal third; second segment small, about twice as long as broad, with two apical elements.

P2 (Figure 3D). Only the left P2 was recovered completely. Coxa large with spinules as shown. Basis with some inner setules, with outer long seta. Exopod three-segmented; first segment with, second segment without inner seta; third segment with four elements in all (innermost distal seta probably lost during dissection). Endopod twosegmented, reaching about middle of second exopodal segment; first segment unarmed; second segment with three elements (one minute innermost and one medial long seta, and one outermost spiniform element).

P3 (Figure 4 B-E). Both legs badly damaged. Exopod three-segmented; first segment with inner seta (Figure 4D), second segment (Figure 4B) without inner seta; third segment (Figure 4C) with four elements. Endopod two-segmented (Figure 4E); first segment with one inner seta; second segment with three elements (one lost during dissection).

P4. Badly damaged. Endopod (Figure 4A) two-segmented; first segment with one inner seta; second segment with two elements.

P5 (Figure 4F). Large, foliose, forming brood pouch; with 10 elements.

P6 (Figure 1B). Each leg represented by small lobe bearing one long outer seta and two inner elements.

Male. Habitus (Figure 5A, B) fusiform; tapering from posterior margin of cephalothorax to anal somite. Body length measured from anterior tip of rostrum to posterior margin of caudal rami, 270 µm. Rostrum minute (Figure 5A). Surface ornamentation of urosomites as in female. Anal somite and anal operculum

(Figure 5C) as in female. Caudal rami sexually dimorphic, elongate, about 11 times as long as wide, with seven setae (Figure 5C).

Antennule (Figure 6A). seven-segmented, subchirocer; first segment elongate, about 1.3 times as long as wide; second segment nearly as long as wide, with strong acute process. Armature formula difficult to define, most probably as follows: 1(1); 2(11); 3(3); 4(9+(1+ae)); 5(0); 6(0); 7(10+(1+ae)?).

Antenna (Figure 6B). As in female.

P1 (Figure 6C). Badly damaged, as in female.

P2. Badly damaged. Exopod (Figure 7A) as in female. Endopod lost during processing.

P3. Badly damaged. Exopod lost during processing. Endopod (Figure 7C) twosegmented, sexually dimorphic, first segment with one element, second segment with one strong bifid and one slender seta.

P4. Badly damaged. Endopod (Figure 7B) two-segmented; first and second segments with one seta each.

P5 (Figure 7D). Baseoendopod of both legs confluent, with outer basal seta and with three elements on inner endopodal lobe. Exopod with five setae as shown.

Remarks

See below.