Pontonia unidens Kingsley 1880

Pontonia unidens Kingsley

Pontonia unidens Kingsley, 1880:422, pl. 14: fig. 9.—Holthuis 1951b: 150, pl. 47: figs. j, k.

TYPE-LOCALITY.—Key West, Florida.

DISTRIBUTION.—This species of questionable systematic position is known only from the original type-series from Key West, Florida.

*Genus Pseudocoutierea Holthuis, 1951b

Only one Atlantic species is known.

*99. Pseudocoutierea antillensis, new species

MATERIAL.—Saba Bank (Sta. 106–56: 1 ovig. holotype, USNM 135347).

DESCRIPTION.—Rostrum (Figures 11a, b) nearly horizontal, long and slender, subcylindrical, unarmed dorsally and ventrally; tip missing, intact portion overreaching second segment of antennular peduncle; basal portion expanded abruptly to form broad, anterolaterally acuminate eaves over orbits; median, slightly convex carina between orbits extending short distance onto carapace but not as far posteriorly as ridges extending posterolaterally from supraorbital eaves. Carapace broad and depressed, armed only with strong antennal spine arising from anterior margin considerably ventral to obscure orbital angle. Narrow rounded lobe immediately ventral to antennal spine giving bifid appearance to latter in lateral view. Strong ridge curving posterodorsally from antennal spine delimiting depressed orbital region. True anterolateral angle of carapace rounded and separated from antennal spine and lobe by prominent elongate sinus. Nearly longitudinal groove extending posteriorly from anterior margin dorsal to anterolateral angle nearly to posterolateral margin of carapace.

Pleuren of third abdominal somite rounded, entire in female (Figure 11c); pleura of fourth and fifth somites acuminate posteriorly. Sixth somite at least twice as long as fifth and slightly longer than telson, not including terminal spines. Telson (Figure 11d) with anterior pair of lateral spines placed near midlength and posterior pair about midway between anterior pair and distal margin of telson. Intermediate pair of terminal spines more than twice as long as lateral and mesial pairs.

Eyes well developed, cornea not much broader than eyestalk.

Antennular peduncle (Figure 11e) with sharp stylocerite and strong distolateral spine of basal segment reaching about to level of distal fourth of second segment; anterior margin of basal segment produced between distolateral spine and lateral margin of second segment but not reaching midlength of second segment; blunt spine directed distally from near midlength of ventral surface of basal segment (Figure 11f); third segment only slightly longer than second. Lateral antennular flagellum with 2 branches fused for 3 joints; free part of shorter branch consisting of 2 joints.

Antennal scale (Figure 11g) slightly overreaching antennular peduncle, slightly less than three times as long as broad; lateral margin slightly concave in distal two-thirds, distal tooth falling far short of distal margin of strongly produced blade. Antennal peduncle reaching about to midlength of scale; basal segment with strong ventrolateral tooth.

Mouth parts as figured (Figures 11h–m). Mandible with incisor process armed with subapical row of 3 close-set denticles; molar process bearing about 3 teeth or lobes. Second maxilla with mesial lacinia broadly cleft. First maxilliped with well-developed lash on caridean lobe. Second and third maxillipeds without exopods. Third maxilliped reaching slightly beyond lateral spine on basal segment of antennal peduncle.

First pereiopod (Figure 11n) overreaching antennal scale by chela and most of carpus; fingers slightly shorter than palm; carpus slightly longer than chela and shorter than merus. Second pereiopods unequal and dissimilar, right more robust than left. Major cheliped (Figure 11o) overreaching antennal scale by nearly entire chela; fingers (Figure 11p) less than one-third as long as palm, dactyl with large basal tooth closing into depression in fixed finger; carpus less than one-fourth as long as palm; merus nearly three times as long as carpus and about as long as ischium. Minor cheliped of second pair (Figure 11q) overreaching antennal scale by slightly more than chela; fingers not much shorter than palm, unarmed; carpus slightly more than half as long as palm; merus twice as long as carpus and slightly shorter than ischium. Third pereiopod (Figure 11r) overreaching antennal scale by length of dactyl; dactyl (Figure 11s) with obtuse prominence in proximal half of flexor margin; propodus slightly curved, more than four times as long as dactyl; carpus less than one-third as long as propodus; merus somewhat shorter than propodus and more than twice as long as ischium, with triangular prominence near distal end of flexor margin. Fourth pereiopod (Figures 11t, u) reaching about to end of antennal scale; proportionate lengths of podomeres similar to those of third pereiopod, but carpus and ischium slightly shorter. Fifth pereiopod (Figures 11v, w) not reaching quite to end of antennal scale; proportions about as in fourth pereiopod.

Lateral branch of uropod (Figure 11d) without distinct movable spine between distolateral tooth and blade.

SIZE.—Carapace length of unique ovigerous female 1.7 mm. Few eyed eggs (probably most have been shed) about 0.3 mm long.

HABITAT.—Dredged in 13 meters, together with numerous antipatharians and gorgonians.

TYPE-LOCALITY.—Saba Bank at 17°28′N, 63°13′W.

DISTRIBUTION.—Known only from the type-locality.