Cubanomysis manuelortizi, Hendrickx & Hernández-Payán & Gómez-Gutierrez, 2023

Hendrickx, Michel E., Hernández-Payán, José Carlos & Gómez-Gutierrez, Jaime, 2023, On a small collection of mysids (Crustacea, Peracarida, Mysida) from the southern Gulf of California, western Mexico, with the description of new species of Mysidium and Cubanomysis, Zootaxa 5360 (2), pp. 194-218 : 207-216

publication ID	https://doi.org/ 10.11646/zootaxa.5360.2.2
publication LSID	lsid:zoobank.org:pub:48554152-4466-4ED7-A50F-4464A1722FE7
DOI	https://doi.org/10.5281/zenodo.10167440
persistent identifier	https://treatment.plazi.org/id/03CF8793-FF97-FFB2-FF2C-BDCEFC65A9D7
treatment provided by	Plazi
scientific name	Cubanomysis manuelortizi
status	sp. nov.

Treatment

Cubanomysis manuelortizi sp. nov. Hendrickx & Hernández-Payán

( Figs. 8‒11 View FIGURE 8 View FIGURE 9 View FIGURE 10 View FIGURE 11 )

Material examined. Holotype, male (CL 1.35 mm, TL 3.14 mm), April 18, 2016, Los Morros (23°27’N, 109°25’W), Cabo Pulmo National Park, Southern Baja California, Mexico, about 5 m depth (ICML-EMU-12984) GoogleMaps . Paratype, male (CL 1.23 mm, TL 2.73 mm), same sample, same locality (ICML-EMU-13275) . Allotype, female (CL 1.42 mm; TL 4.43 mm), May 7, 2017, same locality, about 5 m depth (ICML-EMU-13458) GoogleMaps .

Diagnosis. Third article of antennular peduncle with a small process in middle of distal margin, tipped with a small, slightly curved spine. Mandibular palp median article widening in distal third, 4 simple setae on outer margin, inner margin with 14 regularly set, long, setae; terminal article about 0.5 length of median article, with 6 long, simple setae, 7 barbed setae near apex, and one terminal, longer, curved, barbed seta. Maxillula outer lobe with 8 robust, apical setae. Maxilla distal segment of endopodite with 15 setae, distal four much more robust; two endites armed with 17 long, marginal setae each. Distal seta on the exopod of the male pleopod 4 longer than the rest of the exopod, armed with a single series of spinules covering less than 0.5 of the seta length. Uropodal exopod 7.7 times as long as wide. Male uropodal endopod with 19 robust setae, extending close to the distal tip of the endopod. Telson 1.2 times as long as wide, distally slender, minimum width less than 0.5 telson maximum width. Cleft in the posterior margin of telson shallow, telson of males with 3 robust setae in each lateral lobes and 8 in the cleft (14 in total), setae similar in size.

Description based on the male holotype (ICML-EMU-12984). Carapace elongated, slightly produced anteriorly in a small triangular, blunt process ( Fig. 8A View FIGURE 8 ).

Eyes ( Fig. 8A View FIGURE 8 ) large, semi-oval, cornea wider than long.

Antennular peduncle ( Fig. 8B View FIGURE 8 ) short; article 1 rectangular, longer than articles 2 and 3; article 2 distinctly smaller than other two; article 3 sub-rectangular, almost as wide as long, a small process in middle of distal margin, with a small, slightly curved spine at apex ( Fig. 8B View FIGURE 8 ); processus masculinus ( Fig. 8C View FIGURE 8 ) elongate, with long setae and a series of small, marginal spiny granules.

Antennal peduncle ( Fig. 8D View FIGURE 8 ) shorter than scale; article 1 short, articles 2 and 3 rectangular, almost the same length, article 2 slightly more robust than third. Antennal scale ( Fig. 8D View FIGURE 8 ) approximately 6 times as long as broad, slightly wider near its base, extending beyond the distal edge of the antennal peduncle by almost 0.5 its length, 2- articulated, distal suture well marked, proximal article approximately 3.5 times the length of the distal article; scale extending beyond the distal margin of antennular article 3 by about 0.5 the length of its distal article ( Fig. 8A View FIGURE 8 ).

Mandibular palp ( Fig. 8E View FIGURE 8 ) with proximal article short, naked; median article widening in distal third, long, 4 simple setae on outer margin, inner margin with 14 regularly set, long, setae; terminal article about 0.5 times length of median article, with 6 long, simple setae, 7 barbed setae near apex, and one terminal, longer, curved, barbed seta.

Maxillula ( Fig. 8F View FIGURE 8 ) outer lobe with 8 robust, apical setae; inner lobe with 2 long, robust apical setae (one broken), unbroken seta with some distal spinules.

Maxilla ( Fig. 8G View FIGURE 8 ) with sub-triangular distal segment of endopodite longer than wide, distal margin forming a sharp angle, with 15 setae, distal 4 much more robust; 2 endites armed with 17 long, marginal setae each; proximal-most margin with 3 long, robust marginal setae; exopod longer than wide, armed with 5 long, robust, marginal simple setae increasing in length distally.

Thoracopods missing.

Pleopods 2‒5 ( Fig. 9A‒D View FIGURE 9 ) biramous (pleopod 1 missing), well developed, endopods slightly shorter than exopods (endopod of pleopod 4 missing), proximal lobe (pseudo-branchiae) armed with 5 short, simple setae; exopod of fourth pair ( Fig. 9C View FIGURE 9 ) with one very slender, terminal long seta, about 1.4 times the length of the rest of exopod, armed on one side with spinules covering less than 0.5 times seta length; all exopods and endopods covered with long, plumose setae on both margins.

Uropods ( Fig. 8H View FIGURE 8 ) exopod almost twice as long as telson, 8 times longer than wide; endopod 1/4 shorter than exopod, wider near its base, with well marked statocyst, inner ventral margin armed with 19 robust, well separated setae, increasing slightly in size toward the tip.

Telson ( Fig. 8I View FIGURE 8 ) short, pear-shaped, 1.2 times as long as wide, lateral margins unarmed, strongly constricted posteriorly, maximum (anterior) width about 2.3 times minimum (posterior) width, distal cleft shallow, semicircular, distal margin armed with 14 robust setae, almost of similar size.

Male paratype ( Fig. 10 View FIGURE 10 ) (ICML-EMU-13275). Similar to the holotype, except for the first article of the antennula peduncle ( Fig. 10B View FIGURE 10 ) which is slightly shorter, and the processus masculinus which is also slightly different ( Fig. 10C View FIGURE 10 ) and features a slightly longer series of small spiny tubercles.

Female allotype ( Fig. 11A‒E View FIGURE 11 ) (ICML-EMU-13458). Similar to male except for: the proportionally, slightly longer peduncle of the antenna; the proportionally longer and slender articles 1 and 3 of the antennular peduncle; the presence of 19 setae on the telson posterior margin; and 28 robust setae on uropodal endopod.

Type locality. Los Morros (23°27’N, 109°25’W), Cabo Pulmo National Park GoogleMaps , Southern Baja California, Mexico. Only known locality to date.

Etymology. The new species is named after our friend and colleague Manuel Ortiz Touzet (as a combination of his name, Manuel, and first surname, Ortiz), in recognition for his long career dedicated to the study of Cuban crustaceans, in particular Peracarida, and his extensive contribution to our knowledge of American mysids.

Remarks. In the case of Cubanomysis jimenesi , the type-species of the genus by monotypy ( Băcescu 1968), both the original description and illustrations by Băcescu (1968) and the figures provided by Brattegard (1973) are well detailed and of high quality, and partly included herein (see Figs. 12 View FIGURE 12 , 13 View FIGURE 13 ). Cubanomysis jimenesi is also briefly characterized by Ortiz & Lalana (2017) and Ortiz et al. (2012) (species list and keys). Cubanomysis mysteriosa , the second species described for the genus, has apparently not been reported since its description based on material from southern California (1 male holotype, USNM 184074; 2 males and 2 females, paratypes, USNM 184075). Consequently, the only illustrations available are those provided by Gleye (1982) (see Fig. 14 View FIGURE 14 ). Although these are rather poor in quality, they allow for a comparison with our material.

Compared to males of C. jimenesi , as illustrated by Brattegard (1973: fig. 6B), the unique male specimen of Cubanomysis manuelortizi sp. nov. presents a much shorter antennal peduncle ( Figs. 8D View FIGURE 8 , 10D View FIGURE 10 ), with the distal article reaching 2/3 of the scale proximal article length vs. reaching the tip of the proximal article in C. jimenesi ( Fig. 13B View FIGURE 13 ). However, in the original description ( Băcescu 1968) the antennular peduncle (the sex of the specimen is not indicated) is shorter ( Fig. 12B View FIGURE 12 ), similar to the peduncle of C. manuelortizi sp. nov.: “... A2 a la base beaucoup plus courte que l’écaille” (the antennula has its base much shorter than the scale) ( Băcescu 1968: 233). Compared to C. manuelortizi sp. nov. ( Figs. 8B View FIGURE 8 , 10B View FIGURE 10 ), the male antennal peduncle is about the same length as in C. mysteriosa ( Fig. 14A View FIGURE 14 ). The antennal scale is weakly surpassing the antennal peduncle in C. jimenesi whereas it extends more clearly beyond the peduncle in the two Pacific species.

The male antennula of C. manuelortizi sp. nov. ( Figs. 8B View FIGURE 8 , 10B View FIGURE 10 ) is very similar to the other two known species, although in the case of C. mysteriosa ( Fig. 14A View FIGURE 14 ) comparison is rather difficult due to the bad quality of the original drawing. In C. manuelortizi sp. nov., it clearly matches the male antennula of C. jimenesi as illustrated by Băcescu (1968) and Brattegard (1973) (see Figs. 12A View FIGURE 12 , 13A View FIGURE 13 ), with article 1 rectangular, article 2 less than 0.5 article 1 length, and article 3 squarish, about as long as article 1 but wider. In C. jimenesi , however, as in C. mysteriosa , the third article of the antennular peduncle does not feature a small process tipped by a curved spine at apex of the article, as seen in C. manuelortizi sp. nov. In C. manuelortizi sp. nov. the antennal scale extends beyond the distal margin of antennular article 3 by about 0.5 the length of its distal article ( Fig. 8A View FIGURE 8 ). Comparatively, in C. jimenesi (original description) the antennal scale comes close to the distal margin of article 3 of the antennular peduncle but does not overreach it, while in C. mysteriosa the antennal scale overeaches the antennular peduncle by about the combined length of the antennula 2 distal articles.

The processus masculinus with tuft of long setae is also visible in illustrations of the three species ( Figs. 8C View FIGURE 8 , 10C View FIGURE 10 , 12A View FIGURE 12 , 13A View FIGURE 13 , 14A View FIGURE 14 ), but the lack of details does not allow for a clear comparison with C. manuelortizi sp. nov. In C. manuelortizi sp. nov., there is a series of small, marginal spiny granules on the distal part of the processus masculinus, not illustrated or reported in the two other species.

The maxillae of the three species are similar, but setae on endites of C. jimenesi are less numerous and clearly more robust ( Fig. 12C View FIGURE 12 ) than in C. manuelortizi sp. nov. ( Fig. 8G View FIGURE 8 ); the marginal robust setae on the exopod of C. mysteriosa ( Fig. 14C View FIGURE 14 ) also appear much more robust than in C. manuelortizi sp. nov. ( Fig. 8G View FIGURE 8 ).

In C. manuelortizi sp. nov. the distal seta on the exopod of the male pleopod 4 ( Fig. 9C View FIGURE 9 ) is longer, 1.4 times the length of the rest of exopod, and armed with a single series of spinules covering less than 0.5 the seta length. Comparatively, according to Băcescu (1968), in C. jimenesi this terminal seta is slightly shorter than the rest of the exopod, also with spinules on one margin, but covering only about 1/3 the length of the seta (see Fig. 12D View FIGURE 12 ). In his illustration of C. jimenesi , however, Brattegard (1973) reported a terminal seta much longer than the rest of the exopod and series of spinules on both sides, on less than 1/5 the length of the seta (see Fig. 13C View FIGURE 13 ). In C. mysteriosa , the terminal seta is about as long as the length of the rest of the exopod and also features a series of distal spinules on both margins ( Fig. 14E View FIGURE 14 ).

The shape of the telson in C. manuelortizi sp. nov. ( Fig. 8I View FIGURE 8 , 10F View FIGURE 10 ) and C. jimenesi (see Figs. 12F View FIGURE 12 , 13E View FIGURE 13 ) is similar, with a strong constriction of the distal part, although the posterior portion is slightly narrower in the figure provided by Băcescu (1968) (see Fig. 12F View FIGURE 12 ). The cleft in the posterior margin of the telson, however, is much shallower in C. manuelortizi sp. nov. ( Fig. 8I View FIGURE 8 , 10F View FIGURE 10 ) compared to C. jimenesi , which is deep and V-shaped. According to Băcescu (1968), males of C. jimenesi features 2 robust setae in each lateral lobe, and 10 setae in the cleft (6‒8 in females), 14 in total (10‒12 in females) (see Fig. 12F View FIGURE 12 ), vs. 3 in each lateral lobes and 8 in the cleft (14 in total) in C. manuelortizi sp. nov. ( Figs. 8I View FIGURE 8 , 10F View FIGURE 10 ). Brattegard (1973: 19), however, provided a different arrangement of the telson setae: 2‒4 on each lobe and 4‒6 in the sinus (cleft), making a total of 8 to 14 setae. The series of robust setae on the uropodal endopod is more extended (19 spines) and reaches closer to the endopod tip in C. manuelortizi sp. nov. ( Figs. 8H View FIGURE 8 , 10E View FIGURE 10 ) than in C. jimenesi (10‒11 robust setae, the series ending further away from the tip of the endopod).

The telson is distally slender in C. manuelortizi sp. nov. ( Figs. 8I View FIGURE 8 , 10F View FIGURE 10 ), i.e., less than 0.5 times the telson maximum width, vs. more than 0.5 times the telson maximum width in C. mysteriosa (see Fig. 14G View FIGURE 14 ); the posterior margin also has a shallower cleft in C. manuelortizi sp. nov. compared to C. mysteriosa , and bears 14, robust setae vs. 16‒24 closely set setae in C. mysteriosa ; the series of robust setae on the uropodal endopods is 19 in C. manuelortizi sp. nov., and these setae extend close to the distal tip of the endopod ( Figs. 8H View FIGURE 8 , 10E View FIGURE 10 ), vs. only 10 robust setae in C. mysteriosa , the latter extending slightly beyond the proximal half of the endopod (see Fig. 14F View FIGURE 14 ).

Based on illustrations provided by Gleye (1982), the uropodal exopod is proportionally shorter in C. mysteriosa (length = 6.1 times its width) (see Fig. 14F View FIGURE 14 ) than in C. manuelortizi sp. nov. (length = 7.7 times its width) ( Figs. 8H View FIGURE 8 , 10E View FIGURE 10 ), and the relationship between exopod and endopod length is about 1.17 in C. mysteriosa vs. about 1.24 in C. manuelortizi sp. nov. In C. jimenesi the uropodal exopod length/wide relationship is 6.7 (intermediate between C. manuelortizi sp. nov. and C. mysteriosa ) and the exopod/endopod lengths relationship is 1.24, as in C. manuelortizi sp. nov.

The first two thoracopods of C. mysteriosa , as described by Gleye (1982: fig. 1f, 2a) are strikingly distinct from the “pereiopods” I and II illustrated by Băcescu (1968: fig. 1D, E) for C. jimenesi , the type species of the genus. The diagnosis of Cubanomysis by Băcescu (1968: 232), however, is not very clear in this respect. When additional material of C. manuelortizi sp. nov. is available, and fully compared with the other two known species, including the thoracopods, the diagnosis of Cubanomysis should be revisited.