Mastigodiaptomus suarezmoralesi, Gutiérrez-Aguirre & Cervantes-Martínez, 2013

Gutiérrez-Aguirre, M. A. & Cervantes-Martínez, A., 2013, Diversity of freshwater copepods (Maxillopoda: Copepoda: Calanoida, Cyclopoida) from Chiapas, Mexico with a description of Mastigodiaptomus suarezmoralesi sp. nov., Journal of Natural History (J. Nat. Hist.) 47 (5 - 12), pp. 479-498: 485-492

publication ID

http://doi.org/ 10.1080/00222933.2012.742587

persistent identifier

http://treatment.plazi.org/id/03853E42-FFEB-FFD0-BAB7-FF3EFCFE4DEC

treatment provided by

Felipe

scientific name

Mastigodiaptomus suarezmoralesi
status

sp. nov.

Mastigodiaptomus suarezmoralesi   sp. nov.

( Figures 4–7 View Figure 4 View Figure 5 View Figure 6 View Figure 7 )

Material examined

Holotype. Adult female collected 15 April 2000, from Laguna de Montebello 1, Chiapas, Mexico (16 ◦ 06 ′ 42 ′′ N, 91 ◦ 41 ′ 32 ′′ W), deposited at the Colección de Referencia de El Colegio de la Frontera Sur, registered under number ECO-CHZ-07545. GoogleMaps  

Allotype. Adult male from Laguna de Montebello 1, Chiapas, Mexico, deposited at the Colección de Referencia de El Colegio de la Frontera Sur, registered under number ECO-Z-07546.  

Paratypes. Five adult males ( CNCR 26675), and five adult females ( CNCR 26676) from Laguna de Montebello 1, Chiapas, Mexico, preserved in 70% ethanol with a drop of glycerine, deposited at Colección Nacional de Crustáceos ( CNCR) del Instituto de Biología , Universidad Nacional Autónoma de México. Eleven adult females and eight adult males from Laguna Tziscao , Chiapas, Mexico (16 ◦ 05 ′ 19 ′′ N, 91 ◦ 40 ′ 10 ′′ W) collected 15 April 2000, preserved in 70% ethanol with a drop of glycerine, deposited at the Colección de Referencia de El Colegio de la Frontera Sur , registered under number ECO-CHZ-05522. Ten adult females and ten adult males from Laguna Escondida, Chiapas, Mexico (16 ◦ 06 ′ 43 ′′ N, 91 ◦ 40 ′ 36 ′′ W) collected 15 April 2000, preserved in 70% ethanol with a drop of glycerine, registered under number ECO-CHZ-05523. Two adult females and two adult males used for SEM GoogleMaps   .

Type locality

Laguna de Montebello 1, Chiapas, southeastern Mexico; 16 ◦ 06 ′ 42 ′′ N, 91 ◦ 41 ′ 32 ′′ W, 15. April. 2000, within Lagunas de Montebello National Park GoogleMaps   .

Description

Female. Average length excluding caudal setae 1022.7 ± 26.8 µm; range 1000–1070 µm, n = 20. Prosome slightly wider at distal third, symmetrical in dorsal view ( Figure 4A View Figure 4 ). In lateral view, the body is thin and arched downwards at level of second to fourth pediger, thin, without dorsal hump on fifth pediger ( Figure 4B View Figure 4 ). Long, asymmetrical rostral points: right slightly longer than left ( Figure 4C View Figure 4 ). Asymmetrical thoracic wings, left longer than right, both wings bearing two large spines directed posteriorly ( Figure 4D,E View Figure 4 ). Three-segmented urosome; genital double somite asymmetrical: right margin slightly projected, bearing one large spine, left margin almost straight with one small spine; genital field bearing one upper convex plate over one semi-rectangular plate, and rounded protuberance on genital opening ( Figures 4F View Figure 4 , 7A View Figure 7 ); ventrally, surface of genital-double somite transversely striated distally ( Figures 4F View Figure 4 , 7B View Figure 7 ). Dorsal surface of genital-double somite striated with a right, pronounced wrinkle ( Figure 4G View Figure 4 ). Anal somite subequal in length to preanal somite. Furcal rami hairy on medial and lateral margins; the four terminal, lateral and dorsal setae are subequal in length ( Figure 4G View Figure 4 ), and all seta are biserially plumose.

Antennule. Twenty-five-segmented ( Figure 4H View Figure 4 ), tip reaching genital somite; armament per segment as follows: 1s+1ae; 3s+1ae; 1s+1ae; 1s; 1s+1ae; 1s; 1s+1ae; 1s+1sp; 2s+1ae; 1s; 2s; 1s+1sp+1ae; 1s; 1s+1ae; 1s; 1s+1ae; 1s; 1s; 1s+1ae; 1s; 1s; 1s+1ae; 1s+1ae; 2s; 3s+1ae.

Antenna. Coxa with one long seta. Long basis with two subequal setae on inner, distal margin. Two-segmented Enp, proximal segment with two setae and one row of spines; Enp2 with two lobes: outer lobe with tiny spines plus four distal and two lateral setae; inner lobe with eight setae. Seven-segmented Exp; setation pattern on each segment as follows: 1, 3, 1, 1, 1, 1, 4 ( Figure 5A View Figure 5 ).

Mandible with six rounded teeth on gnathobase, a movable tooth at the tip, and a rounded lateral projection ( Figure 5B View Figure 5 ). Coxa nude, basis with four setae. Bi-segmented Enp; Enp1 with four setae; Enp2 quadrangular, with tiny spines and eight distal, long setae. Four-segmented Exp, with 1, 1, 1, 3 setation pattern.

Maxillule. Praecoxal arthrite with 13 spiniform setae, nine anterior and four posterior; coxal epipodite bearing nine long setae, inner two smaller and thinner than the others; coxal endite quadrangular with four setae on distal margin. Basis with one internal lobe bearing four setae. Similar number of setae on basal endite; one-segmented Enp with nine setae. One-segmented Exp with seven setae ( Figure 5C View Figure 5 ).

Maxilla. Praecoxa with two lobes, first lobe with four terminal and two lateral setae; second lobe bearing three long setae and tiny basal spines. Coxa with two lobes, each one with three long setae, distal lobe with spines along medial surface ( Figure 5D View Figure 5 ). Two well-developed basal lobes; proximal lobe bearing four setae, distal lobe with one seta. Two-segmented Enp; Enp1 bearing one seta, Enp2 with four setae.

Maxilliped. Praecoxa and coxa fused forming a long segment ( Figure 5E View Figure 5 ). Coxa with three distinct lobes, first and second lobes each with three setae; third lobe with four setae plus two rows of long spine-like setae. Basis with a row of spine-like setae plus three short setae. Six-segmented Enp; Enp1 partially fused to Enp2; setation pattern as 2, 3, 2, 2, 2, 4.

Thoracic limbs. P1 with two-segmented Enp, and three-segmented Exp, coxa and basis with spine-like setae on lateral margins ( Figure 5F View Figure 5 ). P2 to P4 with threesegmented Enps and Exps ( Figure 5G–I View Figure 5 ), setation and spine formulae of each element of the thoracic limbs as in Table 2. Terminal exopodal spines of each P1–P4 with curved tips, armed with spines and hair-like setae ( Figure 5F–I View Figure 5 ).

Fifth leg. Coxa with one large sensilla on posterior view, basis with a delicate lateral seta ( Figure 5J View Figure 5 ). Three-segmented Exp: Exp1 cylindrical, Exp2 is a biserially armed claw, and Exp3 distinct, bearing a long seta and a short spine ( Figure 5J View Figure 5 ). Bisegmented Enp as long as Exp1, terminal Enp segment with two long setae plus one oblique row of hair-like setae, proximal segment nude ( Figure 5J View Figure 5 ).

Male. Total body length 960.9 ± 27.73 µm on average, range 910–1000 µm, n = 15. Slender body, cephalosome is the widest prosomal region in dorsal view. Suture between fourth and fifth pediger dorsally incomplete ( Figure 6A View Figure 6 ). As in female, the body is arched downwards in lateral view ( Figure 6B View Figure 6 ). Long rostral points, the left is slightly shorter than the right, which is bearing a lateral, basal hump ( Figure 6C View Figure 6 ). Left antennule as in female. Left thoracic wing not projected, bearing one spine ( Figure 6D View Figure 6 ); right thoracic wing projected, with one large ventral spine, plus one thin dorsal seta (arrowed in Figure 6E View Figure 6 ).

Right side of first urosomal segment with one spine ( Figure 6E View Figure 6 ). Five-segmented urosome; rows of tiny spines on dorsal surface of second to fourth urosomal segments ( Figure 6F View Figure 6 ); asymmetrical preanal segment, longer and bulbose in right side. Furcal rami hairy on medial margin.

Right antennule. Twenty-two-segmented; armament per segment as follows: 1s+1ae; 2s+2ae; 1s+1ae; 1s; 1s+1ae; 1s; 1s+1ae; 1s+1sp; 2s+1ae; 1s+1sps; 1s+1sps; 1s+1ae+1sp; 1s+1ae+1sps; 2s+1ae+1sps; 2s+1ae+1sps; 2s+1ae+1sps; 1s; 1s; 1s+2ae; 4s; 2s; 4s+1ae ( Figure 6G View Figure 6 ). Antepenultimate segment with a fang-like projection, less than half the length of penultimate antennular segment, and grooves on inner surface ( Figure 7C View Figure 7 ). Segments 13–16 wider. Spiniform process on segment 10 shorter than the bearing segment, reaching the base of the stout spine of the next segment. Spiniform process on segment 11, 2.1 times longer than spiniform process on segment 10. Segments 8 and 12 with one short spine. Parallel spiniform processes on segments 13 and 14. Base of stout spine on segment 13, thinner than the length of the bearing segment. Short spiniform processes on segment 15 and 16 ( Figure 6H View Figure 6 ). Mouth parts, and P1–P4 as in females.

Fifth leg, caudal side. Long distal sensillae on both, left and right coxae ( Figure 6I View Figure 6 ). Right basis with two projections on inner side: one medial semi-elliptical lamella, and one triangular, basal process, plus one fold along medial axis ( Figures 6I View Figure 6 , 7D View Figure 7 ). Right Enp twice as long as Exp1, which bears a chitinous membrane at its posterior edge. Exp2 1.8–1.9 times longer than wide with two curved, short hyaline membranes; aculeus inserted at distal third of the posterior side of the segment. Exp2 is 1.65–1.74 times longer than aculeus; which is armed with spines on medial edge ( Figure 7E View Figure 7 ) and with a curved, sharp tip; terminal claw very long, bent, with looped sharp tip ( Figure 7F View Figure 7 ). Right Enp unsegmented bearing two long setae and one oblique row of tiny spines. Left leg with quadrangular basis and bi-segmented Enp. Left Enp with two spines plus one row of setae on its tip ( Figure 6I View Figure 6 ). Bi-segmented Exp; Exp1 is

2.0–2.1 times longer than Exp2; which bears a lateral spiniform seta. Exp2 tapering distally and with two or three short chitinous denticles ( Figure 6I View Figure 6 ).

Etymology

The species is named after Eduardo Suárez-Morales, in recognition for his extensive contribution to the knowledge of the marine and freshwater copepods of Mexico and the world.

Remarks

The specimens examined here, were included under the genus Mastigodiaptomus Light, 1939   because of the possession of the following morphological features (1) segment 11 of both female antennules and left male antennule with two setae; (2) coxa of female P5 with a long, spatulated sensilla; (3) one lateral spine on Exp1P 1 in both sexes; (4) Enp of right male P5 longer than right Exp1; (5) right male antennule with spiniform process on segments 10, 11 and 13–16; (6) basis of right male P5 with hyaline lamellae on caudal side.

Mastigodiaptomus suarezmoralesi   sp. nov. does not match any species in the key by Wilson and Yeatman (1959) or in the key by Suárez-Morales and Elías- Gutiérrez (2000). The new species can be distinguished from other known species of Mastigodiaptomus   by the combination of several unique characters such as the wrinkled and striated genital-double somite in females, or the tiny spines on the dorsal surface of urosomal somites in males. The ornamentation of the right basis and Exp2, and the looped tips of the aculeus and terminal claw of the fifth leg in males, or the curved tips in terminal spines of all P1–P4, and the long rostral points in females and males are also relevant diagnostic characters in the new species.

Other morphological differences were found when M. suarezmoralesi   sp. nov. was compared with the eight known Mastigodiaptomus species   , especially in the female urosome and male fifth leg. The morphological comparison is on Table 3.

The dorsal process on the last thoracic segment was absent in all the adult females surveyed here; this character has been recorded as variable in or between populations of M. amatitlanensis ( Wilson and Yeatman 1959)   ; M. texensis ( Wilson 1953)   ; M. albuquerquensis ( Bowman 1986)   ; and M. montezumae ( Santos-Silva et al. 1996)   . Mastigodiaptomus reidae   is another species without this process ( Suárez-Morales and Elías-Gutiérrez 2000). According to Wilson and Yeatman (1959), in M. purpureus   the dorsal projection on the fifth female pediger is always present.