Nymphon timons, Sabroux & Hassanin & Corbari, 2022

Sabroux, Romain, Hassanin, Alexandre & Corbari, Laure, 2022, Sea spiders (Arthropoda: Pycnogonida) collected during the Madibenthos Expedition from Martinique shallow waters, European Journal of Taxonomy 851 (1), pp. 1-141 : 66-69

Nymphon timons sp. nov.

urn:lsid:zoobank.org:act:86C9C63A-9B7A-4D45-ABAD-39D6DBA6CFD9

Figs 15–16

Nymphon sp. 2 – Sabroux et al. 2019b: tab. 1, fig. 3.

Material examined

Holotype MARTINIQUE • ♀; Pointe du Diamant; 14°27ʹ N, 61°04.1ʹ W; depth 70 m; 9 Sep. 2016; st. AD214; MNHN-IU-2016-844/ MK411158 .

Paratypes MARTINIQUE • 1 ♀; Pointe du Diamant; same collection data as for holotype; MNHN-IU-2016-887/ MK411196 • 1 ♂, 1 ♀; same collection data as for holotype; MNHN-IU-2016-569 • 1 ♂; E of Le Vauclin ; 14°34.2ʹ N, 60°44.8ʹ W; depth 90 m; 14 Sep. 2016; st. AD231; MNHN-IU-2016-1201 • 1 ♂; same collection data as for preceding; MNHN-IU-2021-6623 .

Etymology

Noun in apposition. Named after the Ti Mons (from Martinique Creole: ‘little monster’), a malevolent creature of Martinique folklore which is given birth by placing an egg under his master’s armpit during Lent.

Description (holotype, ♀, MNHN-IU-2016-844)

BODY. Small species. Trunk completely segmented; cuticle smooth. No dorsomedian ornamentation. Ocular tubercle rounded, about as tall as wide, with 2 small lateral sense organs; four pigmented eyes. Preocular neck broad, medium-sized, about as long as wide. Chelifore insertions well separated. Oviger base touching 1 st lateral processes. Lateral processes well separated by slightly less than their own diameter; 1 st, 2 nd and 3 rd lateral processes about 1.5 times as long as wide, 4 th about as long as wide; unornamented.

PROBOScIS. Large, cylindrical, rounded at tip.

ABDOMEN. Long, reaching beyond 1 st coxa, oriented diagonally. No basal articulation.

CHELIFORE. 2-articled, slender, reaching beyond proboscis. Scape 1-articled, with scarce setae, less than 3 times as long as wide. Chela carrying setae; palm slender, about as long as fingers. Fingers slender,

subequal in length, with 17 denticled teeth on immovable finger and 15 on movable finger. Some teeth of movable finger curved.

PALP. 5-articled. 1 st article shortest, less than twice as long as wide. 2 nd article longest, 7.5 times as long as wide. 3 rd article 0.8 times as long as 2 nd, with one ventral seta near distal margin. 4 th article 0.4 times as long as 3 rd, with one ventral seta near distal margin. 5 th article about ¼ longer than 4 th, with distal setae. 4 th and 5 th palp articles together about as long as 3 rd.

OvIGER. 10-articled, with scarce setae. 1 st article shortest, shorter than wide. 2 nd and 3 rd articles subequal in length. 4 th article 3 times as long as 2 nd. 5 th article slightly longer than 4 th. 6 th article half as long as 5 th. 7 th article longer than 8 th, 9 th or 10 th, less than 3 times as long as wide. 8 th, 9 th and 10 th articles subequal, about twice as long as wide. Strigilis spines compound, with 2 pairs of long basal teeth, then 3 long teeth at end of long elongation; strigilis formula 5:4:4:4. Terminal claw as long as 10 th article, pectinated with 5 long lateral teeth.

LEGS. Slender, with scarce setae. Coxa 1 about 1.5 times as long as wide, carrying setae on distal margin. Coxa 2 longer than coxae 1 and 3 together, widening distally. Coxa 3 about as long as wide, with ventral setae carried distally. Femur about 6.5 times as long as distal width, inflated by ovaries in holotype specimen. Tibia 1 subequal to femur in length, about 12.5 times as long as wide, with one long spine about half its size. Tibia 2 longest, about 1.5 times as long as femur or tibia 1, carrying rows of setae on ventral, dorsal and lateral sides, and 2 ventral spines on distal margin. Tarsus rather long. Propodus less than twice as long as tarsus and ¼ times as long as tibia 2, slightly curved, carrying setae; heel spines absent, 4 sole spines. Main claw less than half as long as propodus, curved. Auxiliary claws curved, about 0.8 times as long as main claw.

MEASUREMENTS (mm). Trunk 0.94; abdomen 0.27; proboscis 0.30; chelifore scape 0.31; chela palm 0.31; chela finger 0.29; coxa 1 0.13; coxa 2 0.35; coxa 3 0.13; femur 0.68; tibia 1 0.63; tibia 2 1.01; tarsus 0.15; propodus 0.26; main claw 0.12; auxillary claw 0.09.

Sexual dimorphism

Male femur narrower, not swollen. Cement glands and cement gland pores inconspicuous, no cement gland tube. Oviger articles longer: in specimen MNHN-IU-2021-6623, 3 rd article longer than wide, 4 th article about 4 times as long as 2 nd article, 5 th article about 1.1 times as long as 4 th. 5 th oviger article curved, with distal apophysis.

Individual variability

Number of teeth on chelifore fingers 13 to 17 in investigated specimens. Strigilis formula slightly variable although always low, 2 to 5 spines per strigilis article, highest number on 1 st strigilis article. Number of teeth of oviger terminal claw variable, 4 to 5 in investigated specimens.

Remarks

Nymphon timons sp. nov. is the only species of Nymphon in the Madibenthos material that does not belong to the aequidigitatum group. It is a small species for the genus, and is differentiated from other species of Nymphon by the combination of the following characters: tarsus about half as long as propodus; auxiliary claws about 0.8 times as long as main claw; preocular neck medium, about as long as wide; lateral processes separated by slightly less than their own diameter; tibia 2 about 1.5 times as long as tibia 1 or femur; chela teeth denticled; oviger terminal claw pectinated; oviger base touching first lateral processes; fourth and fifth palp articles together about as long as third palp article.

To some extent, Nymphon timons sp. nov. shares similarities with N. boogoora Bamber, 2008 from Eastern Australia: both species share the pectinated oviger terminal claw, the long tibiae 2, and the same palp structure ( Bamber 2008). However, N. boogoora does not have the chela teeth denticled, and its abdomen does not extand beyond the 4 th lateral processes. Nymphon timons was only collected at two locations: one on the Atlantic coast and the other on the Caribbean coast.

Distribution

Only known from Martinique.

Depth range

70– 90 m.

Figures

Fig. 15. Nymphon timons sp. nov., holotype, ♀, MNHN-IU-2016-844. A. Body, dorsal view. B. Body, lateral view (same scale as A). C. Fourth leg. D. Tarsus and propodus of fourth leg. E. Chela. F. Palp. G. Oviger. H. Oviger strigilis. I. Compound denticle and terminal claw of strigilis.

Fig. 16. Nymphon timons sp. nov., paratype, ♂, MNHN-IU-2021-6623. Oviger.