Baseodiscus giribeti, Kajihara & Abukawa & Chernyshev, 2022

Kajihara, Hiroshi, Abukawa, Shushi & Chernyshev, Alexei V., 2022, Exploring the basal topology of the heteronemertean tree of life: establishment of a new family, along with turbotaxonomy of Valenciniidae (Nemertea: Pilidiophora: Heteronemertea), Zoological Journal of the Linnean Society 196, pp. 503-548 : 527

BASEODISCUS GIRIBETI SP. NOV.

( FIG. 2M )

Baseodiscus sp. DNA105588: Andrade et al., 2012: 157 (Bocas del Toro, Panama).

Baseodiscus unicolor: Kvist et al., 2014: 291 (in part) (Bocas del Toro, Panama).

Zoobank registration: u r n: l s i d: z o o b a n k. o r g: a c t: A 1 7 D 4 3 F D - E F D E - 4 7 D A - B 4 1 C - 9CE5B4871DDB.

Material examined: Photographs of type material, taken by G. Giribet. Holotype, MCZ IZ-135324 ( MCZ DNA105588 ), 30 March 2006, Isla Solarte (09 °18′ 36.6″N, 82 °13′ 01 ″W), Bocas del Toro Archipelago, Panama, collected by G. Giribet.

Sequences: From the holotype: JF293046 , 18S (1772 bp) ; HQ856866 , 28S (1863 bp) ; JF277749 , H3 (326 bp) ; JF277569 , 16S (449 bp) ; HQ848589 , COI (657 bp). Determined by Andrade et al. (2012) and deposited in GenBank as Baseodiscus sp. 2 SA-2011 .

Etymology: The specific name is dedicated to the collector of the type material, Prof. Gonzalo Giribet (Harvard University), for his remarkable contribution to the systematics of not only nemerteans but also Metazoa in general.

Description: Body uniformly pale brown in colour, without any distinctive colour pattern ( Fig. 2M ).

Distribution: So far detected only on the Caribbean coast of Panama (present study).

Remarks: In our ML tree ( Fig. 1 ), Baseodiscus giribeti was most closely related to B. unicolor . They differed by 5.6% in uncorrected P -distance for 16S ( KF 935452 , KF935459 , JF277569 vs. KF935451 , EF 124865 ) and 9.0% for COI ( HQ 848589 vs. KF 935505 ) [ KF935452 and JF277569 are from the same specimen, IZ- 135324 ( MCZ DNA105588)].

Figures

Figure 1. Maximum-likelihood (ML) tree showing the phylogenetic relationships among 41 newly sequenced specimens of pilidiophorans (indicated with solid blue circles). Numbers near nodes are support values, ML bootstrap/Bayesian inference (BI) posterior probability. Nodes with yellow triangles are fully supported, with 100% ML bootstrap and 1.00 BI posterior probability. New species names are indicated in bold. Some nodes were polytomous in the BI tree (indicated by hyphens in place of posterior probability values).

Figure 2. A, Eopilidion misakiense gen. et sp. nov., holotype, ICHUM 6303, lateral view, head to the right; B, Oxypolella hiebertae sp. nov., holotype, MIMB 42256; C, Cephalomastax brevis Iwata, 1957, ICHUM 6304; D, E, Valencinura jambio sp. nov., holotype, ICHUM 6305, anterior body fragment (D) and enlargement of intestinal region (E) showing yellowish proboscis (indicated by arrowheads); F, Baseodiscus takakurai Gibson, 1995, ICHUM 6306; G, Baseodiscus profundus sp. nov., holotype, MIMB 42257; H, I, Baseodiscus narusei sp. nov., holotype, ICHUM 6310, anterior end of body, dorsal (H) and ventral (I) views; J, Baseodiscus paracelensis sp. nov., holotype, MIMB 33132; K, Baseodiscus komatsui sp. nov., holotype, NMNS-Ne 1; L, Baseodiscus unicolor Stiasny-Wijnhoff, 1925; M, Baseodiscus giribeti sp. nov., holotype, MCZ IZ-135324; N, Baseodiscus cf. amboinensis (Staub, 1900); O, Baseodiscus hemprichii (Ehrenberg, 1828-1831), specimen from Okinawa, different from any voucher specimens in this study; P, Baseodiscus zebra sp. nov., holotype, RUMF-ZN-00001; Q, Baseodiscus quinquelineatus (Quoy & Gaimard, 1833), ICHUM 6319. Photographs by H. Kajihara (A, C, D, E, F, O), A.V. Chernyshev (B, G, J), T. Naruse (H, I), H. Komatsu (K), G. Giribet (L, M), D. Uyeno (P), and R.Yoshida (Q).