Questa manuelgerardi Núñez & Martínez 2023, n. sp.
Creators: name: Núñez, Jorge
name: Martínez, Alejandro
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Orbiniida
Orbiniidae
Questa
Questa manuelgerardi

description: Questa manuelgerardi n. sp.
Figures 1, 2
Questa sp. Martínez et al. 2021: 133.
Type Material. Azores, S „o Miguel. - Holotype (male) TFMCBM-AN/249, station 13 AZSM Porto da Caloura, 37º42.76’N 25º29.71’W, 17 m, fine volcanic sand, 22-07-2001, coll. J. Núñez; Paratypes: TFMCBM-AN/255, 50 specimens, same locality, date, coll. J. Núñez; TFMCBM-AN/253, 12 specimens, station 18 AZSM, Ilhéu de Vila Franca, 37º42.42’N 25º26.54’W, sandy substrate, 15 m, 26-07-2001, coll. J. Núñez, Pico. - Paratypes: TFMCBMAN/256, 4 specimens, station 11 AZP, Ilhéus da Madalena, 38º32.13’N 25º26.54’W, median sand patch, 26 m, 18- 07-2001, coll. R. Herrera.
Other material examined. S„o Miguel. SEM preparation on stub, DBAULL STUB 1, station 13 AZSM Porto da Caloura, 37º42.76’N 25º29.71’W, 2 female and 2 male, fine volcanic sand, 22-07-2001, 17 m, coll. J. Núñez, DBAULL station 14 AZSM, Faial da Terra, 37º44.21’N 25º11.46’W, 2 specimens, gravel patch on rocky substrate, 6 m, 23-07-2001; DBAULL station 17 AZSM, Ponta of Santa Iria, 37º50.14’N 25º28.99’W, 24 specimens, sandy substrate, 17 m, 25-07-2001; DBAULL station 22 AZSM, Ilhéu de Vila Franca, 37º42.42’N 25º26.54’W, 12 specimens, sandy substrate, 15 m, 26-07-2001. Pico.- DBAULL station 7 AZP, S„o Mateus, 38º25.50’N 28º27.41’W, 1 specimen, gravel, 22 m, 17-07-2001; DBAULL station 9 AZP, S„o Jo„o Sul, 38º24.49’N 28º20.02’W, 2 specimens, fine sand and gravel with freshwater seepages, 37 m, 17-07-2001. Faial.- DBAULL station 3AZF, Monte da Guia, 38º31.07’N 28º37.38’W, 3 specimens, shell gravel, 20 m, 15-07-2001, coll. J. Núñez.
Material examined for comparison. Questa trifurcata (Hobson, 1970), ZMUH, P-23408, 1 female; P-23407, 2 females; P-23409, 1 male and 2 females.
Description. Body elongate and threadlike, holotype length (fixed) 7.10 mm and 37 chaetigers, width in pre-genital region about 0.20–0.23 mm, and 0.15– 0.13 mm in post-genital region. Paratypes length (fixed) about 1.0–6.0 mm and about 28–37 chaetigers, width in pre-genital region 0.20–0.28 mm and 0.18– 0.12 mm post-genitally. Body segments cylindrical in cross–section; slightly marked intersegmental annulation in anterior and middle segments (Fig. 1A, C), decreasing posteriorly. Prostomium small, conical, narrow rounded tip, lacking appendages or eyes (Fig. 1A, B); nuchal organs paired slits on posterior lateral margins (Fig. 1A, B). Peristomium as wide as the following metastomial segments, without appendages and chaetae; ventrally forming anterior and posterior lips of mouth, followed by a buccal pad (Fig. 1A, B). Pre-genital region with the anterior chaetigers more compressed than the following, and in the post-genital region they progressively narrow towards the pygidium (Figs 1A; 2D). Branchiae absent. Parapodia biramous (Fig. 1A), composed of low mounds with noto- and neurochaetae (Fig. 1B), with two kinds of chaetae on all chaetigers; pinnate capillaries (Fig. 2A), and short bidentate hooks (Fig. 2B, C). Furcate chaetae absent. Capillary chaetae conspicuously pinnate (Fig. 2A), ranging from 1–4 in each bundle, reaching up to 5 in the anterior most chaetigers. Bidentate hooks with geniculate shafts, well developed main tooth with subdental ligament (Fig. 2B, C) and small upper accessory tooth (Fig. 2B, C), 1–2 per bundle. Pygidium bilobed by vertical incision, with two pairs of short dorsal and ventral cirri (Figs 1D; 2D), anal opening terminal.
Sexually dimorphic. Males have more segments than females, as well as smaller chaetae in chaetigers 12–13, with elevated cup-like or slit-like dorsal fold. Females have no reduction in the size of the chaetae, oocytes in the chaetigers 11–12.
Etymology. The species is dedicated to Manuel Gerardo Rodríguez, friend of the first author.
Distribution. Endemic of the Azores.
Remarks. The only species of the genus Questa that lacks branchial appendages are Q. trifurcata (Hobson, 1970) known only from the east coast of North America and Q. manuelgerardi n. sp., both species can be easily differentiated, since Q. trifurcata has furcate chaetae on the anterior chaetigers and lacks anal cirri on the pygidium, while Q. manuelgerardi n. sp. lacks furcate chaetae and has two pairs of anal cirri.
description: Published as part of Núñez, Jorge & Martínez, Alejandro, 2023, Two new species and records of the genus Questa (Annelida: Orbiniidae) from Azores and Canary Islands, Central Atlantic Ocean, pp. 403-412 in Zootaxa 5319 (3) on pages 405-407, DOI: 10.11646/zootaxa.5319.3.6, http://zenodo.org/record/8203012