Lipogramma barrettorum Baldwin, Nonaka & Robertson

Baldwin, Carole C., Tornabene, Luke, Robertson, D. Ross, Nonaka, Ai & Gilmore, R. Grant, 2018, More new deep-reef basslets (Teleostei, Grammatidae, Lipogramma), with updates on the eco-evolutionary relationships within the genus, ZooKeys 729, pp. 129-161 : 131-135

Lipogramma barrettorum Baldwin, Nonaka & Robertson sp. n. English: Blue-Spotted Basslet; Spanish: Cabrilleta manchado azul Figures 1, 2, 3

Type locality.

Curaçao, southern Caribbean.

Holotype.

USNM 440439, 26.5 mm SL, tissue no. CUR16008, GenBank accession no. MG676227, Curasub submersible, sta. CURASUB16-33, Curaçao, west of Substation Curaçao downline, 12.083197 N, 68.899058 W, 161 m depth, 7 October 2016, C. Baldwin, B. Van Bebber, D. Pitassy & T. Devine.

Paratypes.

USNM 406392, 24.5 mm SL, tissue no. CUR11392, Curasub submersible, sta. CURASUB11-06, Curaçao, off Substation Curaçao, 12.083197 N, 68.899058 W, 132-141 m depth, 31 May 2011, C. Baldwin, B. Van Bebber, A. Schrier & A. Driskell; UF 239254, 28.0 mm SL, tissue no. CUR11426, collection information same as USNM 406392; USNM 414914, 13.0 mm SL, tissue no. CUR12149, Curasub submersible, sta. CURASUB12-15, Curaçao, off Substation Curaçao, 12.083197 N, 68.899058 W, 123-160 m depth, 10 August 2012, C. Baldwin, B. Brandt, A. Schrier & P. Mace; USNM 431687, 25.2 mm SL, tissue no. CUR14079, Curasub submersible, sta. CURASUB-MISC14, Curaçao, off Substation Curaçao, 12.083197 N, 68.899058 W, no depth data, September 2014, Substation Curaçao staff; USNM 436460, 27.0 mm SL, Tissue no. CUR15125, Curasub submersible, sta. CURASUB15-21, Curaçao, off Substation Curaçao, 12.083197 N, 68.899058 W, 90-249 m depth (no discrete depth observation), 22 September 2015, C. Baldwin, B. Brandt & E. Duffy; USNM 436474, 10.2 mm SL, tissue no. CUR15139, Curasub submersible, sta. CURASUB15-27, Curaçao, Playa Forti, 12.368 N, 69.155 W, 50-246 m (no discrete depth observation), 29 September 2015, A. Collins, B. Brandt, A. Schrier & T. Devine.

Diagnosis.

A species of Lipogramma distinguishable from congeners by the following combination of characters: pectoral-fin rays 15-16 (modally 16); gill rakers 12-14 (modally 12, 8-10 rakers on lower limb); four supraorbital pores present along dorsal margin of orbit, a pore present between one above mid orbit and one above posterodorsal corner of orbit; caudal fin rounded; body mostly yellow in life with 11 or 12 narrow brownish bars on trunk; posterior base of soft dorsal fin with large white- or blue-rimmed black ocellus; dorsal, anal and caudal fins yellow with blue/grey (brown in preservative) wavy bars or square-shaped spots. Pelvic fins blue/grey with scattered yellow-ringed dark spots. The new species is further differentiated genetically from congeners for which molecular data are available in mitochondrial COI and nuclear Histone 3, Rhodopsin, TMO-4C4, and RAG1.

Description.

Counts and measurements of type specimens given in Table 1. Seven specimens examined, 10.2-28.0 mm SL. Dorsal-fin rays XII, 9 (last ray composite); anal-fin rays III, 8 (last ray composite); pectoral-fin rays 15-16, modally 16, 16 on both sides of holotype; pelvic-fin rays I,5; total caudal-fin rays 25 (13 + 12), principal rays 17 (9 + 8), spinous procurrent rays 6 (III + III), and 2 additional rays (i + i) between principal and procurrent rays that are neither spinous nor typically segmented; vertebrae 25 (10 + 15); pattern of supraneural bones, anterior dorsal-fin pterygiophores, and dorsal-fin spines 0/0/0+2/1+1/1/; ribs on vertebrae 3-10; epineural bones present on at least vertebrae 1-14 in holotype; gill rakers on first arch 12-14 (3-4 + 8-10), modally 12 (3+9 or 4+8), 12 (3+9) in holotype; upper-limb rakers and lowermost one or two rakers very small or present only as nubs, all other gill rakers elongate and slender with tooth-like secondary rakers as in L. evides Robins & Colins 1979 (Baldwin et al [2016: fig. 3]); pseudobranchial filaments ~4-7 (~5 in holotype), filaments fat and fluffy but poorly formed in most specimens; branchiostegals 6.

Spinous and soft dorsal fins confluent, several soft rays at rear of fin forming slightly elevated lobe that extends posteriorly beyond base of caudal fin. Pelvic fin, when depressed, extending posteriorly to point between base of second or third anal-fin spine and posterior base of anal fin, first pelvic-fin ray elongate. Dorsal profile from snout to origin of dorsal fin convex. Diameter of eye of holotype contained three times in head length. Pupil slightly tear shaped, with small aphakic space anteriorly. Scales extending anteriorly onto posterior portion of head, ending short of coronal pore. Scales present on cheeks, opercle, preopercle, interopercle, and isthmus. Scales lacking on top of head, snout, jaws, and branchiostegals. Scales large and deciduous, too many scales missing in most specimens to make accurate scale counts. In one paratype (USNM 436460) approximately 21 lateral scales between shoulder and base of caudal fin, approximately 4 scale rows on cheek, and approximately 9 scale rows across body above anal-fin origin. Scales on head and nape without cteni, scales on rest of body ctenoid. Fins naked.

Margins of bones of opercular series smooth, opercle without spines. Single row of teeth on premaxilla posteriorly, broadening to 2-3 rows anteriorly, teeth in innermost row smallest, some teeth in outer row enlarged into small canines. Dentary similar, holotype with 6 enlarged teeth in outer row near symphysis. Vomer with chevron-shaped patch of teeth. Palatine with long series of small teeth. Conspicuous pores present in infraorbital canal (2 pores), portion of supraorbital canal bordering dorsal portion of orbit (4), on top of head (1 median coronal pore), preopercle (at least 5), and lateral-line canal in the post-temporal region (3). The 4 supraorbital pores situated as illustrated by Baldwin et al. (2016: fig 4) for L. evides . Posterior nostril situated just ventral to anteriormost supraorbital pore, nostril a single large opening. Anterior nostril at apex of elongate narial tube and situated just posterior to upper lip. No lateral line present on body.

Coloration: In life or deceased but prior to preservation (Fig. 1): ground color of body brownish yellow, head darker than trunk, especially on underside. Head: dorsal midline of head with thin blue-white stripe beginning on lower lip, continuing on upper lip and over snout to nape; iris yellow, blue-white bars anterior and posterior to pupil; an indistinct yellow/brown bar from center of lower edge of iris to lower jaw, bar bordered anteriorly and posteriorly by smaller pale bars that extend up to top of eye. Trunk: 9-12 narrow dark bars between pectoral-fin base and caudal peduncle, bars about as wide as paler interspaces. Dorsal fin: yellow, with a thin blue-grey margin; series of straight, wavy, or irregular blue-grey bars on basal 2/3 of spinous dorsal fin; basal half of soft-dorsal with a large black ocellus complete ringed in blue-white pigment, ocellus extending onto trunk; distal half of fin with 2-3 rows blue-grey round- to square-shaped spots, these markings (here and on other unpaired fins) with pale centers and darker edges. Anal fin: yellow, with a thin blue-grey margin; 5-6 rows of blue-grey square-shaped spots between fin base and margin, some of which may fuse to form irregular lines. Caudal fin: yellow, with thin blue-grey posterior margin and 6-7 bars formed by vertical rows of blue-grey square-shaped spots on inter-radial membranes, basal two rows palest. Pectoral fins: translucent, base as dark as trunk bars. Pelvic fins: opposite color scheme to that of other fins, i.e., mostly blue-grey with yel low spots along inter-radial membranes; proximally, spots with tiny black center; distally, dark centers larger, some spots appearing completely dark. Juveniles: the 12- and 15-mm SL paratypes (Fig. 2) with similar pigment pattern as adults. Comment regarding live coloration: photographed against a light background (Fig. 1A, C), “blue-grey” in description above = grey; photographed against a black background (Fig. 1B), “blue-grey” = blue. Preserved coloration (Fig. 3A): Head mostly brown, trunk mostly tan with darker tan to brown bars. Yellow portions of median fins in life clear in preservative, blue-grey markings on fins in life dark brown to black in preservative.

Distribution.

Known only from specimens collected off Curaçao, southern Caribbean.

Habitat.

Lives in or immediately above elevated rocky habitat with ample cracks or holes into which the fish retreated upon approach of the submersible. The holotype was collected at 161 m, which is the only discrete depth recording for the species. Depth ranges for two specimens were recorded as 123-160 m and 132-141 m, thus providing a potential total depth range of 123-161 m. Depth ranges for two additional specimens of 90-249 m and 50-246 m reflect depths visited during an entire submersible dive and provide little information relevant to establishing this species’ depth distribution.

Etymology.

Named Lipogramma barrettorum in recognition of the support of Craig and Barbara Barrett for the Smithsonian’s Deep Reef Observation Project (DROP).

Common name.

We propose blue-spotted basslet in reference to the numerous blue/grey markings on the dorsal, anal, and caudal fins in life.

Genetic comparisons.

Table 2 shows average inter- and intraspecific divergences in COI among species of Lipogramma analyzed genetically in this study. Average intraspecific divergence among the seven specimens of L. barrettorum is 0.003 substitutions per site, and interspecific divergences between it and the other species for which data are available range from 9.9% ( L. evides ) to 25.3% ( L. klayi ).

Comments.

The holotype has two cysts, one at the base of the uppermost left pectoral-fin ray and one about mid-way along the length of the elongate first left pelvic-fin ray (Fig. 4). The cysts or galls are likely parasitic, but further analysis is needed. No other cysts were observed on the holotype or paratypes.