Lotilia graciliosa Klausewitz, 1960

Shibukawa, Koichi, Suzuki, Toshiyuki & Senou, Hiroshi, 2012, Review of the shrimp-associated goby genus Lotilia (Actinopterygii: Perciformes: Gobiidae), with description of a new species from the West Pacific, Zootaxa 3362, pp. 54-64 : 61-62

Lotilia graciliosa Klausewitz, 1960

( Figures 1 B & 2C–D, Table 1)

Lotilia graciliosa Klausewitz 1960: 158 , figs. 8–10 (type locality: Sarad-Sarso Island, Farasan Islands, Red Sea); Goren 1979:44 –45.

Materials examined. Total 5 specimens, 15.2–31.3 mm SL: SMF 4794, 1 specimen (female, holotype of Lotilia graciliosa ), 29.3 mm SL, Sarad-Sarso Island, Farasan Islands, Red Sea; SMF 9581, 3 specimens (male, female and juvenile), 15.2–31.3 mm SL, Suakin, west coast of Red Sea; SMF 13299, 1 specimen (male), 29.9 mm SL, Elat, northern Red Sea, 1974.

Images examined (registered in the Image Database of Fishes of KPM). KPM-NR 61513, off southernmost part of Sinai Peninsula, Egypt, 30 Dec. 1991.

Diagnosis. See diagnosis of only congener, Lotilia klausewitzi .

Description. Dorsal-fin rays VI-I, 10* (5); anal-fin rays I, 9* (5); pectoral-fin rays 15 (1), 16* (6) or 17 (2); pelvic-fin rays I, 5* (10); segmented caudal-fin rays 9+8 (3), including 7+7 (3) branched rays; upper unsegmented caudal-fin rays 6 (2); lower unsegmented caudal-fin rays 5 (1) or 6 (1); longitudinal scales 50 (1), 51 (3) or 52 (2); transverse scales from origin of anal fin upward and forward to base of first dorsal fin 20 (2), 21 (2) or 22 (2); transverse scales from origin of anal fin upward and backward to base of second dorsal fin 17 (2), 18 (2) or 19 (2); transverse scales from origin of second dorsal fin downward and backward to base of anal fin 17 (2) or 18 (4); predorsal scales 0; scales in preventral midline 2 (1), 3 (1) or 5 (1); circumpeduncular scales 20 (2) or 22 (1); gill rakers 3+11 (1); pseudobranchial filaments 6 (1); vertebrae 10+16=26 (4); P-V 3/II II I I 0/9 (4); anal-fin pterygiophores anterior to first haemal spine 2 (4); epural 1 (4).

Coloration. According to Klausewitz (1960), coloration of the holotype when alive was as follows: ground color of head and body blackish-brown; snout and narrow area of maxilla pale gray; nape whitish; white spots on back and caudal peduncle; first dorsal fin with orange-colored ocellated spot; pectoral fin whitish, with black crossbars; caudal fin whitish basally, remaining part colorless and hyaline; other fins blackish-brown, likewise body; iris orange. Coloration of preserved specimens in alcohol is as follows: ground color of head and body dark grayishbrown; broad mid-dorsal pale beige stripe, extending from snout tip to bases of third or fourth spine of first dorsal fin through dorsal part of eye; two small pale beige saddles at anterior part of second dorsal-fin base and caudal peduncle; anterior nare tube pale; anteroventral part of first dorsal fin whitish; remaining part of first dorsal fin dark grayish-brown, gradually becoming paler distally; a conspicuous black spot with narrow pale margin (= ocellus), larger than eye, at center of first dorsal fin behind third spine; second dorsal fin dark grayish brown, gradually becoming paler distally, with a whitish anteroventral corner; anal fin dark grayish brown, with a small whitish blotch anteriorly; caudal fin subtranslucent, exclusive of basal scaled area dark grayish brown; pectoral fin subtranslucent, exclusive of triangular basal blackish area; several pupil- or eye-sized black spots at middle and submarginal parts of pectoral fin (those at middle of fin always larger); pelvic fin largely dark grayish-brown; pelvic frenum pale with a triangular or rounded blackish blotch basally.

Distribution and habitat. All examined specimens and underwater photographs of Lotilia graciliosa were taken from the Red Sea (see also “Distribution and habitat” of L. klausewitzi ). We could not detect any certain records of this species from other areas. There are records of “ Lotilia graciliosa ” from the Gulf of Aden ( Manilo & Bogorodsky 2003) and the Glorieuses Islands of western Indian Ocean ( Durville et al. 2003); unfortunately these records were not accompanied by any morphological information about the voucher specimen(s), and, thus, it was uncertain whether their identification was reliable.

According to Klausewitz (1960), this species is found only on sandy areas, and symbiotically associates with a snapping shrimp, probably Alpheus djiboutensis . It swims freely at ca. 10–15 cm above the nest hole as it moves its pectoral fins alternately. Karplus et al. (1974) reported that, in the northern Red Sea, L. graciliosa associated with an unidentified species of Alpheus (as Alpheus sp. A), not corresponding with A. djiboutensis .

Figures

FIGURE 1. Ventral (top), lateral (middle) and dorsal (bottom) views of heads of two species of Lotilia, showing cephalic sensory-canal pores (indicated by uppercase letters, except for AN and PN, which are defined below) and sensory papillae (indicated by lowercase letters). A) L. klausewitzi sp. nov., one of URM-P 3296, 21.5 mm SL, female; B) L. graciliosa, one of SMF 9581, 30.5 mm SL, male. AN and PN, anterior and posterior nares, respectively. Arrows show the position where the gill membrane is attached to isthmus. Drawn by K. Shibukawa.