202 

Fig. 13. Anisochromis straussi, USNM 216463, 22.8 mm SL, female, 
paratype, Saint Brandon’s Shoals. (Photograph by P. Hurst) 
of body; coloration of fins similar to when live; pale brown spots 
often present at base of each dorsal-fin ray; several pale brown spots 
sometimes present basally on anterior part of dorsal fin. Females 
(Fig. 13): pattern generally similar to live coloration, head and body 
becoming pale brown; pale markings on head and body indistinct or 
absent; dark spots and stripes on head mostly remain, becoming dark 
grey-brown to dark brown (ocellated spots sometimes absent, though 
possibly these represent intermediately coloured, sex-transforming 
specimens), sometimes with additional irregular brown spots and 
markings on cheek and operculum; dark barring on head and body 
variably remains, becoming brown to pale brown; dark punctate 
spots on caudal peduncle remain, becoming dark brown to dark 
grey-brown, sometimes extending anteriorly to near middle of 
dorsal- and anal-fin bases, ocassionally extending on to sides of 
body; dorsal and anal fins dusky brown to brownish hyaline, often 
with irregular pale brown small spots; barring on body sometimes 
extending slightly on to fin bases; caudal fin pale brown, remainder 
of fin pale brown to hyaline; pectoral-fin base pale brown, remain- 
der of fin pale brown to hyaline; pelvic fin dusky brown to brownish 
hyaline, paler on base and distal margin. 
HABITAT AND DISTRIBUTION 
Anisochromis straussi is known only from Saint Brandon’s Shoals 
(Fig. 6). According to Springer et al. (1977: 6), it was collected in 
0.25-11 m from rocky reefs that included dead and live coral, 
proximate to areas exposed at low tide. They further noted that 
‘specimens of A. straussi were lying on the bottom adjacent to 
isolated, small (perhaps less than 0.5 meter in diameter), live coral 
heads with surfaces composed of tiny finger-like projections. Our 
presumption is that the Anisochromis were living in the corals.’ 
COMPARISONS WITH OTHER SPECIES 
See under A. kenyae. 
REMARKS 
Springer et al. (1977) gave a standard length of 25.5 mm for the 
holotype of A. straussi, whereas we measured it as only 23.9 mm. 
MATERIAL EXAMINED 
Saint Brandon’s Shoals (= Cargados Carajos) Lagoon at Tortue 
Island (16°19'S 059°41'E), 0.15 m (stated depth 0.5 feet), V.G. 
Springer er al., 7 April 1976 (field number VGS 76-11), USNM 
216463, 19: 16.2-27.0 mm SL (paratypes); 2 miles east of Raphael 
Island (16°20'S 059°38.5'E), inside edge of reef flat, 0.15—1.05 m 
(stated depth 0.5-3.5 feet), V.G. Springer er al., 3 April 1976 (field 
number VGS 76-7), USNM 216462, 1: 23.9 mm SL (holotype), 
USNM 215859, 26: 18.7—26.1 mm SL (paratypes; x-radiographs 
only); off northern tip of Saint Brandon’s Shoals, ca. 16°25'S 
59°36'E, rocky reef with some live coral and some channels and 
white coarse sand bottom, 6—10.5 m (stated depth 20-35 feet), V.G. 
Springer et al., 6 April 1976 (field number VGS 76-10), BMNH 
A.C. GILL AND R. FRICKE 
1976.8.24.1-10, 10: 16.8-25.4 mm SL (paratypes; 21.5 mm SL 
paratype subsequently cleared and stained); about 100 yards off 
west side of Raphael Island (ca. 16°26'S 059°36'E), coral patch in 
surge channel, 0—7.5 m (stated depth 0-25 feet), V.G. Springer et al., 
2 April 1976 (field number VGS 76-6), USNM 216464, 1: 26.8 mm 
SL (paratype; x-radiograph only); lagoon south of Raphael Island 
(ca. 16°28'S 059°37'E), live and dead coral reef surrounded by fine 
white sand, 0—3.6 m (stated depth 0-12 feet), V.G. Springer et al., 8 
April 1976 (field number VGS 76-12), USNM 216466, 2: 26.5—28.3 
mm SL (paratypes; x-radiographs only); along southeast side of 
Grande Passe (ca. 16°28'S 059°40'E), face and channels of reef, 0— 
6 m (stated depth 0-20 feet), V.G. Springer et al., 5 April 1976 (field 
number VGS 76-9), CAS 37640, 14: 16.1-24.9 mm SL (paratypes; 
x-radiographs only); ca. 16°32'S 059°41'E, 0-2 m, V.G. Springer et 
al., 30 March 1976 (field number VGS 76-1), USNM 216465, 3: 
22.6-23.9 mm SL (paratypes; x-radiographs only); ca. 16°43'S 
059°35'E, live coral reef with dead rock and coral, rubble shore, 0- 
1.2 m (stated depth 0-4 feet), V.G. Springer ef al., 11 April 1976 
(field number VGS 76-17), AMNH 35892, 6: 22.0-28.0 mm SL 
(paratypes; x-radiographs only). 
KEY TO SPECIES OF ANISOCHROMIS 
la. Dorsal-fin rays 1,25—26, usually 1,25; anal-fin rays I,17—18, usually 
1,17; caudal vertebrae 22—24, usually 23; scales in lateral series 37-44, 
usually 38-41; anterior lateral-line scales 28-35, usually 30-34 (east 
Africa, Comoros Islands and Madagascar) ..............:.000 kenyae Smith 
Ib Dorsal-fin rays 1,25—27, usually 1,26; anal-fin rays I,17—19, usually 
1,18; caudal vertebrae 23-25, usually 24; scales in lateral series 40-45, 
usually 41—44; anterior lateral-line scales 32-39, usually 33-37 ...... 2 
2a Dorsal fin of male specimens pale in preservative, with conspicuous, 
large dark spot distally on anterior part of fin; pelvic fins of preserved 
males broadly pale on basal part of fin (sometimes slightly darker or 
dappled with darker spots on basalmost portion of fin) and abruptly dark 
distally, sometimes with pale distal margin; posterior interorbital pores 
3-4; total parietal pores 23-44, usually more than 30 (Réunion and 
IMVAUIEIGLUIS) 5. <cessccsccssceeseccenesestsstsesneesnecnuexcarctcesives mascarenensis Sp.nov. 
2b Dorsal fin of male specimens generally dusky in preservative, without 
large dark spot on anterior part of fin; pelvic fins of males mostly dusky 
in preservative, although sometimes with narrow pale basal area, with 
pale distal margin; posterior interorbital pores 1—2; total parietal pores 
14-30 (Saint Brandon’s Shoals)......: straussi Springer, Smith & Fraser 
ACKNOWLEDGEMENTS. We thank the following variously for assistance 
with radiography or photography or for the loan of specimens, radiographs or 
photographs: A. Bentley, O.A. Crimmen, S. Davidson, J.P. Garcia, P.C. 
Heemstra, A.-M. Hine, P. Hurst, S.L. Jewett, M. McGrouther, L. Palmer, J.E. 
Randall, S.J. Raredon, S.E. Reader, V.G. Springer, A. Suzumoto, T. Trnski 
and R. Winterbottom. The first author thanks the other members of the 1995 
Mauritius expedition for assistance in the field: P. Clark, B. Galil, P.C. 
Heemstra, W. Holleman, M.J. Smale and D.G. Smith. The success of the 
expedition also owes much to the kind assistance of D. Pelicier and of 
Mauritian Fisheries officials, particularly staff of the Albion Fisheries Research 
Centre. E. de Chavanes (Directeur, Directoire Régionale et Départementale 
des Affaires Maritimes, Saint-Denis, Réunion) granted a fish collecting and 
export permit to the second author. The second author is grateful to the 
German Research Council (DFG) for financial support of research trips to the 
Mascarenes in 1995 and 1998/1999. We thank V.G. Springer for helpful 
discussions and access to materials, and R.D. Mooi and R. Winterbottom for 
critically reviewing the manuscript and providing helpful suggestions. 
