Pacific Science (1980), vol. 34, no. 4 c 1981 by The University Press of Hawaii. All rights reserved Contributions to the Knowledge of the Alpheid Shrimp of the Pacific Ocean Part XIX. On Alpheus randalli, a New Species of the Edwardsii Group Found Living in Association with a Gobiid Fish1 ALBERT H. BANNER and DORA M. BANNER2 ABSTRACT: A new species of snapping shrimp, Alpheus randalli, which was collected in association with a goby, Amblyeleotris sp., in the Marquesas is described. A shrimp of similar coloration and association was observed in the Indian Ocean. This species is the second of the Edwardsii group reported to live in association with gobies. Alpheus randalli sp. nov. acute tip reaching to end of first article. Scaphocerite with squamous portion narrow Figures 1-3 and reaching to middle of third antennular HOLOTYPE: BPBM S8572; 28-mm male from article; lateral tooth strong, curved and mark- Nuka Hiva, Marquesas Islands, northwest edly longer than squame. Carpocerite 4.6 side Sentinelle de Test, in sand and fine coral times as long as broad when viewed in- rubble at 18 m (60 ft). Collected by J. E. feriorly and as long as lateral tooth of sca- Randall, 7 May 1971. Commensal with phocerite. Basicerite with acute lateral tooth. orange-barred goby Amblyeleotris sp. (Note: The general proportions are similar (Specimen collected with a small multiprong to those found in the holotype, but in the Hawaiian spear; its impalement distorted the holotype the cephalic appendages are dis- anterior body region.) placed forward in relation to carapace. Contrast Figures 3a and m.) PARATYPE: 25-mm male at the same time Ratio of articles of third maxilliped: and location as holotype. (Specimen lacking 10:4:8. Inferior margins of all articles carry- small chela.) ing many long hairs; tip of third article DESCRIPTION: In paratype, rostrum acute, bearing a brush of long fine hairs. 1.5 times as long as broad at base, or- Large chela 2.4 times as long as broad bitorostral margin rather abrupt, not with fingers occupying the distal 0.3. Plunger broadly rounded nor indented; tip reaching of dactylus of only slight development and almost to end of first antennular article. fitting into shallow socket on pollex. Rostral carina strong and reaching to pos- Superior saddle shallow, proximal shoulder terior margin of orbital hoods. Second an- markedly overhanging floor of groove, distal tennular article 1.8 times the visible portion shoulder gradually rounded. Lateral palmar of first, 1.9 times as long as broad and more depression well defined, triangular, reaching than twice length of third. Stylocerite with proximally to linea impressa. Medial palmar depression slightly quadrangular, well de- fined, reaching to linea impressa near middle 1 Hawaii Institute of Marine Biology contribution of palm. Inferior shoulder heavy but round- number 599. This work was supported in part by ed, superior portion at right angle to axis of National Science Foundation grants GB-42498 and BMS-74-1184. Manuscript accepted 12 July 1980. chela. Medial face of merus 1.3 times as long 2 University of Hawaii, Hawaii Institute of Marine as broad distally, bearing five small spines Biology, Post Office Box 1346, Kaneohe, Hawaii, 96744. on its inferior margin and a strong tooth 401 402 PACIFIC SCIENCE, Volume 34, October 1980 distally. Superodistal margin bearing several overhanging the floor of the groove; (c) with long hairs. Small chela of male (small chela the merus of the third leg unarmed and with of female unknown) subbalaeniceps, 3.5 a simple dactylus. In this group, A. [species times as long as broad with fingers equal in novum] Banner and Banner (1981a) can be length to palm. Oppositional surface of dac- separated from A. randalli by the papillae tylus bearing a rounded ridge that fits into carried on the inferior lobe of the large chela excavate oppositional surface on pollex. and the inner face of the small chela of the Medial side of excavation forms a strong male; by the fingers of the small chela, which ridge, inner side of ridge bearing several run about 1.5 times the length of the palm; short stiff hairs. Superior surface of palm and by the second carpal article of the with broad shallow longitudinal groove ex- second leg, which is only 0.5 instead of 0.7 tending proximally to linea impressa. Carpus the length of the first. Alpheus bisincisus De cup-shaped, bearing on its medial face a Haan (1850) can best be separated from this slight distal notch; both the inferolateral and species by the rostrum, which is flat and inferomedial surfaces bearing slight incision- overhanging deep orbitorostral grooves. like depressions that continue proximally to Alpheus chiragricus Milne-Edwards (1837) is the articulation. Merus similar to that of characterized by the acute spiniform tips of large chela, 1.8 times as long as broad dis- the proximal shoulder both on the superior tally and bearing distally on its inferointernal saddle and on the lower shoulder on the margin five short heavy spines and an acute large chela. In A. edwardsii (Audouin, 1827) tooth. the inferior shoulder of the large chela ex- Ratio of carpal articles of second leg: tends forward of the associated groove on 10:7:4:4:5. the outer face, and the meri of both cheli- Ischium of third leg bearing heavy spine. peds lack movable spines. Alpheus pareu- Merus inermous, 4.8 times as long as broad; chirus Coutiere (1905) and A. p. imitatrix De carpus 0.5 as long as merus, inferior and Man (1909) again do not bear movable superior margins terminating in small round- spines on the meri of both chelipeds, and the ed projections; propodus 0.6 as long as small chela of the male of the first subspecies merus, bearing on its inferior margin 13 and of both sexes of the second subspecies spines placed in irregular pairs and a pair bears a definite superior saddle with as- distally, superior and inferior margin both sociated depressions of the medial and la- bearing long setae. Dactylus simple, 0.35 as teral faces instead of the ill-defined superior long as propodus. longitudinal depression. Telson 2.2 times as long as posterior The holotype is placed in the Bernice P. margin is wide, maximum width 1.35 times Bishop Museum, Honolulu, Hawaii (BPBM width of tip. Posterolateral spines small, S8572). The paratype is placed in the with inner pair slightly longer. Anterior pair Smithsonian Institution, Washington, D.C. of dorsal spines placed anterior to middle. DISCUSSION: The color of Alpheus randalli DIAGNOSIS: The form of the large chela is as follows (based upon several 55 x places this species firmly within the 55-mm transparencies by J. E. Randall of Edwardsii group of the genus Alpheus. Of the holotype, one of which is reproduced in the large number of species placed within the Figure 1): Base color of shrimp transparent group, only six species and subspecies have to white with broad red bands and spots. the following combination of characteristics Large cheliped with band at articulation of in common with this species [see key, di- fingers, a second band proximal to middle of chotomies from 52 to 84, Banner and Banner palm, both bands strong on medial surface, (198la)]: (a) males (and/or females) with a disappearing on lateral surface; with red balaeniceps or subbalaeniceps dactylus on patch at carpal articulation and red patch on the small chela; (b) with the proximal shoul- superior portion of merus. Small chela with der of the superior saddle of the large chela red band running from articulation of fin- 404 PACIFIC SCIENCE. Volume 34. October 1980 gers almost to carpal articulation; carpus ation with Amblyeleotris aurora (Polunin white, merus bearing broad red band dis- and Lubbock 1977:84) at North Male Atoll. tally. Antennular and antennal bases and Maldive Islands (Figure 2), at 36 m, and third maxillipeds white. Bar of red color with Stonogobiops dracula Polunin and anterior to cardiac groove. Distal portions of Lubbock (1977:74) at Mahe, Seychelles, at thoracic appendages yellow to yellow-green. 20 m. He reports that A. aurora carries Posterior end of carapace and tergum of first strong transverse bars of salmon pink; that and second abdominal segment with small Amblyeleotris sp. from the Marquesas have red patches. Two white patches on first and similar bands, but their color is more muted; second pleura, with small red patches pos- and that S. dracula has a white ground color terior to white patches. Tergum and pleura with near-vertical chocolate-brown bars, of third thoracic somite almost solid red. each white interspace bissected by a narrow Tergum and pleura of fourth abdominal seg- red vertical line; all three gobies live from ment with more narrow red bar. Red saddle about 10 to at least 35 m in depth. The two on posterior portion of sixth tergum. Distal named species of gobies have been reported three-quarters of uropods and half of telson only from the central Indian Ocean with final red bar. We know of no other (Maldives, Seychelles, Aldabra, etc.), while species of the Edwardsii group, or in the the unnamed species is known only from its group of species associated with gobies, that type locality. On the basis of gobiid shrimp have this color pattern (Banner and Banner relationship and of color, we are presuming 1981a, 19816, passim). that the specimens observed but not col- As indicated above, this species was col- lected from the Indian Ocean are the same lected by John E. Randall of the Bernice P. species as those that in the Marquesas.