PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 112(1):10^119. 1999.

Two new species of Aegla Leach (Crustacea: Decapoda: Anomura: Aeglidae) from southern

Carlos G. Jara and Victor L. Palacios

Institute de Zoologia "Dr. Ernst Kilian", Universidad Austral de Chile, Casilla 567, , Chile

Abstract. —Two new species of the genus Aegla Leach from southern Chile are described. Aegla cholchol, new species, a medium to large sized spinulated

aeglid, has the River Chol-Chol (Cautin Province) as its type locality. It is probably more related to A. rostrata, from subandean lakes at the Tolten and basins than to A. bahamondei, from the Tucapel River Basin on the western slope of the Nahuelbuta Coastal Cordillera. The other, A. hueicol- lensis, new species, a small to medium sized non- spinulated aeglid, has the River Pichihueicolla (Valdivia Province), on the western slope of the Pelada

Coastal Cordillera, as its type-locaUty. A. hueicollensis is similar to A. abtao

with which it shares more morphological attributes than with other non-spi-

nulated aeglids of the same geographic region (i.e., A. alacalufi, A. manni, and A. concepcionensis).

Continental Chile is a long and narrow Schmitt, 1942a, A. expansa Jara, 1992, A. strip of land extending from Arica to Cape pewenchae Jara, 1994, A. bahamondei Horn, characterized by a series of climatic Jara, 1982, A. spectabilis Jara, 1986, A. and biogeographical regions (see Di Castri rostrata Jara, 1977, A. abtao Schmitt, et al. 1968). Three main topographical fea- 1942a, A. d. denticulata Nicolet, 1845, A. tures, namely, the Andes Cordillera on the d. lacustris Jara, 1989, A. manni Jara, east, the Coastal Cordillera on the west, 1980, A. araucaniensis Jara, 1980, and A. and the Central Valley between both rang- alacalufi Jara & Lopez, 1981) have been es dominate the landscape from north to described for the area between Concepcion south (B orgel 1983). The central southern and Puerto Montt, several associated to the part of Chile, between the cities of Con- Coastal Cordillera. In fact, three, A. con- cepcidn (36°55'S) and Puerto Montt cepcionensis, A. bahamondei, and A. man-

(41°28'S), harbors the highest diversity of ni, are restricted to small basins on its aeglids and parastacids in the country (Ba- western slope. hamonde & Lopez 1963). This diversity In this paper two new species of Aegla, appears associated to the many rivers and both from localities in the Chilean Coastal lakes that constitute the drainage system of Cordillera between Concepcion and Puerto this area. Montt, are described. Aeglids are distributed along a stretch of Specimens are deposited in the Crusta- about 2000 kilometers, from the Choapa cean Collection of the Instituto de Zoologia, River (3r38'S) in the north down to Ma- Universidad Austral de Chile (IZUA C), dre de Dios Island (50°02'S) in the south Valdivia, Chile. The size of the specimens (Bahamonde & Lopez 1963, Jara & Lopez was recorded as carapace length (CL), i.e., 1981). At least ten species and two sub- distance between rostral apex and posterior species of Aegla (A. concepcionensis margin of cephalothorax. VOLUME 112, NUMBER 1 107

Fig. 1. Aegla cholchol, new species, male allotype, Chol-Chol River, IZUA C-328-B, dorsal view.

Aegla cholchol, new species LC), 6 males (14.9-27.2 mm LC), same

Figs. 1, 2a-i data as holotype. Other material. —3 females (21.5-23.5 Aegla bahamondei. —Jara, 1982:232 (in mm LC), Quepe River, 38°51'40"S, part), Fig. 1 (see Remarks). 72°37'02"W, C. A. Viviani coll., 24 Feb Type locality. —Chol-Chol River, 100 m 1969, IZUA C-008-B. 3 males (24.3-26.1 downriver from bridge in the town of Chol- mm LC), 2 females (23.8-25.6 mm LC), Chol, 38°36'40"S, 72°51'05"W, 29 km NW Quepe River at Boroa, 39°49'06"S, of Temuco, Province of Cautin, Chile. 72°53'02"W, C. G. Jara coll., 21 Dec 1982, Type material. —Holotype: female (24.5 IZUA C-297-B. 7 females (18.1-23.4 mm mm CL), C. G. Jara coll., 22 Dec 1982, LC), Traiguen River, 38°14'45"S, IZUA C-328-B. Allotype: male (22.4 mm 72°39'40"W, C. G. Jara & R. Navarro coll., CL). Paratypes: 9 females (17.5-30.3 mm 22 Dec 1982, IZUA C-316. 3 males (26.9- 108 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASfflNGTON

Fig. 2. Aegla cholchol, new species, male allotype, Chol-Chol River, IZUA C-328-B; a, anterior part of cephalothorax, dorsal view; b, anterior part of cephalothorax, lateral view; c, third and fourth sterna; d, second abdominal epimeron; e, telson plate; f, ischium of left cheliped, ventral view; g, carpus of left cheliped, ventral view; h, left cheliped, dorsal view; i, merus of cheliped, lateral view. Scales: d = 1 mm; a, b, c, e, f, g, i = 5 mm; h = 10 mm. VOLUME 112, NUMBER 1 109

18.9 mm LC), 5 females (26.4-15.5 mm lobe with prominent conical acute spine. LC), Colpi River near Galvarino, Middorsal carpal ridge tubercles blunt. 38°19'52"S, 72°47'10"W, C. G. Jara & R. Description. —Carapace slightly longer Navarro coll., 22 Dec 1982, IZUA C-317- than wide, somewhat setose especially on B. 2 males (19.3-29.3 mm LC), 6 females branchiostegal and pterygostomial areas. (23.6-26.0 mm LC), Quepe River, Abdominal terga and middorsal line of mer- 38°51'40"S, 72°37'02"W, C. G. Jara & R. us of second to fourth pereopods also se- Navarro coll., 21 Dec 1982, IZUA C-320- tose. Precervical portion narrower than A. 8 males (13.6-30.8 mm LC), 9 females postcervical; apex of acute pyramidal bran- (14.3-21.8 mm LC), Lumaco River at Lu- chial lobe separated from margin of third maco, 38°09'46"S, 72°54'21"W, C. G. Jara hepatic lobe by wide notch. Rostrum long, & R. Navarro coll., 22 Dec 1982, IZUA C- acute, narrow, styliform, slightly expanded 321. 5 males (15.8-25.5 mm LC), 9 females at its proximal %\h but conical and some- (17.3-24.1 mm LC), Cautin River, Temuco, what flattened on distal l/gth, gently re- 38°44'30"S, 72°35'00"W, C. G. Jara & R. curved. Rostral tip with acute scale. Rostral borders scarcely marginated, bearing mi- Navarro coll., 23 Dec 1982, IZUA C-322- nute scales along %\h of rostrum length, na- B. 8 males (11.7-21.9 mm LC), 8 females (17.8-24.7 mm LC), Chol-Chol River near ked distally. Rostral carina prominent and scaly half of length, Galvarino, 38°36'40"S, 72°51'05"W, C. G. on proximal rostrum absent on distal half; scales small, button- Jara & R. Navarro coll., 22 Dec 1982, like, in 2 subparallel rows. Epigastric prom- IZUA C-324-C. 12 males (12.4-27.3 mm inences forming low, smooth, arcuate ridge, LC), 9 females (12.5-21.2 mm LC), Lu- broadest just behind deepest point of orbital maco River at Pellahuen, 38°25'40"S, sinus. Protogastric prominences forming 72°56'00"W, C. G. Jara & R. Navarro coll., low tuberculiform area bearing short 22 Dec 1982, IZUA C-326-A. 1 juvenile oblique row of tiny stud-like scales. An- (5.6 mm LC), Pichicautin River near Lu- terolateral lobe of carapace and hepatic maco, 38°09'25"S, 72°54'15"W, T. Gonser lobes well defined; former elongated as coll., 16 Jan 1983, IZUA C-424. straight conical spine reaching up to middle Diagnosis. —Carapace slightly longer of adjacent cornea. Gastric area broad, pos- than wide, sparsely setose, moderately ex- terior more protuberant. Anterolateral angle panded at branchial level. Rostrum long, of first hepatic lobe spiniform; spine point- subtriangular, acute, styliform at distal half. ing straight forward. Branchial lobe pyra- Orbital spine prominent; extraorbital sinus midal, elongated, acutely tipped, well de- wide, U-shaped. Anterolateral angle of first tached from margin of third hepatic lobe hepatic lobe spiniform. Anterior branchial and from anterolateral angle of anterior margin subdenticulated; posterior finely branchial area; with single irregular row of serrated, dorsally upturned. Anterolateral acute scales on outer border. Branchial mar- angle of second abdominal epimeron spi- gins moderately expanded; anterior subden- niform. Fourth thoracic sternum with blunt ticulated, posterior finely serrated; denticles medial tubercle, occasionally with 1 or 2 on anterior margin short, ill-defined, except scales on frontal border. Telson divided. anteriormost which is as large as branchial Adult males markedly heterochelous; fe- lobe; each denticle carrying 3 to 4 tiny males weakly so. Chelae robust; propodus acute scales, mingled with short stiff setae. inflated though dorso-ventrally flattened; Dorsum of anterior branchial area flat to dactylar lobe blunt; palmar crest subrect- slightly concave; posterior branchial area angular or arcuate, expanded, dentated; pal- and adjacent marginal cardial area dome mar lobe low, blunt, with scales only on shaped; free border of posterior branchial frontal edge; medial scale largest; carpal area recurved and upturned. Anterolateral 110 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON angle of second abdominal epimeron spi- Quepe; all these are tributaries of the Im- niform; spine apex scarcely detached from perial River basin which discharge into the and at level with posterior branchial mar- Pacific Ocean, at Puerto Saavedra. gin. Lateral angle of third to fifth abdominal Habitat. —Aegla cholchol is found in me- epimera spiniform. Fourth thoracic sternum dium sized rivers (order 2 to 3, after Strah- with blunt median tubercle, occasionally ler, 1957) with coarse gravel and boulder carrying 1 or 2 scales on frontal border. Tel- substrates where water current velocity son longitudinally articulated. Chelae ro- varies between 0.1 to 0.7 m/sec. As a con- bust; propodus inflated though dorso-ven- sequence of intensive agricultural activity, trally flattened. Dactylar lobe, at proximo- the fluvial environment of some stretches of dorsal end of dactylus, blunt, with 1 to 4 the Chol-Chol River basin have undergone tiny scales in a row along apex. Palmar severe alterations; the riparian vegetation, crest subrectangular or arcuate, moderately mostly non-native species, is in a hetero- expanded, border coarsely dentated; teeth geneous state of conservation. At these subtriangular, recurved, apices point front- sites, specimens of A. cholchol, new spe- dorsally, especially the most distal. Palmar cies, were collected on coarse gravel to fine lobe, just behind dactylus-propodus joint, quartzitic micaceous sand, sharing the bio- blunt, low, with acute scales only on frontal tope with A. spectabilis. edge, its medial scale generally largest; Etymology.—The specific name is de- frontal border of palmar crest overhanging rived from the name of the type locality, as palmar lobe, separated by deep notch. Car- a latinized noun used in apposition. It is pal lobe prominent, massive, supporting ro- treated as indeclinable, for the purposes of bust, conical, acute, somewhat recurved Article 31b of the International Code of spine. Dorsointemal border of carpus, be- Zoological Nomenclature (International hind carpal lobe, with neat row of 2 to 3 Trust for Zoological Nomenclature 1985). large conical acute spines, decreasing in Affinities. —Aegla cholchol, new species, size towards rear. Carpal ridge as arcuate A. rostrata, and A. bahamondei are similar row of blunt knob-like tubercles topped by in appearance but the new species is more minute scale and/or short setae. Carpus ven- similar to A. rostrata than to A. bahamon- tral face with robust conical spine. Merus dei. Common to the three species is a wide of cheliped with row of blunt to spiniform carapace with expanded branchial areas and tubercles, distalmost largest; dorsodistal an- denticulated or subdenticulated branchial gle of merus tuberculiform, bearing group borders; steep inward downward inclination of short stiff setae, and 2 to 4 scales of of the branchiostegal surface; dorsum of an- which median is largest. terior branchial area subconcave; well de- Color. —Live, with dorsum of carapace fined branchial lobe; protuberant gastric and and abdomen olive green; sternal surface cardiac areas with elevated middorsal line and ventral face of pereopods creamy but non-keeled as in A. denticulata; acute white. Dorsum of pereopods with alternat- first hepatic angle and anterolateral angle of ing yellow green and dark green bars. Tip carapace; ample front and orbital sinuses of largest spines pale yellow to creamy, limited by acute orbital spines, one on the darkening to green at their base. Joints of plane of the orbital border and one just be- pereopods bright red, minutely spotted low the former, usually not visible from white. In alcohol, carapace and abdomen above; narrow, slightly troughed, elongated smoky tan to creamy white. and conically tipped rostrum. In each of the Geographic range (Fig. 3).—Found on three species, the appendages, especially the Chol-Chol River basin, from Lumaco to the chelipeds, present a basic morphologi- Chol-Chol; also in the Cautin River, in front cal pattern with proper modifications. The of Temuco, and in the Quepe River near new species differs from A. rostrata in hav- VOLUME 112, NUMBER 1 111

••— International BORDER REOIONAL BORDER

25 50 75 100 Km

Fig. 3. Map showing the geographical distribution of Aegla cholchol, new species. Asterisks indicate local- ities where specimens were collected. In some cases, asterisk indicates more than one sampling site. 112 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON ing: blunt tubercles on the carpal ridge; dor- of Cordillera Pelada (Coastal Range), Prov- sodistal angle of merus of chelipeds, sec- ince of Valdivia, Chile. ond, and third pereopods blunt, or at most, Type series. —Holotype: male (16.5 mm with small round tubercle tipped by minute CL), 26 Jan 1983, C. G. Jara coll., IZUA scales and/or setae; dactylar or palmar lobes C-245. Allotype: female (16.5 mm CL). not spiniform; edge of the anterior branchi- Paratypes: 7 males (10.9-19.7 mm LC), 3 al area subdenticulated, teeth apressed non females (14.1-14.6 mm LC), 2 juveniles spine-like; fourth thoracic sternum with me- (7.3-7.7 mm LC), same data as holotype. dian tubercle. Aegla cholchol, new species, Other material. —3 males (10.7-14.1 differs from A. bahamondei by having: epi- mm LC), 3 females (19.3-20.7 mm LC), branchial lobe monocuspidate; dactylar Chiveria, Cordillera Pelada, 40°04'50"S, lobe low and blunt; protogastric promi- 73°10'50"W, R. Formas coll., 14 Jan 1971, nences little protuberant; tubercle on fourth IZUA C-025. 5 females (12.1-18.1 mm thoracic sternum acute but non-spiniform; LC), Hueicolla River, 40°08'30"S, posteroventral edge of merus of second to 73°37'42"W, R. Formas coll., 1974, IZUA fourth pereopods smooth, non-denticulated; C-026. 14 males (8.9-18.3 mm LC), 7 fe- surface of carapace and chelae with few mi- males (1 1.7-16.4 mm LC), Amargos Creek, nute scales. Corral, Valdivia, 39°52'24"S, 72°26'25"W, Jara coll., Remarks. —A. cholchol, new species, A. C. G. 19 Mar 1974, IZUA C-042. 1 male (13.4 LC), 3 females (6.8-13.2 rostrata, and A. bahamondei share a series mm LC), Trainel River, Lago Huillinco, of complex characters. In particular, a ten- mm Chiloe, H. J. Wetzlar coll, 07 Oct 1975, dency to have every protruding angle of the IZUA C-131. 20 males (10.1-24.8 carapace, abdomen, and appendages, as a mm LC), 11 females (7.8-2L3 LC), San pointed conical tubercle or spine. However, mm Carlos Creek, San Carlos, Corral, Valdivia, the spines and spiniform tubercles are cer- 39°51'40"S, 73°26'25"W, C. G. Jara coll, 20 tainly more developed in A. rostrata than Mar 1976, IZUA C-175. 9 males (11.7- in A. cholchol, new species, and A. baha- 24.2 mm LC), 4 females (18.3-19.9 mm mondei. In the latter, the angles of the car- LC), Chiveria, Cordillera Pelada, apace are acute but never spiniform. Jara 40°04'20"S, 73°10'30"W, R. P Schlatter (1986:40) argued that "the trend toward coll., 21 Jan 1977, IZUA C-184. 3 males, profuse spinulation seems correlated with (12.3-18.3 mm LC), 9 females (10.9-17.6 living in lentic environments." In this con- mm LC), Hueicolla River, 40°08'30"S, text, both A. cholchol, new species, and A. 73°39'05"W, R. P Schlatter coll., 22 Jan bahamondei are restricted to rivers while A. 1977, IZUA C-185. 18 males (10.5-16.8 rostrata is found mostly in lakes. Jara mm LC), 8 females (10.2-14.6 mm LC), (1982:237) indicated that "some specimens Manzano River, ,

. .. found in Quepe River near Temuco ... Llanquihue, 41°07'20"S, 72°24'50"W, G. could prove to be conspecific with ... [A. Milhe coll., 26 Apr 1974, IZUA C-196. 3 bahamondeiy\ On reexamination, those males (11.3-14.6 mm LC), 4 females specimens proved to be A. cholchol, new (11.3-15.9 mm LC), Refugio River, Chiloe, species (IZUA C-008-B, formerly C-328). R. P Schlatter coll., 11 Oct 1977, IZUA C- 197. 2 males (8.3-23.6 mm LC), 1 female Aegla hueicollensis, new species (26.4 mm LC), Roblental Creek, eastern Figs. 4, 5a-i slope of Cordillera Pelada, 40°16'S, 73°12'W, C. G. Jara coll., 12 Feb 1978,

Type locality. — Pichihueicolla River, 0.5 IZUA C-206. 1 male (14.8 mm LC), 3 fe- km SE from its outlet into the Pacific Ocean males (15.7-21.4 mm LC), Pichihueicolla (40°10'S, 73°40'W), on the western slope River, 40°09'40"S, 73°39'50"W, C. G. Jara VOLUME 112, NUMBER 1 113

mm

Fig. 4. Aegla hueicollensis, new species, male holotype, Pichihueicolla River, IZUA C-245, dorsal view.

coll., 26 Jan 1982, IZUA C-246. 27 males IZUA C-364. 6 males (7.0-17.2 mm LC), (4.5-15.9 mm LC), 22 females (7.9-17.6 6 females (8.5-15.1 mm LC), Hueicolla mm LC), Hueicolla River, 40°09'07"S, River, 40°08'30"S, 73°31'38"W, H. F Jara 73°38'25"W, C. G. Jara coll., 27 Jan 1982, coll, 07 Feb 1992, IZUA C-507. 6 males

IZUA C-247. 5 males (10.3-19.7 mm LC), (9.6-16.7 mm LC), 1 female (13.9 mm 9 females (10.1-22.1 mm LC), Chaihmn LC), Hueicolla River, 40°08'27"S, River, 40°05'07"S, 73°2r51"W, C. G. Jara 73°30'39"W, H. E Jara coll, 08 Feb 1992, coll., 15 Feb 1984, IZUA C-363. 10 males IZUA C-508. (4.2-27.2 mm LC), 22 females (6.9-26.3 Diagnosis. —Carapace ovoidal, not ex- mm LC), Collin River, 40°02'31"S, panded at branchial areas. Epibranchial 73°31'26"W, C. G. Jara coll., 15 Feb 1984, lobe pyramidal, acute, borders scaly. Ros- 114 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON

Fig. 5. Aegla hueicollensis, new species, male holotype Pichihueicolla River, IZUA C-245; a, anterior part of cephalothorax, dorsal view; b, anterior part of cephalothorax, lateral view; c, third and fourth sterna; d, second

abdominal epimeron; e, telson plate; f, ischium of left cheliped, ventral view; g, carpus of left cheliped, ventral = view; h, left cheliped, dorsal view; i, merus of cheliped, lateral view. Scales: c, d, f, i = 1 mm; a, b, e, g, h 5 mm. VOLUME 112, NUMBER 1 115 trum short, wide at base, neatly triangular, angle of carapace short, acute, its apex both sides of low-profiled carina barely reaching up to proximal third of adjacent troughed, conical at apex, acute. First he- cornea. Orbital sinus wide, delimited by an patic lobe blunt. Orbital and extraorbital si- inconstantly present orbital spine; extraor- nus present. Branchial margin smooth, bital sinus variable in depth and width, gen- slightly nodulated. Second abdominal epi- erally narrowly V-shaped. First hepatic lobe meron acute but not spiniform. Telson di- blunt, well separated from base of antero- vided. Fourth thoracic sternum smooth. lateral lobe; second and third lobes scarcely Male chelae elongated, pyriform, inflated at defined, separated by shallow notches in- propodus; palmar crest flabelliform, sub- terrupting marginal row of scales. Branchial rectangular, dentate; dactylar lobe subspi- margin narrow, smooth, slightly nodulated; niform; carpal lobe spiniform, apex mark- posterior slightly upturned. Areola broad, edly displaced towards distal end of article, convex, elevated over remaining cardial frontal edge with row of tufts of short setae area. Thoracic sterna flat; fourth sternum mingled with scales; tubercles of carpal with frontal fringe of long stiff setae; sel- ridge blunt, low, topped by transversal row dom with low, blunt, median tubercle, car- of scales and setae. Tubercles on dorsal rying 1 or 2 scales. Anterolateral angle of edge of merus of chelipeds blunt, tipped by second abdominal epimeron acute, dorsum 2 to 4 scales roughly ordered in transversal subcarinate behind anterolateral angle; la- oblique row. Ventroextemal border of is- teroventral face of epimeron deeply con- chium, ventral face of carpus, and ventral cave, profusely covered by short stiff setae; borders of chelae with tufts of long setae in free ventral border with dense row of long row. plumose setae, also present over posterior Description. —Carapace surface finely branchiostegal surface, edge of remaining punctated, each pit with a minute scale and abdominal epimera, and borders of uropods

1 or 2 short stiff setae; highest density of and telson. Telson longitudinally articulat- setae on abdominal epimera. Precervical ed. carapace almost as wide as postcervical. Males heterochelous; left hand largest.

Epibranchial lobe pyramidal, acute, its edg- Chelae robust but not particularly massive, es lined with short acute stout scales; sim- subovoidal in outline, surface microtuber- ilar scales along outer borders of carapace culate; each tubercle carrying a minute except for posterior border and external half acute scale and 2 short stiff microsetae, of orbital sinus. Rostrum short, wide at most evident on distal half of propodus and base, neatly triangular, barely troughed; dactylus. Molar process well developed on low-profiled carina merges into rostrum cutting edge of fixed finger and dactylus of body at proximal half; rostral apex conical, left chela but negligible or absent on right with stout acute apical scale encircled at one. Dorsum of dactylus with robust spi- base by 3 to 4 minor scales; dorsum of ca- niform lobe on proximal end. Ventral face rina with double row of tiny scales proxi- of chelae with prominent ridge along ven- mally, and single unordered row distally; troextemal border of propodus, marked by ventral carina not particularly prominent, its row of pits and tufts of long setae; pits more deepest point at base. Epigastric promi- numerous along dactylus and fixed finger. nences nodular, blunt, topped with 3 to 4 Base of palmar crest on ventral side of che- scales in transverse row; protogastric prom- lae parallel to short tuberculate ridge with inences barely discernible, marked by small large pits and tufts of setae. Central part of field of button-like scales mingled with stiff ventral face of chelae broadly convex, setae. Anterolateral lobe of carapace later- forming longitudinal ridge between center ally expanded, flattened proximally, its ex- of propodus-carpus joint and distalmost ternal border slightly sinuose; anterolateral dactylus-propodus joint, marked by large 116 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON pits and setae. Palmar crest prominent, lada (Coastal Range between Corral to the

thick, its border denticulated with scattered north and the outlet of the Bueno River to small acute scales between contiguous larg- the south). Specimens collected are from: er denticles. Distal end of palmar crest sep- Amargos Creek (Corral, Valdivia), Colun, arated from predactylar lobe of carpus by Chaihuin, HueicoUa, and PichihueicoUa riv- almost right-angled deep notch; predactylar ers. Also found in Manzano River, at Todos lobe elevated, its free border with irregular Los Santos Lake, in the Andean district of row of short acute scales; largest scale at the Llanquihue province. anterodorsal angle. Carpus robust, with two Habitat. —Small rivers and fast flowing dorsal ridges; outermost lower, distinguish- streams on moderate to steep slopes, cov- able as slightly arcuate row of broad low ered or surrounded by cold-temperate Val- tubercles; apex of tubercles with row of 3 divian rain forest. Specimens are found to 6 short stiff setae mingled with minute among pebbles and boulders on the stream scales; innermost prominent, formed by bottom, at sites where a heterogeneous row of blunt tubercles topped by tranverse mass of vegetal detritus accumulates serv- row of 3 to 5 acute scales and setae. Carpal ing as shelter for the crabs. lobe spiniform, asymetrically subtriangular, Etymology.—The specific name derives apex leveled with frontal border of same from Hueicolla, a small town on the Pacific lobe. Inner border of carpus with row of 3 coast about 40 km to the south from Corral, large spines proximally decreasing in size. where the rivers Hueicolla and Pichihuei- Dorsum of anteriormost spine with 2 to 3 coUa discharge into the Pacific Ocean. scales or setae protruding from large pits in Affinities. —Aegla hueicollensis, new spe- a row along spine axis. Same arrangement cies, shares a series of features with other

on minor spines or at least, 1 pit and setae species of Aegla. In general, the new spe- present. Ventral surface of carpus with ro- cies closely resembles A. abtao. Several bust conical spine; between it and inner morphological similarities suggest a close border of carpus several thick, long, simple ancestral relationship between the two. A. setae, uneven in size. Dorsal edge of merus hueicollensis, new species, also displays

with row of subacute tubercles tipped by 1 morphological similarity to A. alacalufi. or 2 scales, 3 or 4 on distalmost tubercle; Both share the almond-shaped outhne of frontal side of tubercles with tufts of long the carapace, the short triangular acute ros- simple setae; frontodorsal angle blunt, trum, and the pronounced distalward dis-

thick, little prominent, with patch of short placement of the apex of the carpal lobe. stiff setae and scales; ventral borders with However, A. alacalufi has an undivided tel- row of tubercles tipped with scale and/or son plate, and lacks minute scales on the seta; distal angles as short conical spine. carapace surface. The new species also Dorsal edge of merus of second, third and shares features with A. manni and A. neu- fourth pereopods with fringe of long plu- quensis Schmitt, 1942b, such as: the irreg- mose setae covering minute spiniform tu- ular row of scales and/or setae along the bercles; carpus, propodus and dactylus with dorsal axis of the larger spines on the inner fringe of short stiff simple setae. Postero- border of carpus of chelipeds and the trans- ventral edge of merus scabrous, subserrat- verse row of scales on the tubercles of the ed, with narrow band of setae and scales. carpal ridge of chelae. The new species dif- Color. —Not observed live. In alcohol, fers from A. manni in having the rostral ca- carapace, abdomen, and appendages uni- rina and rostral margins scaly; from A. neu- formly smoky-tan to creamy white. quensis by having the anterolateral angle of Geographic range (Fig. 6). Small second abdominal epimeron subspinose. streams and creeks flowing from east to The low, somewhat concave, profile of the west on the western slope of Cordillera Pe- rostral carina and the protuberant gastric VOLUME 112, NUMBER 1 117

Fig. 6. Map showing the geographical distribution of Aegla hueicollensis, new species. Asterisks indicate localities where specimens were collected. In some cases, asterisk indicates more than one sampling site. 118 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON area of A. hueicollensis, new species, re- material; Dr. Rafael Lemaitre and two semble those of A. concepcionensis. These anonymous reviewers for their efforts to similarities led Schmitt (1942b:504) to re- improve the readability of the manuscript. port specimens of Aegla from Corral The present paper was financed by grants (northern limit of Cordillera Pelada) as A. 91-0900 of the Fondo de Investigacion concepcionensis. Similarly, Haig (1955: Cientifica y Tecnologica (Fondecyt, Chile) 504) classified as A. concepcionensis spec- and S-91-4 of the Direccion de Investiga- imens from Ancud (230 km to the south of cion y Desarrollo, Universidad Austral de Corral), Chiloe Island. To determine if these Chile. specimens are conspecific with A. hueicol- lensis, new species, they would have to be Literature Cited re-examined. Bahamonde, N., & M. T Lopez. 1963. Decapodos de Remarks. —The geographic range of A. aguas continentales en Chile.—Investigaciones hueicollensis, new species, includes a series Zoologicas Chilenas 10:123-149. of localities on the western slope of the Borgel, R. 1983. Geomorfologia. in Geografia de Chile, 2. Institute Geografico Militar, Santiago, Coastal Cordillera and one locality (Man- Chile, 182 pp. zano River) on the western slope of the An- Di Castri, F. 1968. Esquisse ecologique du Chili. Biol- des Cordillera, about 100 km southeast of ogie de TAmerique Australe. Pp. 7-82 in C. the type locality. There is no hydrological Delamare Deboutteville & E. Rapoport, eds.. connection between these areas at present. Biologic de TAmerique Australe, 4. Editions du Centre National de la Recherche Scientifique, This fact leads to the assumption that, in Paris, 685 pp. the past, the geographic range of the new Haig, J. 1955. The Crustacea Anomura of Chile.—Re- species must have been broader, enclosing ports of the Lund University Chile Expedition localities on the intervening territory be- 1948-49, 20. Lund Universitets Arsskrift. N.F tween the Andean and the Coastal ranges. Avd. 2, 5 1(12): 1-68. lilies, H. 1960. Geologic der Gegend von Valdivia Connected to this is the fact that southern (Chile).—Neues Jahrbuch fiir Geologic und Pa- Chile, from paralell 38°S southward, was lacntologie 111:30-110. (Translated into Span- severely affected by Quaternary glaciations. ish by J. Walper. Universidad Austral de Chile, lilies (1960) found evidence that during Valdivia, 1970, 50 pp.) glaciations the ice-sheet front advanced International Trust for Zoological Nomenclature. 1985. International Code of Zoological Nomenclature, west from the Andean highlands completely Third edition, London, 338 pp. covering the Central Valley; the ice front Jara, C. 1977. Aegla rostrata, n. sp. (Decapoda, Ae- pushed upon the eastern slope of the Coast- glidae), nuevo crustaceo dulceacuicola del Sur al Range but never surmounted it. The de Chile.—Studies on Neotropical Fauna and western slope of the Coastal Range which Environment 12:165-176.

. 1980. Dos nuevas especies de Aegla Leach was never completely covered by ice (lilies (Crustacea, Decapoda, Anomura) del sistema 1960) could have served as a refugial area hidrografico del Rio Valdivia.—Anales del Mu- for A. hueicollensis, new species. Its pres- seo de Historia Natural de Valparaiso 13:255- ence in the small Manzano River basin, 266.

amid the Andean massif, presumes that . 1982. Aegla bahamondei, new species (Crus- tacea: Decapoda: Anomura) from the Coastal somehow the site was unaffected by de- Mountain Range of Nahuelbuta, Chile.—Jour- structive glacial effects, thus preserving the nal of Crustacean Biology 2(2):232-238. preexisting population. . 1986. Aegla spectabilis, a new species of freshwater crab from the eastern slope of the Nahuelbuta Coastal Cordillera, Chile.—Pro- Acknowledgments ceedings of the Biological Society of Washing- ton 99:34-41. The authors thank Drs. R. Formas, T . 1989. Aegla denticulata lacustris, new sub- Gonser, H. F. Jara, R. Navarro, and R. R species, from Lake Rupanco, Chile (Crustacea: Schlatter for the presentation of valuable Decapoda: Anomura: Aeglidae).—Proceedings —

VOLUME 112, NUMBER 1 119

of the Biological Society of Washington 102: Nicolet, H. 1849. Crustaceos. Pp. 113-318 in C. Gay,

385-393. Historia Fisica y Politica de Chile, Zoologia 3, — . 1992. Aegla expansa, new species (Crustacea: 547 pp. Decapoda: Anomura: Aeglidae), from the Low- Schmitt, W. L. 1942a. Two new species of Aegla from er Bio-Bio river basin, Concepcion, Chile. Chile.—Revista Chilena de Historia Natural Gayana (Zoologia) 56(l-2):49-57. 44(1940):25-31, pi. 1.

— . 1994. Aegla pewenchae, new species of Cen- . 1942b. The species of Aegla, endemic South tral Chilean freshwater decapod (Crustacea: An- American freshwater crustaceans.—Proceedings omura: Aeglidae).—Proceedings of the Biolog- of the United States National Museum 91:431- ical Society of Washington 107:325-339. 520. -, & M. T. Lopez. 1981. A new species of fresh- water crab (Crustacea: Anomura: Aeglidae) Strahler, A. N. 1957. Quantitative analysis of water- from insular South Chile.—Proceedings of the shed geomorphology.—Transactions of the Biological Society of Washington 94:88-93. American Geophysicists Union 38:13-920.