Bryocamptus (Bryocamptus) gauthieri ( Roy, 1924 )

Fiers, Frank, 2013, Bryocamptus (Bryocamptus) gauthieri (Roy, 1924): a Mediterranean edaphic specialist (Crustacea: Copepoda: Harpacticoida), Revue suisse de Zoologie 120 (3), pp. 357-371 : 358-368

Bryocamptus (Bryocamptus) gauthieri ( Roy, 1924) Figs 1-6

Canthocamptus­Gauthieri - Roy, 1924: 461-468, figs 1-19.

Canthocamptus­Gauthieri Roy, 1924 - Roy & Gauthier, 1927: 571; Kiefer, 1928: 90, 91, 107; Chappuis, 1928: 127 [key].

Bryocamptus­Gauthieri Roy, 1924 [sic] - Rose & VaissiÈre, 1952: 134.

Bryocamptus (s. str.) Gauthieri ( Roy, 1924) - Chappuis, 1929a: 44; Chappuis, 1929b: 479.

Bryocamptus (Bryocamptus) gauthieri ( Roy, 1924) - Chappuis, 1944: 385, 390-391 [key]; Lang, 1948: 1064-1065 [key], 1084, fig. 431(1); Wells, 2007: 46, 294, 295 [key].

Bryocamptus (Rheocamptus) gauthieri ( Roy, 1924) - Borutzky, 1952: 172,199 [key]; Borutzky, 1964: 154,180-181 [key]; Dussart & Defaye, 1990: 160; Mouelhi et­al., 2000: 740.

TYPE LOCALITY: Algeria, Baba-Ali , south of Algiers; among humid moss ( Roy, 1924).

MATERIAL EXAMINED: (1) Lebanon. Sieving of roots and leaf litter collected at the bottom of a rock wall in a small oak forest near the mouth of the river Nahr Damour ; leg. Cl. Besuchet, 4 April 1975 (sample Lebanon 17c, Berlese extraction at MHNG): 8♀, 23 (2♀, 13 dissected, remaining specimens preserved) ;

(4) Cyprus. Besparmaklar (= Pezntadactylos), Daglari chain, east of Kantara Castle , leaf litter below Arbulus hedge row, leg. S. Vit, 10 April 1998 (sample Chypre 118) : 1♀ (preserved undissected);

(5) Greece, Samos (Island). Along route Platanakia (east of Aghios Konstantinos ) to Manolates, “Nightingale” valley below Manolates, forest along brook along road, 80 m a.s.l., soil sample from inside hollow Platanus, leg. B. Hauser, 26 November 1991 (sample ZS-91/61, Berlese extraction at MHNG): 1♀, 1 copepodid (♀ dissected, copepodid preserved) ;

(6) Greece, Epira. Near Meniaion (south of Arta in Epirus region), sieved remnants of maquis litter collected in a humid canyon, leg. S. Vit, 29 March 1978 (sample Greece 12): 1♀, 1 copepodid (both preserved) .

Specimens featuring in Roy’s (1924) description are not available anymore (Defaye, in­litt. Aug. 2012). Neither are any voucher specimens left that were identified by Kiefer (1928) in the samples obtained at Azrou ( Franke, 1989; pers. obs. in 2008). Two slides labelled “ C.­gauthieri­ Algiers ” with a female and a male specimen, respectively, and a vial labelled “ C.­ gauthieri Roy ” containing 6 ♀ and 3 3, were localized in the Chappuis collection at Cluj ( Romania). It is assumed that these specimens originate from the series examined by Roy and were obtained by Chappuis in the course of his revision of the Canthocamptidae ( Chappuis, 1929a,b). Unfortunately, no formal confirmation of an exchange between Roy and Chappuis is available (neither in Cluj, pers. obs., nor in Paris, D. Defaye, in­ litt.). The status of the specimens cannot be ascertained, but they are highly eligible to be the syntypes because in the process of evaluating and cataloguing the Chappuis collection at Cluj it became apparent that a lively exchange between Chappuis and his colleagues existed.

The following description is primarily based on examination of the material from Lebanon. Variability observed within the Lebanese population and among the specimens from other localities is dealt with where appropriate. Particularities observed in the specimens from the Chappuis collection (hereafter indicated: Algiers) are emphasized and illustrated separately.

DESCRIPTION: Female. Habitus (Fig. 1A): body fusiform in dorsal view; prosome and urosome equally long, with distinct principal body articulation; cephalothorax rather short, less long than metasome, with dorso-median keyhole-shaped integumental window; metasomites without lateral integumental windows; integument of cephalothorax and metasomites devoid of integumental ornamentation; hyaline fringes of cephalothorax and pedigerous somites straight, of genital double-somite and urosomites 4-5 minutely indented; body length 450-470 µm ( Algiers 370-435 µm).

Genital double-somite (Fig. 2A) approximately 1.3 times wider than long, with divergent lateral margins and faint medial constriction; without remnants of ancestral subdivision; integument smooth except for postero-lateral row of narrow spinules; number of spinules variable, ranging between 4 and 15, often unequal in number on either side of a specimen (see arrows in Fig. 1D); postero-ventral margin (Fig. 2A) and ventral half of postero-lateral margin (Fig. 1D) of urosomites 4 and 15 set with long spinules, interrupted mid-ventrally on urosomite 4, uninterrupted on urosomite 5; anal somite without ornamentation along postero-dorsal border; postero-lateral and posteroventral border with spinules, both series well separated from each other by distinct gap; medial spinules of postero-ventral series shortest; anal operculum with smooth cres-

FIG. 1

Bryocamptus (B.) gauthieri ( Roy, 1924) ; Lebanese specimens. (A) Female habitus, dorsal view. (B) Principal setae of caudal rami. (C) Male habitus, dorsal view. (D) Female abdomen, lateral view (alternative spinule ornamentation on genital double-somite inserted, see arrows).

centic border, moderately expanded, but not reaching beyond caudal margin of anal sinus; dorsal surface of anal operculum smooth.

Caudal rami (Figs 1A, D, 2A, 6A, B) sub-rectangular, about 1.25 times longer than wide, without particular modifications on dorsal surface; both antero-lateral setae

FIG. 2

Bryocamptus (B.) gauthieri ( Roy, 1924) ; Lebanese specimens. (A) Female abdomen, ventral view. (B) Male urosome, ventral view.

inserted half-way on outer margin, accompanied with 2 minute spinules near insertion; postero-lateral seta inserted close to outer distal corner, distinctly longer (about 1.4- 1.5 times) than longest antero-lateral one, and accompanied with 2 large spinules near insertion; principal terminal setae with breaking plane and ornamented with short and stiff hairs; outer terminal seta half as long as inner one; medial seta longer (about 1.5 times) than ramus, with short cylindrical expanded proximal part and inserted on inner ventro-medial edge of ramus; insertion and expansion of medial element hidden behind 4-5 large spinules; dorsal seta articulating on short basal part.

Antennule (Figs 3A, 6C): 8-segmented, with following armature (proximal to distal segment): 1(1)-2(9)-3(6)-4(2+Aesth)-5(2)-6(3)-7(2)-8(7+Aesth); principal aesthetsac (on segment 4) wide, linguiform and reaching distal margin of segment 7; terminal aesthetasc slender, tubiform and about 1.5 times longer than segment 8; integument of segments smooth except for short spinule row in proximal half of frontally directed margin of segment 1.

Antenna (Fig. 3B, C): coxal pedestal large and naked; allobasis with 2 abexopodal setae and 2-segmented exopodite; endopodite segment with 3 lateral elements (2 spines, 1 seta) and 6 terminal ones (2 spines, 3 geniculate seta, 1 dwarfed seta); abexopodal margin of endopodite segment with 3-4 robust spinules; exopodite with 1 and 3 setae on proximal and distal segment, respectively; spinules near articulation between proximal and distal segment present.

Mandible (Fig. 3D): gnathobasis with multi-cuspidate teeth; palp onesegmented, cylindrical, twice as long as wide and bearing 2 terminal setae. Maxillule (Fig. 3 E): arthrite with 6 median spines, 2 lateral setae, and 2 long narrow surface elements; coxal endite with 2 medial elements; basis with 2 medial and 2 subterminal setae; rami obsolete, represented by 3 setae; integument of maxillule naked. Maxille (Fig. 3F): syncoxal endites cylindrical, bearing 3 distal elements (1 with long setules along stem); basis claw-shaped, with few weak teeth and 2 setae; endopodite vestigial, represented by 3 setae. Maxilliped (Fig. 3G): syncoxa with short medial tuft of spinules and single medial pinnate element; medial margin of basis set with comb of rigid spinules; outer margin of basis with 3 clusters of spinules; claw serrate in distal half and accompanied with slender seta.

Leg 1 (Figs 4A, B, 6D): intercoxal sclerite wide, naked, with concave distal border; coxa with frontal and caudal combs of spinules; basis with ornamentation on frontal surface only; outer and inner element on basis spiniform, both with terminal flagellum; outer element naked, medial one serrate; exopodite 3-segmented, endopodite 2-segmented; armature distribution given in Table 1; endopodite, composed of two equally long segments, reaching only half-way terminal exopodite segment; medial element on second exopodite segment long and pectinate; terminal medial elements on third exopodite segment geniculated; proximal endopodite segment with or without medial spinule and lacking medial element; medial margin of distal endopodite segment with one or two medial spinules, terminal claw moderately long.

Legs 2-4 (Figs 4C, 5A, 5G, respectively): pre-coxal fold unadorned; intercoxal sclerite with narrow crescentic depression mid-distally; coxa and basis with row of spinules near outer frontal border, with additional spinule row near medial frontal border in leg 2 (Fig. 4C); outer element on basis of leg 2 spiniform with terminal flagellum; outer element on basis of legs 3 and 4 setiform; exopodites 3-segmented, endopodites 2-segmented; armature distribution given in Table 1; medial element(s) on second and third exopodite segment in each leg pectinate; leg 2 endopodite reaching beyond articulation between second and third exopodite segment, leg 3 and leg 4 endopodites shorter; leg 2 with variable armature and ornamentation: proximal segment either with (Fig. 4I, J) or without seta (Figs 4C, E-H, K, 6F), with (Figs 4C-H, 6F) or without (Fig. 4H-J) medial spinule; distal segment with 2 medial short setae (Fig. 4C,

FIG. 3

Bryocamptus (B.) gauthieri ( Roy, 1924) ; female (A-G), male (H); Cypriot specimens (E-F), Lebanese specimens (A-D, G-H). (A) Antennule contour with principal aesthetasc, ventral view. (B) Antenna, inner view, exopodite omitted. (C) Antennary exopodite. (D) Mandible. (E) Maxillule (precoxal arthrite detached). (F) Maxille. (G) Maxilliped. (H) Antennule contour with aesthetascs and modified seta on segment 4, ventral view.

6F) or 2 dwarfed elements (Fig. 4K), 1 normal seta (Fig. 4E, H) or 1 dwarfed one (Fig. 4F, J), or without armature (Fig. 4G, I) and a variable (from 0 to 2) number of spinules; leg 3 endopodite generally with medial seta on proximal segment (Figs 5A- C, E-F, 6G) rarely without (Fig. 5D); distal leg 3 endopodite segment with 2 medial elements, inserted in distal third of medial margin (Figs 5A-C, F-E, 6G), rarely widely separated from each other (Fig. 5D); proximal endopodite segment of leg 4 short and narrow; inner armature element on second endopodite segment long and pectinate: apical setae long, outer one shorter than inner one; leg 4 endopodite (Figs 5G, 6E) slender, with spinule in distal half of outer margin of distal segment, unadorned along medial margin.

TABLE 1. Leg armature distribution.

EXO ♀ and 3 END ♀ END 3

Leg 1 I,0 - I,1 - II,2,0 0,0 - I,1,1 idem

Leg 2 I,0 - I,1 - II,2,1 0,0/0,1 - I,2,0/I,2,1/I,2,2 0,0 - 0,2,0

Leg 3 I,0 - I,1 - II,2,2 0,0/0,1 - I,2,2 0,1 - Apo - 0,2,0 Leg 4 I,0 - I,0 - II,2,2 0.0 - I,2,1 0,0 - 0,2,0

Leg 5 (Fig. 5J, K): baseoendopodite prominent, reaching beyond exopodite, bearing 6 setae on linguiform expanded endopodite lobe; distal margin of baseoendopodite with 3 blunt expansions along caudal border (see Fig. 5J); exopodite ovate, 1.5 times longer than wide, bearing 5 elements; setae on both rami sparsely pinnate, except for smooth outer distal seta of exopodite segment; surface of segments smooth; intercoxal sclerite well defined, with convex distal margin.

Leg 6 (Fig. 2A): vestige slightly protruded caudally, bearing single long, sparsely pinnate element; remnants of both medial traces minute, hardly discernable, with hyaline appearance; surface of vestige smooth; lateral combs of spinules near leg 6 vestige present; genital complex with long and wide, caudally directed copulatory funnel with entrance mid-ventrally in caudal third of genital double-somite; pore orifice at each side of copulatory funnel, situated half-way funnel length.

Male. Habitus (Fig. 1C): body fusiform in dorsal view, with obvious principal body articulation; length 355-360 µm ( Algiers 295-300 µm), widest near posterior margin of cephalothorax; medio-dorsal integumental window on cephalothorax less wide than in female; integument of prosomites and first urosomite devoid of ornamentation, hyaline fringes straight; urosomites 2-5 with serrate hyaline fringe; urosomite 2 (leg 6 pediger) with short dorsolateral spinule row along posterior border (visible in dorsal and lateral view only); urosomites 3-5 with uninterrupted row of spinules along postero-dorsal and postero-lateral margin (Fig. 2B); anal somite (incl. operculum) and caudal rami as in the female.

Antennule (Fig. 3H): 9-segmented, haplocer, with first and second segment as in female (bearing 1 and 9 setae, respectively); segment 4 with robust, inflated and unarmed mid-lateral element on inner side; principal aesthetasc wide and linguiform, fused with seta at basis; terminal aesthetasc slender, tubiform and little longer than terminal segment; inner margin of segments 5-6 with large ovate cushion-shaped elements; penultimate and ultimate segment unmodified; exact armature number on segments 3-7 not observed (broken or clustered and covered by dirt). Mouthparts as in female.

Leg 1 as in female; protopodite and exopodite of legs 2-4 as in female; proximal endopodite segment of leg 2 (Fig. 4D) with medial spinule, lacking medial element; distal segment tapering apically, with pore orifice in proximal half of medial border (associated with a spinule), and subapically on outer margin; terminal elements setiform; leg 3 endopodite 3-segmented (Fig. 5H); proximal segment short, with medial seta; middle segment with long (2.5 times longer than terminal segment length), nearly straight apophysis; tip of apophysis half-arrow-shaped; third segment rather long (3-3.5 times longer than wide), with subdistal depression (with short tubular pore

FIG. 4

Bryocamptus (B.) gauthieri ( Roy, 1924) ; female (A, C, E-K), male (B, D); Lebanese specimens (A-G); Cypriot specimens (H-K). (A) Leg 1, frontal view. (B) Leg 1, medial region, caudal view. (C) Leg 2, frontal view. (D) Leg 2, medial region, caudal view. (E-K) Leg 2 endopodite variability in Lebanese specimens (E-G) and Cypriot specimens (H-K).

orifice), and 2 pinnate apical setae; leg 4 endopodite (Fig. 5I) shorter than in female, its second segment with 2 stiff terminal elements (outer one shorter than inner one) and with a single spinule in distal half of outer margin.

Leg 5 (Fig. 2B): opposite legs confluent midventrally; endopodite lobe prominent, linguiform, bearing 2 distal elements; endopodite spines either equally long, or medial one slightly longer then outer one; exopodite 1.5 times longer than wide, reaching beyond endopodite lobe, bearing 6 elements: 2 medial, 2 apical and 2 outer ones; outer apical and outer lateral ones smooth, inner apical and medial ones pinnate; integument of both rami naked.

Leg 6 (Fig. 2B): left one functional, right one not; both with 3 elements: outer and middle one long, medial one short (about 1/3 of middle one); surface of valves smooth.

VARIABILITY: The body length of most specimens from Algiers appears to be considerably shorter than that of animals from the other localities. The Algerian specimens are, however, compacted probably as a result of fixation. Roy (1924) already noted the wide range of the body lengths (0.40-0.62 mm for females, 0.36-0.53 mm for males) in the original sample.

Ornamentation of the urosomal somites observed is consistent with the pattern given in the original description. The spinule row along the posterolateral margin of the genital double-somite in the female may be composed of only a few spinules, but is in most cases a well defined row with up to 15 spinules present. The anal operculum of all specimens examined, including those from Algiers, is devoid of ornamentation on the dorsal surface (except for the usual pair of sensilla). The transverse rows of spinules (1 in the female, 2 in the male) emphasized in the original description are in reality located along the border of the anal sinus at the ventral surface of the operculum and are visible depending on the transparency of the anal operculum. The presence of anal operculum ornamentation has been used as a diagnostic feature ( Lang, 1948; Borutzky, 1952, 1964) but that has to be ignored. Adornment of the endopodite segments of legs 1-4 shows variability and may be different on both sides of the same pair of legs. Variation is particularly noticeable on the medial margin of the endopodite segments on which spinules may be present. In most cases, however, the medial margin is unadorned.

The variation of the endopodite armature of leg 2, and to a lesser degree of leg 3, is summarized in Table 1. The armature of leg 1 and leg 4, as well as the structure and setal armament of leg 5, appear to be constant, but whereas the armature of legs 4 and 5 coincide completely with the original description, that of leg 1 differs in the absence of an inner distal element on the proximal endopodite segment. Roy (1924) clearly mentioned the presence of a seta and illustrated a strikingly short and filiform structure arising from the medial distal corner of the segment. The uncommon nature of this structure, compared to the habitual morphology of this element in other species of the genus, has been noticed by Lang (1948: 910: footnote to tab. 16). Moreover, the extreme distal insertion of this structure as illustrated by Roy is odd and is in contradiction to the habitual subdistal position of a medial element. Lang’s remark, the aberrant position and the fact that a comparable structure has not been observed among

FIG. 5

Bryocamptus (B.) gauthieri ( Roy, 1924) ; female (A-G, J-K), male (H-I); Lebanese specimens (A-C, G-I, J), Cypriot specimens (D-F, K). (A) Leg 3, frontal view. (B-F) Leg 3 endopodite variabitlity in Lebanese specimens (B-C) and Cypriot specimens (D-F). (G) Leg 4, caudal view. (H) Leg 3 medial part, frontal view. (I) Leg 4 medial region, frontal view. (J) Leg 5 contour, caudal view. (K) Leg 5, frontal view.

FIG. 6

Bryocamptus (B.) gauthieri­ ( Roy, 1924), female specimen from Algiers from Chappuis collection. (A) Anal somite and caudal rami, dorsal view. (B) Idem, ventral view. (C) Antennule, partially exploded, ventral view. (D) Leg 1 endopodite, frontal view. (E) Leg 4 endopodite, caudal view. (F) Leg 2 endopodite, frontal view. (G) Leg 3 endopodite, frontal view.

the specimens examined indicate that the leg 1 endopodite of B.­ gauthieri lacks a medial armature element. The structure described by Roy is either a spinule or is based on an erroneous observation.

One female from Algiers has an aberrant antennule in which segments 4-8 are deformed into a single short square segment bearing a few setae and a terminal aesthetasc. Segments 1-3 possess a normal morphology and setal armature. The principal aesthetascs on the female antennules of some Algerian specimens are shorter (reaching only the distal margin of segment 6) and less wide than those observed in the other populations. The irregular and undulated shape in the distal half of the aesthetascs (Fig. 6C) is presumably due to fixation.