Galathea humilis Nobili, 1905: 397
Nobili, 1906a: 124
Doflein & Balss, 1913: 169
Lewinsohn, 1969: 117
Coralliogalathea humilis ( Nobili, 1905 )
Baba & Javed, 1974: 62
Tirmizi & Javed, 1993: 37
Coralliogalathea humilis
C. tridentirostris ( Miyake, 1953 )
C. tridentirostris
C. humilis
C. humilis
C. megalochira
C. minuta
C. parva
Original Article High morphological similarity coupled with high genetic differentiation in new sympatric species of coral-reef squat lobsters (Crustacea: Decapoda: Galatheidae)
Rodríguez-Flores, Paula C.
Macpherson, Enrique
Buckley, David
Machordom, Annie
Zoological Journal of the Linnean Society
2018
185
984
1017
B8CHG
(NOBILI, 1905)
Nobili
1905
[216,725,797,822]
Malacostraca
Galatheidae
Coralliogalathea
CoL,GBIF
Animalia
Decapoda
10
994
Arthropoda
species
humilis
( FIGS4, 5A, B)
Galathea humilis Nobili, 1905: 397. – Nobili, 1906a: 124, pl. 8, fig. 4. – Doflein & Balss, 1913: 169[list]. – Lewinsohn, 1969: 117, fig. 22. Coralliogalathea humilis( Nobili, 1905): Baba & Javed, 1974: 62. – Tirmizi & Javed, 1993: 37, fig. 16.
Material examined Syntypes:Red Sea. Djibouti, H. Coutiere, collected, 1897: three M, 1.9–2.0 mm, two ov. F, 2.1–2.3 mm(MNHN-IU-2013-17324). Red Sea. Saudi Arabia. Farasan Banks, Dolphen Lagoon, 19.0053°N, 40.1482°E, 1–7 m, 4 March 2013: one ov. F, 2.0 mm ( UF36151). – Farasan Banks, Marca Is., 18.2206°N, 41°3244°E, 5–15 m, 6 March 2013: one ov. F, 2.1 mm( UF36158). – Farasan Is., Zahrat Durakah, 16.8359°N, 42.3063°E, 2–6 m, 11 March 2013: one M, 1.6 mm( UF37026). – Al Lith, 20.1672°N, 40.2233°E, 1–2 m, 21 March 2013: one ov. F, 2.1 mm( UF37156). – off Thuwai, Abu Shosha Reef, 22.2044°N, 39.047°E, 7–8 m, 23 March 2013: three M, 1.4–1.6 mm( UF37403).– Jaz’air, 27.6384°N, 35.3062°E, 10 m, 27 September 2013: one ov. F, 2.7 mm, one F, 1.3 mm( UF36439). – Gulf of Aqaba, 28.4039°N, 34.7407°E, 7–8 m, 29 September 2013: one M, 1.4 mm( UF38080). – 28.1846°N, 34.6381°E, 3–10 m, 1 October 2013: one M, 1.2 mm( UF38193). – Shi’b Al Khamsa, 38.6163°N, 22.7489°E, 8 m, 6 March 2014: one M, 1.7 mm( UF40269). – Wajh Barrier, 25.407°N, 36.690°E, 5–7 m, 30 January 2016: one ov. F, 1.9 mm( UF42374). – Wajh Barrier, 25.407°N, 36.690°E, 5–7 m, 30 January 2016: one ov. F, 2.3 mm( UF42390). Madagascar. Tulear, coll. Thomassin. Stn489: one ov. F, 2.5 mm(MNHN-IU-2013-17320). – Stn 498, one M, 2.2 mm(MNHN-IU-2013-17322). – Stn 617, one M, 1.8 mm(MNHN-IU-2013-17309). – Stn 678, one juv., 1.0 mm (MNHN-IU-2013-17310). – Stn 761, two M, 1.7–1.8 mm, one F, 1.6 mm, one juv., 1.0 mm (MNHN-IU-2013-17312). – Stn 762, one juv., 1.0 mm (MNHN-IU-2013-17316). – Stn 775, one M, 1.8 mm, one F, 1.6 mm(MNHN-IU-2013-17313). – Stn 844B, two M, 1.5–1.9mm,five F, 1.5–2.4mm(MNHN-IU-2013-17319). – Stn 896, nine M, 1.2–2.2 mm, five ov. F, 2.2–2.6 mm, two F, 1.9–2.1 mm(MNHN-IU-2013-17311). – Stn 902A, two M, 1.8–1.9 mm, one ov. F, 1.9 mm, one F, 1.7 mm(MNHN-IU-2013-17318). – Stn 1635, one ov. F, 2.0 mm, one juv., 1.0 mm (MNHN-IU-2013-17315). Other material: Red Sea. Djibouti. Moucha Is., Maskali Bank, 11.6992°N, 43.1432°E, 7–17 m, 27 September 2012: two M, 1.3–2.0 mm, one ov. F, 1.6 mm( UF33346). Red Sea. Jubal, Gulfof Suez, Routh reef, Col. Dolfus, 29 December, 1928:oneF, 1.1 mm(MNHN-IU-2013-17321). Red Sea. Sudan. StnSAN46, Al Bahr al Ahmar. Sanganeb, 9 m, 25 March 1991: one ov. F, 2.6 mm( SMF). – StnSAN12, Al Bahr al Ahmar. Sanganeb, S-Jetty, E-Side, 2 m, 4 April 1991: six M, 1.6–2.0 mm, three ov. F, 1.6–2.4 mm, four F, 1.6–1.8 mm( SMF). – StnSAN3, Al Bahr al Ahmar. Sanganeb, N-Jetty, E-side, 1 m, 5 April 1991: seven M, 1.7–2.4 mm, four ov. F, 1.8–2.3 mm, five F, 1.6–1.8 mm( SMF). – StnSAN2, Al Bahr al Ahmar, Sanganeb, S-Jetty, W-side, 1 m, in Stylophora, 6 April 1991: four M, 1.5–2.0 mm, three ov. F, 1.8–2.0 mm, two F, 1.5–1.6 mm( SMF). – StnSAN8, Al Bahr al Ahmar. Sanganeb, S-Jetty, W-side, 1 m, 6 April 1991: four M, 1.5– 2.0mm, seven ov.F, 1.6–2.3 mm, two F, 2.0– 2.1 mm( SMF). – StnSAN13, Al Bahr al Ahmar. Sanganeb, N-Jetty, reefplateau, 1 m, 8 April 1991: three M, 1.7–2.0 mm, four ov. F, 2.1–2.5 mm, one F, 1.6 mm( SMF). – StnSAN25, Al Bahr al Ahmar. Sanganeb, 11 m, 8 April 1991: one M, 2.2 mm( SMF). – StnSAN28, Al Bahr al Ahmar, 9 April 1991: one ov. F, 2.1 mm( SMF). – StnSAN45, Al Bahr al Ahmar, 15 April 1991: three M, 2.2–2.5 mm, one ov. F, 2.5 mm, one F, 2.6 mm( SMF). – StnSAN167, Al Bahr al Ahmar. Port Sudan, Wingate Reef, 7 m, in living Pocilloporasp., 19 September 1992: one ov. F, 2.8 mm( SMF). – StnSAN115, Al Bahr al Ahmar. Sanganeb, 1 m, 26 September 1992: five M, 2.1–2.5 mm, two ov. F, 2.4–2.5 mm, two F, 2.1–2.2 mm( SMF). – StnSAN117, Al Bahr al Ahmar. Sanganeb, S-Jetty, 14 m, 27 September 1992: two F, 2.0– 2.1 mm( SMF). – StnSAN127, Al Bahr al Ahmar, 29 September 1992: one M, 2.0 mm, one ov. F, 2.1 mm( SMF). – StnSAN125, Al Bahr al Ahmar. Sanganeb, 14 m, 30 September 1992: one ov. F, 2.1 mm( SMF). – StnSAN129, Al Bahr al Ahmar. Sanganeb, N-Jetty, 1 m, 1 October 1992: one M, 2.2 mm( SMF). – StnSAN148, Al Bahr al Ahmar. Sanganeb, 22 m, 3 October 1992: one M, 2.0 mm, one ov. F, 1.8 mm( SMF). – StnSAN106, Al Bahr al Ahmar. Sanganeb, 6–10 m, 3 October 1993: one ov. F, 2.2 mm( SMF). – Rabigh, StnSAN1, coast guard, 7 April 2011: one M, 2.4 mm( SMF). Figure 4. Coralliogalathea humilis( Nobili, 1905), A, C–I, ovigerous female, 1.6 mm, Red Sea, Djibouti (UF33346). B, syntype, male 1.9 mm, Red Sea, Djibouti (MNHN-IU-2013-17324). A, B, carapace and abdomen, dorsal view. C, thoracic sternites 3 and 4. D, left part of cephalothorax, ventral view, showing antennular and antennal peduncles, and anterior part of pterygostomian flap. E, right Mxp3, lateral view; F, left P1, dorsal view. G, right P2, lateral view. H, right P3, lateral view. I, left P4, lateral view. Scale bar: 0.5 mm. Figure 5.A, Coralliogalathea humilis( Nobili, 1905), Saudi Arabia, ovigerous female, 2.1 mm, UF37156. B, Coralliogalathea humilis( Nobili, 1905)Saudi Arabia, ovigerous female, 2.0 mm, UF36158. C, Coralliogalathea joae sp. nov., Papua New Guinea, ovigerous female, 2.3 mm, MNHN-IU-2014-2383. D, Coralliogalathea megalochira(Nobili, 1906), French Polynesia, ovigerous female, 1.3 mm, UF15764. E, Coralliogalathea megalochira(Nobili, 1906), French Polynesia, male, 2.1 mm, UF15806. F, Coralliogalathea megalochira(Nobili, 1906), French Polynesia, male, 1.5 mm, UF23930. Red Sea. Jeddah, 21.88483°N, 38.9727°E, 0.5 m, 17 April 2011: four M, 1.5–2.0 mm, one ov. F, 1.6 mm( SMF). Madagascar. Tulear, coll. Thomassin, Stn 1666, two ov. F, 1.8–2.1 mm(MNHN-IU-2013-17317). – No Stn number: one juv., 1.0 mm (MNHN-IU-2013-17323), one ov. F, 2.0 mm (MNHN-IU-2013-17314). Description Carapace:1.1–1.3 times broader than long; cervical groove distinct, laterally bifurcated; most ridges on gastric region interrupted, with some scattered scale-like ridges; one scale-like epigastric ridge; two protogastric ridges, anterior ridge medially interrupted, posterior ridge short, arcuate, slightly prominent, with thick plumose setae; one mesogastric ridge, medially interrupted, not extending to anteriormost marginal branchial spines; one metagastric ridge, not medially interrupted and not extending to anterior branchial ridges. Anterior branchial region with distinct ridges. Mid-transverse ridge usually uninterrupted, preceded by shallow cervical groove, followed by three transverse ridges, two of them uninterrupted. Lateral margins slightly convex medially, with five or six spines: one spine in front of and four or five spines behind anterior cervical groove; first spine anterolateral, small, at level of orbit, located at midlength between outer orbital spine and anteriormost spine of branchial margin; two spines on anterior branchial margin, and two or three spines on posterior branchial margin; third spine, when present, very small. Strong outer orbital spine. Rostrum spatulate, horizontal, slightly longer than broad, length 0.4 and breadth 0.3 that of carapace; dorsal surface nearly horizontal in lateral view, concave at base; lateral margin with three incised sharp teeth; margin between proximal and median spines straight. Pterygostomian flap rugose, with one distinct spine on upper margin near linea anomurica, with sparse short setae, anterior margin bluntly angular. Sternum:Nearly as long as broad; lateral extremities gently divergent posteriorly. Third sternite triangular, 1.2 times wider than long. Abdomen:Somites 2–3 each with uninterrupted transverse ridge on tergite behind anterior ridge; somite 4 smooth or with minute setose scales on tergite; somites 5 and 6 smooth, posteromedian margin of somite 6 straight. Eyes:Ocular peduncles as long as broad, maximal corneal diameter 0.7 of rostrum width. Antennule:Article1 with two well-developed distodorsal and distolateral mucronated spines, distodorsal larger; one small distomesial spine and one minute distomesial spine on dorsal side. Ultimate article without a tuft of fine setae on distodorsal margin. Antenna:Article 1 with strong distomesial spine barely reaching distal margin of article 2. Mxp3:Ischium with spine on flexor distal margin; crista dentata with eight to ten denticles. Merus as long as ischium; flexor margin with one strong spine; extensor margin with one distal spine. Carpus unarmed. P1:Males 2.1–3.6 and females 1.6–2.1 times carapace length. Merus 0.7–0.8 length of carapace, 1.5–1.7 times as long as carpus, with some dorsomesial and a few ventromesial spines. Carpus 1.0–1.5 length of palm, 1.7–2.5 times as long as broad; dorsal surface with small spines; mesial row of spines, median spine strong. Palm 1.3–1.4 times as long as broad, unarmed. Fingers unarmed, 0.9–1.3 length of palm, each finger distally with two rows of teeth, spooned. P2–4:With setose striae and some long plumose setae. P2 1.8 times carapace length. Meri successively shorter posteriorly (P3 merus 0.8 length of P2 merus, P4 merus 0.9 length of P3 merus); P2 merus 0.5 carapace length, 3.2 times as long as broad, as long as P2 propodus; P3 merus 3.0 times as long as broad, as long as P3 propodus; P4 merus 2.7 times as long as broad, 0.9 length of P4 propodus. Extensor margins of meri with row of three or four proximally diminishing spines on P2–3, unarmed on P4; flexor margins distally ending in small spine followed proximally by several eminences; lateral sides unarmed. Carpi with no or one distal spine on extensor margin; lateral surface with several acute granules sub-paralleling extensor margin on P2–4; flexor distal margin with small spine. P2–4 propodi 4.0–5.8 times as long as broad; extensor margin unarmed; flexor margin with three or four slender, movable spines on P2–4. Dactyli distally ending in well-curved strong spine, length 0.6–0.7 that of propodi. Coloration:Base colour of carapace, abdomen and pereiopods light brown. Anterior half of abdomen sometimes with brown median longitudinal stripe. Most distal portion of pereiopod articles darker. Remarks
Coralliogalathea humilisis easily distinguished from C. tridentirostris( Miyake, 1953)from Japanby the shape of the rostrum, which is clearly wider (measured between the proximal spines) than long (measured between proximal spines and the tip of rostrum) in C. tridentirostris; in C. humilis, the rostrum is as long as, or longer than, it is wide. Furthermore, C. humiliscan be differentiated from C. megalochira, C. minutaand C. parvaby its absence of a transverse stria in the fourth abdominal somite, a third sternite that is wider than long and a metagastric ridge of the carapace that is usually uninterrupted. In the other three species, the fourth abdominal somite has a transverse stria behind the anterior ridge, the third sternite is longer than, or as long as, it is wide, and the metagastric ridge of the carapace is usually medially interrupted.
Based on molecular analyses, the most closely related species to C. humilisis C. minuta, with divergence values of 9.2% for COIand 2.4% for 16S. The greatest divergence observed was between C. humilisand C. tridentirostris(14.1 and 12.2% for COIand 16S, respectively). Average intraspecific distances in C. humiliswere 0.3 and 0.2% for COIand 16S, respectively ( Table 2). Distribution Red Sea, Madagascar, from 0.5 to 17 m, on stones and dead and living corals ( Stylophorasp., Acroporasp., Seriatoporasp.and Pocilloporasp.).
H. Coutiere
Djibouti
Djibouti
10
994
1
syntype
2013-03-04
UF
Saudi Arabia
4
19.0053
Saudi Arabia
7
40.1482
10
994
UF36151
1
2013-03-06
UF
Marca Is.
Saudi Arabia
10
18.2206
10
994
UF36158
1
2013-03-11
UF
Farasan Is.
Saudi Arabia
4
16.8359
7
42.3063
10
994
UF37026
1
2013-03-21
UF
Saudi Arabia
2
20.1672
7
40.2233
10
994
UF37156
1
2013-03-23
UF
Saudi Arabia
8
22.2044
51
39.047
10
994
UF37403
1
2013-09-27
UF
Saudi Arabia
10
27.6384
6
35.3062
10
994
UF36439
1
2013-09-29
UF
Saudi Arabia
8
28.4039
Gulf of Aqaba
6
34.7407
10
994
UF38080
1
2013-10-01
UF
Saudi Arabia
7
28.1846
6
34.6381
10
994
UF38193
1
2014-03-06
UF
Saudi Arabia
8
38.6163
6
22.7489
10
994
UF40269
1
2016-01-30
UF
Saudi Arabia
6
25.407
74
36.69
10
994
UF42374
1
2016-01-30
UF
Saudi Arabia
6
25.407
74
36.69
10
994
UF42390
1
Thomassin. Stn
Madagascar
Madagascar
10
994
4
2012-09-27
UF
Moucha Is.
Djibouti
12
11.6992
Djibouti
7
43.1432
10
994
UF33346
1
1991-03-25
SMF
Sudan
Red Sea.
9
Sanganeb
Stn
10
994
1
Al Bahr al Ahmar
1991-04-04
SMF
Sudan
2
Sanganeb
Stn
10
994
1
Al Bahr al Ahmar
1991-04-05
SMF
Sudan
1
Sanganeb
Stn
10
994
1
Al Bahr al Ahmar
1991-04-06
SMF
Sudan
1
Sanganeb
Stn
10
994
1
Al Bahr al Ahmar
1991-04-06
SMF
Sudan
1
Sanganeb
Stn
10
994
1
Al Bahr al Ahmar
1991-04-08
SMF
Sudan
1
Sanganeb
Stn
10
994
1
Al Bahr al Ahmar
1991-04-08
SMF
Sudan
11
11
995
Sanganeb
Stn
10
994
1
Al Bahr al Ahmar
1991-04-09
SMF
Sudan
Stn
11
995
1
Al Bahr al Ahmar
1991-04-15
SMF
Sudan
Stn
11
995
1
Al Bahr al Ahmar
1992-09-19
SMF
Sudan
Stn
7
12
996
Wingate Reef
Port
11
995
1
Al Bahr al Ahmar
1992-09-26
SMF
Sudan
1
Sanganeb
Stn
12
996
1
Al Bahr al Ahmar
1992-09-27
SMF
Sudan
14
Sanganeb
Stn
12
996
1
Al Bahr al Ahmar
1992-09-29
SMF
Sudan
Stn
12
996
1
Al Bahr al Ahmar
1992-09-30
SMF
Sudan
14
Sanganeb
Stn
12
996
1
Al Bahr al Ahmar
1992-10-01
SMF
Sudan
1
Sanganeb
Stn
12
996
1
Al Bahr al Ahmar
1992-10-03
SMF
Sudan
22
Sanganeb
Stn
13
997
1
Al Bahr al Ahmar
1993-10-03
SMF
Sudan
8
Sanganeb
Stn
13
997
1
Al Bahr al Ahmar
2011-04-07
SMF
Sudan
Stn
Rabigh
13
997
1
Al Bahr al Ahmar
2011-04-17
SMF
5
21.88483
Jeddah
5
38.9727
13
997
1
Al Bahr al Ahmar
Thomassin
Madagascar
Madagascar
13
997
1