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Group 2: six-spined shortfin gobies 2
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Group 3: seven-spined shortfin gobies
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Group 4: longfin gobies
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Group 5: divided pelvic-fin gobies
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allied family Ptereleotridae
allied family Eleotridae
allied family Microdesmidae

Group 1: The short-fin gobies pt. 1 (six-spined, fused)

Bathygobius, Lophogobius, Priolepis, Awaous, and Sicydium

 

This group of six-spined gobies with short median fins and fused pelvic fins includes several unrelated genera of gobies, including tidepool, reef, and fresh-water species. Although common in their appropriate habitats, this group of gobies are not usually observed or photographed on reefs. The abundant reef and sand gobies of Coryphopterus and Lythrypnus are separated for convenience and treated in Group 2.

Note: Fin-ray counts for the second dorsal fin and the anal fin are total elements (spines plus rays) and species are listed in rough order of increasing fin-ray counts.
Bathygobius curacao
 

Diagnosis: Modal fin-ray counts of D-VI,10 A-9 and Pect-15-17 with fused pelvic fins indicate Bathygobius curacao and Lythrypnus (and overlaps the range of Coryphopterus alloides). These genera typically have one fewer anal-fin ray than second-dorsal-fin rays. Larval Lythrypnus are lightly-marked and develop radiating bars of melanophores around the eye at transition. Coryphopterus also have lightly-marked larvae and C. alloides is the only species which would overlap this fin-ray count, although only rarely with 15 pectoral-fin rays. Lophogobius cyprinoides and Priolepis hipoliti share the median-fin ray count but have more pectoral-fin rays. Bathygobius are known for having the dorsal-most pectoral-fin rays separate from the rest and filamentous, however this feature is not apparent on larvae. This larval type has 15-17 pectoral-fin rays, indicating the species is B. curacao (B. soporator and B. mystacium have a mode of 19-20 pectoral-fin rays). (DNA) G14a

Analogues: (heavy ventral markings)
Description: Body relatively thin, long and narrow with a large eye and a terminal large mouth. Pectoral fins long, reaching to vent. Pelvic fins long, reaching almost to the vent, with an obvious pelvic frenum. Dorsal and anal-fin bases medium-length and caudal peduncle medium-length and sharply narrowing, 7-9 procurrent caudal-fin rays (7-8 spindly). Heavily marked; along the ventral midline there are large point, stellate, or streak melanophores at the isthmus, one or two forward of the pelvic-fin insertion, and a few behind the pelvic-fin insertion along the abdominal midline. Then there is a variable row of two or three large paired melanophores spaced along the anal-fin base, continuing as a row of three or four large single melanophores along the caudal peduncle ending at the start of the procurrent caudal-fin rays (the anal-fin base and caudal peduncle melanophores often merge into a single long streak). Dorsal markings consist of a row of paired melanophores on either side of the dorsal midline: a pair just forward of the spinous dorsal fin, one just behind, then two or three pairs spaced along the soft dorsal fin, followed by one to three unpaired melanophores along the dorsal midline of the caudal peduncle ending well before the start of the upper procurrent caudal-fin rays. Markings on the head consist of a large melanophore outlining the lower edge of the dentary at the tip of the lower jaw and another at the angle of the jaw (on pre-transitional larvae). Internal melanophores are present at the base of the braincase (sometimes around the upper braincase as well), at the sacculus, along the dorsal surface of the peritoneum and swim bladder, and continuing along the gut to the vent (often all of these merge into a dark streak arcing through the body). There is a row of internal vertebral melanophores above and usually below the vertebral bodies from the mid-body to the caudal peduncle. This streak can be prominent or mostly obscured by overlying musculature. Some individuals have melanophores at the base of the lower segmented caudal-fin rays extending out a short distance along the rays. Series of transitional larvae show development of the eye from round with dorsal and ventral indentations in the iris (mostly on the dorsal-anterior to ventral-posterior axis, but can vary) to fully round (most pre-transitional larvae captured have no indentations, and some transitional larvae have iris indentations). Transitional larvae intensify the surface melanophores on the iris (covering the upper third of the eyeball and at 2, 5 and 7-8 o'clock) and develop a stripe from the eye forward across the mid-upper jaw to the mid-lower jaw and a stripe of melanophores behind the eye across the mid-operculum. Transitional larvae then develop a speckling of large melanophores and leukophores on the top of the head to the base of the pectoral fin and a stripe of iridophores across the operculum and onto the base of the pectoral fin.
   
Bathygobius curacao larva
5.2 mm SL
melanophores in streaks
San Blas, Panama, SB86-426
 
bathygobius curacao (coral reef fish larvae)
 
Bathygobius curacao larva
6.8 mm SL
San Blas, Panama, SB87-225
 
 
 
 
Bathygobius curacao larvae
4.7 and 5.9 mm SL
smallest larva above, size comparison
San Blas, Panama, SB86-1010
 
Bathygobius curacao transitional larva
5.5 mm SL
with iris indentations
San Blas, Panama, SB87-219
 
Bathygobius curacao transitional larvae
5.3 and 4.9 mm SL
internal melanophores
San Blas, Panama, SB86-1123
 
Bathygobius curacao transitional series
5.3, 5.4, and 5.9 mm SL
San Blas, Panama, SB86-426
 
Bathygobius curacao transitional larva
6.0 mm SL
note head neuromasts
San Blas, Panama, SB86-1010
 
 
 
Bathygobius mystacium
 

Diagnosis: Modal fin-ray counts of D-VI,10 A-9 and Pect-19 with fused pelvic fins indicate Bathygobius mystacium or B. soporator. The two species are usually separated by the former having 35 (33-36) and the latter 37-41 scale rows later in development. The genus is known for having the dorsal-most pectoral-fin rays separate from the rest and filamentous, however this feature is not apparent on larvae. This larval type has a mode of 19 pectoral-fin rays, consistent with either B. soporator or B. mystacium. Since DNA sequences match the "spot" type Bathygobius larva to B. soporator, this larval type matches B. mystacium. Other six-dorsal-spined gobies with the same median-fin ray counts (but fewer pectoral-fin rays) include the congener B. curacao with 16-17, as well as Lythrypnus (14-16), Coryphopterus alloides (16-17), Lophogobius cyprinoides (17-18), and Priolepis hipoliti (18). (ML) G14b

Analogues: (heavy ventral markings)
Description: Body relatively thin, long and narrow with a large eye and a terminal mouth. Pectoral fins long, reaching to the vent. Pelvic fins long, reaching almost to the vent, with an obvious pelvic frenum. Dorsal and anal-fin bases medium-length and caudal peduncle medium-length and sharply narrowing, 7-9 procurrent caudal-fin rays (7-8 spindly). Heavily marked mostly along the lower and midbody with markedly dendritic melanophores: there is a large melanophore at the tip of the lower jaw and at the angle of the jaw. Along the ventral midline there are large stellate or streak melanophores at the isthmus, forward and behind of the pelvic-fin insertion, then a variable row (paired, one per side) at the anal-fin base and then unpaired extending along the caudal peduncle ending at the start of the procurrent caudal-fin rays. Internal melanophores occur around the lower brain case and around the sacculus continuing along the dorsal surface of the peritoneum and swim bladder extending to the gut near the vent (often all of these merge into a dark streak arcing through the body). There is a row of internal melanophores surrounding the vertebral bodies and extending for most of the spine from the level of the vent to the mid-caudal peduncle, often with a discrete row of deep melanophores along the dorsal vertebral spines as well. There is a prominent and characteristic matching row of dendritic surface melanophores along the lateral midline. Melanophores along the dorsal midline are limited to the rear body (vs. B. curacao ), as two or three variably-paired large stellate melanophores on either side of the dorsal midline at the base of the mid to rear soft dorsal fin. Series of transitional larvae show development of the eye from round with dorsal and ventral indentations in the iris (mostly on the dorsal-anterior to ventral-posterior axis, but can vary) to fully round (most pre-transitional larvae captured have no indentations, and some transitional larvae have iris indentations).with melanophores extending in patches across the surface of the iris. Transitional larvae develop a stripe of melanophores from the eye forward to the mid-upper jaw and across to the mid-lower jaw. As transition continues, the melanophores become essentially a stripe from the tip of the lower jaw back across the mid-upper jaw to the eye, over the iris, continuing internally over the base of the braincase to the sacculus continuing internally to the dorsal surface of the swim bladder then to the vertebral row of melanophores. A branch stripe extends bilaterally along the internal lateral abdominal wall to the vent and along the base of the anal fin to the tail. A scattering of large melanophores and some leukophores develops on the top of the head.
   
Bathygobius mystacium larva
5.9 mm SL
San Blas, Panama, SB86-425
 
 
 
Bathygobius mystacium larva
5.7 mm SL
San Blas, Panama, SB86-808
 
 
Bathygobius mystacium larva
5.9 mm SL
with iris indentations
San Blas, Panama, SB87-218
 
Bathygobius mystacium larva
5.3 mm SL
internal melanophores
San Blas, Panama, SB84-523
 
Bathygobius mystacium transitional larva
6.3 mm SL
internal melanophores
San Blas, Panama, SB87-219
 
Bathygobius mystacium transitional larva
5.8 mm SL
San Blas, Panama, SB86-808
 
Bathygobius mystacium transitional larva
5.9 mm SL
San Blas, Panama, SB86-1008
 
 
 
Bathygobius soporator
 

Diagnosis: Modal fin-ray counts of D-VI,10 A-9 and Pect-19 with fused pelvic fins indicate Bathygobius soporator or B. mystacium. The two species are usually separated by the former having 37-41 and the latter 35 (33-36) scale rows later in development. The genus is known for having the dorsal-most pectoral-fin rays separate from the rest and filamentous, however this feature is clearly not apparent on larvae. The DNA sequence of this larval type (the "spot" type, i.e. a single large vertebral melanophore) matches adult B. soporator. Other six-dorsal-spined gobies with the same median-fin ray counts (but fewer pectoral-fin rays) include the congener B. curacao with 16-17, as well as Lythrypnus (14-16), Coryphopterus alloides (16-17), Lophogobius cyprinoides (17-18), and Priolepis hipoliti (18). (DNA) G14

Analogues: (heavy ventral markings)
Description: Body relatively thin, long and narrow with a large eye and a terminal mouth. Pectoral and pelvic fins long, reaching almost to the vent, with a obvious pelvic frenum. Dorsal and anal-fin bases medium-length and caudal peduncle medium-length and sharply narrowing, 7-9 procurrent caudal-fin rays (7-8 spindly). Heavily marked mostly along the lower and midbody: there is a large melanophore at the tip of the lower jaw and one at the angle of the jaw. Along the ventral midline there are large stellate or streak melanophores at the isthmus, the pelvic-fin insertion, and one to three along the mid-abdomen, then variably paired on either side of the ventral midline at the anal-fin base and then extending along the ventral peduncle ending at the start of the procurrent caudal-fin rays. Internal melanophores occur around the sacculus and along the dorsal surface of the swim bladder and around the gut near the vent. Melanophores along the dorsal midline are limited to the rear body (vs. B. curacao); as one to three variably paired large stellate melanophores on either side of the dorsal midline at the base of the mid to rear soft dorsal fin. Long streak melanophores are present along the membranes of the second to fifth fin rays on both the soft dorsal and anal fins. There is a single prominent stellate internal vertebral melanophore at the lateral midline at about the level of the mid soft dorsal fin that ramifies around the vertebral bodies and extends between and around myomeres and often up to the surface. Series of transitional larvae show development of the eye from round with dorsal and ventral indentations in the iris (mostly on the dorsal-anterior to ventral-posterior axis, but can vary) to fully round (most pre-transitional larvae captured have no indentations and some transitional larvae have iris indentations). Early transitional larvae develop a stripe of melanophores from the eye forward to the mid-upper jaw. As transition continues, the melanophores become essentially a stripe from the tip of the lower jaw across the mid-upper jaw to the eye, over the iris and onto the operculum, continuing internally from the sacculus to the dorsal surface of the swim bladder and around the gut near the vent and along the anal fin to the tail. Melanophores also develop at the end of the caudal peduncle, primarily at the base of the central and lower segmented caudal-fin rays. Series of transitional larvae show the eye remaining round, but becoming larger with the iris developing a dark surface pigmentation layer. Late transitional larvae develop an additional scattering of large discrete melanophores on the dorsal half of the head and the operculum, extending to the base of the pectoral fin. Small iridophores occur in patches behind the eye and in a stripe out onto the middle rays of the pectoral fin. Patches of small melanophores develop around the base of the spinous dorsal fin.
   
Bathygobius soporator larva
5.5 mm SL
San Blas, Panama, SB86-425
 
 
Bathygobius soporator larva
5.6 mm SL
single branching vertebral melanophore
San Blas, Panama, SB86-425
 
Bathygobius soporator larva
5.7 mm SL
with iris indentations
San Blas, Panama, SB87-218
 
Bathygobius soporator early transitional
6.0 mm SL
San Blas, Panama, SB86-425
 
 
 
Bathygobius soporator transitional larva
5.6 mm SL
note pelvic-fin frenum
San Blas, Panama, SB86-616
 
 
Bathygobius soporator transitional larva
5.8 mm SL
San Blas, Panama, SB86-426
 
 
Bathygobius soporator transitional recruit
7.4 mm SL
larval melanophore remnants
on dorsal and anal-fin ray membranes
Noronha, Brazil FN01
 
 
Lophogobius cyprinoides
Diagnosis: Modal fin-ray counts of D-VI,10 A-9 and Pect-18 are shared by Lophogobius cyprinoides and Priolepis hipoliti. L. cyprinoides has a pelvic frenum, which is absent in larval and juvenile P. hipoliti. Coryphopterus alloides matches the median-fin ray counts but has fewer pectoral-fin rays (16-17) and recruits are pale sand gobies with a prominent internal dark mid-body bar. Bathygobius mystacium and B. soporator have more pectoral-fin rays (mode of 19-20). B. curacao and Lythrypnus have fewer pectoral-fin rays (15-17 and 14-16).
Analogues: (VMS4: jaw angle, thorax, anal fin, caudal peduncle) The larval stage has not been identified for Lophogobius cyprinoides, however, based on the transitional recruit, the melanophore pattern would be similar to the Bathygobius, Lythrypnus, and Coryphopterus larval types. Unfortunately, the latter taxa are very common and diverse in larval collections, making it possible that the larvae of L. cyprinoides may have been subsumed in those. Fin-ray counts do differ, but only slightly. Notably, if it is consistent, the absence of a second thoracic melanophore anterior to the pelvic-fin insertion would be important since these other larval types have two thoracic midline melanophores. Bathygobius larvae have either fewer or more pectoral-fin rays and distinctive internal melanophores not obviously apparent on the transitional L. cyprinoides. Larval Coryphopterus only rarely have 10/9 median fin elements; the one species with that count, C. alloides, has fewer pectoral-fin rays and more procurrent caudal-fin rays. Lythrypnus have fewer pectoral-fin rays. The seven-spined gobies with similar larvae do not have the jaw angle melanophores and the caudal peduncle streak extends only halfway to the caudal fin. The seven-spined Barbulifer larvae share the median fin-ray count and the jaw angle melanophores, but have additional melanophores and a flattened head.
Description: Based on the transitional recruit, the body is somewhat long and narrow (although wider anteriorly than most goby larvae) with a large eye and a terminal mouth. Pectoral fins long, pelvic fins long and fused with an obvious pelvic frenum, caudal-fin procurrent rays 6-7 (6 spindly). Dorsal and anal-fin bases relatively short, caudal peduncle rapidly narrowing. Larval melanophores apparent on the transitional recruit include those at the jaw angle and a series along the ventral midline: a single one at the thorax, a row along the base of the anal-fin rays, and streaks along the caudal peduncle extending up to the procurrent caudal-fin rays.
Lophogobius cyprinoides
transitional recruit
7.4 mm SL
Colon, Panama, N7527b
caribbean fish larvae
  caribbean fish larvae
Lophogobius cyprinoides recruit
9.3 mm SL
Colon, Panama, N7527b
caribbean fish larvae
  caribbean fish larvae
   
Priolepis hipoliti
Diagnosis: Modal fin-ray counts of D-VI,10 A-9 and Pect-18 indicate Priolepis hipoliti and Lophogobius cyprinoides. P. hipoliti larvae and juveniles are missing the pelvic frenum, present on L. cyprinoides and most other gobies. Priolepis robinsi from Colombia and the Brazilian P. dawsoni have higher median-fin ray counts (D-VI,11 A-10). Coryphopterus alloides match the median-fin ray counts but have fewer pectoral-fin rays (16-17) and recruits have a prominent internal dark mid-body bar. Coryphopterus kuna has 9/9 and pect. 15. Bathygobius mystacium and B. soporator have more pectoral-fin rays (mode of 19-20). B. curacao and Lythrypnus have fewer pectoral-fin rays (15-17 and 14-16). (DNA)
Analogues:
Description: Body long and narrow with a large eye and a terminal large mouth. Pectoral fins long, pelvic fins long and fused with clearly no pelvic frenum. Dorsal and anal-fin bases relatively short, caudal peduncle long and rapidly narrowing. The first dorsal and anal-fin rays are long and the last short, making a somewhat triangular fin shape. Series of transitional larvae show the eye remains round but the head thickens and the body hunches over. Transitional larvae develop melanophores in bars below the eye and an arc across the top of the head behind the eye and down the preopercle. Sensory papillae develop in rows on the head. Transitional recruits show a pattern of dark median fins and bars on the head and body.
Priolepis hipoliti transitional larva
9.8 mm SL, DNA confirmed ID
Belize, BCN52, coll. by C. Nolan
priolepis hipoliti
 
 
 
Priolepis dawsoni recruit
10.1 mm SL
Noronha, Brazil, FN01
 
   
Awaous banana
 
Diagnosis: Long thin larvae with a modal fin-ray count of D-VI,11 A-11 Pect-16 indicates the river goby Awaous banana. Coryphopterus personatus shares the fin-ray counts but their larvae are very different; they are smaller and shorter and have typical ventral midline melanophore rows and no large internal melanophores. A. flavus from Colombia to Brazil has a modal fin-ray count of D-VI,10 A-10 Pect-16.
Analogues: Compared to other long thin goby larvae, Awaous and Sicydium larvae have shorter dorsal and anal fins and many more procurrent caudal-fin rays. The gobioid sleeper family, the eleotrids, share these two attributes, but have clearly-divided pelvic fins and lack the large internal melanophore over the rear end of the anal fin. The larvae of Sicydium are quite similar to Awaous banana in form, markings, and median-fin ray counts. The primary meristic difference is higher pectoral fin-ray counts in larval Sicydium (20 or more). Both sets of larvae share the large internal melanophore over the anal fin, but Sicydium larvae have additional melanophores, in particular at the base of the upper caudal fin, deep to the pectoral-fin base, and along the mid-abdominal ventral midline. In addition, the large internal melanophore in larval Sicydium has characteristic, sometimes extreme, long filamentous extensions.
Description: Body thin, long, and narrow with a medium-sized round eye and a terminal small mouth. Pectoral fins very short, pelvic fins very short. Dorsal and anal-fin bases short and caudal peduncle sharply narrowing, 10-14 procurrent caudal-fin rays. Melanophores on the head only along the dorsal edge of the anterior premaxilla on each side and midline near the tip of the lower jaw. Ventral melanophores are limited to a paired large melanophore at the mid-base of the anal fin and internal melanophores overlying the posterior swim bladder and extending down to the vent. A large deep internal vertical melanophore underlies the last anal-fin ray extending up to the lateral midline.
Awaous banana larva
12.3 mm SL, DNA confirmed ID
Yucatan, Mexico, 240306
coll. by Lourdes Vasquez et al.
caribbean fish larvae
  caribbean fish larvae
  caribbean fish larvae
  caribbean fish larvae
   
Sicydium altum
 
Diagnosis: Long thin larvae with a short round pelvic-fin sucking disk and modal fin-ray counts of D-VI,11 A-11 Pect-20 indicate the river gobies of Sicydium. The taxonomy and range of species in this genus are generally unresolved and numerous species have been described. I follow the recent review for Central America by Lyons (2005). He indicates that S. altum ranges along the coast from Costa Rica through Panama to Colombia, while S. adelum is localized to Costa Rica and S. plumieri and S. punctatum occur in the far east of Panama near Colombia and probably beyond. The remaining Central American species is the northern Sicydium gymnogaster, found only from Veracruz, Mexico to Honduras. There are many other named Caribbean species, some with very restricted ranges, including S. vincente (West Indies), S. caguitae (Puerto Rico), S. montanum (Venezuela), S. buscki and S. gilberti (both Dominican Republic), while S. antillarum is considered widespread.
Analogues:
Description: Body thin, long, and narrow with a medium-sized round eye and a terminal small mouth. Pectoral fins very short, pelvic fins very short. Dorsal and anal-fin bases short and caudal peduncle long and narrowing, 10-14 procurrent caudal-fin rays (this large number shared only with some of the eleotrids).
Immature larvae long and thin with Melanophores on the head only along the dorsal edge of the front premaxilla on each side and one midline below the dentary at the tip of the lower jaw. There are ventral midline Internal melanophores are present at the dorsal surface of the swim bladder and around the gut near the vent. melanophores at the base of the upper segmented caudal-fin rays (an unusual pattern for gobiid larvae). There is a large and characteristic internal melanophore at the mid-body above the anal fin that extends in long dendritic filaments up to the surface and along the skin (usually towards the head).
Mature larvae are large and stout with a rounded cross-section. The pelvic fins are very short and rounded with an obvious frenum. Mature larvae retain the melanophore patterns of immature larvae, but the melanophores along the ventral midline are present at the pelvic-fin insertion and behind the pelvic-fin insertion, followed by a short row of melanophores along the lateral wall of the abdomen on each side. There is a row of melanophores along the anal-fin base (variably paired, one per side, more than one per fin ray) and then extending unpaired along the ventral midline of the caudal peduncle ending near the start of the procurrent caudal-fin rays. The melanophores at the base of the upper segmented caudal-fin rays persist and the large internal melanophore remains prominent.
Sicydium altum larva
25.7 mm SL
San Blas, Panama, SB80-101
sicydium altum
 
Sicydium altum larva
23.2 mm SL
San Blas, Panama, SB86-702
Sicydium altum larva
23.8 mm SL
San Blas, Panama, SB80-101
Sicydium altum larvae
23.8 mm SL (above) 25.7 mm SL (below)
San Blas, Panama, SB80-101
 
Sicydium altum larvae
23.8 mm SL (above) 25.7 mm SL (below)
San Blas, Panama, SB80-101
   
Sicydium gymnogaster/plumieri
Diagnosis: Long thin larvae with a short round pelvic-fin sucking disk and modal fin-ray counts of D-VI,11 A-11 Pect-20 indicate the river gobies of Sicydium. The taxonomy and range of species in this genus are generally unresolved and numerous species have been described (Bussing 1995). According to Lyons (2005) the northern Central American coastal species is S. gymnogaster, found from Veracruz, Mexico to Honduras, but this Yucatan-caught larvae is a DNA match to an adult from St. Thomas USVI, indicating that the species limits and/or phylogenetics are in question.
Analogues:

Description: Body thin, long, and narrow with a medium-sized round eye and a terminal small mouth. Pectoral fins very short, pelvic fins very short. Dorsal and anal-fin bases short and caudal peduncle narrowing, 10-14 procurrent caudal-fin rays. On the head there are melanophores lining the premaxilla and the dentary at the tip of the lower jaw and a pair of large melanophores at the rear edge of the brain case. A large sub-surface melanophore is placed behind the pectoral-fin base on each side of the body. Along the ventral midline there is a large melanophore at the mid-abdomen and then paired at the base of the mid-anal-fin. Internal melanophores overlie the posterior swim bladder and extend down to the vent. A large deep internal vertical melanophore underlies the last anal-fin ray extending to the lateral midline, where it surfaces and spreads as a large dendritic surface melanophore with characteristically long filamentous extensions. Melanophores are concentrated at the base of the mid and upper caudal-fin segmented rays.

Sicydium gymnogaster larva
11.8 mm SL, DNA confirmed ID
Yucatan, Mexico, 200306
coll. by Lourdes Vasquez et al.
sicydium altum
  sicydium altum
  sicydium altum
   
   

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