Diagnosis: The modal fin-ray count of D-XX,10 A-II,19 and P-14 indicates Malacoctenus gilli and M. delalandii. Some M. aurolineatus can share this fin-ray count, but most have 11 soft dorsal-fin rays. Some M. erdmani share the median-fin ray count but have a mode of 16 pectoral-fin rays. L. kalisherae, L. bucciferus, and L. haitiensis can also overlap the fin-ray count. (DNA) Ecology: The dusky blenny is a somewhat common small blenny found primarily in shallow mixed habitats in bays. They have a curious, mostly island, distribution, found in the east from Bahamas and the Antilles down to offshore Venezuela and then in the west in Yucatan, Belize, and some offshore islands, but apparently not in Florida, Panama and the SW Caribbean or NE Venezuela. Their larvae are occasional in collections. Description: Pre-transitional larvae: Body long, narrow, and thin with a large round eye, pointed snout, and relatively small terminal mouth. Long continuous dorsal and anal fins with a short and narrow caudal peduncle. Pectoral fins long, reaching past the vent, and pelvic fins long and thread-like. The complement of melanophores on the top of the head is quite variable, with one to several larger melanophores overlying the midbrain lobes and sometimes additional smaller melanophores over the forebrain lobes (may be pseudo-larval: developing during transition, but look like larval melanophores). There is a cheek melanophore on each side. There are no melanophores along the base of the dorsal or caudal fins. Along the ventral midline there is notably no isthmus melanophore, but there is a deep melanophore behind the pelvic-fin base. Along the anal fin there is a melanophore at the base of each anal-fin soft ray (often not the last), followed by one or two melanophores along the ventral midline of the caudal peduncle. Internal melanophores comprise only the basic complement: the nuchal midline, otic capsule, and overlying the abdominal organs. Transitional stage: M. gilli larvae in transition first develop patches of small surface melanophores over the head, including a long bar down from the orbital rim at 5 o'clock and a broad eye-stripe from the orbital rim to the mid-maxilla. There are often several small pseudo-larval melanophores over the cranium in addition to the fine surface array. The fine melanophores on the pectoral-fin-base develop first as two small patches along the lower margin of the fleshy pectoral-fin base. Fine metamorphic melanophores later extend onto the body, forming complex patches and often arrays of small dark spots and a large dark spot forms on the first two dorsal-fin spine membranes. Multiple long cirri form on the nape, over the eye, and over the nasal tube. Juveniles: M. gilli juveniles have very distinctive markings, including a large black spot over the first two dorsal-fin spine membranes and an ocellated spot with a blue center over the rear spinous dorsal fin which extends well onto the body. Analogues: The variable occurrence of one to several large spots over the rear cranium and/or additional smaller spots forward overlaps the head pattern found on most other congeners. Reduced-complement M. gilli are the only Malacoctenus larvae that share the bare-forebrain-lobes pattern characteristic of M. macropus and M. erdmani. Fortunately, the anterior ventral midline series differs: M. gilli larvae have a deep pelvic-fin base melanophore but no isthmus melanophore while the remaining Malacoctenus have both (most species) or neither (M. macropus and M. erdmani). M. versicolor and M. triangulatus usually have more numerous head melanophores, often 10+ per side. M. versicolor and M. aurolineatus larvae also differ by having melanophores along the caudal-fin base. The D-XX,10 combination occurs in about two-thirds of M. gilli individuals, but is uncommon among congeners other than M. delalandii. M. boehlkei larvae have multiple head spots in alll quadrants, but have 33 dorsal-fin elements. Early transitional M. gilli larvae are distinguished by fin-ray counts, persistent larval melanophores, and their metamorphic melanophore pattern, i.e. the combination of the 5 o'clock bar of melanophores, an eye stripe to the mid-maxilla, and two patches of melanophores along the lower edge of the pectoral-fin base. M. triangulatus have a quite similar marking pattern at transition, but have a single central patch along the lower rim of the pectoral-fin base; M. macropus are also similar but have a stripe across the lower pectoral-fin base (and single cirri). Once recruits develop the large dark spot at the front of the dorsal fin and the characteristic ocellus on and below the rear spinous dorsal fin, they are easily distinguished from all other labrisomids.
Malacoctenus gilli, the dusky blenny, is a species of labrisomid blenny native to the Atlantic Ocean including the Gulf of Mexico and the Caribbean Sea from the Bahamas to the north coast of South America. This species inhabits reef patches, areas of sandy substrates with available rocks and beds of seagrass at depths of from 1 to 5 metres (3.3 to 16.4 ft). It can reach a length of 7.6 centimetres (3.0 in) TL.[2] The person honoured in the patronym of this species was not identified by Steindachner but it is most probably the American ichthyologist Theodore Nicholas Gill (1837-1914), the authority for the generic name Malacoctenus.[3]
Malacoctenus gilli, the dusky blenny, is a species of labrisomid blenny native to the Atlantic Ocean including the Gulf of Mexico and the Caribbean Sea from the Bahamas to the north coast of South America. This species inhabits reef patches, areas of sandy substrates with available rocks and beds of seagrass at depths of from 1 to 5 metres (3.3 to 16.4 ft). It can reach a length of 7.6 centimetres (3.0 in) TL. The person honoured in the patronym of this species was not identified by Steindachner but it is most probably the American ichthyologist Theodore Nicholas Gill (1837-1914), the authority for the generic name Malacoctenus.
