The family Acanthuridae boasts of charismatic, charming and iconic reef fishes that are immediately recognizable both in the field and in the trade. All eighty or so species spanning the six various genera have a single unifying trait, and that is the possession of razor sharp caudal peduncular spines. The family is diverse and well represented across all major oceans, spanning a cosmopolitan distribution wherever suitable habitat is provided.
In accordance to the family’s diversity, Acanthuridae are unsurprisingly heterogeneous in their form, with different genera or species groups adopting their own characteristic charm. The genusCtenochaetus例如，铰接的下巴与Acanthurus。NasoandPrionurushave unretractable caudal scalpels, and members of斑马瘤are well known for their elongated rostrum and sail like median fins. AlthoughAcanthurusby far and large remains to be the most populous and cosmopolitan genus, it is斑马瘤that proves to be the blue eyed boy of the family. Like thenigricansgroup complex在属中Acanthurus,斑马瘤will be receiving the same treatment, and in this article we discuss the speciation, biogeography and hybridization of this well loved genus.
The seven species of斑马瘤(Z. scopas,Z. flavescens,Z. Xanthurum,Z. Gemmatum,Z. veliferum,Z. desjardiniiandZ. rostratum) form a monophyletic group, with various members within forming their own cladistic distinctions. It has been hypothesized by Guiasu and Winterbottom thatZ. veliferum(and subsequentlyZ. desjardinii）是第一个脱离的物种斑马瘤血统，其次是Z. Gemmatum。其余物种形成单系进化枝，其中Z. rostratum要么是姐妹团体Z. Xanthurum, or the sister species toZ. scopasandZ. flavescens。
We feel thatZ. rostratum(with its unusually long snout and silver-streaked dorsum) is perhaps best left as a basal branch for the remaining four species, in whichZ. Gemmatum与Z. Xanthurum, andZ. scopas和Z. flacescens。This may be a little contentious compared to the published phylogeny hypothesised by Guiasu and Winterbottom, but the biogeography of bothZ. GemmatumandZ. Xanthurum（以及在体内具有黄色尾鳍和斑点的两个物种）可能比前面提到的更紧密的关系。广泛的地理重叠Z. rostratum和Z. scopas也表明他们的异同in cladistics, seeing as sister species are unlikely to be so widely sympatric. Again, these are just casual observations from a different perspective, and seeing as any number of varying characteristics can be used in consideration for a phylogenetic analysis, we might very well be wrong.
Phylogenetics aside, the genus斑马瘤已经进化出了某些特征，使它们与阿斯河岛的其余部分区分开来。一方面，所有成员看起来都比宽阔，具有非常独特的帆式背鳍和肛门鳍。这些在其少年形式中尤为明显，在这种形式中，它们看起来非常不成比例。当少年到达成人兜帽时，他们的身体伸长弥补了帆的高度，鱼的延伸更加同质。它们的音阶被拉长和尖锐，末端放置的嘴衬有小牙齿，适合在丝状藻类上采摘。在至少一个物种中，此特征是高度突出和诊断性的，借用其特定词的使用“rostratum” to be very appropriate.
它们的单一可伸缩花梗刺夹在薄鞘中，至少有四种（Z. scopas,Z. flavescens, Z. xanthurumandZ. rostratum），一块细刚毛（硬毛）是该脊柱的前面，如凸起的椭圆形标记。有人提出，这种刚毛的存在与性别联系在一起，仅在大型男性中出现，是性二态性状。但是，对于这种奇怪的形态特征及其所提供的功能或所有物种是否拥有的功能尚不清楚，尚不清楚。
叶骨粘膜膜is the most recognisable of the genus, and is the only one of two striped members. The species is hazelnut to chocolate, with five custard stripes running parallel along the body (reminiscent of a giant kinder bueno). The face is heavily spotted in large adults, and the caudal fin is yellow with a white perimeter. The darker body coloration between the bars are striated in orange which breaks into shorter dashes and spots nearing each terminal end.
少年用坚固的黄色泛音器洗涤，棒（除了面部的棒）高度扩散且模糊不清。像许多人一样斑马瘤,Z. veliferum在其少年阶段的高度不成比例，但是身体随着年龄的增长而延长，以补偿其中位鳍的高度。Z. veliferumis widespread in the Pacific Ocean, and can be found in Vietnam eastward to the Pitcairn group, Hawaiian Islands, northward to southern Japan, southward to Rottnest Is., and New South Wales, Australia and Rapa, French Polynesia except the Marquesas. It is most often collected out of Indonesia and the Philippines.Z. veliferumstrays to the Christmas Islands, where it is at its Indian Ocean limit. In the rest of the Indian Ocean, this species is replaced by its allopatric geminate sister,Z. desjardinii。This species is likely to hybridize withZ. desjardiniiin the overlapping region of the Christmas Islands.
The Indian Ocean representative of the striped斑马瘤clade isZ. desjardinii。This species is highly similar to its Pacific Ocean counterpart, and is most easily discerned only in its adult form.Z. desjardinii是黑巧克力棕色，奶油色条纹仅限于脸部，否则会发现它。而不是典型的奶油条纹，而是Z. desjardiniiis marked with a series of vertical orange stripes which run parallel along the body. The ventral region is heavily spotted in the same orange, and a series of fine striations trace the dorsal and anal fins in concentric semicircles. The caudal fin is black and spotted in white, and this serves as the most reliable distinction between the two sisters.
少年和年轻人采用更典型的绒毛外观，并在通常的蛋ust条纹中装饰。然而，中间的鳍片与成年人一样严重地网状橙色，随着年龄的增长，酒吧消失了。Z. desjardiniiis found in the Red Sea, south to Natal, South Africa and east to India, Java and the Cocos-Keeling Islands. In the Pacific Ocean and the Christmas Islands it is replaced byZ. veliferum. Z. desjardinii通常是出口啊f the Red Sea. This species is likely to hybridize withZ. veliferumin the overlapping region of the Christmas Islands. Together,Z. veliferumandZ. desjardiniirepresents the “striped clade” of the斑马瘤group.
在吉亚和温特博特的插图中，斑马瘤gemmatumstands alone in the monophyletic group, unpaired with any other species. The spotted appearance is a rather unique trait for this genus, withZ. Xanthurumbeing the only other species to show a trace amount of this characteristic on its head. InZ. Gemmatum，身体着色是沥青灰色到黑曜石，面部区域是更轻，更栗子的棕色。在胸鳍上方的Operculum后面，有一对辉煌的，几乎是胶状的条纹。身体和中间的鳍在白色或最淡淡的爱丽丝蓝色阴影中被大量发现，并且在完全生长的标本中，它们可能会结合并重新调整以形成一系列弱小的条纹。尾鳍是黄色的，也被发现。
Z. Gemmatum仅限于印度洋,可以吗found in Mauritius to Madagascar and Natal, South Africa. It has also been recorded from Mozambique. This species is often encountered singly, and never in any great amount. The geographical proximity of this species in relation to斑马瘤黄色, and the minor phenotypic similarities of the two may suggest a cladistic relationship, as seen in our hypothesized phylogenetic tree.Z. Gemmatum通常是出口啊f Madagascar and Mauritius. It is rare in the trade and is regarded as the most prized and expensive of the surgeonfishes, although I find this to be remarkably unjust. It hybridizes withZ. scopasthroughout its range.
The love child between the two species isn’t quite as dramatic as you’d expect, seeing as both parents are dark colored in nature. The influence ofscopas但是，DNA弄乱了现场模式gemmatum，所产生的杂种在其设计中失去了均匀性。中间的鳍片被斑点发现，尾鳍采用透明而不是黄色。尽管其稀有性和富裕的价格标签，这种混合动力车却微不足道且令人印象深刻，并且使Shine Shine to to to the GeedigreeZ。gemmatum。
尽管Z。黄色is more accurately a deep inky cobalt with a purple slate best seen under a side light. A constellation of spots and reticulated markings cover the face and a series of innocuous stripes run parallel horizontally across the body. The pectoral fins and tail are coloured in a rich yellow, and ironically it is this feature which earns the species its name黄色。Juveniles are coloured the same.斑马瘤黄色该属的地理范围最严格，严格发现在红海和波斯湾。有时在马尔代夫中记录了流浪，尽管很少。
畸变Z. Xanthurumoccur very rarely, and is nowhere near as common as those seen in Z. scopas or Z. flavescens. Rare individuals such as the ones above sporting fully purple bodies and piebald patterns have been documented, but the homogeneity of this species is rather strongly represented.Z. Xanthurumis mostly solitary or found in small groups in the wild, and is sometimes found in the company ofZebrasoma desjardinii。尽管具有狂野的行为，但该物种仍然是业余爱好最受欢迎的阿斯塔氏菌之一。该物种尚不知道会形成任何杂种。
斑马瘤rostratumis morphologically peculiar with its highly pronounced rostrum. This species ranges in color from jet to liquorice black, but in adults, a greenish tinge may invade the face and intramembranous spaces along the dorsal and anal fins. Sub-adults and adults may develop a silvery-glacous streak that traces the dorsal fin base, starting at the nape and ending at the peduncular base. A patch of setae can be seen in very large specimens, and this presents itself as a raised, oval patch just anterior of the peduncular spine. It has been suggested that this is a sexually dimorphic trait only present in males, but not much is known about this unique trait.Z. scopas,Z. XanthurumandZ. flavescensalso possess this peduncular setae, although it may not be apparent in photos.
少年完全是黑色的，除了白色的尾梗脊柱外壳。同样，就像斑马瘤一样，少年更加显着“帆船”，但这种不成比例的人成年。Z. rostratumranges across the central Pacific from Tuvalu to Pitcairn including all of French Polynesia, north to the Line Islands and south to Rapa. A single waif was found in Oahu, Hawaii.Z. rostratum在整个地理分布中并不罕见，并且出现单独发生。它的稀有性也转化为水族馆行业，在那里获得了很高的收益。该物种通常是从圣诞岛Kiritimati收集的。它与之杂交Z. scopasthroughout its range.
As withZ. GemmatumxZ. scopas，合并Z. scopasDNA withZ. rostratumserves to nullify much of the jet black qualities of the former. Hybrids are often dark grey-granite with a lightening of the facial region. The most discerning characteristic is the presence of very fine striae in the form of meandering squiggles on the body. This is a characteristic seen inZ. scopas，但在没有特色的情况下不存在Z. rostratum。看到Z. rostratum在整个范围内并不罕见Z. scopas是瘟疫，杂种有时比血统更常见Z. rostratum，作为前一个物种，每当机会出现时都像恶魔鼬鼠一样。这个Lovechild比Z. rostratum。
斑马瘤scopasis literally one of the most widely distributed reef fishes and can be found in nearly all suitable habitats in the Pacific and Indian Ocean. Its distribution map is featured at the start of this article, and the species can be viewed as the piscine version of the common household rodent. This species is uniformly muted brown with a series of very fine spots on its face and rostrum. The body is adorned with very fine teal lines that run horizontally across the body.
Juveniles are heavily striped, but this feature is transient and quickly disappears as the fish grows into adulthood. The adults ofZ. scopasare highly mutable, being found in a wide array of color forms and patterns. Aberrations are particularly commonplace for this species, and piebalds, xanthic and leucistic individuals have all been documented. No one is really sure why this happens, or how, but this species is very much more susceptible to variation than any other斑马瘤。Aberrations may cause confusion on the specific identity of the fish, but the presence of fine spots and striae on the body is usually diagnostic ofZ. scopas，因为这些完全不存在Z. flavescens。
The series of photos above shows a small sampling of the infinite variability of this species.Z. scopasis common and relatively cheap in the aquarium trade, but all of its variations and aberrations are expensive. This species probably hybridizes with the very closely related, and sister,斑马瘤flavescens。这两个物种在密克罗尼西亚和马歇尔群岛上显着重叠，但在日本和菲律宾的某些地区非常狭窄，而后者的这种重叠不能被认为是同伴的真实代表。存在Z. flavescensthroughout this distribution is made possible only by exceedingly rare strays and waifs, which by no means indicate a strong resident population of the species. Hybrids with the promiscuousZ. scopasare therefore not unlikely, and are most often seen in the northern regions of the Philippines and Japan. However, the existence of a xanthicZ. scopas形式使这些杂种几乎无法诊断。遗传分析也很可能也证明是徒劳的，因为这两种物种在遗传构成中都非常相似。在分析细胞色素coxidase subunit I (COI) gene, it was found that the two species differed by only less than 0.3%. This result will likely differ in a multi-locus study, but the relationships and likewise cladistic pairing ofZ. scopasandZ. flavescensin the phylogenetic tree is highly irrefutable.
斑马瘤flavescens，或者肯定地，黄色的唐是最受欢迎的斑马瘤of all time. This evergreen staple is uniformly bright yellow overall, with chartreuse accents on the edges of the fins where it is more translucent. A single glaucous stripe runs laterally across the body, and the fin membranes may be ever so slightly tinted in orange. Juveniles are similarly coloured, but as withZ. scopas，看到一系列非常细的条纹，随着鱼的生长，它们很快就消失了。Z. flavescens分布在中西部和西太平洋，从夏威夷群岛和约翰斯顿岛到马歇尔群岛，苏克，玛丽安娜群岛，菲律宾，奥加萨瓦拉和日本鲁伊基群岛。它也从台湾南部记录下来。除夏威夷以外的地方，在日本，台湾和菲律宾等地区都有罕见的地方，这种物种通常被视为流浪者，很少表明人口强劲。
Z. flavescens，就像Z. scopas, is afflicted by the exact same aberrations. These are mainly piebald and leucistic abnormalities that are less uncommon than you think. As usual, these aberrations are highly variable and below is just a small sampling of the numerous forms present. As mentioned above, this species probably hybridizes withZ. scopaswherever the two overlap, but hybrids are impossible to discern both phenotypically and genetically due to their extreme variations and similarities in genetic make up.
In conclusion, the members of斑马瘤童话般直接在表型上区分。在密切相关的紧密相关的情况下，事情变得令人困惑Z. scopasandZ. flavescens, where the two species blur the lines on their taxonomic distinctions.Z. veliferumandZ. desjardinii是独特的，完全指定的条纹进化枝成员，不能与任何其他物种混淆。Z. GemmatumandZ. Xanthurumstill remains unclear on their cladistic placement in the phylogenetic tree, but otherwise are easy enough to tell apart based on appearance.Z. rostratumand its highly elongated rostrum is most likely apomorphic to that species, and its unlikely that it forms a sister relationship withZ. scopas就像之前提到的。感谢Joe Rowlett制作了发行地图和他对此主题的见解。
