2009年4月30日 星期四

那些印度的食神是什麼碗糕?

Schismatorhynchos nukta (="Garra" nukta) 裂吻魚 (=牛角食神)
Garra gotyla 戈泰墨頭魚 (=紅翅食神)
Garra bicornuta 雙角墨頭魚 (=紅粉食神)

這是四月份引入台灣的三種印度產墨頭魚. 其實墨頭魚屬長得都差不多, 不是受過魚類形態學與分類學的專家根本難以正確地鑑定. 這次引入台灣比較好玩的是那條"牛角食神", 牠的屬名是Schismatorhynchos, 但是我很懷疑這個屬除了頭部腫四個包, 真的和Garra有什麼不一樣嗎? 墨頭魚屬的種類通常在水族箱中被當成食藻魚, 不過這三隻印度魚的食藻能力如何, 還是只會搶飼料. 就有待飼養經驗告訴我們 (不過誰規定Garra只能吃藻類呢?)

魚隻來源: 石頭水族 & APT
圖片連結: slipperylittlesuckers.com, aqua-globe.de

2009-04-30新進魚隻

Corydoras cervinus (?) 白狐狸鼠 x 7 (人工魚)
Moenkhausia pittieri 鑽石燈 x 5

長得像cervinus的鼠魚在台灣市面上流通的有所謂的白狐狸鼠cervinus, 長吻海盜鼠sychri (longnose), 新白狐狸鼠areio, 細點白狐狸鼠, 然而我們對於這些鑑定一直有很大的疑義. 姑且不論那條魚才是真正的cervinus, 根據我們目前所初步得到的根據mtDNA序列的分析結果, 這些鼠魚的鑑定顯然有很大的問題. 所謂的長吻海盜與細點白狐狸分不開, 也與帕茲塔斯混在一起, 然後所謂的新白狐狸鼠(不同批進來的樣本)也沒有被cluster在一起. 這次由印尼繁殖的人工白狐狸鼠的種源倒底是那裏呢? 等我們把分析做一做就知道了.

魚隻來源: 台族水族
圖片連結: www.aquariogest.com, ostuka-nettaigyo (credit: 大塚 慎太郎)

2009年4月29日 星期三

Melanotaenia synergos - 產自新幾內亞西部Batana島的新種彩虹魚

文獻來源: Allen, G.R. & Unmack, P.J. 2008. A new species of rainbowfish (Melanotaeniidae: Melanotaenia), from Batanta Island, western New Guinea. aqua International Journal of Ichthyology, 13 (3-4): 109-120. [摘要下載]

Abstract A new species of rainbowfish, Melanotaenia synergos, is described on the basis of 45 specimens, 24.1-63.3 mm SL, collected in 1998 at Batanta Island, western New Guinea (Papua Barat Province, Indonesia). It is closely allied to M. catherinae from the nearby island of Waigeo in the Raja Ampat Group. The two species share similar meristic and morphological features as well as general colour pattern similarities. However, they differ in modal counts for pectoral-fin rays and lateral scales. They also exhibit slight colour pattern differences related to the width of the dark midlateral stripe, which is generally narrower in M. synergos, covering one and a half scale rows for most of its length versus 2 to 3 scale rows for M. catherinae. Analysis of genetic relationships based on cytochrome b sequences indicates a close relationship between the two species. Of four species that were analysed (M. synergos, M. catherinae, M. batanta, and M. affinis) the mean Kimura 2-parameter genetic divergences between species varied from 1.3 to 17.1%. The new species differed from M. catherinae by between 2.4 and 2.7%.

圖片連結: Rainbowfish (credit: Adrian R. Tappin)

Glyptothorax ketambe - 蘇門答臘北部紋胸鮡之一新種

文獻來源: Ng, H.H. & Hadiaty, R.K. (2009): Glyptothorax ketambe, a new catfish (Teleostei: Sisoridae) from northern Sumatra. Zootaxa, 2085: 61-68. [摘要下載]

Abstract

Glyptothorax ketambe, a new species of sisorid catfish is described from the Alas River drainage in Nangroe Aceh Darussalam Province, northern Sumatra. Glyptothorax ketambe can be distinguished from all other Sundaic congeners except G. schmidti and G. siamensis in having a color pattern consisting of a dark brown body with yellowish midlateral and mid-dorsal stripes. It differs from G. schmidti and G. siamensis in having a combination of: caudal-peduncle depth 7.6–8.9% SL, head width 16.1–17.9% SL, thoracic adhesive apparatus not reaching to the level of the base of the last pectoral-fin ray, and thoracic adhesive apparatus with an almost straight lateral margin. The identity of G. schmidti is also clarified in this study.

Garra arupi - 印度阿魯納恰爾邦布拉馬普特拉河上游產之墨頭魚新種

文獻來源: Nebeshwar, K., Vishwanath, W. & Das, D.N. (2009): Garra arupi, a new cyprinid fish species (Cypriniformes: Cyprinidae) from upper Brahmaputra basin in Arunachal Pradesh, India. Journal of Threatened Taxa, 1 (4): 197-202. [全文下載]

Abstract
Garra arupi, a new cyprinid fish species is differentiated from its congeners along the base of the Himalaya in Brahmaputra basin by a combination of characters: two pairs of barbels, anterior position of vent (vent to anal distance 52.6-60.0% pelvic to anal distance), a band of 6-9 prominent horny tubercles on the tip of the snout, a submarginal black band on the dorsal fin, and 16 circumpeduncular scales. It is similar to G. kempi in having an anterior position of the vent, and similar to G. lissorynchus in having a distinct submarginal band on the dorsal fin. Garra arupi differs from G. kempi in having 35-36 (vs. 40-42) lateral line scales, 11-12 (vs. 13-14) predorsal scales, 16 (vs. 12) circumpeduncular scales, the presence of a distinct submarginal band on the dorsal fin (vs. absence), the presence of a transverse band of tubercles on the snout tip (vs. absence), and the presence of 7-8 thin stripes on the caudal peduncle (vs. absence). Garra arupi differs from G. lissorynchus in having 11-12 (vs. 14-15) predorsal scales, 7 (vs. 6) branched dorsal fin rays, 5 (vs. 4) branched anal fin rays, the absence of a W-shaped color band on the caudal fin (vs. presence), the absence of a rostral lobe on the snout (vs. presence), the presence of a transverse band of tubercles on the snout tip (vs. absence), and a vent to anal distance 52.6-60.0 (vs. 37.3-40.2 %) pelvic to anal distance.

安曼王國墨頭魚屬之一新種 - Garra smarti

文獻來源: Krupp, F. & Budd, K. 2009. A new species of the genus Garra (Teleostei: Cyprinidae) from Oman. aqua, International Journal of Ichthyology, 15 (2): 117-120. [摘要下載]

Abstract
Garra smarti n. sp. a new species of the cyprinid fish genus Garra Hamilton, 1822 is described from Wadi Hasik, Dhofar Province, Oman, based on 11 specimens of 24.8 to 49.5 mm standard length. It differs from all other Arabian Garra by the following combination of characters: acutely pointed snout tip; anus immediately in front of anal-fin origin; 3 unbranched and 7 branched dorsal-fin rays; 34 or 35 pored scales in the lateral line, 14-16 circumpedunclar scale rows; 13-15 gill rakers on lower limb of first gill arch; mental disc small, usually longer than wide.

南美洲北部無齒刀魚科之一新種 - Brachyhypopomus bullocki

文獻來源: Sullivan, J.P. & Hopkins, C.D. (2009): Brachyhypopomus bullocki, a new species of electric knifefish (Gymnotiformes: Hypopomidae) from northern South America. Proceedings of the Academy of Natural Sciences of Philadelphia 158: 183-192. [全文下載]

Abstract
We describe the new species Brachyhypopomus bullocki (Gymnotiformes: Hypopomidae) from the río Orinoco basin of Colombia and Venezuela as well as the Takutu River/rio Branco-rio Negro basin of Guyana and Brazil. Among its congeners, B. bullocki most closely resembles Brachyhypopomus brevirostris (Steindachner, 1868) in possessing an elongated caudal filament which may reach up to 45% TL in reproductive males, in having wide, evenly spaced saddles of pigment over the dorsum connecting to lateral bands of pigment along the abdominal flanks, and in having a mesocoracoid bone. This new species is distinguished from B. brevirostris and other members of the genus by a large eye (15.5–19.2% of head length), a short abdomen usually with 12 pre-caudal vertebrae, and poorly ossified third and fourth branchiostegal rays that are enlarged distally, producing a bulbous appearance of the opercular region. The electric organ discharge waveform of B. bullocki is biphasic, 0.9–1.6 milliseconds in duration, and the pulse rate varies from 20–80 Hz.

2009年4月27日 星期一

亞達伯拉象龜的有效學名是Aldabrachelys gigantea而非Dipsochelys dussumieri

文獻來源: Frazier J. 2009. Case 3463 Testudo gigantea Schweigger, 1812 (currently Geochelone (Aldabrachelys) gigantea; Reptilia, Testudines): proposed conservation of usage of the specific name by maintenance of a designated neotype, and suppression of Testudo dussumieri Gray, 1831 (currently Dipsochelys dussumieri). Bulletin of Zoological Nomenclature [詳全文以及其它動物學者對此提議的支持]

Abstract
The purpose of this application, under Article 75.8 of the Code, is to conserve the specific name Testudo gigantea Schweigger, 1812 in its customary usage for the giant land tortoise (family TESTUDINIDAE) found on Aldabra Atoll in the western Indian Ocean. Taxonomic and nomenclatural confusion in the 19th and early 20th centuries led to competing and contradictory proposals between 1982 and 2006 to supplant T. gigantea Schweigger, 1812, first with T. elephantina Duméril & Bibron, 1835 and then with T. dussumieri Gray, 1831. As a corollary, Aldabrachelys Loveridge & Williams, 1957, the genus-group name erected for the Aldabra tortoise, was supposedly reduced to a junior synonym of either the extinct Mascarene genus/subgenus Cylindraspis Fitzinger, 1835, or the South American genus/subgenus Chelonoidis Fitzinger, 1835, and replaced as the name of the Aldabra tortoise by the generic name Dipsochelys Bour, 1982. To stabilise the accustomed name of this species as Geochelone (Aldabrachelys) gigantea, a neotype of T. gigantea Schweigger, 1812 was designated in 2006. A subsequent claim of the rediscovery of the long-lost holotype now again threatens this usage and stable nomenclature by (1) rendering T. gigantea a junior subjective synonym of T. denticulata Linnaeus, 1766, (2) resurrecting the former nomen oblitum Testudo dussumieri Gray, 1831 for the Aldabra tortoise, and (3) setting aside the neotype of T. gigantea; this action also again threatens the established use of Aldabrachelys. The supposed holotype rediscovery is not unequivocally proven, and for the sake of nomenclatural universality and stability, it is proposed that the neotype designation of 2006 be affirmed and that T. dussumieri Gray, 1831 be suppressed.

圖片連結: www.fsd2010.org (credit:Dennis Hansen)

蘇利南Corantijn河產河魟新種 - 波斯曼珍珠魟

文獻來源: Rosa, RS, MR de Carvalho and C de Almeida Wanderley (2008) Potamotrygon boesemani (Chondrichthyes: Myliobatiformes: Potamotrygonidae), a new species of Neotropical freshwater stingray from Surinam. Neotropical Ichthyology 6: 1–8. [全文下載]

Abstract
Potamotrygon boesemani, new species, is described from the Corantijn river drainage in Surinam. The species has a diagnostic dorsal color pattern formed by deep orange to red ocellated spots of irregular form, encircled by relatively broad black rings. Potamotrygon boesemani is distinguished from other ocellated congeners (P. motoro, P. henlei and P. leopoldi) by the more intensely colored ocelli, which are usually yellow in the latter species. From P. motoro it is also distinguished by the darker dorsal background coloration, by the broader black contour of the dorsal ocelli, and by the irregular form of the ocelli as compared to the more rounded shape in the latter species. From P. henlei and P. leopoldi, it is distinguished by the lack of ocelli on tail. From the tentatively identified specimen of P. ocellata, which also has dark orange ocelli, the irregular contour of the ocelli in the new species is also distinctive. The teeth are relatively smaller and in greater number than in P. motoro and P. ocellata, with up to 45 rows in the upper jaw.

2009年4月26日 星期日

那條幽靈鱷魚火箭倒底有多大隻啊?

聯合新聞網顯示的照片看起來比影音新聞顯示的那隻被斷頭的大很多耶, 而且這些影音新聞也加油添醋得太厲害了 (中天的新聞稿尤其誇張, NOWnews的敘述也不差), 一條幽靈火箭在一個社區的人工小池塘中破壞了什麼生態呢? 不過的確有些養大型魚的人太天真了, 總以為那些魚養不大, 或根本不知道自己沒有能力飼養大型魚, 隨便拿出去亂丟是真的很欠揍的行為.

讀者謝建治向本報投訴指出,他日前在高雄市三民區本和里濕地公園釣到罕見魚種「幽靈鱷魚火箭」,懷疑可能是民眾棄養後拿去濕地放生,該魚種源自北美洲,他憂心外來種生物會影響溼地生態。

謝建治指出,三月份就接獲友人通知,本和溼地裡有鱷魚,他前往察看,才發現朋友所說的是一種源自北美洲的古代魚種「幽靈鱷魚火箭」,凶猛具掠食性,該魚身長可達3公尺,鱗片為菱形,帶有金屬光澤。

謝建治使用擬餌引魚上鉤,人魚搏鬥十多分鐘才捕獲,測量結果長達110公分,他懷疑可能是民眾從水族館買回家當寵物,後來發現水族箱養不下,乾脆拿到濕地放生。

水族館業者指出,「幽靈鱷魚火箭」因長相特殊曾流行一時,牠的頭部嘴長、尖齒酷似鱷魚,看起來確實搶眼,幼魚僅十多公分,但養久了就會發現牠是龐然大物,不少飼主受限空間,常會將牠拿到池塘放養。

業者表示,幽靈鱷魚火箭屬肉食性魚類,食量不小,每天得餵上百元的活魚,而且大型熱帶魚活動力很強,不好抓住,「丟進一般池塘內,存活機率低。」因為牠適合水溫約在25度至30度之間,一般魚池空間雖足夠,但到了冬天,水溫無法維持,大型熱帶魚很容易凍死。

2009年4月25日 星期六

高雄柴山會有人棄養寵物果然名不虛傳

之前在高雄柴山都會有早起晨跑的民眾撿到很大隻又沒有隆背的蘇卡達, 這是怎麼一回事呢? 寵物跑掉或棄養真的很嚴重嗎? 喔, 終於被我們遇到了, 今天只不過去郵局領個錢, 就發現旁邊水溝裏有很大隻的斑龜, 然後助理小朋友就撿回來了. 中山大學的郵局人來人往怎麼會沒事有大斑龜在爬? 這真是太神奇了. 不過這告訴我們一件事, 很多人只因為小烏龜可愛就買來養, 完全沒有想到往後會長多大隻, 養一養不養就隨處亂放, 這才是很多外來種問題的根源. 雖說斑龜是台灣原生的龜, 不過養一養就隨便丟實在是非常糟糕又不可取的行為.

圖片連結: Malacochersus之flickr相簿

2009年4月24日 星期五

倒游鯰科的親緣關係顯示盤唇鱨亞科並非單系群

文獻來源: Vigliotta, T.R. 2008. A phylogenetic study of the African catfish family Mochokidae (Osteichthyes, Ostariophysi, Siluriformes), with a key to genera. Proceedings of the Academy of Natural Sciences of Philadelphia 157: 73–136.

ABSTRACT
A hypothesis of phylogenetic relationships is presented for the African catfish family Mochokidae based on a maximum parsimony analysis of 93 morphological characters in 41 ingroup and 19 outgroup taxa. The analysis reveals that the Mochokidae are a monophyletic group and that Mochokus Joannis (1835), Mochokiella Howes (1980), Acanthocleithron Nichols and Griscom (1917) and Microsynodontis Boulenger (1903) are monophyletic and valid as distinct genera within the family. Synodontis Cuvier (1816) must include Hemisynodontis membranacea and Brachysynodontis batensoda to be monophyletic, which are reassigned to Synodontis herein. Chiloglanis Peters (1868) is rendered paraphyletic by nested placement of Atopochilus Sauvage (1879), Euchilichthys Boulenger (1900) and Atopodontus Friel and Vigliotta (2008), a new genus described separately in this volume. Euchilichthys is rendered paraphyletic by nested placement of Atopochilus savorgnani. The monophyly of Atopochilus could not be tested because only one species was available for study. Atopodontus is monophyletic and valid as a distinct genus. Well-supported suprageneric clades within the family include a new tribe, the Atopochilini, with Atopodontus as the sister group to a clade composed of Atopochilus and Euchilichthys. A clade composed of all suckermouthed species, the redefined subfamily Chiloglanidinae, includes tribe Atopochilini nested within Chiloglanis. Taxonomic issues related to paraphyly of Chiloglanis and Euchilichthys require further research on a greater number of taxa before being addressed. Subfamily Chiloglanidinae forms a polytomy with Synodontis and Microsynodontis. Acanthocleithron, followed by Mochokiella and then Mochokus are recovered as consecutive sister groups to that polytomy. A list of synapomorphies is provided for each major clade recovered, but most clades are left unnamed at this point. A number of the well-supported clades are characterized by changes in the oral jaws and mouth, apparently a key theme in mochokid evolution. Finally, the analysis suggests that the sister group of the Mochokidae is a clade composed of the South American Doradidae plus Auchenipteridae, though support for the relationship is low. Synapomorphies supporting the recovered sister group relationship and possible synapomorphies supporting alternative sister group relationships to the Malapteruridae and Amphiliidae are provided.

圖片連結: Tree of Life (Mochokidae) (credit: John P. Friel and Thomas R. Vigliotta)

秘魯東北部Marañon河流域頸鰭鯰科之新種

文獻來源: Rengifo, B., Lujan, N.K., Taphorn, D. & Petry, P. 2008. A new species of Gelanoglanis (Siluriformes: Auchenipteridae) from the Marañon River (Amazon Basin), northeastern Perú. Proceedings of the Academy of Natural Sciences of Philadelphia 157: 181-188. [摘要連結]

Abstract
We describe a new species of driftwood catfish, Gelanoglanis travieso, (Siluriformes: Auchenipteridae) from the Marañon River, a whitewater tributary of the Amazon River in northeastern Perú. It shares with the two described species in this genus, G. stroudi, from left bank whitewater tributaries of the Orinoco River in Colombia and Venezuela, and G. nanonocticolus from blackwater tributaries of the upper Orinoco and Negro Rivers in Amazonas, Venezuela and northern Brazil, the following synapomorphies: reduced size, compressed body, conical snout, a single pair of mental barbels, premaxillae widely separated at rostral border of upper jaw, premaxillary and dentary tooth patches narrow, posterior naris long and narrow and positioned immediately anterior to orbit, and small eyes. Gelanoglanis travieso differs from all congeners in having second dorsal-fin lepidotrichium filamentous, simple, not a spine, and not serrate (shared with G. nanonocticolus); pectoral-fin spine stout, serrate along posterior margin (shared with G. stroudi); and a terminal mouth (vs. subterminal in G. nanonocticolus and G. stroudi).

雌性豬鼻飛刀沒有豬嘴

文獻來源: Cox Fernandes, C., Lundberg, J.G. and Sullivan, J. P. 2009. Oedemognathus exodon and Sternarchogiton nattereri (Apteronotidae, Gymnotiformes): the case for sexual dimorphism and conspecificity. Proceedings of the Academy of Natural Sciences of Philadelphia, 158: 193-207.

裸背電鰻科(=光背電鰻科)的頭型與吻部的極端雌雄二型性, 以及不同雄性個體間極大的多態型在1990年代之後開始被發掘並正視其對分類系統的影響, Cristina Cox Fernandes則是近年對於這個議題研究最力的學者, 無論是黑傑克飛刀, 火鶴飛刀或是恐龍飛刀都是她近年的重要研究成果. 在這篇文章中她與她的同事闡明了豬鼻飛刀(Oedemognathus exodon)(亦稱腫齒裸背電鰻)與納氏寬兇裸背電鰻(Sternarchogiton nattereri)其實是同一個物種, 而雄性齒列的誇張外翻則可能與種內競爭有關. Sazima雖然在1983年對於食鱗性魚類的整理中列舉了豬鼻飛刀, 但是這項推測目前並沒有被任何的(包括我們的)飼養經驗所證實. 台灣在近幾年所進口的"龍鱗飛刀"(如下圖)是否為Sternarchogiton nattereri則還需要進一步的鑑定.

Abstract
Oedemognathus exodon, a monotypic genus and species of Amazonian apteronotid electric fishes, is based on a single specimen with uniquely externalized jaw teeth projecting from a bulbous snout. Recently, many additional specimens of Oedemognathus, all mature males, have been collected in the Amazon by trawling in channels and seining in floating vegetation mats. These new specimens were collected with many monomorphic female, male and immature specimens of Sternarchogiton nattereri, a related and similar species. On this basis we suggested a hypothesis of sexual dimorphism and conspecificity for O. exodon and S. nattereri. Although this idea has been taxonomically accepted by recent authors with treatment of O. exodon as a junior synonym of S. nattereri, the evidenciary basis for this remains unpublished. Herein we present that evidence. In addition to being associated at sexual maturity during breeding season, S. nattereri and O. exodon are closely similar in external and internal morphology, pigmentation, and mitochondrial cytochrome b sequences. Furthermore, we observe that the striking dentition, jaw and snout morphology of Oedemognathus has its developmental origin in mature males that are equal, or nearly so, in size to non-dimorphic S. nattereri.

紅蓮燈的緊迫程度可藉偵測其螢光光譜變化而得知

文獻來源: Brinn RP, Marcon J, Tavares-Dias M, Brinn IM. 2008. Fluorescence Detection of the Ornamental Fish Cardinal Tetra (Paracheirodon axelrodi). Photochemistry and Photobiology 85(1): 358-364. [摘要連結]

延伸閱讀: 綠蓮燈體色的日夜間變化

Abstract
The fluorescence spectra of the tropical fish, Cardinal Tetra (Paracheirodon axelrodi), originating in the Amazon region of Brazil, were determined. These spectra were then treated using factor analysis, generating two contributing spectra and separating out the noise. Time-resolved fluorescence results indicated that the fluorescent system in the epidermis undergoes excited state reaction. Excited state proton transfer is suggested as being present. Both intentionally stressed and nonstressed individuals were used and some small differences were noted in the contributions of the two calculated contributing spectra to the experimental spectra, presumably as a function of stress. The results are compared with those obtained by the standard determination of cortisol level using the whole body extraction method and it is suggested that the method could be tested as an improved, nondestructive way to determine stress in this species, which is a necessary step in the development of "best management practices" of methods for storage and transport of the fish.

2009年4月23日 星期四

海南淡水龜類貿易現狀與管理建議

文獻來源: 龔世平, 符有利, 汪繼超, 史海濤, 徐汝梅. 2005. 海南淡水龜類貿易現狀與管理建議. 生物多樣性13(3): 239-247 [全文下載] (Gong SP, Fu YL, Wang JC, Shi HT, Xu RM. 2005. Freshwater Turtle Trade in Hainan and Suggestions for Effective Management. Biodiversity Research 13(3): 239-247.)

摘要
對海南野生淡水龜類貿易進行了調查。調查發現海南所有市縣都存在野生龜類貿易,有野生龜類貿易的農貿市場22個,占調查農貿市場總數的19.6%;有野生龜類貿易的鄉鎮64個,占調查鄉鎮總數的65.3%;野生龜類收購點103個,野生淡水龜共489只。野生龜貿易所涉及的淡水龜類共10種,占海南淡水龜分佈總種數的90%以上,其中3種是國家二級重點保護動物,6種是列入《瀕危野生動植物種國際貿易公約》附錄Ⅱ的物種。按照《中國瀕危動物紅皮書(兩栖類和爬行類)》,1種為極危物種,8種為瀕危物種,1種為易危物種。在個體數量方面,以鋸緣攝龜(Pyxidea mouhotii)、黃額盒龜(Cuora galbinifrons)、四眼斑水龜(Sacalia quadriocellata)和中華花龜(Ocadia sinensis)較多,平胸龜(Platysternon megacephalum)、地龜(Geoemyda spengleri)、中華鱉(Pelodiscus sinensis)較少,三線閉殼龜(Cuora trifasciata)、黃喉擬水龜(Mauremys mutica)和山瑞鱉(Palea steindachneri)極其稀少。龜類市場價格差異很大,從2002年到2004年,各種龜的價格都有不同幅度的上漲。分析表明:淡水龜類非法捕獵與貿易在海南普遍存在,過度捕獵對海南淡水龜類構成了嚴重威脅,而野生龜貿易則是導致過度捕獵的主要原因。本文在分析和探討海南野生淡水龜類貿易的現狀、原因及危害的基礎上,針對當前保護管理中存在的問題,提出了相應的保護管理建議。

Abstract
A survey of the freshwater turtle trade in Hainan was conducted during 2002-2004. The results show that trade in wild turtles occurs in all cities and counties of Hainan. A total of 22 markets selling turtles were found, accounting for 19.6% of the total markets investigated and trade in wild turtles was found to exist in 64 towns, accounting for 65.3% of the total towns investigated. A total of 103 wild turtle purchasing stations were discovered, comprising 489 wild individuals and 10 local species (more than 90% of Hainan's freshwater turtle species). Of the 10 turtle species, 3 are designated as grade II key state-protected species and 6 listed on Appendix II of the Convention on International Trade in Endangered Species (CITES). According to the China Red Data Book of Endangered Animals: Amphibia and Reptilia, 1 is critically endangered, 8 endangered and I vulnerable in China. According to the number of individuals found in this survey, Pyxidea mouhotii, Cuora galbinifrons, Sacalia quadriocellata, Ocadia sinensis are relatively abundant; Platysternon megacephalum, Geoemyda spengleri, Pelodiscus sinensis are rare; Cuora trifasciata, Mauremys mutica, and Palea steindachneri are critically rare. The market prices of these turtle species vary widely, ranging from RMB80-120 per kilogram in S. quadriocellata to RMB 18000-36000 per kilogram in C. trifasciata. From 2002 to 2004, the prices have risen to a varying degree. This study shows that the wild turtle trade is widespread in Hainan. The demand of the trade has led to over-collecting, which is the largest threat to the freshwater turtles of Hainan. Here the status, reasons, and negative impacts of wild turtle trade are discussed and possible suggestions for effective management and conservation are presented.

圖片連結: violet之相簿

2009-04-03新進魚隻

Corynopoma riisei 龍王燈 x 4 (我知道這很便宜, 可是一般盤商不進啊, 就變成夢幻逸品了)
Puntius pentazona 五間鯽 x 3

龍王燈這條魚其實非常有趣, 雖然因為東南亞大量繁殖的因素導致很多盤商認為無利可圖, 在台灣市面上的能見度極低, 不過龍王燈所屬的Glandulocaudinae亞科因其所具有的尾柄腺體(caudal gland)及鰓蓋所具有的鰓腺(gill gland)令這個類群(含金國王燈, 三色燈, 炫彩藍燈等魚)在脂鯉科的演化上深受囑目. 龍王燈雄魚鰓蓋上的長柄結構早在1960年代即由Nelson(1964)與Wickler(1958)所討論, 而其鰓蓋腺體直到Burns與Weitzman發表於1996年的文章被確認為
雄性的第二性徵. Arnqvist & Rowe(2005)以及Arnqvist(2005)對於龍王燈鰓蓋上那根長柄的用途做了推測, 他們認為那根長柄的用途是以形似食餌的形態誘騙雌魚接近, 藉以增加交配的機會 (以行為生態學裝模作樣的術語來說, 這樣叫作"以剝削雌魚的取食偏好達到雄性的目的"). 雖然這條魚已經在東南亞被大量地繁殖, 在日本也有玩家觀察到產卵行為, 不過這個鰓蓋上的長柄倒底在實際上如何用以誘引雌魚似乎還沒有較深入的研究與觀察, 如果能夠再買到更多就好了.

魚隻來源: 哲園水族(台中大里)
圖片連結:
seriouslyfish.com (credit: CK Yeo)

2009年4月22日 星期三

三角變色龍與變色龍屬應被視為獨立的兩個屬

文獻來源: Tilbury CR, Tolley KA. 2009. A re-appraisal of the systematics of the African genus Chamaeleo (Reptilia: Chamaeleonidae). Zootaxa 2079: 57–68. [摘要下載]

Abstract
The genus Chamaeleo, currently subdivided into two sub-genera, Chamaeleo (Chamaeleo) and Chamaeleo (Trioceros) (Klaver & Böhme 1986), is reviewed from both a morphological and genetic basis and it is concluded that the two subgenera are sufficiently distinct as to warrant their formal elevation to seperate and distinct genera. Evaluation of the soft anatomy and several other characters provide sufficient basis for making this distinction. The proposed change is supported by the demonstration of monophyletic groupings (based on two mitochondrial and one nuclear gene) consistent with distinct genera.

圖片連結: thegardensofeden.org

2009年4月21日 星期二

豹紋(=七彩)變色龍因食物維它命D含量調整日光浴行為

文獻來源: Karsten KB, Ferguson GW, Chen TC, Holick MF. 2009. Panther Chameleons, Furcifer pardalis, Behaviorally Regulate Optimal Exposure to UV Depending on Dietary Vitamin D3 Status. Physiological and Biochemical Zoology 82 (3): 218 DOI: 10.1086/597525

Abstract
Reptiles may bask for reasons other than thermoregulation. One alternative is to regulate homeostasis of vitamin D3, a hormone essential to the health of many reptiles. Maintenance of vitamin D3 homeostasis requires either regulation of exposure to ultraviolet radiation (UV) or ingested vitamin D3. However, the prey items of most vertebrates tend to be low in vitamin D3. Thus, basking may be the primary opportunity for vitamin D3 regulation. We tested the hypothesis that panther chameleons (Furcifer pardalis) behaviorally regulate exposure to UV in natural sunlight with high precision, accuracy, and effectiveness. Panther chameleons with low dietary vitamin D3 intake significantly increased exposure to UV in natural sunlight compared to those with high dietary vitamin D3 intake. All lizards fed low dietary vitamin D3 regulated within optimal UV levels with extreme effectiveness (ability to regulate within optimal UV levels relative to available UV). Chameleons of both dietary treatments regulated UV exposure with great precision, exhibiting little variation among individuals within treatments. Our results add to a growing body of literature that empirically demonstrates the importance of basking for nonthermoregulatory purposes and, more specifically, as an integral mechanism for the regulation of a vital hormone, vitamin D3.


另可參見Sciencedaily之科普介紹

圖片連結: Dimijianimages.com

2009年4月20日 星期一

野生動物保育彙報及通訊 2009, 13(1)

最近一期的精采內容如下, 全文請由此下載

外來入侵鳥種白腰鵲鴝( Copsychus malabaricus)對台灣生物多樣性的衝擊

林育秀、范孟雯、方偉
消逝的樂章:綠繡眼
林昱伶
兩棲類入侵與亞洲錦蛙在台灣的分布現況
陳清旗、韋昕林、侯平君
亞洲錦蛙很毒
李勝雲
台灣半水棲蛇類面臨的困境
毛俊傑
台灣東部溪流外來魚種探討
韓僑權、李展榮
台灣長鬃山羊自然族群感染疥癬之現況
陳貞志、裴家騏

青海產蟾頭蜥一新種 - 桂南蟾頭蜥

文獻來源: Xiang JI, Wang YZ, Wang Z. 2009. New species of Phrynocephalus (Squamata, Agamidae) from Qinghai, Northwest China. Zootaxa 1988: 61-68. [摘要下載]

Abstract
A new viviparous species of Phrynocephalus from Guinan, Qinghai, China, is described. Phrynocephalus guinanensis sp. nov., differs from all congeners in the following combination of characters: body large and relatively robust; dorsal ground color of head, neck, trunk, limbs and tail brown with weak light brown mottling; lateral ground color of head, neck, trunk and tail light black with weak white-gray mottling in adult males, and green with weak white-gray mottling in adult females; ventral ground color of tail white-gray to black in the distal part of the tail in adult males, and totally white-gray in adult females; ventral surfaces of hind-limbs white-gray; ventral surfaces of fore-limbs brick-red in adult males, and white-gray in adult females; ventral ground color of trunk and head black in the center but, in the periphery, brick-red in adult males and white-gray in adult females. Phrynocephalus guinanensis sp. nov. typically uses desert habitats, whereas P. vlangalii, a species closely related to the new form, uses a variety of arid and semi-arid habitats. It is the nineteenth species of Phrynocephalus recorded from China.

中國西南高黎貢山產鈍頭蛇屬一新種

文獻來源: Guo, K.; Deng, X. 2009: A new species of Pareas (Serpentes: Colubridae: Pareatinae) from the Gaoligong Mountains, southwestern China. Zootaxa, 2008: 53-60. [摘要下載]

Abstract
A new species of Pareas Wagler, 1830 (Serpentes: Colubridae: Pareatinae) is described from Gaoligong Mountains, Yunnan province, southwestern China. The new species is distinguished from congeners in the following combination of traits: preoculars 1/1; subocular and postocular fused into a single crescent-shaped scale; anterior temporals 1, posterior 2–3; 15 dorsal rows on whole body, 9 median rows feebly keeled (invisible on neck); vertebral scales slightly enlarged; ventrals 175; subcaudals 76 (excluding terminal spine), all divided; a big black oval patch on the back of head; two round black spots on each side of the face.

馬來半島產東虎屬的兩個新種

文獻來源: Grismer LL, Ahmad N, Onn CK, Belabut D, Muin MA, Wood Jr PL, Grismer JL. 2009. Two new diminutive species of Cnemaspis Strauch 1887 (Squamata: Gekkonidae) from Peninsular Malaysia. Zootaxa 2019: 40–56. [摘要下載]

Abstract
Two new diminutive species of Cnemaspis are described from Peninsular Malaysia. Cnemaspis monachorum sp. nov. is a karst-dwelling species endemic to Pulau Langkawi, Kedah and is the smallest species of Southeast Asian Cnemaspis to date. Cnemaspis pseudomcguirei sp. nov. is a montane species known only from Bukit Larut, Perak in the Bintang Mountain Range and is very similar in appearance to the considerably larger, sympatric species C. mcguirei. Evidence supporting a working hypothesis of resource partitioning between sympatric species pairs of Cnemaspis on the basis of size and microhabitat preference is presented.

非洲產火燄石龍子種群的分類檢討及氣候變遷在其種化過程所扮演的角色

文獻來源: Wagner P, Böhme W, Pauwel OSG, Schimitz GP. 2009. A review of the African red–flanked skinks of the Lygosoma fernandi (BURTON, 1836) species group (Squamata: Scincidae) and the role of climate change in their speciation. Zootaxa 2050: 1–30 (2009) [摘要下載]

火燄石龍子是台灣爬蟲寵物市場上相當常見的物種, 不過其鑑定與學名的使用卻相當混亂, 其學名通常以Lygosoma fernandi, Riopa fernandiMochlus fernandi的形式呈現. 這篇文章根據12S與16S mtDNA序列的分析認為火燄石龍子種群根本不屬於這幾個屬, 而應該重新回復至Lepidothyris屬中, 也就是說, 火燄石龍子的有效學名組合應該是Lepidothyris fernandi. 但是市售的火燄石龍子倒底是那一個分類群呢? 根據這篇文章的見解, 原名亞種L. f.f.產於喀麥隆至奈及利亞, 而L. f. harlani則分布在獅子山, 象牙海岸, 賴比瑞亞至迦納的幾內亞灣以北區域. 兩者最主要的差別除了鱗片數目等量化特徵的差異外, 主要的鑑識特徵則是前肢與後肢間黑色縱紋的數目. L.f.f.約在10條以上, 而L.f.harlani則在9-10條間. 台灣市面上流通的個體應該是那一個亞種則應該要仔細的鑑定了.

Abstract
We present an analysis of the morphometric and genetic variability of Lygosoma fernandi. Geographical variation and taxonomic consequences are discussed and Lepidothyris Cope, 1892 is resurrected as genus for the L. fernandi species group. The results show that Lepidothyris fernandi sensu lato is a species complex, which comprises an eastern and a western species. Each of them has a further subspecies of its own, and a third distinct species is present in southwestern Central Africa. The morphological and genetic differences between these taxa are analyzed resulting in the description of two new taxa, and the resurrection of two more taxa.

圖片連結:
natureswindow.dk (credit: Rune Midtgaard)

柬埔寨龍魚之採獲, 貿易與保育現況

文獻來源: Rowley JJL, Emmett DA, Voen S. 2008. Harvest, trade and conservation of the Asian arowana Scleropages formosus in Cambodia. Aquatic Conservation: Marine and Freshwater Ecosystems 18(7): 1255-1262. [摘要下載]

Abstract
  1. The worldwide trade in aquarium fish is a multi-billion dollar industry. One of the most popular and expensive species traded is the Asian arowana Scleropages formosus. As a result of over-harvesting for the aquarium fish trade, S. formosus is now endangered and commercial international trade in the species is prohibited under CITES. Despite this, very little is known about S. formosus in the wild.
  2. Interviews were conducted with 62 local villagers at four sites in Koh Kong province, south-west Cambodia, to obtain information on the reproduction, historical and current harvest and trade, and population trends of S. formosus.
  3. The spawning season of S. formosus in Cambodia begins towards the end of the dry season (March-April) and is approximately 3 months in duration. Each male mouth-broods an average of 30 juveniles. Harvesters target S. formosus fry and juveniles, and typically kill or frighten brooding males into releasing their offspring in order to harvest them.
  4. The prices obtained by harvesters for S. formosus has been increasing since collection began, and currently averages $US11-13 per juvenile. After collection, fish are transported through a series of larger towns, most ultimately bound for Thailand. The current number of S. formosus harvested from the wild in Cambodia is almost certainly highly unsustainable, with all respondents indicating that local S. formosus population abundance had declined dramatically in recent years. It is also likely that a number of populations have already become locally extinct.
  5. Strengthening legislation to protect the species within Cambodia, increasing enforcement of cross-border trade, and an investigation into alternative low-impact income generation opportunities for local communities is vital. There is also an urgent need to gather detailed information on the distribution, population abundance and threats facing S. formosus in Cambodia, and in other countries throughout its range.
圖片連結: awowana.asia

巴西Paraná上游產金十字具有兩個核型

文獻來源: Pazza R., Kavalco S. A. F., Penteado P. R., Kavalco K. F., De almeida-toledo L. F.:2008. The species complex Astyanax fasciatus Cuvier (Teleostei, Characiformes) – a multidisciplinary approach. Journal of Fish Biology 72(8): DOI: 10.1111/j.1095-8649.2008.01837.x

ABSTRACT
Cytogenetic data have provided important clues that the Astyanax fasciatus populations from the Upper Paraná River basin could be a part of a more diverse fish group, usually included on the same taxa. Samples collected in Cachoeira de Emas, SP, in Mogi-Guaçu River basin, show two major cytotypes presenting 2n = 46 and 2n = 48 chromosomes, with distinct karyotypic formula, despite the fact that the molecular data suggested some degree of gene flow between these cytotypes. Cytogenetic and morphometric analyses were performed in this species, aiming to contribute to the understanding of the natural history from such fish group. Two allopatric populations with distinct standard cytotypes were analysed, and the data obtained suggest the separation into two groups.

圖片連結: aquarium.ru

細胞學證據顯示巴西伊瓜蘇河上游的麗脂鯉可能高達11種

文獻來源: Kantek D. L. Z., Noleto R. B., Maurutto F. A. M., Bertollo L. A. C., Moreira-filho O., Cestari M. M. 2008. Cytotaxonomy of Astyanax (Characiformes, Characidae) from the Upper Iguaçu River Basin: confirmation of the occurrence of distinct evolutionary units. Journal of Fish Biology 73(8): DOI: 10.1111/j.1095-8649.2008.02030.x

ABSTRACT
Taxonomic studies of the genus Astyanax from the Iguaçu River (Brazil) indicate that they may be differentiated into 11 distinct species, some of which have not been formally described and named so for. This study focuses on three of these species, Astyanax sp. B, Astyanax sp. C and Astyanax sp. D from the Upper Iguaçu River Basin. Comparative cytogenetic analyses of C-banding, Ag-NORs (silver nitrate stained nucleolar organizer region) and 18S and 5S rDNA corroborate that they are distinct species. A diploid number of 50 chromosomes and similar karyotypic formulae were observed in the three taxa, with the exception of Astyanax sp. D that differs in the number of submetacentric and subtelocentric chromosomes. However, the NOR silver-staining pattern, the heterochromatic bands (C-bands) and the mapping of the 18S and 5S rDNA sites in the chromosomes showed divergences between all three species under study, supporting the occurrence of distinct evolutionary units.

圖片連結: The Age of Aquariums (credit Helios Medina)

大蓋巨脂鯉的微衛星體標誌

文獻來源: Santos, M. C. F.*, T. Hrbek, and I. P. Farias. 2009. Microsatellite markers for the tambaqui (Colossoma macropomum, Serrasalmidae, Characiformes), an economically important keystone species of the Amazon River floodplain. Molecular Ecology Resources [摘要下載]

ABSTRACT
Colossoma macropomum is a keystone species of the Amazon floodplain, and is an important but severely overexploited commercial species. To provide tools for addressing ecological and conservation questions, we developed 14 highly polymorphic microsatellite markers that had between four and 21 alleles per locus in the 25 tested individuals. With the exception of comparisons involving the locus Cm1F5 that also showed heterozygosity deficiency, no pairs of loci were at linkage disequilibrium. Many of the microsatellite loci were also variable in three other serrasalmid species which span the phylogenetic depth of the Serrasalmidae.

圖片連結: wikipedia

2009年4月18日 星期六

那些仿製PH的濾材

Power House的濾材就像ADA的東西一樣, 目前被明星化, 被說得一副很頂極的樣子, 而且就一整個是天價. 小小5L的幾顆東西, 最便宜也是要5000元, 據說代理PH的廠商不是水族業, 所以價錢很硬, 而且硬到也很難做什麼折扣. 嗯, 5L的陶磁環可以擺幾層上部過濾槽呢? 如果是一個4尺缸, 相信根本就擺不滿, 濾材比整缸的魚來要貴, 有沒有搞錯? 本來是很想試試PH的陶磁環是否真的有那麼神奇, 但是東想西想, 網路上的價錢也沒有比較便宜, 然後一般量販店也不太喜歡賣PH的東西, 買個兩盒5L的要價一萬元, 換算成航空聯名卡的哩程也頂多285哩, 投資報酬率極低, 因此我們就開始找PH的替代品. PH濾材在設計上最令我覺得有創意的是縮小陶磁環的尺吋, 這樣可以讓小型的圓桶, 外掛與上部過濾槽都可以置入更多的陶磁環. 而這樣的小尺寸是傳統品牌的陶磁環所沒有的. 此外, PH的陶磁環據說孔隙很多, 不像很多陶磁環根本就只是作作樣子的消波塊, 所以呢PH可培菌的面積據說較大, 但, 這是真的嗎? 有這樣神奇嗎? 以前的人養魚沒有陶磁環就有死過東西嗎? 以前不是都跟人家拿舊砂或舊綿也就養了起來嗎? 為什麼現在大家使用陶磁環和上部過濾盒都疊得比天高? 是在玩樂高嗎? 還有人把疊得很高的過濾槽拿來貼圖, 這是怎樣啊?

台灣的市面上突然出現了很多擺明就是仿冒PH商標設計與產品的濾材, 也就是把商標的兩個字母大寫, 基本上我覺得這種仿傚實在是很沒創意, 例如Power Material縮寫成PM, 然後Mr. Axxa就變成MA, 可是我們又很想試試小尺吋的陶磁環, 但又花不起錢買PH產品, 怎麼辦呢? 只好找像一點的仿製產品嗎? Mr. Axxa其實直接被我們淘汰, 因為這個牌子缺乏小一點的尺吋, 而且仔細看每一個陶磁環的內面根本就是光滑的, 完全不是產品所宣稱的多孔隙, 而且包裝袋裏的粉一大堆, 真懷疑那些粉溶進水裏變成啥? 我們勉強考慮PM產品, 是因為PM有小尺吋的陶磁環, 但是比上PH的產品, 還是大了一號, 而且那個精製度看得出來有差別, 但我們比較了PM與PH陶磁環的內面後發現, 其實肉眼可見的孔隙沒有差很多捏....(當然, 我們在店面內沒有辦法用顯微鏡看清楚那些孔隙倒底是只有表面有, 還是內部也有, 就像故宮那個象牙轉球一樣), 所以, 我們就決定先用PM試看看. 目前我們把PM濾材填充在上部過濾器內, 而且故意丟進有藍綠藻問題的象鼻魚缸中(晒得到太陽), 看看問題是否會有所改善. 當然, 水質的管理有很多層面得考量, 就算買了10萬塊的PH濾材也不表示問題就可以解決, 不過至少我們先試試看改變陶磁環大小與密度是不是會對水質的改善有一點幫助.

04/19: 藍綠藻馬上蓋住那些新的陶磁環, 這顯示大地之母對人類科技的反撲嗎? (喔 我們好會嘴砲啊~~~)
04/23: 在加入新的濾材以後, 其實缸內的藍綠藻就幾乎消失, 取而代之的是褐色的藻類(那是還好, 而且有魚會吃), 看起來PM的濾材並不差, 還算是可以使用的. 所以我們決定把陶瓷環全面換成PM的

2009年4月17日 星期五

印度東北產鱧屬魚類的鑑定與種間關係

文獻來源: Vishwanath W, Geetakumari Kh. 2009. Diagnosis and interrelationships of fishes of the genus Channa Scopoli (Teleostei: Channidae) of northeastern India. Journal of Threatened Taxa 1(2): 97-105. [全文下載]

Abstract :
Diagnostic characters of nine species of the genus Channa Scopoli of northeastern India are given. Examination of morphological and osteological characters revealed that the fish under study comprised two phylectic groups: marulius and gachua. The Marulius group is characteristic by having a very prominent V-shaped sharp isthmus, cephalic sensory pores arranged in groups, absence of scales on the lower jaw, a sharp prominent spinelike hypurapophysis, more branchial toothplates than epibranchial, and an elongated urostyle. The Gachua group is characterized by a U-shaped isthmus, cephalic sensory pores evenly arranged in a single row, the presence of one or two large cycloid scales on each side of the lower jaw, absence of a sharp prominent spine-like hypurapophysis, absence or presence of one tooth plate in the epibranchial, and absence of an elongated urostyle. An elongated bone is present in between two last hemal spines of all species examined. A key to known species of Channa of northeastern India is also given.

2009-04-17新進魚隻

Hemigrammus pulcher 貝蒂燈 x 6 (可愛又被養胖又便宜所以就買了)
Characidae sp. 雜燈一枚 x 1 (混在彩虹帝王燈中)
Garra flavata 熊貓青苔鼠 x 10

魚隻來源: 永信水族(文衡店)
圖片連結:
otsuka-nettaigyo

馬拉威湖三個非洲鳳凰的新種與M. vermivorus的重新描述

文獻來源: Konings-Dudin G, Konings AF, Stauffer Jr JT. 2009. Descriptions of three new species of Melanochromis (Teleostei: Cichlidae) and a redescription of M. vermivorus. Zootaxa 2076: 37-59. [全文下載]

Abstract
The Lake Malaŵi genus Melanochromis included five species at its inception and was originally distinguished from Pseudotropheus on the basis of morphology including the arrangement of pharyngeal teeth. The diagnosis has been extended twice, first to include all elongate mbuna that possess horizontal stripes and U-shaped tooth bands and later to exclude mbuna that do not exhibit a sex-related reversal in their color pattern. We have further refined the diagnosis of the genus on the basis of the melanin pattern, resolved a longstanding dispute regarding the validity of M. heterochromis, re-evaluated the status of M. vermivorus, synonymized M. mellitus Johnson 1976 with M. melanopterus Trewavas 1935, moved M. benetos Bowers and Stauffer 1977 to Pseudotropheus, and described M. kaskazini, M. wochepa, and M. mossambiquensis from the eastern shore of the lake. Melanochromis is still paraphyletic as two species, M. joanjohnsonae Johnson 1974 and M. labrosus Trewavas 1935, are not congruent with the rest of the group, but, currently, a better alternative for these two could not be found.

鬣蜥與蛇蜥亞目雞雞的形態用於推測演化關係上比外部形態有用

文獻來源: Böhme W, Ziegle T. 2009. A review of iguanian and anguimorph lizard genitalia (Squamata: Chamaeleonidae; Varanoidea, Shinisauridae, Xenosauridae, Anguidae) and their phylogenetic significance: comparisons with molecular data sets. Journal of Zoological Systematics and Evolutionary Research 47(2): 189-202. [連結]

ABSTRACT
We compare phylogenetic hypotheses for iguanian (chameleonids) and anguimorph lizard groups (varanoids, xenosauroids, anguids) which were generated from analyses of genital (hemipenial) morphology, with recent molecular phylogenetic approaches towards the same groups. Taxa with infraspecific communication by means of visible, sexually dimorphic epigamic characters usually have less diverse genital structures than taxa with less developed visible epigamic characters but with a more highly developed chemical intersexual communication. Generally, it turned out in the cases considered here, that phylogenetic hypotheses based on hemipenial characters coincide much better with molecular-genetic phylogenies than with earlier concepts based solely on external morphology. It seems that genital morphological characters are phylogenetically more informative – on both the species and the supraspecific level – than external morphological characters at least in these examples, because the former seem not to be affected by environmental selective pressures but seem to be only subject to sexual selection. Our data suggest that sexual selective pressure on genital structural diversity is higher the less sexually dimorphic, optical cues for infraspecific communication have evolved. They further suggest a correlation with the mating system (single versus multiple matings).

守宮愈大隻抓得愈不牢?

文獻來源: Webster, N.B., Johnson, M.K. and Russell, A. P. 2009. Ontogenetic scaling of scansorial surface area and setal dimensions of Chondrodactylus bibronii (Gekkota: Gekkonidae): testing predictions derived from cross-species comparisons of gekkotans. —Acta Zoologica (Stockholm) 90: 18–29. [連結]

ABSTRACT

Little is known of how the adhesive apparatus of gekkotans scales with growth. Cross-species comparisons of certain characteristics, using size as a comparator to investigate scaling relationships, suggest certain relationships between subdigital pad area and body size. The manner in which the adhesive apparatus grows and scales within any one species, however, remains unknown, and it is unclear whether interspecific and intraspecific patterns are similar. To address this, we examined a post-hatching ontogenetic series of the southern African gecko Chondrodactylus bibronii and demonstrate that setal density, setal basal diameter and setal spacing remain relatively constant in relation to size, indicating conserved subdigital pad assembly rules that are independent of size. Conversely, however, average and maximal setal lengths increase slightly and isometrically with size, an outcome that is probably explained by setal row recruitment, and the surface area of the subdigital pads scales close to, but below, isometry with respect to body mass and snout–vent length, it therefore does not increase sufficiently with size to compensate for the increase in mass. As a result, relative adhesive capacity decreases with growth with a regression slope of –0.45.

圖片連結:
bushsnake發表於南非SA Reptiles論壇之圖片

加入圖片

金國王燈之巴西內陸與沿岸族群具有顯著遺傳分化

Torres RA, Motta TS, Nardino D, Adam ML, Ribeiro J. 2009. Chromosomes, RAPDs and evolutionary trends of the Neotropical fish Mimagoniates microlepis (Teleostei: Characidae: Glandulocaudinae) from coastal and continental regions of the Atlantic forest, Southern Brazil. Acta Zoologica 89(3): 253-259. [連結]

ABSTRACT
Chromosome and random amplified polymorphic DNA (RAPD) markers of samples of Mimagoniates microlepis were studied to test the hypothesis that a vicariant event occurred as the result of the orogeny of the coastal mountain range (Serra do Mar; southeastern and southern Brazil). Conventional karyotypes and nucleolar organizer region (Ag-NOR) phenotypes of two samples of M. microlepis from the headwaters of the Iguaçu River (southern Brazil) were compared both with each other and with other local populations of the species in the coastal drainage of southeastern Brazil. Additional molecular data (RAPD markers and genetic diversity) were obtained from specimens from coastal and continental regions of southern Brazil. The same diploid number (52 chromosomes), karyotypic formula and Ag-NOR phenotype were found for both analysed samples from the Iguaçu River. A genetic discontinuity was discovered in the comparison of the karyotypical formula of the Iguaçu samples with those from coastal drainages of the region. Polymerase chain reaction-RAPD markers revealed strikingly different molecular profiles between coastal and continental samples and indications of a high degree of genetic variation. Based on these results, we provide some comments on the biogeographical patterns and evolutionary trends for M. microlepis from coastal and continental regions of southeastern/southern Brazil.

冰河週期與海平面升降造就奇莖鱂的高度分化

文獻來源: Jones CP, Johnson JB. 2009. Phylogeography of the livebearer Xenophallus umbratilis (Teleostei: Poeciliidae): glacial cycles and sea level change predict diversification of a freshwater tropical fish. Molecular Ecology 18 (8): 1640-1653. [連結]

ABSTRACT

The biogeography of Central America is viewed as a classic case study in understanding the impact of vicariant events on patterns of biotic dispersal. While many biogeographers have focused on community composition and geographical limits of species at broad scales across Central America, much less work has focused on post-colonization diversification patterns at finer scales. The livebearing freshwater fish Xenophallus umbratilis presents an ideal system for determining the impact of recent Earth history events on biodiversity in northern Costa Rica. Here, we test the hypotheses that marine inundation of the San Carlos and northern Limón basins during the Pliocene and Pleistocene has caused genetic fragmentation among X. umbratilis populations, despite contemporary freshwater connections. To test this idea, we collected mitochondrial (cytochrome b) sequence data in 162 individuals taken from 27 localities across northern Costa Rica. We employed a variety of analytical approaches, including: maximum parsimony and maximum likelihood, analysis of molecular variance, and demographic analysis of population size through time. We found four major clades within X. umbratilis, each geographically isolated with no shared haplotypes across drainages. Oddly, clades that occupy adjacent drainages are not always sister taxa in the phylogeny, suggesting that colonization in this species is more complex than a simple model of isolation by distance. All our results are consistent with the hypothesis that changes in sea level associated with glacial eustatic cycles have had an important effect in shaping diversification patterns in this species.

圖片連結: www.britishlivebearerassociation.co.uk (credit: Håvard Støre Andresen)