Tropheus sp. Limespot

Hola a todos,


En el Facebook de Africa Diving Ltd., han publicado la siguiente foto, de una supuesta nueva especie, Tropheus sp. Limespot:





Tropheus Week – Day 1

Tropheus sp. “Limespot”:
Poll’s and Brichard’s observations on Moore’s Tropheus

PART 1 of 2

Tropheus moorii is one of the most popular species of Lake Tanganyika cichlids among hobbyists and scientists alike. It was described by Boulenger in 1898 based on specimens collected by Moore in the southernmost part of the lake. Subsequent discoveries of additional Tropheus populations were usually referred to as geographical colour variants of T. moorii. This was also applied by Poll (1956: 100f) when describing the live colouration of several Tropheus populations from the Congo, referring to them as T. moorii. Some of Poll’s material originated from around Tembwe Bay and Mwerazi. Specimens from these localities, however, had a meristic anomaly. Instead of possessing six anal-fin spines, as in Boulenger’s specimens of T. moorii, Poll’s specimens from Tembwe Bay and Mwerazi had only five spines. They were, nevertheless, referred to as T. moorii. Poll (1956: 100; Pl. IV, fig. 3) described the live colouration of the Mwerazi variant as being “olive green with a yellowish belly”, and having “spots and irregular stripes of a beautiful lemon yellow colour, on the flanks of the body”, and in addition, “the dorsal and the caudal fins are adorned with lemon-yellow spots”. Following Poll in referring the Mwerazi variant to T. moorii, Scheuermann (1976) and Staeck (1985) also described it as being olive green with lemon-yellow spots and stripes, as well as having a yellowish belly.

In June 1984 Pierre Brichard discovered several new Tropheus moorii-like populations between Moba and Kapampa in the Congo, including the already known variant from Mwerazi. The latter was described as being “emerald-green, with a large lemon-coloured patch” behind the pectoral fins (Brichard 1989: 177). Other variants from neighbouring localities were also described as exhibiting such “a lemon patch on the side” or as having a “conspicuous broad circular patch 3 to 4 cm across just behind the pectoral fin. This patch is a pale yellow, pale green, or nearly white” (1989: 177). Brichard’s impression of this group of populations was that it “appears to be basically different from any we have seen in the lake so far”, alluding to the contrasting colouration. The most specific difference from similar Tropheus species in this part of the lake is the number of anal-fin spines: having five spines instead of six. Partially based on this character, Brichard classified this group of populations as a distinct lineage (here interpreted as a distinct species). This meristic character (the number of anal-fin spines) has always been important in Tropheus classification, and was initially the primary diagnostic character when separating the southernmost Tropheus (T. moorii Boulenger) from the northernmost (T. sp. “Black” Konings) (Nelissen 1979) {see a discussion on the anal-fin spines in the blog article about ‘Brichard’s Tropheus’ here: http://goo.gl/1tBK2M}.

All Tropheus variants from the Moba – Kapampa vicinity are commonly identified as T. moorii. However, following Brichard’s discoveries and observations, this is not a correct identification, and they are here referred to as T. sp. “Limespot”. Brichard’s documentation of this species (T. sp. “Limespot”) only concerned the geographical variants he found along the Congolese coast, but the similar variants of this species present along the Tanzanian coast (Lyamembe – Kalya) diagonally opposite to the northernmost part of the mentioned Congolese coast (Moba – Kapampa) are near identical, with no obvious specific differences, and therefore likely conspecific.

Part 2 follows tomorrow.

Reference;

For references, see the literature list in the blog article about Brichard’s Tropheus: http://blog.africandivingltd.com/2015/03/kushangaza-at-halembe-in-lake.html

Caption: Tropheus sp. "Limespot" at Lyamembe, depth 5 metres.



Saludos cordiales

Segunda parte:


Link:


https://www.facebook.com/africandivingltd/photos/a.1463609957203366.1073741830.1434335736797455/1610299142534446/?type=1&fref=nf


Tropheus Week – Day 2

Tropheus sp. “Limespot”:
Conspecific populations in the Congo and Tanzania

PART 2 of 2

The name Tropheus sp. “Limespot”, as this species is referred to here, dates back to both Poll’s description of the Mwerazi variant as having “spots and irregular stripes of a beautiful lemon yellow colour” and “lemon-yellow spots” (1956: 100), and to Brichard’s description of the species, to which the name is perhaps more significant: “Behind the pectoral fin extends a very large circular patch in strong contrast with the surrounding area. This patch is either lemon yellow or a ghostly white and is the only contrasting feature of the colour pattern” (1989: 176).

The specific character of Tropheus sp. “Limespot” distinguishing it from T. moorii is the number of anal-fin spines: five in T. sp. “Limespot” and six in T. moorii. The “striking colour pattern” as mentioned by Brichard is only vaguely, if at all, separable from T. moorii, which also goes for the tail fin, which is said to be larger. However, it is now possible with more advanced technology to detect even minor colourational and shape-wise differences among Tropheus populations (Herler et al. 2010). Further dissimilarities may be exposed, pending a thorough analysis.

The geographical distribution of T. sp. “Limespot” in Tanzania (Lyamembe – Kalya), which is patchy due to the sub-optimal habitat, covers about 20 km. The variant of T. sp. “Limespot” found along the rocky shore just north of Sibwesa was occasionally collected and exported by us in the nineties, by the name of T. moorii “Kibwesa” (Zadenius 1995: 43). The variant of T. sp. “Limespot” found at Nanga (in between Lyamembe and Sibwesa) was sampled by us for scientific studies in 2007 and deposited at the Swedish Museum of Natural History as Tropheus sp. “Limespot – Nanga”.

The Congolese variants of Tropheus sp. “Limespot” were collected and exported by African Diving for the first time in 1996 and concerned primarily the following four variants:

Tropheus moorii “White limespot – Mwerazi”
Tropheus moorii “Limespot yellow – Kapampa”
Tropheus moorii “True limespot – Masanza”
Tropheus moorii “Sunspot – Longola”

At the end of 2006 we collected Tropheus sp. “Limespot” at Kalya; totally 40 males and 84 females. Among the males were 2 individuals with 4 anal-fin spines, 24 individuals with 5 spines, and 14 individuals with 6 spines. Among the females were 8 individuals with 4 anal-fin spines, 52 individuals with 5 spines, and 24 individuals with 6 spines. The four spines may suggest some kind of hybridisation with T. polli, which has four anal-fin spines in this area. However, the presence of six anal-fin spines is something of a mystery, if this too is to be considered as a result of hybridisation. There are no Tropheus species in the vicinity of Kalya with exclusively six anal-fin spines. The closest northwards is T. sp. “Lukuga” at Lufungu Bay, 40 kilometres away {see blog article on ‘Brichard’s Tropheus’ here http://goo.gl/1tBK2M}, and southwards is T. sp. “Mpimbwe” {see the variant “Yellow cheek” here http://goo.gl/aHgzo7 and a map of Cape Mpimbwe here http://goo.gl/bNZj0c}. In summary, roughly two thirds of the individuals of T. sp. “Limespot” at Kalya correspond to the species characteristic of having five anal-fin spines, while one third does not. However, the latter is for the time being not interpreted as being non-conspecific, but rather as a possible result of hybridisation. (N.B. The fishes were later on, during 2007, exported to Åleds Akvarium in Sweden {link here http://goo.gl/nvCVWs}.)

Tropheus sp. “Limespot” largely corresponds to ‘Tropheus of lineage 6’ in Schupke (2003). The latter is a lineage, or species, which is stated to comprise a peculiar colouration and “a striking stripe pattern on the forehead” (2003: 69). T. sp. “Limespot” is primarily characterised on the number of anal-fin spines, which is an important diagnostic character in Tropheus, besides colouration. In contrast to ‘Lineage 6’ (Schupke 2003), T. sp. “Limespot” includes all Congolese Tropheus populations between Moba – Kapampa, because they all seem to possess an anal fin of five spines (Brichard 1989: 152, table; 176), as opposed to six spines in T. moorii (Boulenger 1898).

The molecular analysis and the phylogenetic inference of Baric et al. (2003) identified groupings of Tropheus. One of the DNA-based lineages was the so-called ‘Lineage D’, which was seemingly conforming to the morphology-based identification of T. sp. “Limespot”. The analysis also confirmed the presence of T. sp. “Limespot” populations on opposite shores — in both the Congo and in Tanzania. Evidently, the molecular analysis reflects the existence of T. sp. “Limespot” as it is presented here.

Reference;

Zadenius, M. (1995) Importnytt från Åleds Akvarium AB. Ciklidbladet, 28 (1): 42-43. Nordiska Ciklidsällskapet.

For additional references, see the literature list in the blog article about Brichard’s Tropheus: http://blog.africandivingltd.com/2015/03/kushangaza-at-halembe-in-lake.html

Caption: Tropheus sp. "Limepsot", brooding female at Kalya, depth 4 metres.

No esta nada mal, aunque me gustan con mas colorido!
un saludo

Que Tropheus mas guapo, tiene que costar una pasta...