Corydoras similis

Corydoras similis
Purple Spotted Corycat
One of the more distinctively patterned species of Corydoras and therefore a nice addition to a large community tank with other corys. The colouration and intensity can vary somewhat depending upon the fish and its environment; there is a blueish colour to the blotch at the base of the caudal fin and the anterior part of the fish has a beautiful mauve or sometimes golden sheen that can be quite reflective of light. The species name similis is the Latin for "looks like," a reference to the similar colouration and pattern in Corydoras ourastigma, shown in the third photo above; this latter species has a long snout whereas C. similis is rounded.

This species might initially be confused with Corydoras guapore, C. caudimaculatus, C. spectabilis or C. ourastigma which have similar basic patterns, and except for the latter, these all occur in the Madeira/Guapore basin. Only C. similis and C. ourastigma have a "smudged" blotch at the base of the caudal fin rather than a distinct spot as in other spotted-head species. 

The aquarium should be well-planted with pieces of bogwood, a dark substrate (small gravel or sand, provided it is smooth-edged) with some open areas, and subdued lighting which can be partly achieved by floating plants; corys do not like bright lighting. Though this species will swim mid-water to browse wood and plant leaves, it spends much of its time foraging the substrate. As with all corys, mature females are rounder when viewed from above.

The Corydoras are quite sensitive to water parameters and quality, and highly intolerant of salt, chemicals and medications. Signs of stress usually begin with rapid respiration, then lethargy (often just "sitting" on plant leaves, wood or the substrate respirating heavily, sometimes near the surface) and sometimes rolling onto one side. At such signs, a partial water change of at least 50% with a good water conditioner should immediately be made, and appropriate steps taken to remove the cause. Any sudden fluctuation in water chemistry or temperature often induces shock, causing the fish to "faint" and fall over on its side. Corydoras introduced to new aquaria will settle in better if the tank is established; Cory's do not adjust well to a new aquarium with still-unstable water conditions and fluctuations.

The dorsal, pectoral and adipose fins are each preceded by a spine which is actually a hardened and modified ray; the pectoral fin spine can be "locked" into position by the fish; care must be taken when netting Cory's not to entangle these spines, which can also give the aquarist a nasty jab. They are believed to be a defense adaptation, to lodge the fish in the throat of a predator.

可是它的英文俗名,却奇怪的叫做Smudge Spot Cory,按意思直接翻译过来,叫做“污点鼠”或“污斑鼠”。这么美丽的精灵,为什么会有这么不雅的名字呢?就是因为她最显著的特征——尾柄部位的由深渐浅的蓝紫色斑点。与之类似的还有国王豹、红鳞鼠、瓜波鼠等等几种。美丽的紫罗兰原产自巴西Madeira河(流经隆多尼亚洲的马德拉水系)支流,适应ph值7.0左右的中性水,最大体长在4.5-5厘米。现在人工繁殖已经很成熟,市场也比较常见。有兴趣的朋友可以尝试下。饲养的状态好的时候身体蓝紫色的斑点伴随着金属光泽。梦幻+高雅的感觉