SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4b264fb70ca496e08a4a3bd450a929a7ab369bea9ad869b29c7559f4c74d853' 
  AND token = 'JfBSGuU9gTvLEAg4B4NkuSJ6zrtE3NyV04ZXyUGXIPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}