SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '656d29ebec62d8b06d7c2c30d3d3eed8937f3559b3db3064da88ec438e477c1f' 
  AND token = 'ysnx23s8bfAvq3jAGJnZkrdXQu5/0JdgS+aP3nFnQ+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}