SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ffd67da5caf55fb330f15317a9f01d8a4cc74671a46d6cf446c708baac327ab' 
  AND token = 'DZv0t3XYtS/ej3lDYwPI8U/bA9RMT9JoB/GgCgV5JY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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