SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a2aea363fb892c90e2f22008e2a371955133754d7bca9a5131878b528fb6ba0' 
  AND token = 'Kz7qBKKVWqKMizwc6CmYGYr68jhVGZ89jKso9LObnDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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