Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0121ddaa5cc2aa2ab870da312f6a2ddd0c9ae9ebcde6bc31ee7d3edda158963' 
  AND token = '3XUW2zN/lttdaqVnG7HStFWjcJyutCTHNnZxmGocc5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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