SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5c057dc5e8c0823eb2f22f8f099f01b0602b9ca9c4bb789506f403a8d44f93cc' 
  AND token = 'nNyC6MViWQqlxkDGzycQ2w66uQOKhB2/MUpHNvhsDVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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