SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '59059effd99727373725758f31aafa1b412909e9c9085dca7ff371c90bff3a41' 
  AND token = 'EAkKgqSE0qN514xG2zM1WE0JBAf2Ze7EXFtndooFQow=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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