SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '532c87133eab4393d70ae96c9efe8bb5e4d23a2c00aaef9dd0b47f83a18a15e4' 
  AND token = 'PLfoC0wx2EXwVCUOadZiL217cvjJz4mrIYrPOyuEiUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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