SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5cc466a7c1e8b5ace12245ab5dafb4b48f546bad9f3984c19ddc7bb5e2dba3e8' 
  AND token = 'zBEX6dBSJ2kFLduyGrIl+UjdyPvgmCHLEtR4oXO/AvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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