SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddbf7179b5b4214d0f5ed84737a04caff46afc8ad418ea0e21d5fc1bfbc948b8' 
  AND token = 'ghQHZTV5bJsQ/FToyXqvlLn6GLx9ZsaLHC1WofTrOUw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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