SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2cd09ac79723d83698e97068e3429366589ae9f8ae27c226fa00ad7969acea5' 
  AND token = 'WlRNJtTwGu3jeUglpcqfeDj43Wy7ZIbRxERqpaRKTo0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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