SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a17759740978cadc09cad97e451bb7175d8bcaa9eedcd0304038ce69140c84b0' 
  AND token = 'woi+yX2YDqAOgkPCjSGYY9UJcInh0iPdHWj8YGGNm9A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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