SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd625ef05198bb56e27c80d7bf3ce1f153a53b6469e8e5eb00681c9c06665ca35' 
  AND token = 'Wqn+ii03Wkj5ctMLW6Hxlm4tGeo8/ocX6iYjscv5fJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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