SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '342580f564b291e4dca4652b209bd10593ca6fef59e13b0df4c358885a59c69f' 
  AND token = '2Zzo/5Gsa+ig1m4mcvkKDFsCErrgw/MK/QiYf7vGEz4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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