SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e898aa134c3ff9736b52c49f97e8ca82c874beaca8de5937cdc19a3b19e146fb' 
  AND token = 'DyXMvCFHrtS3jJyJeOUawcfsqGY47qo1ugStij/e9dc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}