SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fcebf0a424bcf2cd4f1212fd8c2808e2ea7c0d4f66cc4c83ecc9e4cfba6f1d43' 
  AND token = 'w4aFAAm+/D+WRMD5HG80pQLLjOC557uUiSs3+pMvlJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00075

JSON explain

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