SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0dcc35af85bbfd8ebe2a1438d0d19d6ac6d207882077b51b934bd017771dcf89' 
  AND token = 'poaShoJqYkpr9pmpbGmgI5G3kJX+JzRMFmcqZLUCga0=' 
  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"
    }
  }
}