SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebde5175e22bf01188d3bd930327c767ec5393c0f120c629529699b74547a2d7' 
  AND token = '/l1+RHtBi//3TrqTxur2AQydUoztTDbzrlRx3d/STWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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