SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7cc7031664bfa6f02bed8887dc6dbb16e94028db5f1fc6362accee6e9d3e442d' 
  AND token = '4TXau5XF6bjLIjoHkYUlEH7ZzzHn+8QoPyw4p9zsTWo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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