SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d60f459a908cb5f55a84644c50b8b70989cf0fa9570a5630f51b8b1e355e31b' 
  AND token = 'Pdw9HZwQXjsmdX90cS+FS/7hlmgenv+eFQKhy6ZrGts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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