SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78004c82b01c395ed53f7d6dee498327bdbe3cf895670328f869f942eb1d44b7' 
  AND token = 'aFHFNWZP7Y0B41nMs8oL54bmNdmZRpC5YxTiTU8TmNg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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