SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ed86222c7963c84d3d6462eb496a5390275856cfc2906051ab3a92e183b4827' 
  AND token = 'OdaEDGw8VChHfFImxyh0OIZFit0rRDYdxF6oBs3gLH4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}