SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '81a72152343b4ca3a3f6f998c676017bd07ba3913b9b7f028ca986faec0cf168' 
  AND token = 'UrtmdeCz+EOYlUpxxwifL+gOAXa82wadlcHOIprb+7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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