SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a6c119004a8456a6462aa153678c7cc70215c282af1da7d46c039c5201d0e686' 
  AND token = 'efQ04GpqKGoMHhBunbOY/Kjimve5lvvDnVOnI4RimRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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