SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a2c4ffa0abf4fe9cdde025925823e7676fd2eb25ac26aea84f7c4e96eb48200' 
  AND token = 'NoglWuT9L+CAEtjWzNfZvYGUHiSXxd23xHLmEniki2M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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