SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23aa333c12bebcd020cb8b317d1277a8bf7aa691f6403ed9b25b8ab3ba7892b0' 
  AND token = 'FjpJxKEkchtZmmHanPBGm1gmu0WqJXHa+lroShtGcyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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