SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd36f0fbaa0f28a8b0d1f4057f414d9b04203879d749d25f449e0ef7c630d8c5d' 
  AND token = 'WjFkEd68NV2lXgJOyxgxNY5mqmwpI3Sz5esv1yWnWJE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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