SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca8d83cfdb274afde1365efbc1ac9ab45458f7a2cfceb8d63d9b81b576225939' 
  AND token = 'jG53Xag5FGLzIlo0HS8jErYYe8W6K0qnj+wYevQXMBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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