SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '610293afc293fdcd94284810c45acd314b19ccefcbdc5acfc4ecf6765e150837' 
  AND token = 'aoPVXbb7fa07N8eIkGjbnKotefXdhsoEYd8KsMdnDyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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