SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13d6a1c39619c75b73b6a91c882dbc1b918b7a8db51366cc6a99621dffc13d14' 
  AND token = 'q+2GaYGRDRlZp97l3JzN23FKy0O9jZqb/5qCKQbsvag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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