SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3e773ffe59ba6adabda72ea067d33cbafbeac15b68600602d05f0fdf365f2d5' 
  AND token = 'vofzdHzgJMMEbSf6gHBOlg74gDL/OG4UYdr2hnphLTA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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