SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41574bfee6dafbcf3a458f805378562eda7e9f65ea5f80da412ee7a92f10cb92' 
  AND token = '3hmvPpgOfqbJG0/OgTlfohzmgaikqlG/nYQ+66Vdqto=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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