SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1433d0ea357d360cae337234475c551af01233398e4b5267bb0e297e32ee5534' 
  AND token = 'BRRpAtCuu2RC5a3jkx5Nin/MJyBATCLUfnoSuZmqQks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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