SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbf319fa24c29f57226a2ecd533e7ec2db79efeefeb7ef9cec612fe697b86d5e' 
  AND token = '6j16CIJR8Eqpdsmnn3LY0sjq3nYvBmYAqfSP5FIgOfk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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