Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3821d9bd65bd8ef1f9d0d6b0405274e49e2beab8388310816c278d69a4d78b3c' 
  AND token = 'QavQ6YCfehW0ZpCLSwRquyl0mP1NF9nuypZiVS/ce2E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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