SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9a243a5b8b96171cbd5b6e207e1bf118fa4ab9a48ba7f5aad7435b20c462efd' 
  AND token = 'MSNCl/XGV3KIXrWmtBsogNwZDOrR4iCken9xRULWlIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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