SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e96e4d3142287923c72f6601bd70893f5f53a1896d5b355317423a38ea8c1e9' 
  AND token = 'Ci89a42KFjqvRWwU2QW+xryJCxLuo8NB7L0iVqkGoIk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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