SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8be3dd5a741fe2fb3ef361ee6f59039f04ce521b0487a20298537e0611a11291' 
  AND token = 'ncGZaX4rmckzzylvhKHjqYvTUmXurupMutb5FRemAK4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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