SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c53b48aa3b7312ab7b07ecffc42f680acf95a350a346e2472cd7f5025d54088' 
  AND token = 'QBJqikI+w9eCJyyVcbATGgnzd3ickE8vXJzHK3yr9cA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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