SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ba65c335f8ff894bf1e1ceabce4d8137dfa35a805a9e048bd274fab7115160fd' 
  AND token = 'i91dImvsy4yBlCeD1h5YJXSGEObwVe3lirgi3tdYi6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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