SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1a6e2895ff8edc15e9fcf701ea630439304761e2f3ff0147d738a8c1ba141d9f' 
  AND token = '0aAWG+fOyqC7XbhC2vCsDIutUbIXyQsZIj4Jjaghd38=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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