SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2a2f78584da07f23072dedebf3a51a445fd05f0d200fa4c1754c82d53ec0f83a' 
  AND token = '0jFnJ0sxqst7butnKQ9jPTKreuRZNm7DNkn/ouCcYhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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