SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '79afc466b68c71466621f5a519c8d4b517232d8bccf31de1daa98750322fc439' 
  AND token = 'bk/d+fahLZn3VkdDVnr7DYEXMuv7I6StE+5Xsqh3SJE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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