SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1fb5ffb3ee63de858db126be0f6ec4fde8ab1555df540e60a4f907def516c91e' 
  AND token = 'BhdWB4O2u8AcfUk0990ozaK/yui6QuscdT3FWuO46fA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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