SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8c32e363a31f7edad5470128bd53e6ffecfabce6217dfcd7b7a7fa542b24f073' 
  AND token = 'EP0ErIeTUNQQeJCiG8Idp3nZ6r1yCDQWt9VyMnmL3W4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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