SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8d39980b191c4e029b58d39b0b1d5c558f20eec4ec856380b3da122d80998f41' 
  AND token = 'KXfUcP9OA97P4OG1v4wBTn2sEBufsExKAtqDQPMbiyI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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