SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '43a1cd9a29de69227394dfcda17fd2a83d78faf211b62eb8b65dd48c06fefdfb' 
  AND token = 'jpmQTHGqqthUk/Lsl6gIgEGoavn/vUQjlycfBxBkF+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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