SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '57e2975bc6b619e84457f6bc79bb6fd6c98818ea7b6b7847b9f575327d9e822b' 
  AND token = 'RJUILzWBUzg1z/e8QJ3iaydKKRtwk69ZXzzvQzhwtPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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