SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6c025d352b14d3c0c6b93f9c59c6bb47989c55ad8a2f6eee97b36fa53fcdd0d4' 
  AND token = 'IfJrpTqrNGXVbAJbhS4LXwyRt4u5y+1ivL80m1vji/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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