SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '81af71e3c30e8a91c2332e86ccbb17a86c32ab5502586ad65d0529bd3aecf532' 
  AND token = 'A6w5gHuetzljBgLfKJpyNgFvwgmAy66M+5V+lWQWy64=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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