SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c3e269c3c1cfd8c3447ef25fcf32d58461b51080682afcb1ad827fc29f33c5cc' 
  AND token = 'uSBykzF2My6/AgT8cjIVpyN+QbWGXdk1RokSXYLsGyA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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