SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '76c246d0547fc0198f1e8ecd70268228119e8129ff75a63ca4eb092e8d50086f' 
  AND token = '+BlLzb/qDL6zLdnycIXUp+LJqi1YmbcZY55C67tqfVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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