SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3e8d3e73fa993e0b41375b88597637245f2e1c27463341e1f149389e727c3202' 
  AND token = 'nYQS8aUa7w8z8os95CyqGbIhGOK8DiTvml3gsb+PiJY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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