SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6ad6ecc1ffd737999b3d99e661697314fd0401043704273ede6efb81fc21ef3f' 
  AND token = 'Qwo1K4VqF1N071p/+9sXu+X4lMniDjIEuWPhtNBSNbQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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