SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8dc6da8911e27b868c6fee0c105de75ea945ab2e51ff63708487267236659956' 
  AND token = 'FEMDMLcAE+3aSDIxJ/GA1bO8ldubOzo2XQYZ/vVW/3Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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