SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9fd56816efa0ef9c3574de972b17276e1fa6c1cf27bca17fc0d11291a7610fa8' 
  AND token = 'S97mUbP1UePPsI6mnyzlaU+maoh+2spYBR3UGqupKCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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