SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '93a82da713506cbe29c0f86d9e8c9c6e5abac709f6574984abba3d13345d9733' 
  AND token = 'GwGgD+JFcUkeIvEkS544X4UIV0pw01r8VQnxIRBzp1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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