SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7ad3d45ee32f4fc2df7ed113ddc2464bb426a589935ccca5bd07528e84b164c0' 
  AND token = '6CsayRRzSOeXiKuLrlPt3Wgq4R1QdsfdUzX+/LWSxBo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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