SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2272e308ebafe5abd498459d9eb803f29e9ddb289a2c7445a0e91e810acc2c8c' 
  AND token = '5LC+QTKf7ny/u0yWS6MIlhSW0NgPVmT17M/6VnqVIVo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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