SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c8df9033c6fa992be9c4d2060f0efe85dbcaaf1102f7c70cea43a4dc97bbebe9' 
  AND token = 'AIikLwB0BR4UDMIXtJ8Rk58kriPaBkbHTbtOvCMG1Us=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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