SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0b3e394f28648e3cf0d2111266143be96bd58aa157f41d6a46ce46c975273982' 
  AND token = 'UGJ0ZTgVoP/K8wLQgi/0a2+mzCbsPI1t0/rsgQLa3y0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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