SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0baafce291730271e8d61c66400c4e0829b54df0f1a37e5a5225f22ed862a484' 
  AND token = '+YornI3NyWxE5m6fpVq3DjhzWuY59CIcaypHGNXoXec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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