SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3f19dceb11b398463a1f7001f66e3e97f833281b5465e8e0706fb8da68f2be41' 
  AND token = 'dbXmSCo+uHtKn1pG/4jDsxmq3CyVQym/T/rxDiWbB+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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