SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7c3ac74dde2017910db5d89df33bff75fddeadaba018d030b3c0514b85ede0eb' 
  AND token = '7vZIxcfVlWIOpfYZGX2/mOaRLmoyciQyRXmP/giNsmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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