SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd5f4ae072360a634cfb99640d250844caf1223ae845d4800527d98ffb636c48a' 
  AND token = 'vD9LjNS9BgVyntomZGV3D4scuuNeDXtY8gGXFFdp+ik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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