SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ada96e0bfc538f7344e5bc88a8fa211b2d106789f33f6c1b6568e7712a93187b' 
  AND token = 'Kl+IwE2p7bUZNWqWSHF+VGJexwe8/5lzDQCjxZ80FDo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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