SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43f13a5a6cfe90b5506c796fdddb4211bf3b1ae5350c6e28640265d49e15fa65' 
  AND token = 'n3DA7pW3OaARjzEIxv6yayZXvf5QNu9T5uwHmVeyOww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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