SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58a764bdfa3433626f1c74c57a0f2d27e7f2b0838e977c34145edf6f27225899' 
  AND token = '8XTJVuAujZKfVXNbpSZ5G1yHWAE9LHiYn5PLbtJfgW8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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