SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45eeee33bb7df6fb445094fb897bb5f4a7bc1e7473c07499dd7d5cb67d2afd21' 
  AND token = 'HmdUOnMuHczwAL6fMvdkvMSnDZ8cPDJA9oGDp5sCU5Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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