SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45a9f1d3a1aaecc9c8a41db5eb132ff337e5d92f67f272ce4c8f3d20226983b4' 
  AND token = '2CV39jvddjQ7pRjpLb9FyPNNMRPMzxmqcTxiQeT6TP0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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