SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f17340c60b98ddee23cd3bdea5b686560e9d5218eb41e89a2a8f87d05be74efa' 
  AND token = 'fy9L4QzVYd+GQjspm74S2SpqgIt676v6ZmWNUHfercM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

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