SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05b8e2cd5e2e83abc9fc8e81068d2602da39fd76a66e86d7ba5aa93904b91be8' 
  AND token = '88aqkZ1iAfvBIxbNKpZgYdqdEcn74O5XpFCTd3EWcEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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