SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afd5906fd74a313015961e4c321c4267ff331458db7ffc3d1c4ac12c1f2323ac' 
  AND token = 'qbzl9r01oguE6Xu5yEET9ygP+VQgboPjhN52sJg3lGo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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