SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7086b2dd0e62fcb6b7949a58a8b21b6891eaac1ee462c33bd08c3145954f9a62' 
  AND token = 'ybDZjBeGsHrlAAteZQYBxGtJ9mG5h+zhCt0LrtTPFJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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