SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f7007ccef4454e77cf1196e4d1ec227cf379055d266140413920ce44c2f019d' 
  AND token = 'fNwwyy2Bl1Cac/QzPSxBmCq8EOX63VNr5LTwHlTdM4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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