SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7364e0915479ba36bf0aaa95889473d7afb7e137277768ed1455ef380c7c5377' 
  AND token = 'P4kgcFMBOpwBvR5/CmjAHHBhQj4DekvfKP9Q+BQ9p4U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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