SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e247afc242a544b10fe5313d7b283f212973264dc1eed1e5d8fb560c4d76222' 
  AND token = 'GuXBPfS25jhv7PmO884rHKQB/EqNZYjU0OXFZb4Dstw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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