SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9a33966bafc1f898d4fb30a762a9efbc34549862539262ff30ae3241cd8f953' 
  AND token = 'RykMrT6Up667dD+8MdrLk0G2yiVfzAsPS0EYeQXWqQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}