SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87d692598b8e987e72f437334a7e316169d66881e8c90a01172d9d34bafbb308' 
  AND token = 'blogxnachF7IsWpFUFpKExh+rpzHJxkob+s5XbH5qDY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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