SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '39984d23ca970cb21dab9ebd02575882b63a19ce9b4cf6449538ce8592323026' 
  AND token = 'UihURGOjGSX9YoxviRUY4ICCvqr9ennYCdrS1VqV0Bk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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