SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f21911138a601f159b206a7a16d895033552048982950f253fc59a9d5ce55bb' 
  AND token = 'FYvliwSxw2RfulMmBSz2ow6xRfnnffsqNO9kCR7A0Os=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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