SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1cff5ca25d66d13b35fe7fc37561c61580fa6e436bfcbe8f7763c23c215ce0b' 
  AND token = 'sBvAyWXnMt+E76reAUBzFOhXVbTRvL8DvtbAoUcg61E=' 
  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"
    }
  }
}