SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9537a1e78c5bbc3e74ba8bb8b67c994bda03a0f4d416e6daef4312ddf6710aef' 
  AND token = 'YW/BtFi2+bENz5Tm7A+BZ9WuuFWwU48SlHoHFgXGZNU=' 
  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"
    }
  }
}