SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24727795a636e2623548b8f795ce5362b179b4929d348ad527521c598bd644ba' 
  AND token = 'KC5g0cT6uuJXuqjgJt+OZDdOtcx8A/7BM+YKc+BUQNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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