SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '281f5b6836a0713e550bd5af8b3facfd9d453d4a6873c434f7b7a0f3eadf6b13' 
  AND token = 'kostZxh/xicRWhhN8ZChXIxphX1BB74LNH5YOOh8ZSU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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