SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '133fcf05b189d2821112a2b6a9664cb6cb40d345debbfabbffd926b9faf008ed' 
  AND token = 'iim7o86z4HhLITs8NCrbksqBKjUimkfnM5qDjfxuV7M=' 
  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"
    }
  }
}