SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec62ff582d323fb5fd8e9452d7b1dc3a7bb3accde497a5412a94b586cd467148' 
  AND token = '5Uxe82uLKrdh7YLZLzaoVJqqPYIclPwMDc6V1kLRnB4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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