SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4652053ac24f41334e4e9ad09e496b33b83b5cbfbfd4a23d1724a46e9b132a1a' 
  AND token = 'GRFHcLb78x4nGQK+uNc9FCIOZvN8KbIYDo8zKKz/mMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}