SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '201768aaa57e28c2acc3021817ae1cac691bcebaaac07f9ca1313f98c30df784' 
  AND token = 'Wm0mDBrX4scEbt0cpa6IF1eZzB0cdJ8q6DsEGaFd+/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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