SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8df45c8a5deefde87b89dc9aaf230b286517682ca801e8118ad8c38538c92a3e' 
  AND token = 'LCLNWUtrYsWBs98yCGCNIKEe0WlZjpgfbHZoYFdlbzU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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