SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1bde6f41ce7be7924141ecf97d2f3d88c140ceab035fce5415fe43293fd48a9' 
  AND token = 'ZIZm6Sks+BvdDzqRLFol/JpwobVtH+VsV/kcbdWWdjU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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