SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ba0ac118b80c33716293c7769ff932a0da77a72e9f050549711ebdfee054651' 
  AND token = 'vmXfRmmSmSXwYp9zvYm2kkehxg2DMOs5j5o98HppzsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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