SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c9999959624b97201e8d80095de56f040b80bfcda36316c9971e653585cac97' 
  AND token = 'Ys5Un1zcDa8UdwWb25prN2BaXx8ehYsYCNe/CQp1baw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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