Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ceb39d9a9e07fc89727a748c968c6a4777e24e7370b12013badd750a327f71e3' 
  AND token = '4hNdXbTTrpatXjQVWz1OatEpIcrbDPGATkNciffQkjw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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