SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bcd5e36fd00b9731da433b8a4cd2a5988b5374dbb0055345323e6d286794bf00' 
  AND token = 'LiwwAr2tqRL1qj78WDLTYZV4A3RjJHhPFJKnlt6fH5I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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