SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98df3635c362e8246f329febf88de445d5091f8efaf5cb911415ea1edd8b7894' 
  AND token = 'PRY3fb4i7rzRrgBk+G4SMj7ZV3G/voA0pRuOnjvQHow=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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