SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9eeed33fc5cbf76fe274d0d2133bc2ec07917f0f03658e6c12199ff247958693' 
  AND token = 'HqwGnj8Vdqpc5VZKEv9U3Ny3mq1dn1X7zT9RAQzkne4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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