SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34f9ec71e466aeedad0d6d3ab6640a4aa185fe0e7f5bf2ade594c5c932cacc01' 
  AND token = 'UODoARqtJAumOLI8mbwa5fLmLB1YV+tPBsgWRZ34dns=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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