SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5f5478ecec6b0751008366afb590561cb81640d4272176f667c5c604e528306' 
  AND token = 'YphZL9fCngXv9q3np+XT2Y/+6+RA9DkB9beQnQbgsfc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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