SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '181df8f5e0b72a5bddc5a132c227ad107338f5b26f881a877ec41e4638e357f8' 
  AND token = 'uufUeL2lLQNxJ3N2POqdlVZVshlllMEVH/qQ3pywoGA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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