SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97755ac0abcbfa5dfec19976c87cff8681f95c00c71e5394bf0d40c0bb4ae8ec' 
  AND token = 'Q1YOMRFDsUPv1REdi+7HcUPOHwGSfe38Wqpjriwv1dU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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