SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca496c85ff515b25fa0a80b1be9e296baf08883fde201ab1c6765c80fc8523ea' 
  AND token = 'AkqtYW21RCFs6Lba/u3e+ZQ339A6RIieyT2qew0GsAc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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