SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b23d5c2148d5b11c6d3235cf3b4de10af88004757a118ed0a28df8fbfd0ce8eb' 
  AND token = 'C7DL5Pjo8MynrF/a0H18UDLuMpjHpcLR7ADXyXAs2jI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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