SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8cea0a268a204b509f3e89b6b643bd0430cb0aa205e8825c17acc1ca2d081f02' 
  AND token = '3Cx9LhwVS7x2dXJGKBvdmwIGxmLUg4hX/bLOavvJKRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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