SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60999fb4ef11c3bd79f1aafa9dd7fd2838740954c061939b0b84e3db5accefff' 
  AND token = '/vxD/hlVaks2H3kc+b7oI1cJZADwEeshAMJ6rZrTOoU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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