SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'dbf0491f787b73f534626252cfd765ec2d213534d957aa1d1445930dbd2d2406' 
  AND token = 'jTkqj3ErgH4hLtGRv+oa6aG6e2gK5mhWIPbFWuAWNtU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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