SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f43718db427e160ce90f30d67b41b1d4e906e40641da8718ff5a78d1e4381335' 
  AND token = 'FZp9JCdLer5g/gIqmRnOXr+CR2qhBU02HREVfGpA6Kk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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