SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7bad67522cacebf5fbfd292fd0145bcb5fe3bec70818d58591c568814a1802c' 
  AND token = 'S6bR9mbNyf2jAMDxWGqhX5irU0wAViJODL7Nv4XzAhA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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