SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66d031d88248052bd49a1eac0b08c3d773f98e6022da7fb00f6d14f2abf6ef1c' 
  AND token = '4EcDJ0R57M9za8dxWlSorIaPIkfOI1fzURUgGCuz8o0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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