SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7ea0666be4470fe668b5908234ecb8b9ae791b47c6152ae7881030bacb6bbd3' 
  AND token = 'OPOf/xrz3Kif0ICLJRNgTj7C64x+e6C4fnWbLekJXic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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