SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d5390987317670f6af34c3327c9cbb8c3a49a295e6b86d7e82bcd14a288e6df' 
  AND token = 'qUOamns6NLZeYyROTMMEMhC/xiNMl39eW7/mFQbO69w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}