SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '667d6fdb6fd94890ded337590aceadad2bfac2bfc52bccb27bcef7894c91c82e' 
  AND token = 'LvqTrTWPyrw1jcBT+Pe/tLXgo1E7m/H+6q+1mCUP2is=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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