SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '692083332e58f18c7e34e7e164d1f7f78994fa163480dcb242fb012ccc89f1b0' 
  AND token = 'baBQuPcllIUFrfElHstOX9xBMBJRZ0vMHqlJYwHKr6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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