SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a09cbdababe1c1338c593b9b9b50c94daa28895ef385025c26e292caa95da2f' 
  AND token = 'ALXih1aFj5vR97ZzV5mCy7eH1r0COCKsBOi32JIiCBk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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