SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ef1ef87e32df626661f89a164440d8a93ce0dcfbd6faf884cca066281198788' 
  AND token = '2ZFrhE2Lertc4d/fRbdCpph1/8IvWkuREsbzrKtCZ48=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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