SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96c0a49051d7cd9d194fcece54e1a1f046cfbae896d6a1a67f982c504eb0658f' 
  AND token = 'ITXfvHC/ClIoR9fPmLlyeb8pAdM95XZbI166wFOatJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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