SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c72ca093f4d1abd069c15f39d9a12d6d000c687681a9c628b9804d0a881deefa' 
  AND token = 'hNjVHpwmzwfbmRHtdRNrzIm+8qOYMiI7ePeyH/vHREE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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