Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '39c491414e437ad46a4dc6a62d17f043477ae2d8ea603b3e939fe3f77becb4b5' 
  AND token = 'nRUbS7p/4RiqxIgHAubLQ2kLCpF+ac0oiULQYn0fPaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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