SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3784f141e21ad26c6e5ed77cde27961555d58befc0750014a6114f39b25b963' 
  AND token = 'ZAltFrKJ5piyJsr1eCZlC+xX1P4+QyFXCeCJdZM86Ao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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