SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9cbc5a972432ee657844d5b628ec5a98f594d13053c14a97f27894642d73975' 
  AND token = 'XODbyK/R6tO/qrGVAtHEk2blP8i4NnaVwcb9lggVwSI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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