SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a08dbbb9f187a50353eb53a486aec37b693c6cbc107ebe13dbae928cca2c5e79' 
  AND token = 'iocCk80i5zl+ngNMYPM1sQwgk3c3UTYG+DfXgIo2gKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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