SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4635ceb074d476e407fcd53971f09a927aa48d1da6082cdc1e37716e831db293' 
  AND token = 'JUxYNCsx0jE+VrjwY1WnNRLt3kti/J2Xj6kwCgyVPko=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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