SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bc89a2d6e4ee0ae45ebd8635cb825af39c3dc4d90550468172b5092524b424e' 
  AND token = 'vD4XYcWQOpe2hFqzUb2XBMprVHcculY73W4mJt4kdmw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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