SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3384aa80bcc0da86eda2ddf9c6b98be320641761a6996925c221dcd7160f616' 
  AND token = 'oZxCMtPopdkeYMvyfLzpS6sM6LsSPCFRvPUQ5cPLZ1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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